Response of Pear Trees to Girdling and Foliar Spray with Naphthalene Acetic acid and Yeast Extract under the Conditions of New Valley

Abstract

A field experiment was carried out during 2020 and 2021 seasons on 8 years old early pear cultivar "Basateen MKM" trees grown in sandy soil under drip irrigation system at a private orchard on Al-Farafra road, Al-Wadi Al-Gadid governorate, Egypt. This study aimed to evaluate two levels of NAA foliar spray (15, and 30 ppm), two levels of yeast (0.4 and 0.6%) and girdling whether alone or with NAA and yeast and their effects on some vegetative growth characteristics, leaf mineral content as well as total yield and fruit quality. The obtained results showed that the combination of girdling and NAA at 15 ppm recorded the best results of total chlorophyll, fruit set %, total number of fruits/tree, yield, P,
K, Ca, Mg percentages, B at ppm, C/N ratio, also, physical and chemical fruit traits when compared with the untreated trees (water spray only). On the other hand, the same treatment reduced the leaf area, N%, and fruit firmness. In conclusion, combining girdling with other treatments improved the fruit quality. It increases the number of seeds, which may ameliorate fruit growth, facilitate the absorption of mineral elements, and affect the fruit size and chemical composition. Therefore, it concluded that the number of seeds in the fruits is considered one of the quality indicators of the early pear cultivar "Basateen MKM" under Al-Wadi Al-Gadid governorate conditions.