Abstract

Bt cotton is the major cash crop of Gujarat. Scarcity of groundwater, high evaporative conditions and deficient rainfall condition compelled farmers to adopt drip irrigation with mulch. Lack of knowledge on combined impact of drip irrigation regimes and mulch on water saving and its economy constrained mass adoptability of this technique. Keeping this in view, an experiment was conducted at Junagadh for two consecutive years (2012–13 and 2013–14) to assess the combined impact of irrigation regimes (0.6, 0.8 and 1.0 ETc), mulch material (silver black plastic mulch, biodegradable plastic mulch and wheat straw mulch), and irrigation systems (drip and furrow) on yield of Bt cotton Hybrid 6. Split plot design with three treatment replications was adopted. Drip irrigation with silver black plastic mulch scheduled at 0.8 ETc yielded high morphological variables, yield attributes and WUE than other treatments accounted in the study. Drip without mulch outperformed than furrow irrigation system (4.82 kg/ha/mm). Seed cotton yield of drip with silver black plastic mulch was 2.1 folds over furrow method, 1.40 folds over drip irrigated cotton, 1.15 folds over biodegradable plastic mulch and 1.31 folds over wheat straw mulch at 0.8 ETc. The drip irrigation technique coupled with silver black plastic mulch improved the crop productivity. Highest benefit: cost ratio was 2.64 for silver black plastic mulch at 0.8 ETc. B: C ratio for wheat straw and drip irrigation without mulch were at par and furrowly (B: C ratio 1.60) grown cotton.