Organic management fosters yield, soil health and profit in dwarf white yam

Organic farming is a safe alternative for sustainable production, clean food, soil and air. Field experiments were conducted in randomized block design over three consecutive seasons (2011–2014) in non-trailing genotype of white yam to compare the yield, quality and soil properties under conventional, traditional, organic and integrated system at ICAR-Central Tuber Crops Research Institute, Kerala. This was followed by on-farm trials for one year (2014–2015) at seven locations in two major yam growing districts of Kerala, to validate the on station developed technology. At on-station, organic system (13.23 t/ha) performed better than chemical (12.18t/ha) with 8.6% higher yield and insignificant effects on tuber quality. Organic plots showed higher pH (+0.412 unit), organic C (+22%), available N (+44%) and K (+7%), exchangeable Ca (+16%), Fe and Cu (+8%). The soil temperature, soil moisture, soil CO₂ flux and photosynthetically active radiation were also slightly promoted under organic management. The population of bacteria, fungi and actinomycetes were higher under organic (+12.87%, +58.69% and +48.85% respectively). Subsequently, the on-station developed organic technology comprising farmyard manure, green manure, neem cake, biofertilizers and ash tested on-farm confirmed that the yield and profit under organic management were higher by 21 and 38% respectively over conventional system. These results are valuable for the promotion of organic farming in non-trailing genotype of white yam for higher yield, profit and soil health.