วันพุธที่ 23 กุมภาพันธ์ พ.ศ. 2554

Volleyball


Volleyball is an Olympic team sport in which two teams of six players are separated by a net. Each team tries to score points by grounding a ball on the other team's court under organized rules.

The complete rules are extensive. But simply, play proceeds as follows: A player on one of the teams begins a 'rally' by serving the ball (tossing or releasing it and then hitting it with a hand or arm), from behind the back boundary line of the court, over the net, and into the receiving team's court. The receiving team must not let the ball be grounded within their court. They may touch the ball as many as three times. Typically, the first two touches are to set up for an attack, an attempt to direct the ball back over the net in such a way that the serving team is unable to prevent it from being grounded in their court.

The rally continues, with each team allowed as many as three consecutive touches, until either (1): a team makes a kill, grounding the ball on the opponent's court and winning the rally; or (2): a team commits a fault and loses the rally. The team that wins the rally is awarded a point, and serves the ball to start the next rally. A few of the most common faults include:

causing the ball to touch the ground outside the opponents' court or without first passing over the net;
catching and throwing the ball;
double hit: two consecutive contacts with the ball made by the same player;
four consecutive contacts with the ball made by the same team.
net foul: touching the net during play.
The ball is usually played with the hands or arms, but players can legally strike or push (short contact) the ball with any part of the body.

A number of consistent techniques have evolved in volleyball, including spiking and blocking (because these plays are made above the top of the net the vertical jump is an athletic skill emphasized in the sport) as well as passing, setting, and specialized player positions and offensive and defensive structures.

History

On February 9, 1895, in Holyoke, Massachusetts (USA), William G. Morgan, a YMCA physical education director, created a new game called Mintonette as a pastime to be played preferably indoors and by any number of players. The game took some of its characteristics from tennis and handball. Another indoor sport, basketball, was catching on in the area, having been invented just ten miles (sixteen kilometers) away in the city of Springfield, Massachusetts, only four years before. Mintonette was designed to be an indoor sport less rough than basketball for older members of the YMCA, while still requiring a bit of athletic effort.

The first rules, written down by William G Morgan, called for a net 6 ft 6 in (1.98 m) high, a 25×50 ft (7.6×15.2 m) court, and any number of players. A match was composed of nine innings with three serves for each team in each inning, and no limit to the number of ball contacts for each team before sending the ball to the opponents’ court. In case of a serving error, a second try was allowed. Hitting the ball into the net was considered a foul (with loss of the point or a side-out)—except in the case of the first-try serve.

After an observer, Alfred Halstead, noticed the volleying nature of the game at its first exhibition match in 1896, played at the International YMCA Training School (now called Springfield College), the game quickly became known as volleyball (it was originally spelled as two words: "volley ball"). Volleyball rules were slightly modified by the International YMCA Training School and the game spread around the country to various YMCAs.

Refinements and later developmentsThe first official ball used in volleyball is disputed; some sources say that Spalding created the first official ball in 1896, while others claim it was created in 1900. The rules evolved over time: in the Philippines by 1916, the skill and power of the set and spike had been introduced, and four years later a "three hits" rule and a rule against hitting from the back row were established. In 1917, the game was changed from 21 to 15 points. In 1919, about 16,000 volleyballs were distributed by the American Expeditionary Forces to their troops and allies, which sparked the growth of volleyball in new countries.

The first country outside the United States to adopt volleyball was Canada in 1900. An international federation, the Fédération Internationale de Volleyball (FIVB), was founded in 1947, and the first World Championships were held in 1949 for men and 1952 for women. The sport is now popular in Brazil, in Europe (where especially Italy, the Netherlands, and countries from Eastern Europe have been major forces since the late 1980s), in Russia, and in other countries including China and the rest of Asia, as well as in the United States.

Beach volleyball, a variation of the game played on sand and with only two players per team, became a FIVB-endorsed variation in 1987 and was added to the Olympic program at the 1996 Summer Olympics. Volleyball is also a sport at the Paralympics managed by the World Organization Volleyball for Disabled.

Volleyball in the Olympics

Main article: Volleyball at the Summer Olympics
The history of Olympic volleyball traces back to the 1924 Summer Olympics in Paris, where volleyball was played as part of an American sports demonstration event. After the foundation of FIVB and some continental confederations, it began to be considered for official inclusion. In 1957, a special tournament was held at the 53rd IOC session in Sofia, Bulgaria to support such request. The competition was a success, and the sport was officially included in the program for the 1964 Summer Olympics.

The Olympic volleyball tournament was originally a simple competition: all teams played against each other team and then were ranked by wins, set average, and point average. One disadvantage of this round-robin system is that medal winners could be determined before the end of the games, making the audience lose interest in the outcome of the remaining matches. To cope with this situation, the competition was split into two phases with the addition of a "final round" elimination tournament consisting of quarterfinals, semifinals, and finals matches in 1972. The number of teams involved in the Olympic tournament has grown steadily since 1964. Since 1996, both men's and women's events count twelve participant nations. Each of the five continental volleyball confederations has at least one affiliated national federation involved in the Olympic Games.

The U.S.S.R. won men's gold in both 1964 and 1968. After taking bronze in 1964 and silver in 1968, Japan finally won the gold for men's volleyball in 1972. Women's gold went to Japan in 1964 and again in 1976. That year, the introduction of a new offensive skill, the backrow attack, allowed Poland to win the men's competition over the Soviets in a very tight five-set match. Since the strongest teams in men's volleyball at the time belonged to the Eastern Bloc, the American-led boycott of the 1980 Summer Olympics did not have as great an effect on these events as it had on the women's. The U.S.S.R. collected their third Olympic Gold Medal in men's volleyball with a 3-1 victory over Bulgaria (the Soviet women won that year as well, their third gold as well). With the U.S.S.R. boycotting the 1984 Olympic Games in Los Angeles, the U.S. was able to sweep Brazil in the finals to win the men's gold medal. Italy won its first medal (bronze in the men's competition) in 1984, foreshadowing a rise in prominence for their volleyball teams.

At the 1988 Games, Karch Kiraly and Steve Timmons led the U.S. men's team to a second straight gold medal. In 1992, underrated Brazil upset favourites C.I.S., Netherlands, and Italy in the men's competition for the country's first volleyball Olympic gold medal. Runner-up Netherlands, men's silver medalist in 1992, came back under team leaders Ron Zwerver and Olof van der Meulen in the 1996 Games for a five-set win over Italy. A men's bronze medalist in 1996, Serbia and Montenegro (playing in 1996 and 2000 as the Federal Republic of Yugoslavia) beat Russia in the gold medal match in 2000, winning their first gold medal ever. In 2004, Brazil won its second men's volleyball gold medal beating Italy in the finals. In the 2008 Games, the USA beat Brazil in the men's volleyball final.

See also: Volleyball in the United States and Volleyball in Canada

Rules of the game

The courtThe game is played on a volleyball court 18 meters (59 feet) long and 9 meters (29.5 feet) wide, divided into two 9 m × 9 m halves by a one-meter (40-inch) wide net placed so that the top of the net is 2.43 meters (7 feet 11 5/8 inches) above the center of the court for men's competition, and 2.24 meters (7 feet 4 1/8 inches) for women's competition (these heights are varied for veterans and junior competitions).

