Effects of nitrogen application amount and planting density on yield and growth characteristics of hybrid keng rice cultivar Changyou 1.

The three-way hybrid keng rice Changyou 1 was used as a test material,and the effects of nitrogen application amount and planting density on the rice yield and growth characteristics were studied.The results showed that the effects varied with nitrogen application amount and planting density. The nitrogen application amount of 270 kg/hm~2 and planting density of 500 000 seedlings/hm~2 could gain the highest yield.The effects of both nitrogen application amount and planting density were very significant on the number of effective panicles and grains per spike,significant on the 1 000-grain weight,and not significant on the seed setting rate.The effects of both nitrogen application amount and planting density on the growth characteristics of rice population such as tiller number,LAI,and production and accumulation of dry matter were basically the same as those on the rice yield in change trend.It was preliminarily concluded that the appropriate nitrogen application amount and planting density for high yield culture of the cultivar Changyou 1 transplanted by machine were respectively 210～330 kg/hm~2 and 500 000 seedlings/hm~2,and the best nitrogen application amount was not more than 270 kg/hm~2.