Effects of Plant Growth Regulators and Boron on Morpho-phenological Traits and Fruit Yield of Sponge Gourd (Luffa cylindrica L.)

Abstract

Sponge gourd (Luffa cylindrica L.) is an important cucurbitaceous vegetable crop valued for its tender fruits and diverse uses. A field experiment was conducted at the Research Farm, Department of Vegetable Science, CCS Haryana Agricultural University, Hisar, during the rainy season of 2022 to evaluate the effects of plant growth regulators and micronutrients on growth, flowering, and yield of sponge gourd cv. Pusa Chikni. The experiment comprised 15 treatments involving foliar applications of NAA at 50 and 100 ppm, ethrel at 100 and 150 ppm, borax at 0.05 and 0.10%, their selected combinations and a control. The treatments were applied at the 2- and 4-leaf stages and were arranged in a randomised block design with three replications. The data were subjected to ANOVA and treatment means were compared using the critical difference at the 5% level of significance. Growth and phenological traits, including the number of primary branches per vine, vine length, internodal distance, flowering behaviour, the number of nodes to the first male and female flowers, days to first fruit harvest, and fruit yield, were recorded. The application of ethrel at 150 ppm + borax at 0.05% produced 11.0 primary branches per vine, reduced internodal distance to 10.1 cm, advanced female flowering to 50.3 days, and resulted in the earliest fruit harvest at 60.7 days. This treatment also recorded the highest fruit yield of 140.3 q/ha, compared with 104.2 q/ha in the control. The results indicate that foliar application of ethrel with borax can improve flowering behaviour and yield performance of sponge gourd under the experimental conditions. However, the study was limited to a single season and location.