There is a line 3 meters from and parallel to the net in each team court which is considered the "attack line". This "3 meter" (or 10 foot) line divides the court into "back row" and "front row" areas (also back court and front court). These are in turn divided into 3 areas each: these are numbered as follows, starting from area "1", which is the position of the serving player:

After a team gains the serve (also known as siding out), its members must rotate in a clockwise direction, with the player previously in area "2" moving to area "1" and so on, with the player from area "1" moving to area "6".

The team courts are surrounded by an area called the free zone which is a minimum of 3 meters wide and which the players may enter and play within after the service of the ball. All lines denoting the boundaries of the team court and the attack zone are drawn or painted within the dimensions of the area and are therefore a part of the court or zone. If a ball comes in contact with the line, the ball is considered to be "in". An antenna is placed on each side of the net perpendicular to the sideline and is a vertical extension of the side boundary of the court. A ball passing over the net must pass completely between the antennae (or their theoretical extensions to the ceiling) without contacting them.

The ballMain article: Volleyball (ball)
FIVB regulations state that the ball must be spherical, made of leather or synthetic leather, have a circumference of 65–67 cm, a weight of 260–280 g and an inside pressure of 0.30–0.325 kg/cm2. Other governing bodies have similar regulations.

Game playEach team consists of six players. To get play started, a team is chosen to serve by coin toss. A player from the serving team throws the ball into the air and attempts to hit the ball so it passes over the net on a course such that it will land in the opposing team's court (the serve). The opposing team must use a combination of no more than three contacts with the volleyball to return the ball to the opponent's side of the net. These contacts usually consist first of the bump or pass so that the ball's trajectory is aimed towards the player designated as the setter; second of the set (usually an over-hand pass using wrists to push finger-tips at the ball) by the setter so that the ball's trajectory is aimed towards a spot where one of the players designated as an attacker can hit it, and third by the attacker who spikes (jumping, raising one arm above the head and hitting the ball so it will move quickly down to the ground on the opponent's court) to return the ball over the net. The team with possession of the ball that is trying to attack the ball as described is said to be on offense.

The team on defense attempts to prevent the attacker from directing the ball into their court: players at the net jump and reach above the top (and if possible, across the plane) of the net in order to block the attacked ball. If the ball is hit around, above, or through the block, the defensive players arranged in the rest of the court attempt to control the ball with a dig (usually a fore-arm pass of a hard-driven ball). After a successful dig, the team transitions to offense.

The game continues in this manner, rallying back and forth, until the ball touches the court within the boundaries or until an error is made. The most frequent errors that are made are either to fail to return the ball over the net within the allowed three touches, or to cause the ball to land outside the court. A ball is "in" if any part of it touches a sideline or end-line, and a strong spike may compress the ball enough when it lands that a ball which at first appears to be going out may actually be in. Players may travel well outside the court to play a ball that has gone over a sideline or end-line in the air.

Other common errors include a player touching the ball twice in succession, a player "catching" the ball, a player touching the net while attempting to play the ball, or a player penetrating under the net into the opponent's court. There are a large number of other errors specified in the rules, although most of them are infrequent occurrences. These errors include back-row or libero players spiking the ball or blocking (back-row players may spike the ball if they jump from behind the attack line), players not being in the correct position when the ball is served, attacking the serve in the front court and above the height of the net, using another player as a source of support to reach the ball, stepping over the back boundary line when serving, taking more than 8 seconds to serve, or playing the ball when it is above the opponent's court.

ScoringWhen the ball contacts the floor within the court boundaries or an error is made, the team that did not make the error is awarded a point, whether they served the ball or not. If the ball hits the line, the ball is counted as in. The team that won the point serves for the next point. If the team that won the point served in the previous point, the same player serves again. If the team that won the point did not serve the previous point, the players of the team rotate their position on the court in a clockwise manner. The game continues, with the first team to score 25 points (and be two points ahead) awarded the set. Matches are best-of-five sets and the fifth set (if necessary) is usually played to 15 points. (Scoring differs between leagues, tournaments, and levels; high schools sometimes play best-of-three to 25; in the NCAA games are played best-of-five to 25 as of the 2008 season.)

Before 1999, points could be scored only when a team had the serve (side-out scoring) and all sets went up to only 15 points. The FIVB changed the rules in 1999 (with the changes being compulsory in 2000) to use the current scoring system (formerly known as rally point system), primarily to make the length of the match more predictable and to make the game more spectator- and television-friendly.

LiberoIn 1998 the libero player was introduced internationally. The libero is a player specialized in defensive skills: the libero must wear a contrasting jersey color from his or her teammates and cannot block or attack the ball when it is entirely above net height. When the ball is not in play, the libero can replace any back-row player, without prior notice to the officials. This replacement does not count against the substitution limit each team is allowed per set, although the libero may be replaced only by the player whom they replaced.

The libero may function as a setter only under certain restrictions. If she/he makes an overhand set, she/he must be standing behind (and not stepping on) the 3-meter line; otherwise, the ball cannot be attacked above the net in front of the 3-meter line. An underhand pass is allowed from any part of the court.

The libero is, generally, the most skilled defensive player on the team. There is also a libero tracking sheet, where the referees or officiating team must keep track of who the libero subs in and out for. There may only be one libero per set (game), although there may be a different libero in the beginning of any new set (game).

Furthermore, a libero is not allowed to serve, according to international rules, with the exception of the NCAA women's volleyball games, where a 2004 rule change allows the libero to serve, but only in a specific rotation. That is, the libero can only serve for one person, not for all of the people for whom he or she goes in. That rule change was also applied to high school and junior high play soon after.

Recent rule changesOther rule changes enacted in 2000 include allowing serves in which the ball touches the net, as long as it goes over the net into the opponents' court. Also, the service area was expanded to allow players to serve from anywhere behind the end line but still within the theoretical extension of the sidelines. Other changes were made to lighten up calls on faults for carries and double-touches, such as allowing multiple contacts by a single player ("double-hits") on a team's first contact provided that they are a part of a single play on the ball.

In 2008, the NCAA changed the minimum number of points needed to win any of the first four sets from 30 to 25 for women's volleyball (men's volleyball remained at 30.) If a fifth (deciding) set is reached, the minimum required score remains at 15. In addition, the word "game" is now referred to as "set".

Changes in rules have been studied and announced by FIVB in recent years, and they have released the updated rules in 2009.

SkillsCompetitive teams master six basic skills: serve, pass, set, attack, block and dig. Each of these skills comprises a number of specific techniques that have been introduced over the years and are now considered standard practice in high-level volleyball.

Serve

A player stands behind the inline and serves the ball, in an attempt to drive it into the opponent's court. His or her main objective is to make it land inside the court; it is also desirable to set the ball's direction, speed and acceleration so that it becomes difficult for the receiver to handle it properly. A serve is called an "ace" when the ball lands directly onto the court or travels outside the court after being touched by an opponent.

