新疆不同耐密型玉米品种光合性能及产量构成特征的研究

摘要

[Objective] Five density - tolerant maize cultivars were used to study the characteristics of photosynthesis and yield component under the drip irrigation so as to provide a theoretical support of maize high yield cultivation in Xinjiang. [Method]We studied the agronomic trait and photosynthetic performances including leaf area index, leaf area duration, net assimilation rate, and yield formation of dry matter accumulation as well as yield components of different density - tolerant maize varieties at 3 planting densities under the eco - climatic conditions of Xinjiang. [ Result ] The peak of leaf area index ( LAI) value of density -tolerant maize ZD909 was appropriate, and LAI got to peak earlier in the growth period and changed little both at before silking and after the grain - filling stage; the proportion of leaf area duration after anthesis, net assimilation rate and grain - leaf ratio as well as total and reproductive organs dry matter accumulation period were higher as a result of the higher yield at higher density. Although leaf area index, leaf area duration and dry matter accumulation volume were bigger in ZD808, the proportion of leaf area duration after anthesis, the net assimilation rate, and the grain - leaf ratio of ZD8O8 reduced significantly in higher density. Under conditions of 13.5×104 pl/hm2, the number of ears and the weight of grain lowered dramatically which limit the maize further increases in yield production. [ Conclusion] We can take full advantage of long time sunshine at the arid conditions in Xinjiang, and choose the better performance of canopy photosynthesis of density -tolerant varieties of maize by increasing planting density in order to tap the high yield potential of the varieties themselves to achieve high and stable yield ultimately in a large area.%[目的]研究滴灌条件下不同耐密型玉米品种光合性能及产量构成特征,为新疆玉米大面积高产栽培提供理论支持.[方法]在新疆气候生态条件下,选择5个不同耐密型玉米品种,在3个种植密度条件下探讨各处理群体冠层光合性能指标、干物质积累及其产量构成的特征.[结果]耐密型品种中单909叶面积指数(LAI)大小适宜,LAI到达峰值的时间较早,抽雄前与灌浆后LAI变化速率较小；花后光合势的比例、净同化率较高,粒叶比较大,总干物质和生殖器官干物质积累时间较长,高密度下收获株穗数和产量较高；稀植大穗型品种中单808虽然叶面积指数、光合势均较高、植株干物质积累量大,但花后光合势所占比例、净同化率和粒叶比均随密度增加显著降低.在高密度条件下(13.5×104株/hm2),群体收获穗数及穗粒重显著降低,严重制约了产量的进一步提高.[结论]在新疆干旱气候生态条件下,利用膜下滴灌技术,充分利用丰富的光照资源优势,选用冠层光合性能强的耐密型玉米品种,通过增加种植密度,挖掘品种自身的高产潜力,最终实现大面积丰产稳产.