机插密度对杂交稻干物质积累及产量形成的影响

Effects of transplanting density on dry matter accumulation and yield formation of machine transplanted hybrid rice

为明确适宜的杂交稻机插株距及种植密度,选取中浙优8号及甬优12为材料,设置14、16、18和21cm4个机插株距,研究不同种植密度对杂交稻生长及产量的影响。结果表明：随着机插株距的增大,2个水稻品种植株个体虽然均生长健壮,单株茎蘖数增加,但群体总茎蘖数下降,且后期茎蘖消减较快,最终茎蘖成穗率出现一定的下降趋势;同时,机插株距的增大引起植株群体干物质积累量减小,其干物质主要转运至茎叶部位,穗部干物质积累比例未有明显提高。从最终产量表现来看,机插株距的增大导致田间有效穗数显著降低,产量也随之减少。综上可以看出2个水稻品种均需要一定的种植密度才能保证高产,最适株距应调节至14~18cm,种植密度保持在18.5~23.8穴/m2。

To explore suitable transplanting spacing and density of hybrid rice under mechanically transplanting condition,Zhongzheyou 8and Yongyou 12 were adopted as test materials to study on the effect of different planting densities on the growth and yield of hybrid rice.Different planting densities of four transplanting spacing（14,16,18and21cm）were designed.The results showed that：With the increase of transplanting spacing,individual plant of both varities were vigorous,the tillers of single plant were increased.However,the total number of tillers was decreased significantly,and the spike rate displayed a trend of reduction.With the increasing of transplanting spacing,the dry matter accumulation of plants was decreased since the dry matter was mostly transported to stems and leaves,and had small contribution to grain yield.From the performance of rice productivity,increasing transplanting spacing could reduce the effective panicle significantly and caused reduction of grain yield.Therefore,high yield hybrid rice need certain degree of planting density,the suitable density was 18.5to 23.8points each m2,and the suitable spacing was between14 to 18cm.