基于污染控制的小麦品种氮磷钾吸收与移除特征研究

Nutrient Absorption Characteristics and Removal from Soil with Different Wheat Varieties Based on Pollution Control

种植养分高效吸收利用的作物,可以减少农田养分损失,控制农业生产造成的面源污染。通过不同小麦（Triticum aestivum L.）品种对比试验,旨在筛选养分高效吸收利用的小麦品种并探索其调控机理。以南京地区近年来新育成的12个品种为材料,研究了不同品种氮、磷、钾吸收量及其在体内的分配,分析了影响养分吸收各因子的贡献,并计算了秸秆还田和不还田两种方式下小麦收获期从农田移除的养分量。同一肥料供应水平下,不同品种间整株养分吸收量存在显著差异。以植株氮、磷、钾吸收量作为指标进行聚类分析,12个育成的小麦品种中宁麦09-118属于高效吸收氮磷钾的品种。所有供试品种的氮、磷含量均以籽粒最高,其积累量分别占植株总吸收量的72.6%-77.6%和68.5%-72.9%。籽粒氮、磷积累量的高低主要取决于籽粒产量,其对氮、磷总吸收量的贡献率分别为73.1%和84.6%。收获时上中部秸秆中钾的残留量占植株吸钾总量的比例达到59.4%-69.2%。籽粒产量与植株氮磷吸收量具有高度的相关性。不同品种对氮、磷、钾的吸收比例相对固定,平均N/P、N/K的值分别为4.7和1.8。在秸秆还田方式下,小麦收获期从农田移除的N、P、K养分量分别为128.4、25.8、14.0 kg·hm^-2;在秸秆不还田方式下,小麦收获期从农田移除的N、P、K养分量分别为153.4、30.8、74.1 kg·hm^-2。两种方式从农田移除的钾量差异显著。宁09-118高产且吸收氮磷钾能力最强,应成为长江下游地区栽种小麦的首选。要减少农业面源污染,应根据不同品种的小麦吸肥特性及当地养分利用效率确定氮磷钾施用量,并且在确定钾肥施用量时,还应该考虑种植区域小麦的秸秆利用方式。

Planting crops with high nutrient use efficiency, can reduce nutrient losses from fields, thus controlling non-point source pollution caused by agricultural production. The objective of this study was to select the wheat varieties with high nutrient use efficiency and explore the regulation mechanism. Nutrient absorption and distribution of different wheat varieties were studied, and contribution of the factors impacting nutrient absorption were analyzed, in this study with 12 newly-bred varieties as experimental materials. Under the same fertilizer supply level, nutrient uptake of whole plant was significantly different among different varieties. Cluster analysis on N, P, K uptake indicated that wheat variety Ning09-118 belonged to the type of high absorption of nitrogen, phosphorus and potassium among 12 bred wheat varieties. Nitrogen and phosphorus contents were the highest in grain than other organs for all wheat varieties, and nitrogen and phosphorus uptake by grain accounted for 72.6%-77.6% and 68.5%-72.9% of total plant uptake, respectively. Nitrogen and phosphorus uptake depended mainly on the grain yield. The nitrogen and phosphorus uptake contributed rates were 73.1% and 84.6%, respectively. Upper and middle straw were main parts of potassium storage, which accounted for 59.4%-69.2% of plant potassium accumulation. Grain yield had high correlations with nitrogen and phosphorus uptake by plants. The absorption ratios of nitrogen, phosphorus, potassium were similar in the different varieties. The average ratios of nitrogen to phosphorus, and nitrogen to potassium were 4.7 and 1.8, respectively. Potassium removal caused by wheat harvest had significant difference between with and without the application of wheat straw to field. Ning 09-118 was preferred under the same level of fertilizer application, for its high yield and strong absorption capacity of nitrogen, phosphorus, and potassium. In order to decrease nutrient losses from fields, the application rates of nutrient, phosphorus and potassium should be decided by nutrient uptake characteristics of wheat varieties and nutrient use efficiency,and the determination of potassium fertilizer application should also consider the methods of straw utilization in wheat growing areas.