不同播期对油菜产量及根系电容值的影响

Effects of Different Sowing Dates on Grain Yield and Root Capacitance of Rape

由于在油菜播种期间受到前茬作物或极端天气等原因的影响,推迟播种是油菜生产中经常面临的栽培调控手段。为探讨推迟播种对油菜产量及根系形态的影响,以甘蓝型油菜品种‘甘杂1号’与‘秦优33’为材料,设定3个播期,分别为9月25(正常播期)、10月5日、10月15日。结果表明,与正常播期相比,晚播显著降低油菜产量(-21.3%)、根长(-56.8%)、根表面积(-47.3%)、根体积(-44.2%),根干质量(-41.2%)与地上部干物质量(-13.6%)也随之下降。根系电容(EC)与根系形态(R2=0.459~0.809**)和产量(R2=0.808**)存在显著正相关关系,而根系电阻抗(EI)与根系形态(R2=0.289~0.523**)和产量(R2=0.647**)存在显著负相关关系。说明,根长、根表面积、根体积、干物质积累量及产量受播期影响显著,选择适宜的播期是保证高产的前提。此外,EC/EI作为一种快速且无损的根系原位检测技术,可以用来预估不同播种时间导致的根系形态与产量的变化。

Delayed sowing is a common measure for regulating cultivation in rape production because of the sowing dates were affected by previous crops and extreme weather during sowing period.In order to determine the effect of delayed sowing on the grain yield and root morphologies of rape,two Brassica napus varieties(‘Ganza 1’and‘Qinyou 33’)were used as materials,three sowing dates including September 25(normal sowing date),October 5 and October 15(delayed sowing dates)were set.Compared with normal sowing date,the delayed sowing treatment significantly decreased the grain yield,root length,root surface area,root volume,root dry weight and aboveground biomass by 21.3%,56.8%,47.3%,44.2%,41.2%and 13.6%,respectively.There was significantly positive correlation among root capacitance(EC)and root morphologies(R2=0.459-0.809**)and grain yield(R2=0.808**),while root electrical impedance(EI)and root morphologies(R2=0.289-0.523**)and grain yield(R2=0.647**)showed significantly negative correlation.The effect of delayed sowing on root length,root surface area,root volume,root dry weight,aboveground biomass and grain yield in plants of rape was significant.So the appropriate sowing date is the important agronomic factor for sustaining the high yield of rape.In addition,the electrical measurement method,such as EC/EI,as a rapid and non-destructive root detection technology,can be applied in agronomic management and variety selection for improving the root morphologies and seed yield.