In contemporary volleyball, many types of serves are employed:

Underhand: a serve in which the player strikes the ball below the waist instead of tossing it up and striking it with an overhand throwing motion. Underhand serves are considered very easy to receive and are rarely employed in high-level competitions.
Sky Ball Serve: a specific type of underhand serve occasionally used in beach volleyball, where the ball is hit so high it comes down almost in a straight line. This serve was invented and employed almost exclusively by the Brazilian team in the early 1980s and is now considered outdated. In Brazil, this serve is called Jornada nas Estrelas (Star Trek).
Topspin: an overhand serve where the player tosses the ball high and hits it with a wrist span, giving it topspin which causes it to drop faster than it would otherwise and helps maintain a straight flight path. Topspin serves are generally hit hard and aimed at a specific returner or part of the court. Standing topspin serves are rarely used above the high school level of play.
Float: an overhand serve where the ball is hit with no spin so that its path becomes unpredictable, akin to a knuckleball in baseball.
Jump Serve: an overhand serve where the ball is first tossed high in the air, then the player makes a timed approach and jumps to make contact with the ball, hitting it with much pace and topspin. This is the most popular serve amongst college and professional teams.
Jump Float: an overhand serve where the ball is tossed high enough that the player may jump before hitting it similarly to a standing float serve. The ball is tossed lower than a topspin jump serve, but contact is still made while in the air. This serve is becoming more popular amongst college and professional players because it has a certain unpredictability in its flight pattern.
SetThe set is usually the second contact that a team makes with the ball. The main goal of setting is to put the ball in the air in such a way that it can be driven by an attack into the opponent's court. The setter coordinates the offensive movements of a team, and is the player who ultimately decides which player will actually attack the ball.

As with passing, one may distinguish between an overhand and a bump set. Since the former allows for more control over the speed and direction of the ball, the bump is used only when the ball is so low it cannot be properly handled with fingertips, or in beach volleyball where rules regulating overhand setting are more stringent. In the case of a set, one also speaks of a front or back set, meaning whether the ball is passed in the direction the setter is facing or behind the setter. There is also a jump set that is used when the ball is too close to the net. In this case the setter usually jumps off his or her right foot straight up to avoid going into the net. The setter usually stands about ⅔ of the way from the left to the right of the net and faces the left (the larger portion of net that he or she can see).

Sometimes a setter refrains from raising the ball for a teammate to perform an attack and tries to play it directly onto the opponent's court. This movement is called a "dump". The most common dumps are to 'throw' the ball behind the setter or in front of the setter to zones 2 and 4. More experienced setters toss the ball into the deep corners or spike the ball on the second hit.

Pass

Also called reception, the pass is the attempt by a team to properly handle the opponent's serve, or any form of attack. Proper handling includes not only preventing the ball from touching the court, but also making it reach the position where the setter is standing quickly and precisely.

The skill of passing involves fundamentally two specific techniques: underarm pass, or bump, where the ball touches the inside part of the joined forearms or platform, at waist line; and overhand pass, where it is handled with the fingertips, like a set, above the head. Either are acceptable in professional and beach volleyball, however there are much tighter regulations on the overhand pass in beach volleyball.

AttackThe attack, also known as the spike, is usually the third contact a team makes with the ball. The object of attacking is to handle the ball so that it lands on the opponent's court and cannot be defended. A player makes a series of steps (the "approach"), jumps, and swings at the ball.

Ideally the contact with the ball is made at the apex of the hitter's jump. At the moment of contact, the hitter's arm is fully extended above his or her head and slightly forward, making the highest possible contact while maintaining the ability to deliver a powerful hit. The hitter uses arm swing, wrist snap, and a rapid forward contraction of the entire body to drive the ball. A 'bounce' is a slang term for a very hard/loud spike that follows an almost straight trajectory steeply downward into the opponent's court and bounces very high into the air. A "kill" is the slang term for an attack that is not returned by the other team thus resulting in a point.

Contemporary volleyball comprises a number of attacking techniques:

Backcourt (or backrow)/pipe attack: an attack performed by a back row player. The player must jump from behind the 3-meter line before making contact with the ball, but may land in front of the 3-meter line.
Line and Cross-court Shot: refers to whether the ball flies in a straight trajectory parallel to the side lines, or crosses through the court in an angle. A cross-court shot with a very pronounced angle, resulting in the ball landing near the 3-meter line, is called a cut shot.
Dip/Dink/Tip/Cheat/Dump: the player does not try to make a hit, but touches the ball lightly, so that it lands on an area of the opponent's court that is not being covered by the defense.
Tool/Wipe/Block-abuse: the player does not try to make a hard spike, but hits the ball so that it touches the opponent's block and then bounces off-court.
Off-speed hit: the player does not hit the ball hard, reducing its speed and thus confusing the opponent's defense.
Quick hit/"One": an attack (usually by the middle blocker) where the approach and jump begin before the setter contacts the ball. The set (called a "quick set") is placed only slightly above the net and the ball is struck by the hitter almost immediately after leaving the setter's hands. Quick attacks are often effective because they isolate the middle blocker to be the only blocker on the hit.
Slide: a variation of the quick hit that uses a low back set. The middle hitter steps around the setter and hits from behind him or her.
Double quick hit/"Stack"/"Tandem": a variation of quick hit where two hitters, one in front and one behind the setter or both in front of the setter, jump to perform a quick hit at the same time. It can be used to deceive opposite blockers and free a fourth hitter attacking from backcourt, maybe without block at all.

Block

Blocking refers to the actions taken by players standing at the net to stop or alter an opponent's attack.

A block that is aimed at completely stopping an attack, thus making the ball remain in the opponent's court, is called offensive. A well-executed offensive block is performed by jumping and reaching to penetrate with one's arms and hands over the net and into the opponent's area. It requires anticipating the direction the ball will go once the attack takes place. It may also require calculating the best foot work to executing the "perfect" block.

The jump should be timed so as to intercept the ball's trajectory prior to it crossing over the net. Palms are held deflected downward about 45-60 degrees toward the interior of the opponents court. A "roof" is a spectacular offensive block that redirects the power and speed of the attack straight down to the attacker's floor, as if the attacker hit the ball into the underside of a peaked house roof.

By contrast, it is called a defensive, or "soft" block if the goal is to control and deflect the hard-driven ball up so that it slows down and becomes more easy to be defended. A well-executed soft-block is performed by jumping and placing one's hands above the net with no penetration into the opponent's court and with the palms up and fingers pointing backward.

Blocking is also classified according to the number of players involved. Thus, one may speak of single (or solo), double, or triple block.

Successful blocking does not always result in a "roof" and many times does not even touch the ball. While it’s obvious that a block was a success when the attacker is roofed, a block that consistently forces the attacker away from his or her 'power' or preferred attack into a more easily controlled shot by the defense is also a highly successful block.

At the same time, the block position influences the positions where other defenders place themselves while opponent hitters are spiking.

Dig

Digging is the ability to prevent the ball from touching one's court after a spike or attack, particularly a ball that is nearly touching the ground. In many aspects, this skill is similar to passing, or bumping: overhand dig and bump are also used to distinguish between defensive actions taken with fingertips or with joined arms.

Some specific techniques are more common in digging than in passing. A player may sometimes perform a "dive", i.e., throw his or her body in the air with a forward movement in an attempt to save the ball, and land on his or her chest. When the player also slides his or her hand under a ball that is almost touching the court, this is called a "pancake". The pancake is frequently used in indoor volleyball.

Sometimes a player may also be forced to drop his or her body quickly to the floor in order to save the ball. In this situation, the player makes use of a specific rolling technique to minimize the chances of injuries.

