Improving the productivity of okra (Abelmoschus esculentus L.) by strengthening the impact of applied nutrients through alligator weed compost

Abstract

Weeds produce huge biomass by competing with the main crop for resources has been well established by numerous investigators. The use of weeds, especially aquatic weeds, as an organic source of nutrients such as compost is lacking in the literature. We hypothesized that the use of aquatic weeds i.e. alligator as compost would limit the use of inorganic fertilizers in okra and it would increase the quality of produce. To maximize the effect of inorganic nutrients, it would be easier to use the alligator weed compost as a natural source of nutrients. The crop was sown on 22 July, 2017 and 20 July, 2018 in a randomized complete block design having four replications. The net plot size was 1.8 m x 6 m. The alligator weed compost along with NPK was applied at the time of sowing. Alligator weed compost was applied along with different combinations of NPK i.e. control (recommended dose of NPK 159-114-93 kg ha-1 ), compost application of 250 kg ha-1 , compost application of 500 kg ha-1 , compost application of 250 kg ha-1 with 75% recommended NPK, compost application of 250 kg ha-1 with 50% recommended NPK, compost application of 250 kg ha-1 with 25% recommended NPK, compost application of 500 kg ha-1 compost with 75% recommended NPK, compost application of 500 kg ha-1 with 50% recommended NPK and compost application of 500 kg ha-1 with 25% recommended NPK. Compost application of 250 kg ha-1 with 50% recommended NPK significantly reduced the number of days to flowering and increased plant height (cm) at flowering and plant maturity over the alone NPK and other combinations of compost and NPK. Pod yield and yield components were outclassed by the compost application of 250 kg ha-1 with 50% recommended NPK over the other combinations. For example, number of pods per plant and pod yield (t ha-1 ) were increased by 26%, 20%, respectively averaged across during both years of study over the recommended dose of NPK alone. Similarly, application of compost at 500 kg ha-1 along with NPK 50% of recommended dose enhanced pod potassium and ascorbic acid contents by 76% and 35%, respectively averaged across during both years of study over the control dose of NPK. Conclusively, alligator weed organic source of nutrients could reduce NPK fertilizers as it holds the nutrients applied and also provides the essential nutrients. In future climates, alligator weed compost would be a sustainable and environment friendly approach.