Vol. 9, Issue 10 (2020)

Author(s):
G Nissi Flora, J Dilip Babu, L Mukunda Lakshmi, DV Swami and Dr. Salomi Suneetha

Abstract:
Sweet orange fruit is one of the best commercial fruits of India. ‘Sathgudi’ is a cultivar cultivated on large area in the Andhra Pradesh due to its reasonably higher yield, quality, taste and flavor. However, its average yield is decreasing year by year due to change in climate. Fruit drop is one of the main reasons for low citrus fruit yield, which is thought to be mainly due to hormonal imbalance in the plants. This imbalance may occur as a result of nutrient deficiency in orchard soils, water shortage, and insect pest attack on the citrus trees. Therefore, experiments were conducted to assess the influence of growth regulators (2,4-D and GA₃ and nutrients potassium and urea] to improve yield and quality of sweet orange fruit and control the fruit drop at two selected sites in the citrus growing tract of Andhra Pradesh. Foliar applications of 2,4-D, GA₃, potassium and urea significantly improved and have the beneficial effects on physiological parameters and photosynthetic index like relative water content of leaf, stomatal density, rate of transpiration, stomatal conductance, rate of photosynthesis, water use efficiency and chlorophyll content.