Influence of naphthalene acetic acid on fruit setting, fruit quality and yield of Manilkara achras L. cv. Kalipatti under subtropical conditions

Abstract

Manilkara achras L., commonly called sapota, is one of the major fruit crops commercially grown in India. Though India leads in world sapota production, the major problems in sapota are low fruit setting and yield. Hence, we studied these aspects in the commercially grown sapota cv. Kalipatti in Punjab conditions. The experiment was conducted to standardize the doses of naphthalene acetic acid (NAA) for fruit setting, quality and yield of sapota at Punjab Agricultural University, Ludhiana during 2016 and 2017. The results revealed that foliar application of 100 ppm NAA at flowering and pea stage during May flowering resulted in higher fruit setting (4.9%) and higher fruit retention (83.5%) over other treatments including control. Similarly, higher fruit setting (18.5%) and higher fruit retention (88.5%) and higher yield (75.90 kg/tree) were recorded in July-August flowering with foliar application of 100 ppm NAA. Fruit quality in terms of average fruit weight (104 g), TSS (22.50 ^oBrix) and acidity (0.20%) was also higher in 100 ppm NAA foliar application. Significantly lower PLW (7.56%) was also recorded in 100 ppm NAA treatment. Furthermore, it was observed that profuse flowering occurred during May, July and August months but the later flowering resulted in better crop. The study concluded that fruit setting, quality and yield in sapota cv. Kalipatti can be enhanced through foliar application of 100 ppm NAA at flowering and pea stage during July-August flowering under subtropical conditions.