Effect of sowing date, row spacing and orientation on growth and yield of Bt cotton hybrid in southwest Punjab

To determine the effect of sowing date, row spacing and orientation on Bt cotton hybrid (RCH 773 BGII), the crop was sown on three dates i.e. April 30, May 15 and May 30 with two row orientations (North-South: N-S and East-west: E-W) and three row spacings (45 cm, 60 cm and 75 cm) in factorial split-plot design at Bathinda and Faridkot during Kharif2018. Plant spacing was kept same (67.5 cm) across all treatments. Phenological development of the crop was hastened with delayed sowing as compared to the 30^th April sowing under all treatments of row spacing and row orientation. The highest seed cotton yield was recorded when sown on April 30^th (3203 kg ha⁻¹ at Bathinda and 3370 kg ha⁻¹ at Faridkot) followed by May 15^th sowing; while the lowest with the crop sown on May 30^th. Signifcantly higher seed cotton yield was observed in E-W (3038 kg ha⁻¹ at Bathinda and 3085 kg ha⁻¹ at Faridkot) than in N-S row orientation. Seed yields were also higher with the wider row spacing of 75 cm (3004 kg ha⁻¹ at Bathinda and 3061 kg ha⁻¹ at Faridkot) as compared to the narrow row spacing. Ginning outturn (%) ranged from 32–33% and 37–38% at Bathinda and Faridkot, respectively. The study concluded that appropriate sowing date, row orientation and row spacing modifed the microclimate of cotton crop that had signifcant positive effect on growth and yield of cotton.