Effects of application of nitrogen and potassium at different leaf age periods on yield and population quality of one-season-medium rice.
Wandao68 was used as material to study the effects of application of nitrogen and potassium in different leaf-age-periods on grain yield and population quality.The results are as follows:(1)The output of applying nitrogen at the third leaf age from top and potassium at forth leaf age from top was tiptop and the differences were significant.(2)Applying nitrogen at third leaf age from top could increase grains per panicle significantly while there was little effect on effective panicles per unit area,setting rate and 1000-grain weight;Applying potassium at forth leaf age from top could enhance grains per panicle and setting rate while there was little effect on effective panicle per unit area and 1000-grain weight.(3)Application of ear-fertilizer could control the inefficient tiller growing,increase the number of total spikelets,improve the effective leaf area percentage and high effective leaf area percentage,increase grain-leaf ratio,coordinate the relationship of ear and grain.It also could establish the plant type of resistance to lodging and improve the elevation of photosynthetic efficiency from heading to maturing to achieve high yield.