Evaluation the Effects of Foliar Treatments of Polyamines and Some Organic Acids on Quantitative and Qualitative Traits in Some Pistachio Cultivars

Abstract

Among the most important problems of pistachio are physiological disorders such as fruit abscission and production of blank nuts. Environmental stresses and inadequate nutrition during flowering time have increased these problems in recent years. In order to evaluate the effects of foliar treatments with polyamines and other compounds (amino acids and ascorbic acid) on quantitative and qualitative traits in pistachio cultivars, an investigation was conducted using a factorial experiment base on a completely randomized block design (CRBD) at an orchard condition in the Rafsanjan region. This experiment was performed to evaluate three factors, 1) type of treatment (spermine, spermidin, amino acids and ascorbic acid) at 6 concentrations, 2) cultivar (^،Ohadi^,, ^،Akbari^, and ^،Kalehghoochi^,) with three replications and 3) year (2013 and 2014). Different traits, such as yield per shoot, number of nuts per cluster, fruit abscission, blank nuts, split nuts, deformed nuts, length and diameter shoot were measured. The results indicated that all of the treatments increased yield and percentage of split, and decreased fruit abscission, blank and deformed nuts in comparison with the control. Spermine (1 mM) combined with ascorbic acid and amino acid, had the most significant effect, increasing yield 50 % and split nuts 18 % and also decreasing fruit abscission 20 %, and decreasing blank and deformed nuts 5 % in all cultivars, in comparison with controls. Ascorbic acid and amino acid treatment without polyamines had a lower effect in comparison with spermine treatment combined with these compounds. The combined use of these compounds, e.g., 1 mM spermine, ascorbic acid (0.5 g/L) and amino acids (3 g/L) suggests that they might act as a suitable compound fertilizer in order to reduce fruit abscission and increase the yield of pistachio crops without the impact of environmental pollution.