模拟根层障碍条件下不同深度玉米根系与产量的关系研究

在池栽条件下采用模拟根层障碍的方法,研究不同深度根系与玉米生长和产量的关系。结果表明,根层阻隔显著降低玉米根系的生物量、总根长和根表面积,各处理光合生产能力和子粒产量显著低于无阻隔(对照);随着阻隔层的下移,根系和冠层各指标和产量受到的影响逐渐变小,0~20、21~40、41~60、61~80、80 cm以下各层根系对产量的相对贡献率分别为52%、11%、7%、12%、19%。20 cm耕层以下根系对产量的贡献达48%,其中60cm以下土层内根系对产量的贡献达31%,说明深层根系虽然生物量占总生物量比例很小,但其在花粒期对深层水肥的吸收利用对产量形成具有重要作用。

Relationship of Roots in Different Soil Strata and Yield of Maize under Simulated Obstacle of Root Layer

In order to clarify the relationship of roots in different soil strata and yield of maize, an experiment with simulated root-layer obstacles in field pools was conducted. The result showed that root indexes including root biomass, total root length and root surface area, canopy photosynthesis capacity and yield of root limited treatments were significantly lower than that of control(without root limited). The relative contribution of roots in 0-20 cm, 21-40 cm, 41-60 cm, 61-80 cm and below 80 cm soil strata were calculated from the yield losses compared to control, which separately were 52%, 11%, 7%, 12% and 19%. This indicated that root below the 20cm plowing layer contributed 48% to maize yield, in which the root below 60 cm soil layer contributed 31% to maize yield. This result manifested that deep roots played an important role to maize yield by uptaking water and nutrition during post-anthesis period with relative smaller proportion to total root biomass.