Effect of supplementary pollination using enriched pollen suspension with Zn on fruit set and fruit quality of pistachio

- When pollination is a limiting factor in pistachio orchards, supplementary pollination using pollen suspension can be used commercially.
- Enrichment of pollen with zinc improved some fruit traits in pistachio trees.

The effect of pollen supplementation in pistachio using different suspension media (Control: Open pollination, S: 10% sucrose, A: 0.1% Agar, Zn1: 0.01% zinc sulfate, Zn2: 0.02% zinc sulfate, P: 0.1% Pollen) were investigated in two orchards (A and B). Yield (fruit set and fruit drop) and fruit quality (percent split fruit, nut blank, abnormal fruit and kernel mineral content) were tested based on a block complete randomize design with three replications. The results indicated that kernel dry weight and kernel fresh weight were affected by pollination treatments so that treatments of SAZn1P (10% sucrose + 0.1% agar + 0.01% zinc sulfate + 1 g/L pollen), SAZn2P (10% sucrose + 0.1% agar + 0.02% zinc sulfate + 1 g/L pollen) and SA (10% sucrose + 0.1% agar) decreased kernel fresh weight compared to the control. The results also showed that SAZn1P treatment increased nut thickness and nut split percentage in orchard 'B'. The highest final fruit set was obtained in orchard 'A' with SAZn2 treatment. According the results, when pollination is a limiting factor, supplementary pollination using enriched pollen suspension with Zn can improve yield and increase fruit quality.