川中丘陵雨养条件下春播和夏播玉米生长及产量差异研究

Differences of the Growth and Grain Yield Between Spring and Summer Maize under Rain-fed Conditions in the Middle of Sichuan Hilly Region

为明确川中丘陵春播和夏播玉米产量特性,以川中丘陵区大面积推广的10个玉米品种为材料,研究了春夏播对玉米生长、干物质积累和产量的影响。结果表明:川中丘陵区春夏播玉米在生育进程、植株形态、物质积累和产量上存在显著差异。与春玉米相比,夏玉米缩短了各生育阶段的持续时间,全生育期较春播平均缩短18.6 d。夏玉米株高、穗位高和穗位系数较春玉米分别提高了5.90%,28.36%,22.28%,吐丝期叶面积指数夏玉米也显著高于春玉米。拔节期干物质积累春玉米显著高于夏玉米,而成熟期则表现为夏玉米显著高于春玉米。玉米吐丝前物质积累率春播(40.74%)显著高于夏播(37.72%),而吐丝后物质积累率夏播显著高于春播。春播玉米收获指数平均为51.99%,较夏播收获指数提高了4.49个百分点,产量提高了7.09%。玉米品种间在植株形态、物质积累和产量上也存在显著差异,但春播和夏播间的表现不同。在川中丘陵区,春播玉米高产的关键在于提高叶面积指数,促进干物质积累,而夏玉米高产的关键是促进物质向籽粒分配,提高收获指数。

In order to clarify the yield characteristics of spring and summer maize in the Sichuan Hilly Region,a field experiment was carried out studying the differences of plant growth,dry matter accumulation and yield between spring and summer maize with 10 maize cultivars large area planted in the Sichuan Hilly Region. Results showed as follows: There was significant differences in the growing process,plant morphology,matter accumulation and yield between spring and summer maize. Compared with spring maize,the duration of each growth stages was shorten in summer maize,the whole growth period of summer maize was shorten 18. 6 days than spring maize. Compared with spring maize,the plant height,ear height and ear height coefficient of summer maize was increased by5. 90%,28. 36% and 22. 28% on average respectively. Meanwhile,the leaf area index of silking stage was also increased significantly in summer maize. The dry matter accumulation of spring maize was significantly higher than that of summer maize in jointing stage,while dry matter accumulation of summer maize was significantly higher than that of spring maize in maturity stage. The matter accumulation rate of previous silking in spring maize( 40. 74%)was significantly higher than that in summer maize( 37. 72%),while the matter accumulation rate of after silking in spring maize was significantly lower than that in summer maize. The average harvest index of spring maize was51. 99%,compared with Summer maize,it increased 4. 49 and the yield of spring maize was 7. 09% higher than summer maize. There were also significant differences among maize varieties in plant morphology,dry matter accu-mulation and the yield,and the differences of maize varieties was also different in spring maize and summer maize.In the Sichuan Hilly Region,increasing the leaf area index and improving dry matter accumulation was the key way of improving spring maize yield,while promoting the allocation to the grain and improving the harvest index was the key way of increasing the summer maize yield.