Response of SPAD and Yield to Planting Density and Fertilizer Application for Winter Wheat

Pubing 9946,was used to study the effects on SPAD and grain yield with five fertilizer levels and four planting densities.The result showed that under treatments with different planting density and fertilization,SPAD at standing stage and at flowering stage were different,and SPAD at jointing stage and at filling stage were significant different.In the treatment combinations of density 315× 10 4 hm-2 + N 225kg / hm 2 + P 150kg / hm 2 + K 150kg / hm 2 and density 315×10 4 hm-2 + N 300 kg / hm 2 +P 200kg / hm 2 + K 200kg / hm 2,the winter wheat could have high SPAD among different growth stages.In the treatment of density 315×10 4 hm-2 +N 225kg / hm 2 +P 150kg / hm 2 +K 150 kg / hm 2,the winter wheat could have the highest spikelet number(44.92grains per panicle) and yield(9 873.00kg / hm 2),which also had higher thousand kernel mass and the number of ear bearing tiller.There were significant positive correlations between SPAD and effective panicle,kernels per spike and yield but inverse correlation between SPAD and thousand kernel mass.The effect of SPAD of wheat on effective panicle,kernels per spike and yield had begun since jointing stage,especially at jointing stage and flowering stage.Therefore,with a suitable increase of fertilization quantity and planting density,the winter wheat could have a relatively steady and high SPAD during the whole life,and the spikelet number and yield also increased significantly.