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在冬小麦‖早春玉米/夏玉米种植体系(“‖”与“/”分别表示间作和套作)中,研究了小麦根系数量与活性的空间分布特征及变化规律。主要结果:(1)高产田间作冬小麦最大根深200cm左右,160～200cm深层土壤根量持续增长至灌浆蜡熟期。(2)根系含水率自上而下由低向高变化,随生育进程推进,呈下降趋势。(3)根系鲜重自拔节期以后,0～80cm土层随生育进程推进呈减低趋势;80～160cm于开花期达最大值,之后下降;160～200cm土层到灌浆期和蜡熟期值最大。0～200cm土体总根干重于灌浆期值最大,之后下降。(4)拔节、开花、灌浆和蜡熟4次结果平均,0～20cm土体根鲜重和干重分别占到0～200cm总重的46.90%与47.63%,40cm以上占到57.90%与59.89%,80cm以上占77.00%与78.62%,120cm以上占到92.26%与93.07%,120cm以下土体占不足10%。根系重量密度自上而下可划分为0～20cm高密度区、20～120cm中密度区、120～160cm低密度区及160～200cm稀密度区。(5)根系TTC还原强度呈上大下小变化,0～160cm土体平均根活力拔节期较高,开花灌浆期下降,蜡熟期反弹上升。(6)拔节、开花、灌浆和蜡熟期四次结果平均,0～20cm土壤根系TTC还原总量占到0～160cm土体的53.84%,40cm以上占到66.01%,80cm以上占到83.40%,120cm以上占到94.77%,120～160cm深层土壤占5%左右。
In winter wheat / early spring maize / summer maize planting system ( “” and “/ ”, respectively, intercropping and intercropping), the spatial distribution characteristics and the variation of root activity and quantity were studied. The main results are as follows: (1) The maximum root depth of winter wheat in high-yielding field was about 200cm, and the root mass of deep soil in 160 ~ 200cm continued to increase to the filling wax maturity. (2) Root moisture content from low to high from top to bottom, with the progress of childbearing progress, showing a downward trend. (3) After 0 ~ 80cm soil layer of fresh weight increase and jointing stage of root system, the soil layer of 0 ~ 80cm decreased with the growth progress; the maximum of 80 ~ 160cm reached the flowering stage and then decreased; the soil layer of 160 ~ 200cm reached the filling and wax ripening stage maximum. The total root dry weight of 0 ~ 200 cm soil layer was the highest at filling stage and then decreased. (4) The results of jointing, flowering, grouting and wax ripening were the average of 4 times. The fresh weight and dry weight of 0 ~ 20cm soil accounted for 46.90% and 47.63% of the total weight of 0 ~ 200cm, 57.90% and 59.89 respectively over 40cm %, 80% or more accounted for 77.00% and 78.62%, 120% or more accounted for 92.26% and 93.07%, less than 120cm of soil accounted for less than 10%. Root weight density from top to bottom can be divided into 0 ~ 20cm high density area, 20 ~ 120cm medium density area, 120 ~ 160cm low density area and 160 ~ 200cm thin density area. (5) The TTC reduction intensity of root system showed a small change from big to small, the average root vigor of 0 ~ 160cm was higher at jointing stage, decreased at flowering filling stage and rebounded at waxy stage. (6) The results of four times of jointing, flowering, filling and wax ripening were average. The total amount of TTC reduction in 0 ~ 20cm soil accounted for 53.84% of 0 ~ 160cm soil, above 40cm accounted for 66.01%, 80cm accounted for 83.40% , 120cm above accounted for 94.77%, 120 ~ 160cm deep soil accounted for about 5%.