CoachingBasicCoaching for volleyball can be classified under two main categories: match coaching and developmental coaching. The objective of match coaching is to win a match by managing a team's strategy. Developmental coaching emphasizes player development through the reinforcement of basic skills during exercises known as "drills." Drills promote repetition and refinement of volleyball movements, particularly in footwork patterns, body positioning relative to others, and ball contact. A coach will construct drills that simulate match situations thereby encouraging speed of movement, anticipation, timing, communication, and team-work. At the various stages of a player's career, a coach will tailor drills to meet the strategic requirements of the team. The American Volleyball Coaches Association is the largest organization in the world dedicated exclusively to volleyball coaching.

Strategy

Player specializationThere are 5 positions filled on every volleyball team at the elite level. Setter, Outside Hitter/Left Side Hitter, Middle Hitter, Opposite Hitter/Right Side Hitter and Libero/Defensive Specialist. Each of these positions plays a specific, key role in winning a volleyball match.

Setters have the task for orchestrating the offense of the team. They aim for second touch and their main responsibility is to place the ball in the air where the attackers can place the ball into the opponents' court for a point. They have to be able to operate with the hitters, manage the tempo of their side of the court and choose the right attackers to set. Setters need to have swift and skillful appraisal and tactical accuracy, and must be quick at moving around the court.
Liberos are defensive players who are responsible for receiving the attack or serve. They are usually the players on the court with the quickest reaction time and best passing skills. Libero means 'free' as they have the ability to substitute for any other player on the court during each play. They do not necessarily need to be tall, as they never play at the net, which allows shorter players with strong passing and defensive skills to excel in the position and play an important role in the team's success. A player designated as a libero for a match may not play other roles during that match. Liberos wear a different color jersey than their teammates.
Middle blockers or Middle hitters are players that can perform very fast attacks that usually take place near the setter. They are specialized in blocking, since they must attempt to stop equally fast plays from their opponents and then quickly set up a double block at the sides of the court. In non-beginners play, every team will have two middle hitters.
Outside hitters or Left side hitters attack from near the left antenna. The outside hitter is usually the most consistent hitter on the team and gets the most sets. Inaccurate first passes usually result in a set to the outside hitter rather than middle or opposite. Since most sets to the outside are high, the outside hitter may take a longer approach, always starting from outside the court sideline. In non-beginners play, there are again two outside hitters on every team in every match.
Opposite hitters or Right side hitters carry the defensive workload for a volleyball team in the front row. Their primary responsibilities are to put up a well formed block against the opponents Outside Hitters and serve as a backup setter. Sets to the opposite usually go to the right side of the antennae.
FormationsThe three standard volleyball formations are known as "4-2", "6-2" and "5-1", which refers to the number of hitters and setters respectively. 4-2 is a basic formation used only in beginners' play, while 5-1 is by far the most common formation in high-level play.

4-2The 4-2 formation has four hitters and two setters. The setters usually set from the middle front or right front position. The team will therefore have two front-row attackers at all times. In the international 4-2, the setters set from the right front position. The international 4-2 translates more easily into other forms of offense.

The setters line up opposite each other in the rotation. The typical lineup has two outside hitters. By aligning like positions opposite themselves in the rotation, there will always be one of each position in the front and back rows. After service, the players in the front row move into their assigned positions, so that the setter is always in middle front. Alternatively, the setter moves into the right front and has both a middle and an outside attacker; the disadvantage here lies in the lack of an offside hitter, allowing one of the other team's blockers to "cheat in" on a middle block.

The clear disadvantage to this offensive formation is that there are only two attackers, leaving a team with fewer offensive weapons.

Another aspect is to see the setter as an attacking force, albeit a weakened force, because when the setter is in the front court they are able to 'tip' or 'dump', so when the ball is close to the net on the second touch, the setter may opt to hit the ball over with one hand. This means that the blocker who would otherwise not have to block the setter is engaged and may allow one of the hitters to have an easier attack.

6-2In the 6-2 formation, a player always comes forward from the back row to set. The three front row players are all in attacking positions. Thus, all six players act as hitters at one time or another, while two can act as setters. So the 6-2 formation is actually a 4-2 system, but the back-row setter penetrates to set.

The 6-2 lineup thus requires two setters, who line up opposite to each other in the rotation. In addition to the setters, a typical lineup will have two middle hitters and two outside hitters. By aligning like positions opposite themselves in the rotation, there will always be one of each position in the front and back rows. After service, the players in the front row move into their assigned positions.

The advantage of the 6-2 is that there are always three front-row hitters available, maximizing the offensive possibilities. However, not only does the 6-2 require a team to possess two people capable of performing the highly specialized role of setter, it also requires both of those players to be effective offensive hitters when not in the setter position. At the international level, only the Cuban National Women's Team employs this kind of formation. It is also used in Women's NCAA play, partially due to the variant rules used which allow 12 substitutions per set (as opposed to the 6 allowed in the standard rules).

5-1The 5-1 formation has only one player who assumes setting responsibilities regardless of his or her position in the rotation. The team will therefore have three front-row attackers when the setter is in the back row, and only two when the setter is in the front row, for a total of five possible attackers.

The player opposite the setter in a 5-1 rotation is called the opposite hitter. In general, opposite hitters do not pass; they stand behind their teammates when the opponent is serving. The opposite hitter may be used as a third attack option (back-row attack) when the setter is in the front row: this is the normal option used to increase the attack capabilities of modern volleyball teams. Normally the opposite hitter is the most technical skilled hitter of the team. Back-row attacks generally come from the back-right position,known as zone 1, but are increasingly performed from back-center in high-level play.

The big advantage of this system is that the setter always has 3 hitters to vary sets with. If the setter does this well, the opponent's middle blocker may not have enough time to block with the outside blocker, increasing the chance for the attacking team to make a point.

There is another advantage, the same as that of a 4-2 formation: when the setter is a front-row player, he or she is allowed to jump and "dump" the ball onto the opponent's side. This too can confuse the opponent's blocking players: the setter can jump and dump or can set to one of the hitters. A good setter knows this and thus won't only jump to dump or to set for a quick hit, but when setting outside as well to confuse the opponent.

The 5-1 offense is actually a mix of 6-2 and 4-2: when the setter is in the front row, the offense looks like a 4-2; when the setter is in the back row, the offense looks like a 6-2.

Variations and related gamesMain article: Volleyball variations
There are many variations on the basic rules of volleyball. By far the most popular of these is beach volleyball, which is played on sand with two people per team, and rivals the main sport in popularity.

Some games related to volleyball include:

Footvolley: A sport from Brazil in which the hands and arms are not used but most else is like beach volleyball.
Hooverball: Popularized by President Herbert Hoover, it is played with a volleyball net and a medicine ball; it is scored like tennis, but the ball is caught and then thrown back. The weight of the medicine ball can make the sport to be quite physically demanding; annual championship tournaments are held annually in West Branch, Iowa.
Newcomb ball (sometimes spelled "Nuke 'Em"): In this game, the ball is caught and thrown instead of hit; it rivaled volleyball in popularity until the 1920s.
Prisoner Ball: Also played with volleyball court and a volleyball, the object of the game is to get your opponents "out".
Throwball became popular with women players at the YMCA College of Physical Education in Chennai (India) in the 1940s.
Buka ball: This is a rather similar game played only with the feet.

