瘠薄亚表层施磷对大豆生长及产量的影响

为促进大豆磷高效利用,通过盆栽模拟试验,在贫磷的亚表层土壤里施过磷酸钙,研究不同磷用量0 kg·hm~(-2)(T_0)、30 kg·hm~(-2)(T_1)、60 kg·hm~(-2)(T_2)、120 kg·hm~(-2)(T_3)、240 kg·hm~(-2)(T_4)对大豆黑农48的生育性状及产量的影响。结果表明:大豆苗期对磷的反应较弱,施磷处理与对照相比对株高、干物质质量的影响差异不显著,SPAD值表现为T_3T_2T_4T_1T_0,其中T_3与T_0处理差异显著,其它各处理间差异未显著;大豆结荚期(R4)表现为:随着施磷量的增加,根系指标及干物质质量呈单峰曲线变化,施磷促进大豆根长、根表面积增大,根瘤数的增加,利于干物质的积累,施磷量≥120 kg·hm~(-2)的处理与≤30 kg·hm~(-2)的处理差异达显著;大豆产量施磷处理与不施磷处理间差异显著,但年季间略有差异,2016年最佳施磷处理为T_2,T_3比T_0处理增产10.5%~12.1%,2017年最佳施磷为T_3处理,盆栽产量为73.0 g,且表现为T_3T_2T_4T_1T_0的趋势,T_3处理与其它各处理差异显著。两年的试验结果进一步证明,在瘠薄缺磷的土壤上进行亚表层磷培肥,最佳施磷处理为T_3,即120 kg·hm~(-2)时为最佳施肥量,能够促进大豆根系的生长,对大豆高产具有重要的意义。

Effect of Barren Subsurface Application of Phosphorus on Soybean Growth and Yield

In order to efficiently utilize phosphorus in soybean field,pot experiment was used to simulate the application of SSP on the phosphorus-depleted subsurface soils to study the effects of different amount of phosphorus (0 kg· ha-1 (T0),30 kg· ha-1 (T1),60 kg· ha-1 (T2),120 kg· ha-1 (T3),240 kg· ha-1 (T4)) on the growth and yield of soybean Heinong 48.The results showed that:Soybean had weak response to phosphorus at the seedling stage,the difference of plant height and dry matter weight was not significant when the phosphorus was applied compared with the control,the SPAD value showed the trend of T3 ＞T2 ＞T4 ＞T1 ＞T0,T3 treatment with 120 kg·ha-1 had significant difference compared with T0.During the podding stage of soybean (R4),the effects on the nodule,root index and dry matter weight of soybean were single peak curve or straight line trend with the increase of phosphorus application.Phosphorus promoted the root growth,root length,root surface area and root nodule increased,which was conducive to the accumulation of dry matter.The difference of the treatment of phosphorus higher than 120 kg·ha-1 and less than 30 kg·ha-1 was significant.Phosphorus application on soybean yield compared with no phosphorus treatment showed significant difference,but there were slight differences between years,the best phosphorus application in 2016 was the treatments of T2 and T3,the yield was increased from 10.5％ to 12.1％ than T0 treatment.In 2017,the best phosphorus application was T3 treatment,the pot yield was 73.0 g,which showed the trend of T3 ＞ T2 ＞ T4 ＞ T1 ＞ T0,T3 treatment was significantly different from other treatments.Two years of test results further proved that in the poor phosphorusdeficient soil sub-surface,the best phosphorus application amount was T3 treatment(120 kg· ha-1),which could promote the growth of soybean root system,which was of great significance for high yield of soybean.