Growth, development and profitability of rice (Oryza sativa L.) as affected by varying growing environments in north Western Himalayas

Abstract

A field experiment was carried out during kharif seasons of 2017 and 2018 to study the growth, development and profitability of rice varieties at different phenological stages under varying growing environments. The treatment had three cultivars viz., HPR 1068, HPR 2880 and HPR 2143 with five dates of transplanting viz., 15th June, 25th June, 5th July, 15th July and 25th July in Factorial RBD. The temperature variation among the selected transplanting window was about 1- 3 °C. The results of present study showed that the 15th June transplanted crop produced significantly taller plants and have higher tiller count throughout the crop cycle, though it was at par with 25th June transplanted crop, whereas, 25th July transplanted crop resulted in significantly shorter plants at all the stages of observation during both growing seasons. Similarly, a significantly higher value of leaf area index and dry matter was recorded in the 15th June transplanted crop which fall successively and significantly with delay in transplanting from the 15th June to 25th July transplanting at tillering to maturity, during both the growing seasons. The economics of crop shows that significantly maximum gross returns (103998 Rs ha-1 & 119877 Rs ha-1), net returns (73672 Rs ha-1 & 86001 Rs ha-1) and BC ratio (2.6 and 2.5) was recorded in crop transplanted on 15th June during both seasons whereas minimum gross returns (59317 Rs ha-1 and 68447 Rs ha-1), net returns (29081 Rs ha-1 and 34571 Rs ha-1) and BC ratio (1.2 and 1.1) was recorded in 25th July transplanted crop. The per cent decrease in net returns of 25th July transplanting over the 15th June transplanting was about 59-60%. Variety HPR 2143 recorded significantly taller plants, a higher number of tillers, Leaf area index, dry matter and returns followed by HPR 1068 and HPR 2880. The early transplanted crop took a relatively more number of days to attain phenological stages viz. tillering, panicle initiation, 50% flowering and maturity in all the three varieties viz. HPR 1068, HPR 2880 and HPR 2143 as compared to the late transplanted crop in both the years. Thus, the effect of transplanting dates in rice cultivation is considered to be of at most important for its higher productivity, sustainability and profitability.