Effect of varied levels of Salvinia molesta vermicompost on soil fertility and crop productivity of rice under coastal conditions of Udupi, Karnataka

It was found that using Salvinia molesta vermicompost at a rate of 13.2 t/ha or Salvinia vermicompost with an additional 45:13:62 kg N:P:K/ha resulted in significantly improved growth parameters such as plant height (89.94 cm), number of tillers/m2 (520.24), and total dry matter production (77.52 g/plant) at harvest. Additionally, yield parameters like productive tillers/m2 (499.95), panicle length (21.86 cm), grain yield (5.23 t/ha), straw yield (6.66 t/ha), harvest index (0.44), and low chaff percentage were also positively impacted. The next best treatment was the application of 9.9 t/ha of Salvinia vermicompost along with 45:13:62 kg N:P:K/ha. Furthermore, significantly higher levels of available N (389.65 kg/ha) and K (225.42 kg/ha) in the soil were observed with the Salvinia vermicompost application. However, the application of 3.3 t/ha of Salvinia vermicompost with 45:13:62 kg N:P:K/ha resulted in the highest benefit-cost ratio of 2.50.