Effect of Spray Application of Calcium Compounds Combined with Free Polyamines at Different Growth Stages on Physiological Problems and Yield of  Ahmad-Aghaii Pistachio (Pistacia vera L.)

Pistachio is one of most important horticultural crops in Iran, USA, Turkey and some Mediterranean countries. Some physiological problems such as abscission of inflorescence buds, blankness, non-splitting, early splitting, cracking and nut deformation reduce the pistachio yield and quality.
This experiment were carried out in a commercial 20-year old ‘Ahmad-Aghaii’ pistachio orchard in Rafsanjan, Iran. It was arranged as factorial based on randomized completely block design with three replications.
Results showed that the main physiological problems of pistachio crop were decreased by application of calcium compounds combined with free polyamines. Spray application of the mentioned treatments was more effective at combined stages of 1 and 2 rather than the stages separately. It was resulted that calcium nitrate combined with spermine and spermidine treatments at combined stages of 1 and 2 reduced the abscission of inflorescence buds, blankness, nut deformation and non-splitting. Also, it was found that calcium nitrate combined with spermidine at combined stages of 1 and 2 reduced the percentage of early splitting while splitting and yield were increased.