Effects of Different Organic and Inorganic Fertilizers on Growth and Yield of Cucumis anguria L.

Abstract

Declining soil fertility in Sri Lanka's dry zone necessitates the integration of organic manures with inorganic fertilizers for sustainable crop productivity. A pot experiment was conducted on sandy loam soil at the University Farm, Faculty of Agriculture, Eastern University, Sri Lanka, to evaluate the effects of different organic and inorganic fertilizers on the growth and yield of Cucumis anguria L. cv. Chandani. The experiment was laid out in a Completely Randomized Design with 13 treatments and 10 replicates. The treatments included T1 (100% inorganic fertilizer, control), T2-T4 (100% compost, cattle manure, and poultry manure), and T5-T13 (combinations of 75%, 50%, or 25% inorganic fertilizer with complementary organic manure) based on the recommended NPK rate of 150:75:100 kg/ha. Measurements were taken from 2 to 8 weeks after planting, and data were analyzed using one-way ANOVA with mean separation by Tukey's HSD at p<0.05. At 8 weeks after planting, T10 (50% inorganic fertilizer + 50% poultry manure) recorded the highest vine length (215.08 cm), leaf number (100.70), branch number (8.10), chlorophyll content (119.81 SPAD units), leaf area (4029.7 cm²), root length (166.98 cm), shoot dry weight (153.69 g), and root dry weight (16.896 g), along with the highest fruit yield (32.50 fruits/vine; 1.461 kg/vine; 14.61 t/ha) - a 174.62% increase over the control - and the highest net profit (Rs. 382,574.60/ha). Therefore, the 50:50 combination of inorganic fertilizer and poultry manure is recommended for profitable and environmentally friendly Cucumis anguria L. production in the dry zone of Sri Lanka.