Evaluating In-situ moisture-conservation measures with soil conditioner (PUSA hydrogel) on soil moisture fluctuations and productivity of cotton (Gossypium hirstum) under rainfed Vertisols

A field experiment was conducted at Aruppukottai, Tamil Nadu during rabi season of 2016-17 and 2017-18 to study the impact of in-situ moisture-conservation and stress-management practices on soil-moisture retention and productivity of ‘SVPR 2’ cotton (Gossypium hirsutum L.) under rainfed Vertisols. The experiment was laid out in a split-plot design, replicated thrice. The main-plot treatments, consisted of different in-situ moisture-conservation measures viz. broad bed and furrows (I₁), ridges and furrows (I₂) and compartmental bunding (I₃). The sub-plot comprised with stress-management practices, viz. soil application of PUSA hydrogel @ 5 kg/ha (S₁), soil application of PUSA hydrogel @ 5 kg/ha + foliar spray of 1% KCl (S₂), soil application of PUSA hydrogel @ 5 kg /ha + foliar spray of 5% Kaolin (S₃), soil application of PUSA hydrogel @ 5 kg/ha + foliar spray of PPFM @ 500 ml/ha(S₄), soil application of PUSA hydrogel @ 5 kg/ha + foliar spray of salicylic acid 100 ppm (S₅) and the control (S₆). Data analysis of 30 years rainfall was done for the probability occurrence of dry spell in particular standard weeks by the Markov chain method. The results of this study showed that treatment combination of broad bed and furrows and soil application of PUSA hydrogel @ 5 kg/ha + foliar spray of PPFM @ 500 ml/ha resulted in significantly higher soil-moisture content at various depth of 0-15, 15-30 and 30-45 cm and seed-cotton yield 1,580 kg/ha (2016) and 1,943 kg/ha (2017).