Studies On Phenology And Methods For Increasing Fruit Setting Rate And Improving Quality Of Pistachio Vera.L

Recent years, we carried out pistachio introduction experiment and succeeded initially. Part of orchards started to bear fruit. However, there are some problems such as summer serious deseases, low fruit setting rate, bad quality fruits and so on. So the study was conducted to make clear the climate conditions, phenology (especially flowering phenology), fruit setting character, quality of the nuts and so on. Thus we carried out experiments about pollen storage, artificial pollination, supplementary nutrition on branches and so on in order to identify the constrain factors of pistachio yield and quality. All the studies can provide methods to improve fruit setting rate, yield and quality of pistachio. The results are as follows:1. The short branches and the south or east branches usually have a higher fruit rating than the other ones;2. Spraying the fertilizer before blooming period could obviously raise the bearing rate.3. The climate of Gangu is similar to the country of origin; the growing type of pistachio flowering buds shows type of "S" and the flower buds with a plumpness degree of 0.3 to0.4 has a high fruit setting rate;4. It is obvious that the male and female pistachio flowering periods can not meet; pollen vitality reach the highest at the end of full blom;5. Liquid powder with a concentration of 0.3% is the most suitable artificial pollination method in view of efficiency and effect;6. Pollen should be natural dried and put into ultra low temperature refrigerator for long term storage;7. Boric acid, AA, GA3 and NAA have influence on the pollen germination and tube growth of pistachio in varying degrees.