THE GROWTH AND ACTIVITY OF WINTER-WHEAT ROOTS IN THE FIELD - NUTRIENT INFLOWS OF HIGH-YIELDING CROPS
THE GROWTH AND ACTIVITY OF WINTER-WHEAT ROOTS IN THE FIELD - NUTRIENT INFLOWS OF HIGH-YIELDING CROPS
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DOI：
10.1017/s0021859600061724
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发表时间：
1986-02-01
影响因子：
2
通讯作者：
BARRACLOUGH, PB
中科院分区：
文献类型：
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作者：
BARRACLOUGH, PB
养分流入量，即单位时间内每单位根长吸收的养分量，已被确定为几种冬小麦作物（cv。Hustler），谷物产量在8-11 t/ha（85% D.M.）范围内。流入量在4月或5月达到最大值，其值在13-34、0.5-1.6、3.5-13、0.9-1.8和0.35-0.60倍的范围内。氮、磷、钾、钙、镁分别为10-14摩尔/厘米根/秒。使用养分吸收模型计算土壤溶液中维持养分通过土壤扩散流入所需的浓度。对于九月播种的作物，该模型预测需要165 μ M N、14 μ M P和56 μ M K的土壤溶液浓度来维持观察到的最大流入量，而对于具有较大根系的九月播种的作物，需要106 μ M N、8 μ M P和36 μ M K的甚至更低的值。看来，养分输送不太可能限制生长在潮湿、肥沃土壤中的冬小麦作物的吸收，至少对总干物质高达约17吨/公顷的作物来说是这样。
Nutrient inflows, that is the amount of nutrient absorbed per unit root length per unit time, have been determined for several winter wheat crops (cv. Hustler) with grain yields in the range 8-11 t/ha (85% D.M.). Inflows reached a maximum in April or May with values in the range 13-34, 0.5-1.6, 3.5-13, 0.9-1.8 and 0.35-0.60 .times. 10-14 mol/cm root/sec for N, P, K, Ca and Mg respectively. The concentration in the soil solution necessary to maintain inflows by diffusion of nutrient through the soil was calculated using a nutrient uptake model. For an October-sown crop the model predicted that soil solution concentrations of 165 .mu.M N, 14 .mu.M P and 56 .mu.M K were needed to sustain the observed maximum inflows, whereas for a September-sown crop, with a larger root system, even lower values of 106 .mu.M N, 8 .mu.M P and 36 .mu.M K were needed. It appears that nutrient transport is unlikely to limit uptake by winter wheat crops growing in moist, well fertilized soils, at least for crops up to about 17 t/ha of total dry matter.