Conservation agriculture in elephant foot yam (Amorphophallus paeniifolius) + banana (Musa AAB) system for higher productivity and profit: Results of an on-farm validation trial

Abstract

Field experiment was conducted in a farmer‘s field at Alathara, Kattela, Thiruvananthapuram, Kerala, during 2016-2017, to evaluate and identify varieties of elephant foot yam [Amorphophallus paeniifolius (Dennst. Nicolson)] adapted to conservation agriculture, to validate the resource conservation technologies for elephant foot yam in banana (Musa ABB) (var. Nendran) based system and to assess its impact on growth, yield, soil physico-chemical-biological properties, system productivity and profitability. Four varieties of elephant foot yam (Gajendra, Sree Padma, Sree Athira and Peerumade Local) were tested under two practices, viz. farmer’s practice (FP) and conservation agriculture (CA) practice, replicated thrice in split plot design, with varieties in main plots and practices in sub plots.The effect of varieties, practices and varieties × practices interaction was not significant for corm yield and bunch yield of banana. However, among the varieties, Sree Padma produced the highest fresh corm yield (1.9 kg/plant and 17.1 t/ha respectively). The bunch yield of banana (12.2 kg/plant and 30.5 t/ha respectively) was also highest under intercropping with elephant foot yam var. Sree Padma. Conservation agriculture out yielded farmer’s practice by 46.9% with respect to elephant foot yam yield and 4.2% for banana yield. Among the varieties × practices interaction, Sree Padma under conservation practice was the most productive (fresh corm yield and bunch yield of 23.1 t/ha and 31.7 t/ha respectively). The major, secondary and micronutrient status of the soil, except available Mn, physical properties of the soil, actinomycetes count, acid phosphatase and urease enzyme activities remained identical in the various treatments, indicating the equal efficiency of conservation agriculture to the existing farmer’s practice. Available Mn status was higher under conservation practice with Sree Padma var. The conservation treatment proved to be the most productive (by 11.1% over FP) and profitable (by 41.2% over FP) as revealed from the highest tuber equivalent yield (75.8 t/ ha), production efficiency (252.6 kg/ha/day), gross income (₹ 2273615/ha), net income (₹1743 454/ha) and B:C ratio (4.3). Among the treatment combinations, highest productivity (86.5t/ha) and profitability (net income of ₹ 2065307/ha; B:C ratio of 4.9), was realized from Sree Padma variety of elephant foot yam intercropped with Nendran banana under conservation agriculture.