Response of Potassium Humate Extracted from Different Organic Sources on Yield and Quality of Green Chilli

Abstract

Aim: In recent trend of organic farming, use of humic substances plays important role, as it act as biostimulants to boost the yield of crop. Humic substances can be easily obtained by locally available organic sources. Hence, three different organic sources viz. Farm Yard Manure (FYM), vermicompost, lignite were characterized for their physico-chemical properties and quality parameters along with nutrients to judge their quality and maturity to extract humic substances. The potassium salt of humic acid extracted from these three sources were used as foliar application at different concentrations to study their effects on yield and quality of green chilli. Study Design: The pot culture experiment was conducted in Completely Randomized Design comprising eleven treatments with three replications. Place and Duration of the Study: The experiment was conducted in rabi season 2021-22 at College of Agriculture, Karad, Maharashtra, India. Methodology: Three organic sources viz. Farm Yard Manure (FYM), vermicompost and lignite were used to extract humic substances (humic and fulvic acid). These organic sources were studied for their physico-chemical properties and quality parameters along with their nutrient status to compare their quality and maturity for extraction of humic substances. Humic substances obtained from these different sources were studied for their content and characteristics. The potassium humate extracted from these organic sources were used in a pot culture study on green chilli, comprising eleven treatments and three replications. The different levels of potassium humate (200 to 600 ppm) were used as foliar application on transplanted chilli at 30 and 45 days after transplanting (DAT) along with recommended dose of fertilizers (GRDF) for studying its effects on yield and quality of green chilli. Results: Among all the three organic sources, vermicompost was reported as the best organic source to extract humic substances from its physico-chemical properties viz. pH (6.9), EC (0.3 dS m-1), water soluble organic carbon (0.76 %) and C:N ratio (18.0), which are considered as quality and maturity parameters to obtain good quality humic substances. Nutrient status for macro and micronutrients were reported to be higher in vermicompost followed by FYM and least content in lignite. In the pot culture experiment, the foliar application of potassium humate extracted from vermicompost resulted in significant improvement in fresh and dry yield of chilli fruit and stalk as compared to potassium humate application extracted from FYM and lignite. Among the various concentrations used (200-600 ppm) for the foliar application of potassium humate, application @ 400 ppm extracted from vermicompost along with GRDF (T7) was reported as the best treatment resulting in significantly increase in the fresh and dry yield of chilli fruits and stalk. Further, it was noticed that the same treatment was observed to be effective in significant improvement of the ascorbic acid content as quality parameter in fresh green chilli fruits.