Different nutrient application levels on okra's (Abelmoschus esculentus) growth and yield under drip fertigation was evaluated with a field experiment in comparison with flood irrigation. Results showed that drip fertigation improved the okra’s yield by 142% compared to surface flood (channel) irrigation and that this increase was statistically significant. An increase in nutrient applications above a recommended dose of fertilizers also significantly improved the yield by up to 100%. The HYDRUS model was calibrated and validated using the experimental data and various statistical parameters were used for comparing observed and predicted soil water content data. The volumetric soil water contents calculated using the HYDRUS model showed a good agreement with values measured at different horizontal and vertical distances from the drip emitter. The results also confirmed that soil water contents under drip irrigation were uniformly distributed within the root zone (i.e., 45 cm both vertically and horizontally from the plants). However, soil water contents were relatively low and showed larger variations within the plants' root zone under flood irrigation. Irrigation scheduling was simulated for the demonstration plots using the calibrated HYDRUS model for their respective soil conditions and validated with field observed soil water contents. An application of nutrients through drip fertigation improved crop yields in all demonstration plots, and an increase in yield over the control (flood irrigation) ranged from 13% to 317%. The benefit-cost ratio of drip fertigation for demonstration plots ranged from 2.05 to 3.50 for selected crops. Our study highlights that the adoption of drip fertigation with proper irrigation and nutrient scheduling (evaluated using HYDRUS) increases crop productivity and ensures higher efficiency of water, nutrients, soil fertility, environment sustainability, and profitable farming in Kerala.

通过田间试验与漫灌相比较，评估了滴灌条件下不同养分施用水平对秋葵 ( Abelmoschus esculentus ) 生长和产量的影响。结果表明，与地表漫灌（渠道）灌溉相比，滴灌使秋葵的产量提高了 142%，而且这种增加具有统计学意义。超过推荐剂量的营养素应用增加肥料还显着提高了产量，最高可达 100%。使用实验数据校准和验证 HYDRUS 模型，并使用各种统计参数来比较观测和预测的土壤含水量数据。使用 HYDRUS 模型计算的体积土壤含水量与在距滴灌器的不同水平和垂直距离处测量的值具有良好的一致性。结果还证实，滴灌下的土壤含水量均匀分布在根区（即距植物垂直和水平45厘米处）。然而，在漫灌条件下，土壤含水量相对较低，且在植物根部区域内表现出较大的变化。灌溉调度使用校准的 HYDRUS 模型针对各自的土壤条件对示范地块进行了模拟，并通过现场观察到的土壤含水量进行了验证。通过滴灌施肥提高了所有示范区的作物产量，与对照（洪水灌溉）相比，产量增加了 13% 至 317%。对于选定的作物，示范地块滴灌的效益成本比在 2.05 到 3.50 之间。我们的研究强调，采用滴灌施肥以及适当的灌溉和养分调度（使用 HYDRUS 评估）可以提高作物生产力，并确保喀拉拉邦的水、养分、土壤肥力、环境可持续性和盈利农业的效率更高。