วันเสาร์ที่ 19 กุมภาพันธ์ พ.ศ. 2554

Pineapple


Pineapple (Ananas comosus) is the common name for a tropical plant and its edible fruit which are coalesced berries. Pineapples are the only bromeliad fruit in widespread cultivation. It can be grown as an ornamental, especially from the leafy tops. Some sources say that the plant will flower after about 24 months & produce a fruit during the following six months while others indicate a 20-month timetable.
Pineapple is eaten fresh or canned or juiced. It is popularly used in desserts, salads, as a complement to meat dishes and in fruit cocktail. The popularity of the pineapple is due to its sweet-sour taste containing 15% sugar and malic and citric fruit acids. It is also high in vitamin B1, B2, B6 and C. Its protein-digesting enzyme bromelain seems to help digestion at the end of a high protein meal.
In the Philippines, pineapple leaves are used as the source of a textile fiber called piña.


Etymology


The word pineapple in English was first recorded in 1398, when it was originally used to describe the reproductive organs of conifer trees (now termed pine cones). The term pine cone for the reproductive organ of conifer trees was first recorded in 1694. When European explorers discovered this tropical fruit, they called them pineapples (term first recorded in that sense in 1664 because of their resemblance to what is now known as the pine cone).
In the scientific binomial Ananas comosus, ananas, the original name of the fruit, comes from the Tupi (Rio de Janeiro, Brazil) word nanas, meaning "excellent fruit",as recorded by André Thevet in 1555, and comosus, "tufted", refers to the stem of the fruit. Other members of the Ananas genus are often called pine as well by laymen.
Many languages use the Tupian term ananas. In Spanish, pineapples are called piña "pine cone" in Spain and most Hispanic American countries, or ananá (ananás in Argentina) (see the piña colada drink). They have varying names in the languages of India: "Anaasa" (అనాస) in Telugu, "Sapuri-PaNasa" (ସପୁରି ପଣସ) in Odia language,annachi pazham (Tamil), anarosh (Bengali), and in Malayalam, kaitha chakka. In Malay, pineapples are known as "nanas" or "nenas". In the Maldivian language of Dhivehi, pineapples are known as alanaasi. A large, sweet pineapple grown especially in Brazil is called abacaxi .


Botany


The pineapple is a herbaceous short-lived perennial plant which grows to 1.0 to 1.5 metres (3.3 to 4.9 ft) tall. After the first fruit is produced, side shoots (called 'suckers' by commercial growers) are produced in the leaf axils of the main stem. These may be removed for propagation, or left to produce additional fruits on the original plant.Commercially, suckers that appear around the base are cultivated. It has 30 or more long, narrow, fleshy, trough-shaped leaves with sharp spines along the margins that are 30 to 100 centimetres (1.0 to 3.3 ft) long, surrounding a thick stem. In the first year of growth the axis lengthens and thickens, bearing numerous leaves in close spirals. After 12 to 20 months the stem grows into a spike-like inflorescence up to 15 cm long with over 100 spirally arranged, trimerous flowers, each subtended by a bract. Flower colours vary, depending on variety, from lavender, through light purple to red.
The ovaries develop into berries which coalesce into a large, compact, multiple accessory fruit. The fruit of a pineapple is arranged in two interlocking helices, eight in one direction, thirteen in the other, each being a Fibonacci number.
Pineapple carries out CAM photosynthesis, fixing carbon dioxide at night and storing it as the acid malate and then releasing it during the day, aiding photosynthesis.


Pollination


Pollination is required for seed formation, but the presence of seeds negatively affects the quality of the fruit. In Hawaii, where pineapple is cultivated on an agricultural scale, importation of hummingbirds is prohibited for this reason. Certain bat-pollinated wild pineapples only open their flowers at night.


Nutrition


Raw pineapple is an excellent source of manganese (45% DV in a 100 g serving) and vitamin C (80% DV per 100 g).
Pineapple contains a proteolytic enzyme, bromelain, which breaks down protein. Pineapple juice can thus be used as a marinade and tenderizer for meat. The enzymes in raw pineapples can interfere with the preparation of some foods, such as jelly or other gelatin-based desserts, but it is destroyed during cooking and the canning process. The quantity of bromelain in the fruit is probably not medically significant, being mostly in the inedible stalk.
Folk medicine
There are myths that pineapple has benefits for intestinal disorders[citation needed] or serves as a pain reliever.


Distribution


The plant is indigenous to South America, though little is known about the origin of the domesticated pineapple (Pickersgill, 1976). M.S. Bertoni (1919) considered the ParanaParaguay river drainages to be the place of origin of A. comosus.The natives of southern Brazil and Paraguay spread the pineapple throughout South America, and it eventually reached the Caribbean. Columbus discovered it in the Indies and brought it back with him to Europe.[ The Spanish introduced it into the Philippines, Hawaii (introduced in the early 19th century, first commercial plantation 1886), Zimbabwe and Guam. The fruit was cultivated successfully in European hothouses, and pineapple pits, beginning in 1720.
The pineapple was introduced to Hawaii in 1813; exports of canned pineapples began in 1892. Large scale pineapple cultivation by U.S. companies began in the early 1900s on Hawaii. Among the most famous and influential pineapple industrialists was James Dole, who started a pineapple plantation in Hawaii in the year 1900. The companies Dole and Del Monte began growing pineapple on the island of Oahu in 1901 and 1917, respectively. Maui Pineapple Company began pineapple cultivation on the island of Maui in 1909. In 2006, Del Monte announced its withdrawal from pineapple cultivation in Hawaii, leaving only Dole and Maui Pineapple Company in Hawaii as the USA’s largest growers of pineapples. Maui Pineapple Company markets its Maui Gold brand of pineapple and Dole markets its Hawaii Gold brand of pineapple.
In the USA in 1986, the Pineapple Research Institute was dissolved and its assets were divided between Del Monte and Maui Land and Pineapple. Del Monte took variety 73-114, which it dubbed MD-2, to its plantations in Costa Rica, found it to be well-suited to growing there, and launched it publicly in 1996. (Del Monte also began marketing 73-50, dubbed CO-2, as Del Monte Gold). In 1997, Del Monte began marketing its Gold Extra Sweet pineapple, known internally as MD-2. MD-2 is a hybrid that originated in the breeding program of the now-defunct Pineapple Research Institute in Hawaii, which conducted research on behalf of Del Monte, Maui Land & Pineapple Company, and Dole.


Cultivation


Southeast Asia dominates world production: in 2001 Thailand produced 1.979 million tons and the Philippines 1.618 million tons, while in the Americas Brazil produced 1.43 million tons. Total world production in 2001 was 14.220 million tons. The primary exporters of fresh pineapples in 2001 were Costa Rica, 322,000 tons; Côte d'Ivoire, 188,000 tons; and the Philippines, 135,000 tons.

