The Dragon Fruit or Pitaya is the fruit of several cactus species, most importantly of the genus Hylocereus, which is also called sweet pitayas. These fruit are commonly known as dragon fruit, which is a translation from the Chinese name, huo long quo, literally meaning "fire dragon fruit" and long zhu guo "dragon pearl fruit", or Vietnamese thanh long (green dragon). Other vernacular names are strawberry pear or nanettikafruit. In Mauritius, it is known as "Débousse-to-fesse" because of its laxative properties.
Native to Mexico and Central and South America, the vine-like epiphytic Hylocereus cacti are also cultivated in Southeast Asian countries such as Taiwan, Vietnam, Thailand, the Philippines, Sri Lanka and Malaysia. They are also found in Okinawa, Hawaii, Israel, northern Australia and southern China. Hylocereus blooms only at night; the large white fragrant flowers of the typical cactusflower shape are among those called "moonflower" or "Queen of the Night". Sweet pitayas have a creamy pulp and a delicate aroma.
Hylocereus has adapted to live in dry tropical climates with a moderate amount of rain. The dragon fruit sets on the cactus-like trees 30 - 50 days after flowering and can sometimes have 5 - 6 cycles of harvests per year. There are some farms in Vietnam that produce 30 tons of fruit per hectare every year.
Overwatering or excessive rainfall can cause the flowers to drop and fruit to rot. Birds can be a nuisance. The bacterium Xanthomonas campestris causes the stems to rot. Dothiorella fungi can cause brown spots on the fruit, but this is not common.
There are three types of dragon fruits:
Hylocereus undatus (Red Pitaya) has red-skinned fruit with white flesh. This is the most commonly-seen "dragon fruit".
Hylocereus costaricensis (Costa Rica Pitaya, often called H. polyrhizus) has red-skinned fruit with red flesh.
Hylocereus megalanthus (Yellow Pitaya, formerly in Selenicereus) has yellow-skinned fruit with white flesh.
Dragon Fruit, also called Pitaya http://commons.wikimedia.org/wiki/File:Pitaya,_Hylocereus_polyrhizus,_Jun_07.JPG Sengkang
Dragon Fruit, also called Pitaya http://commons.wikimedia.org/wiki/File:Pitaya,_Hylocereus_polyrhizus_5,_Jun_07.JPG Sengkang
White-fleshed Dragon Fruit http://commons.wikimedia.org/wiki/File:Hylocereus_undatus_red_pitahaya.jpg T.Voekler
http://commons.wikimedia.org/wiki/File:Pitaya,_Hylocereus_polyrhizus,_Jun_07.JPG
Sengkang
