种植密度对不同株型夏玉米产量和冠层特性的影响

Planting Densities Affect the Yield and Canopy Characteristics of Different Summer Maize Plant Types

为了指导不同株型夏玉米品种的田间生产,选用平展型品种‘鲁单981’和紧凑型品种‘鲁单818’为供试材料,通过设置30000株/hm^2(D1)、60000株/hm^2(D2)、90000株/hm^2(D3)3个种植密度,研究了密度对不同株型夏玉米产量、叶面积持续期(LAD)、叶面积指数(LAI)、群体净同化率(NAR)的影响。结果表明,‘鲁单981’在D2时产量最高,为11452 kg/hm^2,‘鲁单818’在D3时最高,为13024 kg/hm^2。在D3下,紧凑型品种‘鲁单818’的LAD[452(m^2·d)/m^2]及花后比例(50%)、穗位叶LAI以及全生育期NAR[6.87 g/(m^2·d)]更高。上述研究结果表明紧凑型品种冠层结构紧凑,中下层受光充足,LAD延长,有利于干物质积累,产量上升,更适合高密度栽培。

The aim is to guide the field production of different summer maize plant types.The horizontal variety’Ludan981’and compact variety’Ludan818’were selected as the test materials,three different planting densities(D1,30000 plant/hm^2;D2,60000 plant/hm^2;D3,90000 plant/hm^2)were set up,the effects of planting densities on the yield,leaf area duration(LAD),leaf area index(LAI),and net assimilation rate(NAR)of different summer maize plant types were studied.The results showed that the yield of’Ludan981’and’Ludan818’was the highest at D2(11452 kg/hm^2)and D3(13024 kg/hm^2),respectively.Under D3,compact variety’Ludan818’had a higher LAD[452(m^2·d)/m^2]and proportion after flowering(50%),ear LAI and NAR during whole growth period[6.87 g/(m^2·d)].The above results indicate that compact variety has a more compact canopy,leaves in the middle and lower layers intercept more light,which could extend the LAD and contribute to the dry matter accumulation and yield increase.Thus,the variety is more suitable for high density cultivation.