Enhancing fruit set, yield and quality of LeConte pear trees by preharvest foliar spray of some plant growth regulators

Abstract

The present study was conducted during the two seasons 2021 and 2022 on eight-years-old of LeConte pear cultivar for enhancing fruit set, yield and quality by preharvest foliar spray of some plant growth regulators. Preharvest treatments included: control (spray with water only), nitrophenolate sodium (NPS) at 200 ppm, GA 4+7 at 10ppm, thidiazuron (TDZ) at 5ppm, NPS plus GA 4+7 , NPS plus TDZ and NPS plus GA 4+7 and TDZ. All preharvest foliar treatments were sprayed at full bloom and after fruit set with ten days. The results showed that treatment with 200 ppm of nitrophenolate sodium increased fruit set, fruit firmness, TSS and carotenes. Increases in shoot length, fruit pedicel length and diameter, fruit set, yield, and acidity were seen after treatment with GA 4+7 at 10 ppm. Carotenes and TSS in fruit were decreased. On the other hand, thidiazuron treatment at 5ppm increased pedicel fruit diameter, fruit set, yield, firmness, fruit diameter and acidity. Fruit TSS and carotenes were decreased.