干旱条件下籽粒大小与播种深度对夏玉米幼苗生长及产量的影响

为探究籽粒大小与播种深度对玉米出苗及幼苗生长的影响,确定西南丘陵地区夏玉米机播的适宜籽粒大小与播种深度。采用裂区试验设计,以正红505为试验材料,3个籽粒大小为主处理,3个播种深度(2,6,10 cm)为副处理,在大田干旱条件下调查了玉米的出苗率、幼苗素质、产量及产量构成。结果表明,大粒种比小粒种出苗率高,出苗后长势旺,干物质积累量增加,幼苗健壮,抗旱性增强,最终产量更高;浅播(2 cm)利于出苗,刚出苗时以6 cm播深的幼苗长势最好,之后10 cm播深的幼苗生长逐渐旺盛,至五叶期(大、中粒种)-七叶期(小粒种)时超过浅播处理,最终也表现出一定的增产效果。因此,在旱地、旱季玉米生产中,选较大粒播种,适当深播,可以有效地培育壮苗、提高植株抗旱性,达到保产增收的目的。

Effect of Grain Size and Sowing Depth on Seedling Growth and Yield of Summer Maize in Drought Condition

In order to explore the effect of grain size and sowing depth on emergence and seedling growth,de-termining suitable grain size and sowing depth in mechanization of summer maize production of Southwest Hilly Are-a.In the split-plot design,using Zhenghong 505 as the test material,3 kinds of grain size was assigned to the main plot,and 3 sowing depth (2,6,1 0 cm)to the subplot,emergence rate of maize,seedling quality,yield and yield components have been investigated in drought condition.The results showed that compared with small grain,large grain had higher emergence rate,the seedling was more haleness and grew better in drought,and there was a certain effect of increasing yield ultimately;Shallow sowing(2 cm)was conducive to the emergence,and the growth vigor of the seedlings of 6 cm sowing depth was best just when emerging,then the 1 0 cm depth of the seedling grew gradual-ly strong,and obviously better at the 5 leaf period(large and medium grain)-7 leaf period(small grain)than shal-low sowing treatment,which also showed a certain increase in yield.Therefore,in the dry land or dry season,choo-sing large grain and suitable sowing depth in maize production can effectively better sthong seedlings,improve the resistance of drought,and achieve the purpose of producing income insurance.