Dry matter portioning, yield attributes and yield of Bt cotton as influenced by different fertigation levels with conventional and water soluble fertilizers

Abstract

A field experiment was undertaken to study the effect of different fertigation levels with conventional and water soluble fertilizers (WSF) on dry matter (DM) portioning, yield attributes and yield of Bt cotton at ARS, Dharwad, Karnataka during the kharif season of 2016-17. The results indicated that paired row (PR) sowing with fertigation of 100 per cent RDF (150:75:75 kg ha-1) through conventional fertilizers (CF) applied in six equal splits (T9) recorded significantly higher DM portioning to different parts and total DM production per plant at different growth stages as compared to other treatments. Regarding to yield and yield contributing parameters, PR sowing with fertigation of 100 per cent RDF through CF applied in six equal splits (T9) recorded significantly higher number of bolls plant-1 (54.40), seed cotton yield plant-1 (275.20 g) and seed cotton yield ha-1 (40 q ha-1) than other treatments, but was on par with PR sowing with fertigation of 30 per cent RDF (45: 22.5: 22.5 kg ha-1) through WSF and 25 per cent RDF through CF applied in six equal splits i.e T5 (50.07, 251.43 g and 38.94 q ha-1, respectively) and PR sowing with fertigation of 25 per cent RDF (37.5: 19: 19 kg ha-1) through WSF and 25 per cent RDF through CF applied in six equal splits i.e T6 (48.13, 243.27 g and 37.83 q ha-1, respectively). Significantly lower bolls plant-1 (39.20), seed cotton yield plant-1 (196.40 g) and seed cotton yield ha-1 (26.38 q ha-1) was recorded in PR sowing with fertigation of 15 per cent RDF (22.5: 11: 11 kg ha-1) through WSF applied in six equal splits (T4). Number of sympodia plant-1 and mean boll weight did not differ significantly among different treatments, but increased fertigation levels resulted increased number of sympodia plant-1 and mean boll weight.