【摘要】 研究了西宁地区地膜覆盖、露地栽培和不同播种时期玉米叶片生长的规律。结果表明 ,玉米叶面积及其增长速度在主茎上均呈现出随着叶位上升而持续增加 ,以后又逐渐缩小的规律。最大叶位叶龄指数为 81 1 % ,变异系数CV =7 4%。当叶龄指数为 81 %～ 90 %时 ,叶面积增长速度最快。覆膜和早播可使玉米早出苗、叶片数增加、叶面积增大 ,覆膜还使出叶及叶面积增长速度明显加快更多还原

【Abstract】 The laws of leaf growth of corn under the condition of plastic ground covers,open ground and several different sowing dates are studied.The result showed that the area and growing speed of leaf on stem show this low that it gradually increase during early period as the leaf position rising and then decrease.The leaf age index of the seat of the maximum leaf is 81.1%,CV=7.4%.The growing speed of the leaf is most fast when the leaf age index is 81%～90%.The plastic ground covers and the earlier sowing can make emergence of seedlings earlier and increase the leaf number and area.Plastic ground covers also can quicken the speed of the leaf and the leaf growth obviosly.更多还原