GROWTH AND PRODUCTIVITY OF ACID LIME (CITRUS AURANTIFOLIA L.) AS AFFECTED BY SPRAYING GIBBERELLIC ACID

In order to study the effect of gibberellic acid concentration and frequencies of application on vegetative growth, leaves mineral content, yield, and fruit physical and chemical properties of acid lime trees (Citrus aurantifolia L), a field experiment was conducted in two successive seasons (2017 and 2018) at a private farm located at Derwa Village, Mallawy ElMinia Governorate, by using a randomized complete bloke design (RCBD). The obtained results confirmed that spraying with gibberellic acid at 10, 20, and 30 ppm significantly enhanced acid lime trees growth (shoot lengths, number of leaves/shoot, number of new shoots/tree, and leaf area), leaves chemical constituents (i.e. nitrogen%, potassium%, calcium%, and magnesium%), yield (kg)/tree and its component, as well as fruit physical and chemical properties (i.e. fruit dimension, TSS%, total acidity%, vitamin C (mg/100g F.W.)) compared to untreated trees. The maximum values in above mentioned parameters were observed in gibberellic acid treatment at 30 ppm three times, compared to the other ones and control treatment. However, non-significant differences were observed between the two higher concentrations (20 and 30 ppm). Generally, results of the present work demonstrated that application of gibberellic acid plays a remarkable role in improving growth parameters, leaves chemical composition, yield, and fruit physical and chemical properties of Balady acid lime trees under El-Minia Governorate conditions.