Pruning and Chemical Manipulation Influence Leaf Physiological Parameters and Pod Yield Parameters of Perennial Moringa (Moringa oleifera Lam.) cv. Kappalpatti Local During Off-Season

Abstract

Understanding and controlling the physiological processes that regulate flowering is crucial for producing crops in off-season. To explore this, an experiment was conducted involving various pruning intensities and chemical sprays to induce off-season flowering and fruiting in moringa trees. The experiment followed a Factorial Randomized Block Design, with Factor I representing pruning at four levels: P-1 (No pruning), P-2 (Pinching off the previous year's growth of fruiting branches), P-3 (Light pruning, removing 33% of previous year's growth), and P-4 (Severe pruning, removing 66% of previous year's growth). Factor II involved chemical sprays at seven levels: C-1 (Control - water spray), C-2 to C-7 (Different chemical treatments). A total of 28 treatment combinations were tested with two replications each. Pruning was performed in the second week of July, and chemicals were sprayed twice, with the first application 30 days after pruning and the second 15 days thereafter. Various physiological parameters such as nitrate reductase activity, total carbohydrate content, nitrogen content, carbohydrate: nitrogen ratio, soluble protein, IAA oxidase activity, and gibberellic acid content in leaves were measured using standard procedures. Pod yield-related characteristics such as number of panicles per tree, number of flowers per panicle, number of pods per panicle, and total pod yield per tree were also recorded. Statistical analysis was conducted following Panse and Sukhatme's procedures (1985), revealing significant effects on various physiological parameters by pruning, chemicals, or their combinations. These alterations in physiological parameters induced flowering during the off-season in perennial moringa cv. Kappalpatti local. Notably, the interaction between pinching and foliar application of nitrobenzene at 0.5% (P2 × C7) resulted in 61.15 panicles per tree, while severe pruning combined with foliar application of  paclobutrazol at 50 ppm (P4 × C2) led to 125.45 flowers per panicle. Additionally, the interaction between light pruning and foliar application of paclobutrazol at 50 ppm (P3 × C2) showed significantly higher mean numbers of pods per panicle (2.95) and pod yield per tree (14.14 kg).