播种方式和施氮量对滴灌冬小麦群个体生长特征的影响

Effects of Sowing Methods and Nitrogen Application Rate on Individual Growth Characteristics of Winter Wheat under Drip Irrigation

长期以来新疆麦区形成了以条播种植为主的"高密度、小株型"栽培模式。随着滴灌技术的应用,条播造成的群体分布不均匀加剧了群个体发展以及营养生长与生殖生长之间的矛盾,制约了小麦高产潜力的更好发挥。以邯郸5316为试验材料,采用裂区田间试验设计方法,主区为条播(B_(1))、穴播(B_(2))和撒播(B_(3))3种播种方式,副区为施氮量0(N_(0),不施氮)、138(N_(1))、207(N_(2))和276 kg/hm^(2)(N_(3))4个水平,研究了不同播种方式和施氮量对滴灌冬小麦株高以及群体总茎数、叶面积指数、冠层叶倾角和产量的影响。结果表明:播种方式对滴灌冬小麦群个体生长特征和产量均有重要影响,其中穴播效果最好,该播种方式下小麦中后期株高增速最快,群体总茎数在生育前期增长较平稳、春季拔节期达到最高后减少幅度较小,成熟期收获穗数最多、成穗率最大,群体LAI在孕穗期最高(达7.21)且后期下降较慢,小麦冠层平均叶倾角最小,产量最高且显著高于条播和撒播(分别较B1和B3处理平均增产10.66%和11.31%);随着施氮量的增加,小麦株高、群体总茎数、群体LAI和产量均呈先增加后降低的变化,冠层平均叶倾角呈先减小后增大的变化,其中N2处理效果最好,该施氮量下小麦平均株高、群体LAI、成穗数和成穗率最大,冠层平均叶倾角最小,平均产量最高。试验组合中,B_(2)N_(2)组合(穴播,施氮量207 kg/hm^(2))产量最高,群体质量最优,该处理下小麦株高83.94 cm,冬前总茎数1479.81万株/hm^(2),拔节期最高总茎数1847.18万株/hm^(2),成熟期收获穗数721.35万穗/hm^(2),成穗率39.05%,拔节期、孕穗期、灌浆期的群体LAI分别为3.66、7.99和4.32,产量达到9144.75 kg/hm^(2)且明显高于其他组合处理。研究结果可为生产上小麦群体指标调控提供借鉴。

For a long time,the cultivation mode of high density and small plant type based on drill planting has been formed in Xinjiang wheat region.With the application of drip irrigation technology,the uneven population distribution caused by drilling increased the contradiction between individual development and vegetative growth and reproductive growth,which restricted the better development of high yield potential of wheat.Taking Handan 5316 as the material,the split plot field experiment design was used,the main area was divided into three sowing methods:drilling(B1),hole sowing(B2)and sowing(B3),and the sub-area was treated with four nitrogen application rates:no nitrogen(N0),138 kg/hm^(2)(N_(1)),207 kg/hm^(2)(N_(2))and 276 kg/hm^(2)(N_(3)).The effects of different sowing methods and nitrogen application rates on the plant height,total stem number,leaf area index,canopy leaf inclination and yield of winter wheat under drip irrigation were studied.The results showed that the sowing methods had an important influence on the individual growth characteristics and yield of winter wheat under drip irrigation,and the effect of hole sowing was the best.The growth rate of plant height was the fastest in the middle and late stage of wheat under this sowing mode.The growth of total stem number of population was relatively stable in the early growth stage,and the decrease range was small when it reached the highest at jointing stage in spring.The ears number was the largest and the ear rate was the largest in mature stage.The population LAI was the highest at booting stage(7.21)and decreased slowly at later stage.The average canopy leaf inclination angle was the smallest,and the yield was the highest,which was significantly higher than that of sowing and sowing(increased by 10.66%and 11.31%compared with B1 and B3,respectively).With the increasig of nitrogen application rate,the plant height,population total stem number,population LAI and yield of wheat increased at first and then decreased,and the average canopy leaf inclination decreased at first and then increased.The effect of N_(2) treatment was the best.Under this nitrogen application rate,the average plant height,population LAI,ears number and ear rate were the largest,the average canopy leaf inclination was the smallest,and the average yield was the highest.The population quality of B_(2)N_(2) was the best,the plant height was 83.94 cm,the total number of stems before winter was 14.7981 million plants/hm^(2),the highest total number of stems at jointing stage was 18.4718 million plants/hm^(2),the number of ears harvested at maturity stage was 7.2135 million ears/hm^(2),and the ear forming rate was 39.05%.The population LAI at jointing stage,booting stage and filling stage were 3.66,7.99 and 4.32,respectively,and the yield reached 9144.75 kg/hm^(2),which was significantly higher than that of other combinations.The results can provide reference for the regulation of wheat population index in production.