不同基因型玉米品种源库调节对籽粒产量形成的影响

在45000和75000株/hm2两个密度下,于吐丝期分别对大穗型玉米品种陕单902和小穗型玉米品种户单4号进行了剪50%叶、剪50%穗、断50%根等减源、减库处理,研究不同类型玉米品种库源调节与籽粒产量形成的关系。结果表明,减源处理对籽粒产量的影响大小为叶>根;源库变化对籽粒产量影响大穗型品种为源>库,小穗型品种为库>源;在源库同时减少50%时,两品种籽粒产量下降约50%。源不变,库容减少,源库比增加时玉米茎杆可溶性糖和物质残留率增加,干物质积累量和籽粒产量下降20%～30%;库容不变,源减少,源库比降低时玉米茎杆可溶性糖和物质产留率降低,干物质积累量和籽粒产量同样下降20%～30%。始终维持源库在群体上的相对平衡是玉米高产栽培中的主要措施。

Effect of source-sink adjustment on yield of grain formation of different genotype maizes

During spinning period,big-ear maize Shaandan 902 and small-ear maize Hudan 4 are respectively cut fifty percent of leaves,roots and spikes under 45000 and 75 000 plant/hm~2.The results showed:Effected degree of treatments of reducing source on grain yields is that leaves are bigger than roots;Effected degree of changes of source and sink on grain yields is that,as to big-ear maize,source is bigger than sink and that,as to small-ear maize,sink is bigger than source;When source and sink were simultaneously cut 50%,grain yields of two types of maize decreased about 50%.When source kept unchanged,capacity of sink decreased and rates of source-sink increased,soluble sugar and rudimental rates of matter in stem increased,but accumulated quantity of dry matter and grain yield decreased 20%-30%;When capacity of sink kept unchanged,source decreased and rates of source-sink decreased,soluble sugar and rudimental rates of matter in stem decreased,and accumulated quantity of dry matter and grain yield decreased 20%-30%.It is obvious that keeping a relative balance between source and sink is an important measure in high-yield growth of maize.