Since about 2000, the most common fresh pineapple fruit found in U.S. and European supermarkets is a low-acid hybrid that was developed in Hawaii in the early 1970s.
In commercial farming, flowering can be induced artificially, and the early harvesting of the main fruit can encourage the development of a second crop of smaller fruits. Once removed during cleaning, the top of the pineapple can be planted in soil and a new plant will grow. Slips and suckers are planted commercially.
Cultivars
There are many cultivars. The leaves of the commonly grown 'Smooth Cayenne' are smooth.and is the most commonly grown world wide. Many cultivars have become distributed from its origins in Paraguay and the southern part of Brazil.and later improved stocks were introduced into the Americas, the Azores, Africa, India, Malaysia and Australia. Varieties include:
'Hilo': A compact 1–1.5 kg (2-3 lb) Hawaiian variant of 'Smooth Cayenne'. The fruit is more cylindrical and produces many suckers but no slips.
'Kona Sugarloaf': 2.5–3 kg (5-6 lb), white flesh with no woodiness in the center. Cylindrical in shape, it has a high sugar content but no acid. An unusually sweet fruit.
'Natal Queen': 1–1.5 kg (2-3 lb), golden yellow flesh, crisp texture and delicate mild flavor. Well adapted to fresh consumption. Keeps well after ripening. Leaves spiny. Grown in Australia, Malaysia, and South Africa.

'Pernambuco' ('Eleuthera'): 1–2 kg (2-4 lb) with pale yellow to white flesh. Sweet, melting and excellent for eating fresh. Poorly adapted for shipping. Leaves spiny.Grown in Latin America
'Red Spanish': 1–2 kg (2-4 lb), pale yellow flesh with pleasant aroma; squarish in shape. Well adapted for shipping as fresh fruit to distant markets. Leaves spiny. Grown in Latin America
'Smooth Cayenne': 2.5–3 kg (5-6 lb), pale yellow to yellow flesh. Cylindrical in shape and with high sugar and acid content. Well adapted to canning and processing. Leaves without spines. This is the variety from Hawaii, and the most easily obtainable in U.S. grocery stores. Both 73-114 and 73-50 are of this cultivar.


Cantaloupe


Cantaloupe (also cantaloup, mushmelon, muskmelon, cantalope, rockmelon or spanspek) refers to a variety of Cucumis melo, a species in the family Cucurbitaceae which includes nearly all melons and squashes. Cantaloupes range in size from 0.5 kg to 5.0 kg. Originally, cantaloupe referred only to the non-netted orange-fleshed melons of Europe; however, in more recent usage it has come to mean any orange-fleshed melon (C. melo).


Cantaloupes by region


The European cantaloupe is lightly ribbed, with a gray-green skin that looks quite different from that of the North American cantaloupe.

The North American cantaloupe, common in the United States, Mexico, and in some parts of Canada, has a net-like (or reticulated) skin covering. It is a round melon with firm, orange, moderately sweet flesh and a thin reticulated light-brown rind. Varieties with redder and yellower flesh exist but are not common in the U.S market.


Origin


The cantaloupe originated in India and Africa.
Cantaloupes were originally cultivated by the Egyptians and later the Greeks and Romans.
Cantaloupes were first introduced to North America by Christopher Columbus on his second voyage to the New World in 1494. The W. Atlee Burpee Company developed and introduced the "Netted Gem" in 1881 from varieties then growing in North America.


Production and uses


Because they are descended from tropical plants, and tend to require warm temperatures throughout a relatively long growing period, cantaloupes grown in temperate climates are frequently started indoors, and grown indoors for 14 days or longer, before being transplanted outdoors.
Cantaloupe are often picked, and shipped, before fully ripening. Post-harvest practices include treatment with a sodium hypochlorite wash to prevent mold growth and Salmonella growth. This treatment, because it can mask the melon's musky aroma, can make it difficult for the purchaser to judge the relative quality of different cantaloupes.
Choosing a ripe melon depends on the preferences of the individual. For a heavy musk flavor and softer flesh, look for an Eastern Shipper with a strong yellow color, no stem (peduncle) attached, and a strong musk aroma. For a sweeter, crisper melon look for a Western Shipper without stem (peduncle) and a mild musk odor. For a very sweet melon with little or no musk, choose a fruit that has the stem still on the fruit and no aroma.
Cantaloupe is normally eaten as a fresh fruit, as a salad, or as a dessert with ice cream or custard. Melon pieces wrapped in prosciutto are a familiar antipasto.
Because the surface of a cantaloupe can contain harmful bacteria—in particular, Salmonella it is always a good idea to wash a melon thoroughly before cutting and consumption. Only store the fruit for less than three days after cutting to prevent risk of Salmonella or other bacterial pathogens.
A moldy cantaloupe in a Peoria, Illinois market in 1941 was found to contain the best and highest quality penicillin, after a worldwide search.


Mango


Mango is a fruit which is indigenous to the Indian subcontinent,belonging to the genus Mangifera, consisting of numerous species of tropical fruiting trees in the flowering plant family Anacardiaceae. While other Mangifera species (e.g. horse mango, M. foetida) are also grown on a more localized basis, Mangifera indica – the common mango or Indian mango – is the only mango tree commonly cultivated in many tropical and subtropical regions, and its fruit is distributed essentially world-wide.
In several cultures, its fruit and leaves are ritually used as floral decorations at weddings, public celebrations and religious ceremonies.


Etymology


The English word "mango" probably originated from the Tamil word maangai (மாங்காய்), then via Malayalam to Portuguese as manga.The word's first recorded attestation in a European language was a text by Ludovico di Varthema in Italian in 1510, as manga; the first recorded occurrences in languages such as French and post-classical Latin appear to be translations from this Italian text. The origin of the "-o" ending in English is unclear.
When mangoes were first imported to the American colonies in the 17th century, they had to be pickled due to lack of refrigeration. Other fruits were also pickled and came to be called "mangoes" (especially bell peppers), and by the 18th century, the word "mango" became a verb meaning "to pickle".In Oriya Mango is known as Aamba


Description


Mango trees (Mangifera indica L.) grow upto 35–40 m (115–130 ft) tall, with a crown radius of 10 m (33 ft). The mango tree is long-lived, as some specimens still fruit after 300 years.[citation needed] In deep soil, the taproot descends to a depth of 6 m (20 ft) and the profuse, wide-spreading feeder roots also send down many anchor roots, which penetrate several feet of soil. The leaves are evergreen, alternate, simple, 15–35 cm (5.9–14 in) long and 6–16 cm (2.4–6.3 in) broad; when the leaves are young they are orange-pink, rapidly changing to a dark glossy red, then dark green as they mature. The flowers are produced in terminal panicles 10–40 cm (3.9–16 in) long; each flower is small and white with five petals 5–10 mm (0.20–0.39 in) long, with a mild sweet odor suggestive of lily of the valley. The fruit takes three to six months to ripen.
The ripe fruit is variable in size and color. Cultivars are variously yellow, orange, red or green, and carry a single flat, oblong pit that can be fibrous or hairy on the surface, and which does not separate easily from the pulp. Ripe, unpeeled fruit gives off a distinctive resinous, sweet smell. Inside the pit 1–2 mm (0.039–0.079 in) thick is a thin lining covering a single seed, 4–7 mm (0.16–0.28 in) long. The seed contains the plant embryo.


