Studies on performance of aerobic rice cultivars under different dates of sowing in Bihar

Abstract

A field experiment was conducted at Bihar Agricultural University, Sabour, (Bihar) during the kharif seasons of 2012-13 in upland situation to find out suitable high yielding aerobic rice cultivars under different sowing times. Aerobic rice is a new technique of growing rice characterized by direct seeding condition without standing water in the field. The experiment was laid out in split plot design with three replications having three date of sowing viz., 10 June, 20 June and 30 June in main plots and six cultivars of rice viz., Prabhat, Susk samrat, MTU1010, MTU1001, PHB71 and A6444 sown in sub-plots (Early, medium and hybrids cultivars). Recommended dose of fertilizers were 80:40:20 kg N:P:K ha-1. Herbicide Pendimethalin as pre-emergence @ 1.0 kg a.i. ha-1 was sprayed in saturated soil moisture as per the protocol of application time using knapsack sprayer fitted with flat fan nozzle at spray volume of 600 liters ha-1 just after sowing. Results of the experiment revealed that the sowing of aerobic rice on 20 June, significantly influenced most growth parameters, yield attributes, yield, nutrients uptake and economics was at par with 10 June sown aerobic rice, but it was significantly superior over later sowings (30 June). Delay in sowing resulted in reduction in grain yield, yield attributes and lower the economics. Amongst the aerobic rice cultivars PHB71 recorded significantly increased plant height (98.32 cm), leaf area index (3.86), crop growth rate(8.96 g m-2 day-1) dry matter accumulation (979.3 g m-2), effective tillers (316 m-2), grain per panicle t (83.87),test weight(23.96 g) and grains yield (6.58 t ha-1) followed by A6444. Lowest grain yield and yield attributes were recorded in 30 June with Prabhat rice cultivar during investigation.