化控Ⅱ号对玉米群体冠层结构的影响

The Effect of CRCA II on Maize Population Canopy

通过层切法研究了在雌穗生长锥伸长期、雌穗小花分化期两个时期叶面喷施２００μｇ·ｇ－１、４００μｇ·ｇ－１、６００μｇ·ｇ－１三种浓度的化控Ｉ号对地膜玉米地上部群体结构的影响，认为雌穗生长锥伸长期叶面喷施４００μｇ·ｇ－１浓度的化控Ｉ号可增加玉米光合面积，增加叶重，提高粒叶比，增加果穗产量；雌穗小花分化期喷施效果不很明显。使用浓度过高，反而降低干物质转运率，造成果穗产量减少。

CRCA II(Chemical Regulate and Control Agent II) is a new kind of compound plant growth regulator(PGR).A Study was conducted to determine the effect of spraying CRCA II on maize(Zea mays L.) leaf at three degree concentrations of 200μg·g - 1,400μg·g - 1,600μg·g - 1.Field experiements were conducted to spray CRCA II at two ear bearing stages as ear growth comes to elongation stage(EGCES) and ear floscule differentiation stage(EFDS).The results show that the concentration of 400μg·g - 1 sprayed at EGCES can enlarge the leaf photosynthetic area,weight the leaf dry matter and increase the grainleaf ratio.There havn't obvious effects while spray CRCA II at EFDS.It also shows that excessively high concentration of CRCA II sprayed,lower photosynthate redistribution and grain yield were resulted.