Cultivation and uses


Mangoes have been cultivated in the Indian subcontinent for thousands of years and reached East Asia between the 5th and 4th centuries BC. By the 10th century AD, cultivation had begun in East Africa.The 14th century Moroccan traveler, Ibn Battuta, reported it at Mogadishu.Cultivation came later to Brazil, the West Indies and Mexico, where an appropriate climate allows its growth.
Mango is now cultivated in most frost-free tropical and warmer subtropical climates; nearly half of the world's mangoes are cultivated in India alone.
Mango is also being grown in Andalusia, Spain (mainly in Málaga province), which is one of the few places in mainland Europe that allows growth of tropical plants and fruit trees. Many of the 1,000 + mango cultivars are easily cultivated using grafted saplings, ranging from the "turpentine mango" (named for its strong taste of turpentine, which according to the Oxford Companion to Food some varieties actually contain) to the huevos de toro ("eggs of the bull", a euphemism for "bull's testicles", referring to the shape and size).
Other cultivators include North, South and Central America, the Caribbean, south, west and central Africa, Australia, China, Pakistan, Bangladesh, and Southeast Asia.
Though India is the largest producer of mangoes, it accounts for less than one percent of the international mango trade, consuming most of its own output.
Dwarf or semi-dwarf varieties serve as ornamental plants and can be grown in containers.
A wide variety of diseases can afflict mangoes; see List of mango diseases.


Potential for contact dermatitis


Mango peel contains urushiol, the chemical in poison ivy and poison sumac that can cause urushiol-induced contact dermatitis in susceptible people. Cross-reactions between mango contact allergens and urushiol have been observed.Those with a history of poison ivy or poison oak contact dermatitis may be most at risk for such an allergic reaction. Urushiol is also present in mango leaves and stems. During mango's primary ripening season, it is the most common source of plant dermatitis in Hawaii.


Food


Mango is generally sweet, although the taste and texture of the flesh varies across cultivars, some having a soft, pulpy texture similar to an overripe plum, while the flesh of others is firmer, like a cantaloupe or avocado, or may have a fibrous texture. For consumption of unripe, pickled or cooked fruit, the mango skin may be consumed comfortably, but has potential to cause contact dermatitis (above) of the lips, gingiva or tongue in susceptible people. In ripe fruits which are commonly eaten fresh, the skin may be thicker and bitter tasting, so is typically not eaten.


Cuisine


Mangoes are widely used in cuisine. Sour, unripe mangoes are used in chutneys, athanu, pickles, or side dishes, or may be eaten raw with salt, chili, or soy sauce. A cooling summer drink called panna or panha comes from mangoes.
Ripe mangoes are typically eaten fresh; however, they can have many other culinary uses. Mango Lassi, a popular drink made throughout South Asia[citation needed], is created by mixing ripe mangoes or mango pulp with yogurt and sugar. Ripe mangoes are also used to make curries. Aamras is a popular pulp/thick juice made of mangoes with sugar or milk, and is consumed with bread.
Mangoes are used in preserves like moramba, amchur (dried and powdered unripe mango) and pickles, including a spicy mustard-oil pickle. Ripe mangoes are often cut into thin layers, desiccated, folded, and then cut. These bars are similar to dried guava fruit bars available in some countries. The fruit is also added to cereal products like muesli and oat granola.


Unripe mango may be eaten with bagoong (especially in the Philippines), fish sauce or with dash of salt. Dried strips of sweet, ripe mango (sometimes combined with seedless tamarind to form mangorind) are also popular. Mangoes may be used to make juices, mango nectar, and as a flavoring and major ingredient in ice cream and sorbetes.
Mango is used to make juices, smoothies, ice cream, fruit bars, raspados, aguas frescas, pies and sweet chili sauce, or mixed with chamoy, a sweet and spicy chili paste. It is popular on a stick dipped in hot chili powder and salt or also as a main ingredient in fresh fruit combinations. In Central America, mango is either eaten green mixed with salt, vinegar, black pepper and hot sauce, or ripe in various forms. Toasted and ground pumpkin seed (called pepita) with lime and salt are the norm when eating green mangoes. Some people also add soy sauce or chili sauce.
Pieces of mango can be mashed and used as a topping on ice cream or blended with milk and ice as milkshakes. Sweet glutinous rice is flavored with coconut, then served with sliced mango as a dessert. In other parts of Southeast Asia, mangoes are pickled with fish sauce and rice vinegar. Green mangoes can be used in mango salad with fish sauce and dried shrimp. Mango with condensed milk may be used as a topping for shaved ice.


Nutrients and phytochemicals


Mango is rich in a variety of phytochemicals and nutrients. The fruit pulp is high in prebiotic dietary fiber, vitamin C, diverse polyphenols and provitamin A carotenoids.
Mango contains essential vitamins and dietary minerals. The antioxidant vitamins A, C and E compose 25%, 76% and 9% of the Dietary Reference Intake (DRI) in a 165 grams (5.8 oz) serving. Vitamin B6 (pyridoxine, 11% DRI), vitamin K (9% DRI), other B vitamins and essential nutrients, such as potassium, copper and 17 amino acids are at good levels. Mango peel and pulp contain other phytonutrients, such as the pigment antioxidants – carotenoids and polyphenols – and omega-3 and -6 polyunsaturated fatty acids.<>
Mango peel contains pigments that may have antioxidant properties, including carotenoids, such as the provitamin A compound, beta-carotene, lutein and alpha-carotene, polyphenolssuch as quercetin, kaempferol, gallic acid, caffeic acid, catechins, tannins, and the unique mango xanthonoid, mangiferin, any of which may counteract free radicals in various disease processes as revealed in preliminary research.Phytochemical and nutrient content appears to vary across mango species.Up to 25 different carotenoids have been isolated from mango pulp, the densest of which was beta-carotene, which accounts for the yellow-orange pigmentation of most mango species. Peel and leaves also have significant polyphenol content, including xanthonoids, mangiferin and gallic acid.
The mango triterpene, lupeol,[28] is an effective inhibitor in laboratory models of prostate and skin cancers. An extract of mango branch bark called Vimang, isolated by Cuban scientists, contains numerous polyphenols with antioxidant properties in vitroand on blood parameters of elderly humans.
The pigment euxanthin, known as Indian yellow, is often thought to be produced from the urine of cattle fed mango leaves; the practice is described as having been outlawed in 1908 due to malnutrition of the cows and possible urushiol poisoning. This supposed origin of euxanthin appears to rely on a single, anecdotal source, and Indian legal records do not outlaw such a practice.

Watermelon


Watermelon (Citrullus lanatus (Thunb.), family Cucurbitaceae) can be both the fruit and the plant of a vine-like (scrambler and trailer) plant originally from southern Africa, and is one of the most common types of melon. This flowering plant produces a special type of fruit known by botanists as a pepo, a berry which has a thick rind (exocarp) and fleshy center (mesocarp and endocarp); pepos are derived from an inferior ovary, and are characteristic of the Cucurbitaceae. The watermelon fruit, loosely considered a type of melon (although not in the genus Cucumis), has a smooth exterior rind (green, yellow and sometimes white) and a juicy, sweet interior flesh (usually pink, but sometimes orange, yellow, red and sometimes green if not ripe). It is also commonly used to make a variety of salads, most notably fruit salad


History


Watermelon is thought to have originated in southern Africa, where it is found growing wild, because it reaches maximum genetic diversity there, resulting in sweet, bland and bitter forms. Alphonse de Candolle, in 1882,already considered the evidence sufficient to prove that watermelon was indigenous to tropical Africa.Though Citrullus colocynthis is often considered to be a wild ancestor of watermelon and is now found native in north and west Africa, Fenny Dane and Jiarong Liu suggest on the basis of chloroplast DNA investigations that the cultivated and wild watermelon appear to have diverged independently from a common ancestor, possibly C. ecirrhosus from Namibia.


