摘要
通过设置4.50×104、5.25×104、6.00×104、6.75×104、7.50×104株·hm^(-2)(分别用T1、T2、T3、T4、T5表示)5个密度,研究种植密度对玉米冠层结构、干物质积累及产量的影响,为川中丘区夏玉米高产栽培提供理论依据和技术支撑。结果表明:随种植密度增加,玉米叶面积指数显著增加,茎粗、茎叶夹角和透光率显著降低;密度每增加1×104株·hm^(-2),茎粗分别降低1.4 mm(2015年)和1.3 mm(2016年),穗下、穗上第1叶夹角分别降低3.601°、1.440°,吐丝期和灌浆中期底层透光率分别降低3.73%和2.82%;玉米单株干物质积累随种植密度增加显著降低,T5较T1在成熟期分别降低37.13%(2015年)、25.95%(2016年);而群体干物质随种植密度呈增加趋势,2016年T5较T1在吐丝后7天、成熟期分别增加了26.72%、23.41%;玉米产量随种植密度呈先增后降的变化趋势,在密度为6.00×104株·hm^(-2)下产量最高;该密度下玉米群体和个体功能达到协同增益,玉米产量构成(有效穗数、穗粒数和千粒重)协调,是产量提高的主要原因。
Five planting densities （4.50×104, 5.25×104, 6.00×104, 6.75×104 and 7.50×104 plants·hm-2, designated as T1, T2, T3, T4 and T5, respectively） were set up to explore the effects of planting density on canopy structure, dry matter accumulation and yield of summer maize, aiming to provide theoretical basis and technical support for highyield cultivation ofsummer maize in the hilly area of central Sichuan, China. The results showed that with the increase of planting density, leaf area index （LAI） of maize was significantly increased, whereas the stem diameter, the angle between stem and leaf, and the transmittance were significantlydecreased. With the planting density increasing by 1×104 plants·hm-2, the stem diameterdecreased by 1.4 mm in 2015 and 1.3 mm in 2016, the first leaf angles uppermost and underneath ear reduced by 3.601° and 1.440°, and the bottom transmission at silking and midfilling stages reduced by3.73% and 2.82%, respectively. The dry matter accumulation of individual maize was significantly decreased, while the dry matter increased with the increase of planting density. Compared with T1, the dry matter accumulation of per individual in T5 decreased by37.13% （2015）,25.95% （2016） at the maturity stage, and the dry matter accumulation at communitylevel of 2016 increased by 26.72%, 23.41% in 7 days after silking and at the maturity stage, respectively. With the increase of planting density, the yield of summer maize firstincreased and then decreased, with the highest value being found at 6.00×104 plants·hm-2. At such a density, the group and individual function of maize reached a synergistic gain and maize yield compositions （effective panicle number, grains per spike and grain weight） were coordinated, which accounted for the increase of maize yield.
出处
《生态学杂志》
CAS
CSCD
北大核心
2018年第3期891-897,共7页
Chinese Journal of Ecology
基金
国家重点研发计划项目(2016YFD0300307)
公益性行业(农业)科研专项经费(20150312705)
四川省玉米产业技术体系岗位专家项目资助
关键词
夏玉米
种植密度
冠层结构
干物质积累
产量
summer maize planting density canopy structure dry matter accumulation yield.
