不同育成年份冬小麦苗期根冠生物量分配

Biomass Allocation of Root and Shoot of Wheat Seedlings in different Years

为探讨品种更替过程中小麦苗期根冠生物量分配的演变趋势,以历年来黄淮海麦区大面积推广种植的22个冬小麦品种为研究对象,采用砂培的方法进行幼苗培养,分析小麦种子萌发后不同时间根、冠生长及生物量分配的变化规律。结果表明:冬小麦种子萌发后第3天幼苗根数在品种间无显著差异,第9天、第15天随着品种更替的进行呈现出显著下降的趋势,现代品种初生根数目显著低于早期品种。在第3天、第9天、第15天,小麦苗期幼苗生长随品种更替呈现不同的变化趋势,芽长显著下降,但根长无显著差异。可见,冬小麦苗期芽干质量在品种改良过程中未发生明显变化,而根干质量和根冠比呈现出显著下降的趋势,冬小麦苗期现代品种地上部分分配到更多的生物量。

To explore the changing trends in biomass allocation to wheat root and shoot during the cultivar changes at seedlings stage,22 winter wheat cultivars which were widely promoted over the years in the area of Huanghe,Huaihe and Haihe rivers were taken as object,an experiment was conducted to analyze the change of wheat root and shoot growth,biomass allocation at different time after germination,and was arranged at seedling growth with sand culture.The root number of wheat seedlings had no significant difference at 3 days after germination,but showed a decreasing trend at 9 days and 15 days after germination over time.Primary root number of modern cultivars was significantly lower than that of old cultivars.Wheat seedling growth changed differently with change of cultivar.The shoot length greatly decreased,but root length had no significant difference.Wheat seedlings of old cultivars grew faster,which was the foundation of plant growth.Shoot dry mass of wheat seedlings showed no significant trend with change of year,while root dry mass showed a decreasing trend over time,and the same as root shoot ratio.Modern cultivars had an increased biomass allocation to shoots compared to root biomass allocation.