It is not known when the plant was first cultivated, but Zohary and Hopf note evidence of its cultivation in the Nile Valley from at least as early as the second millennium BC. Although watermelon is not depicted in any Egyptian hieroglyphic text nor does any ancient writer mention it, finds of the characteristically large seed are reported in Twelfth dynasty sites; numerous watermelon seeds were recovered from the tomb of Pharaoh Tutankhamun.


By the 10th century AD, watermelons were being cultivated in China, which is today the world's single largest watermelon producer. By the 13th century, Moorish invaders had introduced the fruit to Europe; according to John Mariani's The Dictionary of American Food and Drink, "watermelon" made its first appearance in an English dictionary in 1615.


Museums Online South Africa list watermelons as having been introduced to Native Americans in the 16th century. Early French explorers found Native Americans cultivating the fruit in the Mississippi Valley. Many sources list the watermelon as being introduced in Massachusetts as early as 1629. Southern food historian John Egerton has said he believes African slaves helped introduce the watermelon to the United States. Texas Agricultural Extension horticulturalist Jerry Parsons lists African slaves and European colonists as having distributed watermelons to many areas of the world. Parsons also mentions the crop being farmed by Native Americans in Florida (by 1664) and the Colorado River area (by 1799). Other early watermelon sightings include the Midwestern states (1673), Connecticut (1747) and the Illiana region (1822).


Charles Fredric Andrus, a horticulturist at the USDA Vegetable Breeding Laboratory in Charleston, South Carolina, set out to produce a disease-resistant and wilt-resistant watermelon. The result was "that gray melon from Charleston." Its oblong shape and hard rind made it easy to stack and ship. Its adaptability meant it could be grown over a wide geographical area. It produced high yields and was resistant to the most serious watermelon diseases: anthracnose and fusarium wilt.


Today, farmers in approximately 44 states in the U.S. grow watermelon commercially, and almost all these varieties have some Charleston Gray in their lineage. Georgia, Florida, Texas, California and Arizona are the USA's largest watermelon producers.


This now-common watermelon is often large enough that groceries often sell half or quarter melons. There are also some smaller, spherical varieties of watermelon, both red- and yellow-fleshed, sometimes called "icebox melons."


In Japan, farmers of the Zentsuji region found a way to grow cubic watermelons, by growing the fruits in glass boxes and letting them naturally assume the shape of the receptacle. The square shape is designed to make the melons easier to stack and store, but the square watermelons are often more than double the price of normal ones. Pyramid shaped watermelons have also been developed and any polyhedral shape may potentially also be used.


Culture


For commercial plantings, one beehive per acre (4,000 m² per hive) is the minimum recommendation by the US Department of Agriculture for pollination of conventional, seeded varieties. Because seedless hybrids have sterile pollen, pollinizer rows of varieties with viable pollen must also be planted. Since the supply of viable pollen is reduced and pollination is much more critical in producing the seedless variety, the recommended number of hives per acre, or pollinator density, increases to three hives per acre (1,300 m² per hive).


Nutrition


A watermelon contains about 6% sugar and 92% water by weight. As with many other fruits, it is a source of vitamin C.


Notable is the inner rind of the watermelon, which is usually a light green or white color. This area is edible and contains many hidden nutrients that most people avoid eating due to its unappealing flavor.


The amino acid citrulline was first extracted from watermelon and analysed.Watermelons contain a significant amount of citrulline and after consumption of several kg, an elevated concentration is measured in the blood plasma; this could be mistaken for citrullinaemia or other urea cycle disorders.


Watermelon rinds are also edible, and sometimes used as a vegetable. In China, they are stir-fried, stewed or more often pickled. When stir-fried, the de-skinned and de-fruited rind is cooked with olive oil, garlic, chili peppers, scallions, sugar and rum. Pickled watermelon rind is also commonly consumed in the Southern US.Watermelon juice can also be made into wine.


Watermelon is also mildly diuretic.
Watermelons contain large amounts of
beta carotene.
Watermelon with red flesh is a significant source of
lycopene.


Varieties


There are more than 1200 varieties of watermelon ranging in size from less than a pound, to more than two hundred pounds, with flesh that is red, orange, yellow or white. Several notable varieties are included here.
Carolina Cross: This variety of watermelon produced the current world record watermelon weighing 262 pounds (119 kg). It has green skin, red flesh and commonly produces fruit between 65 and 150 pounds (29 and 68 kg). It takes about 90 days from planting to harvest.
Yellow Crimson Watermelon: variety of watermelon that has a yellow colored flesh. This particular type of watermelon has been described as "sweeter" and more "honey" flavored than the more popular red flesh watermelon.
Orangeglo: This variety has a very sweet orange pulp, and is a large oblong fruit weighing 9–14 kg (20–30 pounds). It has a light green rind with jagged dark green stripes. It takes about 90–100 days from planting to harvest.
The Moon and Stars variety of watermelon has been around since 1926. The rind is purple/black and has many small yellow circles (stars) and one or two large yellow circles (moon). The melon weighs 9–23 kg (20–50 pounds). The flesh is pink or red and has brown seeds. The foliage is also spotted. The time from planting to harvest is about 90 days.
Cream of Saskatchewan: This variety consists of small round fruits, around 25 cm (10 inches) in diameter. It has a quite thin, light green with dark green striped rind, with sweet white flesh and black seeds. It can grow well in cool climates. It was originally brought to
Saskatchewan, Canada by Russian immigrants. These melons take 80–85 days from planting to harvest.
Melitopolski: This variety has small round fruits roughly 28–30 cm (11–12 inches) in diameter. It is an early ripening variety that originated from the
Volga River region of Russia, an area known for cultivation of watermelons. The Melitopolski watermelons are seen piled high by vendors in Moscow in summer. This variety takes around 95 days from planting to harvest.
Densuke Watermelon: This variety has round fruit up to 25 lb (11 kg). The rind is black with no stripes or spots. It is only grown on the island of Hokkaido, Japan, where up to 10 000 watermelons are produced every year. In June 2008, one of the first harvested watermelons was sold at an auction for 650 000 yen (6300 USD), making the most expensive watermelon ever sold. The average selling price is generally around 25 000 yen (250 USD).


Cultural uses and references



In Vietnamese culture, watermelon seeds are consumed during the Vietnamese New Year's holiday, Tết, as a snack.
Stereotypical
caricatures may depict African Americans as being inordinately fond of watermelon.
The
Oklahoma State Senate passed a bill on 17 April 2007 declaring watermelon as the official state vegetable, with some controversy surrounding whether a watermelon is a fruit.
The
citrulline which exists in watermelon (especially in the rind) is a known stimulator of nitric oxide. Nitric oxide is thought to relax and expand blood vessels, much like the erectile dysfunction drug Viagra, and may even increase libido.
Fans of the
Saskatchewan Roughriders of the CFL started a tradition of hollowing out a watermelon and wearing it as a makeshift football helmet (the color of the Roughriders is green). During the 2009 Grey Cup in Calgary (between the Montreal Alouettes and the Roughriders), thousands of watermelons had to be imported to Calgary supermarkets to prevent a shortage being caused by Rider fans.
The town of
Chinchilla in Queensland, Australia holds a biannual festival celebrating all things melon.
The
Ten-lined June beetle is often affectionately referred to as a Watermelon Beetle, due to the green, striped pattern on its back.