A novel technique to apply irrigation water at sub-surface from existing surface drip irrigation system in grapevine: Effect on yield, nutrient content and water use efficiency

Improving water use efficiency is the key to sustaining grape production especially in hot and dry tracts of Maharashtra. For this, a novel technique using hollow PVC pipes to directly apply irrigation water at sub-surface (22.5 cm depth) in the root zone from the already laid down surface drip irrigation system was compared with surface drip irrigation method for three consecutive cropping and six pruning seasons. Application of irrigation water using sub-surface irrigation technique produced significantly higher yield, brix yield (TSS x yield/100), bunch weight, pruned biomass and nutrient content compared to corresponding surface drip irrigation level at 50 and 75% levels of recommended irrigation level. New sub-surface irrigation technique at 75% irrigation level produced yield and brix yield equivalent to 100% surface drip irrigation level, thereby leading to significantly higher water use efficiency. The average benefit-cost ratio was higher for new sub-surface irrigation technique at 75% recommended irrigation level (1.74) compared to surface drip irrigation at 100% recommended irrigation level (1.67). To further economise on the cost of the implementation of this novel sub-surface irrigation technique during 2005–2006, waste plastic bottles used for mineral water were used instead of PVC pipe at 50% irrigation level with similar results.