Influence of Weed Management Practices on Soil Microbial Activities and Corm Yield of Elephant Foot Yam (Amorphophallus paeoniifolius) in Alfisols of Coastal Odisha

Abstract

Field experiments were carried out to study the effect of various weed management practices on soil quality, microbial activities, and yield performance of elephant foot yam [Amorphophallus paeoniifolius (Dennst.) Nicolson] in an Alfisol of coastal Odisha during kharif, 2015-16 at the Regional Centre of ICAR Central Tuber Crops Research Institute, Bhubaneswar, Odisha, India. The results of the study revealed that weed control ground cover has recorded lower weed biomass and greater weed control efficiency. Significantly highest corm yield of elephant foot yam was registered with weed control ground cover (37.4 t ha^-1) with an increase of 335% over control followed by four manual weedings at 30, 60, 90 and 120 days after planting (DAP) (33.7 t ha^-1) and two manual weedings at 30 and 60 DAP along with the post-emergence application of glyphosate at 90 DAP (32.9 t ha^-1). Maximum gross returns were observed in weed control ground cover, however, the highest benefit-cost ratio was noticed due to two manual weedings at 30 and 60 DAP + spraying of glyphosate at 90 DAP. Use of weed control ground cover resulted in greater soil available N, P, K, Fe, Cu, Mn and Zn as well as microbial (fungi, bacteria and actinomycetes) counts and soil enzyme (dehydrogenase, fluorescein diacetate, acid and alkaline phosphatase) activities. The study emphasized that weed control ground cover, manual weeding at periodic intervals or manual weeding combined with the application of post-emergence herbicides not only enhanced the corm yield but also improved the soil quality parameters and microbial activities in the soil.