干旱胁迫下氮素对不同基因型小麦根系活力和生长的调控

发布时间：2019-04-23 08:39

【摘要】：为了探讨不同水氮耦合处理对小麦根系活力和吸收氮素能力的影响,以多穗型小麦品种西农979和大穗型小麦品系2036为材料进行营养液培养试验,设置正常水分供应、轻度和重度水分胁迫及低氮、中氮和高氮处理,研究了不同水氮耦合对小麦根系形态、根系吸收面积、根系活力、植株氮素积累量的影响。结果表明,水分与氮素存在着明显的互作效应,重度水分胁迫和低氮处理都会降低小麦的生物量、根系总吸收面积、活跃吸收面积和活力、氮含量和植株的氮素积累量,低氮处理增加了根长和根冠比。高氮处理的西农979根系总吸收面积、活跃吸收面积和活力较低,中氮处理显著提高,且分别比2036高11%、14%、27%。西农979在中氮和高氮处理之间的氮素积累量无显著性差异。中氮处理下西农979的植株氮素积累量比2036高13%~62%。相关分析表明,小麦的活跃吸收面积、根系活力与植株氮素积累量呈极显著正相关(P0.01),和根冠比呈极显著负相关(P0.01)。在轻度水分胁迫下,增加氮素供给能有效提高西农979的根系吸收面积和根系活力;过高的氮素不利于2036根系的生长,表明不同基因型小麦的根系活力和生长对不同水氮耦合的响应不同。通过适宜的水氮耦合调控,有利于创造良好的小麦根系形态,提高根系活力及对水分和养分的吸收能力。
[Abstract]:In order to study the effects of different water and nitrogen coupling treatments on root activity and nitrogen uptake ability of wheat, the nutrient culture experiments of Xinong 979 and large spike wheat line 2036 were carried out, and the normal water supply was set up. The effects of water and nitrogen coupling on root morphology, root absorption area, root activity and plant nitrogen accumulation in wheat were studied under mild and severe water stress and low nitrogen, middle nitrogen and high nitrogen treatments. The effects of water and nitrogen coupling on root morphology, root absorption area, root activity and plant nitrogen accumulation were studied. The results showed that there were obvious interaction effects between water and nitrogen. Both severe water stress and low nitrogen treatment could decrease wheat biomass, root total absorption area, active absorption area and activity, nitrogen content and nitrogen accumulation of plant, and the total absorption area of root, active absorption area and activity, nitrogen content and nitrogen accumulation of plant could be decreased by severe water stress and low nitrogen treatment. Low nitrogen treatment increased root length and root-shoot ratio. The total absorption area, active absorption area and activity of Xinong 979 root line treated with high nitrogen were lower than those of middle nitrogen treatment, which were 11%, 14% and 27% higher than those of 2036, respectively. There was no significant difference in N accumulation between middle N and high N treatment in Xinong 979. Under medium nitrogen treatment, the nitrogen accumulation of Xinong 979 was 13% higher than that of 2036, and the nitrogen accumulation of Xinong 979 was 13% higher than that of 2036. The correlation analysis showed that the active absorption area and root activity of wheat were positively correlated with nitrogen accumulation (P0.01) and negatively correlated with root / shoot ratio (P0.01). Under mild water stress, the root absorption area and root activity of Xinong 979 could be effectively increased by increasing nitrogen supply. Too high nitrogen was not conducive to the growth of 2036 roots, indicating that the response of root activity and growth to different water and nitrogen coupling was different in different genotypes of wheat (Triticum aestivum L.). Through the proper water-nitrogen coupling regulation, it is beneficial to create good root morphology, improve root activity and water and nutrient absorption capacity of wheat (Triticum aestivum L.).
【作者单位】：中国科学院水利部水土保持研究所/黄土高原土壤侵蚀与旱地农业国家重点实验室;
【基金】：国家自然科学基金项目(31370425,31501276) 国家科技支撑计划项目(2015BAD22B01)
【分类号】：S512.1

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