Investigation on Effects of Calcium Nitrate, Calcium Sulfate (soil application) and Calcium chelate as Foliar spray on Endocarp Lesion Disorder and Some Qualitative Characteristics of pistachio nut Cv. Akbari

Calcium deficiency causes Endocarp Lesion disorder in pistachio nut. To investigate the effects of various calcium treatments on Endocarp Lesion disorder and some nut qualitative characteristics in Pistachio cv. Akbari, an experiment was done in completely randomized design with four treatments (- control treatment, 2- calcium chelate foliar spray, 3- calcium nitrate and 4– calcium sulfate (gypsum), calcium nitrate and calcium chelate foliar spray) in three replications in 2010. The results showed that the percentage of noncontaminated nuts and the percentage of contaminated nuts to mentioned disorder were significant (P <0.01). The most percentage of non-contaminated nuts and the least percentage of contaminated nuts were observed in three calcium treatments, but there was no significant difference between them. Qualitative characteristics of nut such as the percentage of splitting nuts, non-splitting nuts, small nuts and immature nuts were significant (P <0.01) but the percentage of blank nuts wasn’t significant. The most percentage of splitting nuts, the least percentage of non-splitting nuts and small nuts were obtained in gypsum, calcium nitrate and calcium foliar treatment (T4) and in calcium nitrate treatment (T3) respectively but there was no significant difference between two treatments. The least percentage of immature nuts was measured in gypsum, calcium nitrate and calcium foliar treatment (T4). The result of leaf nutrients amount measure (calcium, magnesium, sodium, calcium to magnesium ratio) showed magnesium was significant (P <0.05), sodium and calcium to magnesium ratio were significant level but amount of calcium was not significant. The least amount of magnesium and sodium and the most ratio of calcium to magnesium (Ca / Mg) in leaves were observed in gypsum, calcium nitrate and calcium foliar treatment (T4). High ratio of calcium to magnesium reduces magnesium poisoning and also the Endocarp Lesion. According to the results, application of gypsum, calcium nitrate and calcium foliar treatment (T4) can be more favorable than other treatments in reducing Endocarp Lesion disorder and improving nut quality in pistachio cv. Akbari