Weed dynamics and soil health in coconut plantations as affected by organic weed management practices

AbstractEco friendly weed management is crucial in sustaining soil health and crop productivity in coconut plantations. A study on the effect of organic practices on weed dynamics and soil health was undertaken in a 20-year-old coconut plantation with a spacing of 7.5 m × 7.5 m. The organic weed management practices tested included: live mulching with dhaincha (Sesbania aculeata) or horsegram (Macrotyloma uniflorum) or cowpea (Vigna unguiculata) in the interspaces of coconut trees, intercropping with turmeric (Curcuma longa), mulching interspaces of coconut trees using phyto-pharmaceutical waste (byproduct of the ayurveda industry) 20 t/ha, ploughing the interspaces of coconut trees (twice per year). Unploughed interspaces of coconut trees without weeding operations served as check. Weed density and biomass were monitored. Soil samples were periodically analysed for nutrient status and microbial population changes. Grasses were the dominant weeds, followed by broad-leaved weeds. Live mulching and mulching with phyto-pharmaceutical waste resulted in more than 90 % weed control. Mulching with phyto-pharmaceutical waste was free of weeds even after one year of application. Enhanced microbial biomass carbon, dehydrogenase activity, as well as acid phosphatase activity, were observed in plots where intercropping practices or organic waste mulching was practiced. Organic weed management practices not only provided effective weed management but also enhanced soil fertility and microbial activity, making them ideal option for eco-friendly weed management in coconut plantations.