تاثير محلول پاشي برگي اوره ، در تركيب با بنزيل آدنين بمنظور كاهش ريزش جوانه گل در درختان پسته

Influence of Foliar Application of Urea Combined with 6-Benzyladenine to Decrease Flower Bud Abscission in Pistachio Nut

Alternate bearing in pistachio is the result of excessive abscission of the female floral bud during the on- year. So far no successful remedial treatment has been reported to prevent this process. The present research was carried out during 2000-1 growing seasons. The treatments were applied on two branches of each individual on-year trees. In the first year urea was applied at the rate of 0, 0.15%, 0.3% N and BA at the rate of 0, 25, 50 mgl^-1 and in the second year urea was applied at the rate of (0, 0.3%, 0.6% N) and BA at the rate of (0, 50, 100 mgl^-1) on branches of the `Owhadiʹ variety on- year trees. BA at 100 mgl^-1 alone and in combination with 0.6% N significantly increased floral bud retention. During the second year, 1.5-1.7 fold, in comparison to control, increase in floral bud retention was observed. A positive correlation (r=0.84*) was found between N content of bearing floral bud branches and floral bud retention (%), however, such relationship was not found between N content of leaf and flower bud retention. It can be postulated that N content of leaves might have been transferred to the other organs during the growing seasons. BA reduces kernel weight and increases blankness. A negative correlation was found between kernel weight and blankness in both years of the experiment.