I. Overview
a. Pitaya is main planted at south Vietnam, Binh Thuan Province. Cultivated area is about 15,000 hectares which keeps increasing.
b. Binh Thuan Province approximate 10 degree north latitude. The climate is apparently distinguished rainy from dry season.
c. The principal cultivated line in Vietnam is white pulp pitaya. On the contrary, the red pulp pitaya line is just started to promote. However, the breeding goal is selecting self-compatibility and large fruit red pulp line.
d. The fruit is primary for export. The major markets are China, European Union and the United states.
II. Off-season production
a. Regulation strategy
1. Producing off-season (winter and spring) fruits.
2. Rising production especially late fruit season (approximate October to November).
b. Off-season production way
1. Illuminating 6-12 hours at one night.
2. Illumination for 15-25 days and adjustment according to season and plants nutrition condition.
i. about 15 days in autumn and spring
ii. about 25 days in winter
3. Incandescent lamp equipment is erected between two concrete pillars. After a cycle of illumination, devices are converted direction (south-north to east-west) and kept lighting.
4. There are as more as six illumination cycles if plants are under well condition. Ordinary orchards are processed about 2-3 cycles one year.
c. Incandescent lamp equipment
1. 60-75 watt incandescent lamp
2. 20 watt energy saving light bulb
3. Devices are established simplify but dangeously.
d. The features, advantages and disadvantages of off-season production in Vietnam.
1. Vietnam is located in low-latitude tropical zone. The requirements of plants and the day-length are readily coordinate.
2. When plants in well condition off-season production can easily process by way of illumination (adjusting photoperiod).
3. Large –scale cultivation with white pulp pitaya makes hand pollination not necessary and cost-down the tasks.
4. Off-season production happens to be dry season; therefore proper irrigation is a significant factor for flowering simultaneously.
5. There are still temporary low-temperature intervals in Vietnam winter. If off-season production will encounter low-temperature, illuminating time need to extend appropriately.
6. For producing most batch off-season fruits precise calculating every batch time of illuminating, flower bud initiating, and fruits maturing is necessary.
(Illuminating field )
(Illuminating field and Yi-Lu )
(Low-cost but dangerous equipment made with safety-pin simply.)
(Incandescent lamp were set on end and middle of shoots for promoting flower initiation. )
(Wires and lamps were supported by simple and crude branches.)
(After illuminating, all devices were recycled.)
(Plentiful flower buds had completed blossom in this well off-season production orchard.)
(Because of the high density of plants, there was only one side of shoots set fruits after lighting)
(Intensive density made two side of shoots different.
After lighting procedure, right side produced fruits but left side produces none.)
