不同类型饲用玉米群体光合生理特性的研究

对两种类型饲用玉米的群体生理特性进行了研究，结果表明：青贮型玉米的叶面积和叶面积系数较大，吐丝前叶面积增长快，吐丝后叶片衰老略快，拔节至吐丝25d期间作物生长率较高，光合势和干物质积累量大，是决定生物学产量的关键时期，青贮型玉米科多8号的适宜密度在67500株／hm^2左右；粮饲兼用型玉米叶面积和叶面积系数较小，吐丝前叶面积增长较快，吐丝后叶片衰亡较慢，吐丝后至成熟期期间干物质积累量和光合势大，作物生长率高，是决定其生物学产量和籽粒产量的关键时期，粮饲兼用型玉米陕单310的耐密性较好。

Photosynthetic and Physiological Characteristics of the Populations of Different Types of Silage Maize

The study of photosynthetic and physiological characteristics of the populations of two types of silage maize was conducted and the results were as follows:of silage maize,the leaf area and leaf area coefficient were bigger.While the leaf area increased quickly before silking,leaf doated quickly after that.During the period from jointing to 25 days after silking,not only the plant growth rate was higher,but also the photosynthesis potential and amounts of dry matter accumulation were big,which was the key stage for determining biological yield.The suitable density of KD8,the silage variety,was about 67 500 plants/hm~2.As to maize of foodstuff and silage type,its leaf area and leaf area coefficient were smaller.While the leaf area increased quickly before silking,the leaf doated slowly after that.During the period from silking to ripeness,not only the plant growth rate was high,but also the photosynthesis potential and amounts of dry matter accumulation were big,which was the key stage for determining biological and grain yield.Shaandan 310,the variety of foodstuff and silage type,had a good dense characteristic.