水分胁迫下紫花苜蓿根源信号ABA应旱机制及其调控模型研究

发布时间：2018-04-30 05:23

本文选题：紫花苜蓿 + 亏缺灌溉　；参考：《中国农业科学院》2016年博士论文

【摘要】：随着可利用的农业水资源逐渐变的稀缺,迫切需要采用有效的灌溉管理措施来应对。亏缺灌溉就是其中一项有效的节水措施。本项研究对紫花苜蓿的形态特征,生理生化指标和产量对水分亏缺的响应规律进行了研究。实验于2014年9月至2015年5月在中国农业科学院的温室中开展,对敖汉,中苜一号和三得利3个紫花苜蓿品种,在四个亏缺灌溉梯度下(分别为田间持水力的100%(w1)(对照),85%(w2),70%(w3)和55%(w4))的形态特征,生理、生化指标和产草量进行了研究,主要结果总结如下:(1)紫花苜蓿形态特征和产草量随着亏缺灌溉程度增加而降低。和对照相比,W4处理的株高,分枝数、茎直径和地上部部分干重分别降低了45.95%,25.41%,34.38%和67.92%。此外,不同品种的株高、茎直径、开花期和地上部分重量对亏缺灌溉的响应存在差异。相对于其它两个品种,中苜一号株高最高为48.16cm,直径最宽为2.29 mm,开花期最早为第198 d,单株重量最高为20.41g/plant。(2)亏缺灌溉处理影响着生长季不同阶段的紫花苜蓿根系中ABA的含量。除了移栽后的第90天和105天,从移栽到收获阶段,所有处理根系中的ABA持续增加。增加亏缺灌溉程度显著增加根系中ABA的含量。移栽后的第105天,W1处理的ABA含量最低,为44 ng/g.FW,然后依次是W2的56.6ng/g.FW,W3的64.6ng/g.FW和W4的94.4ng/g.FW。此外,不同品种中ABA含量对水分胁迫的响应不同,移栽后105天,中苜一号、三得利和敖汉3个品种的最大的ABA含量分别为49.9ng/g.FW,61.7ng/g.FW和83.2ng/g.FW。相对于对照,水分胁迫最高的W4处理,根系长度减少20.92%,侧根减少20.71%,根系鲜重减少43.79%,根系干重减少37.96%。此外,相对于对照,水分胁迫处理根茎比增加1.9倍,表明苜蓿根系比地上部分对水分胁迫更敏感。(3)亏缺灌溉处理影响着生长季不同阶段的紫花苜蓿体内的ABA、MDA、SOD和糖的含量。除了移栽后的第90天和105天,从移栽到收获阶段,所有处理叶片中的ABA持续增加。增加亏缺灌溉程度显著增加叶片中ABA的含量。移栽后的第105天,W1处理的ABA含量最低,为133.2 ng/g.FW,然后依次是W2的138.1ng/g.FW,W3的141.7ng/g.FW和W4的145.ng/g.FW。此外,不同品种中ABA含量对水分胁迫的响应不同,移栽后105天,中苜一号、三得利和敖汉3个品种的最小ABA含量分别为135.3ng/g.FW,138.8ng/g.FW和145.1 ng/g.FW。不同生长阶段,MDA和SOD的活性受到亏缺灌溉处理的影响。增加亏缺灌溉程度显著增加MDA和SOD酶活性。MDA酶活性高的时期是在移栽后的105和120天,SOD活性最高的时期在移栽后105天。此外,增加亏缺灌溉程度也会增加可溶性糖含量,在移栽后105天可溶性糖含量最低。不同品种中MDA、SOD和可溶性糖含量对水分胁迫的响应不同,中苜一号的各项指标数值最低,而敖汉的数值最高。由此可见,亏缺灌溉会造成紫花苜蓿形态特征和草产量变小和降低。苜蓿根系比地上部分对水分胁迫更敏感。移栽后105天,苜蓿体内ABA含量最低;移栽后105天和120天,MDA酶的活性最高;移栽后105天,SOD酶的活性最高。因此,移栽后105天和120天做为苜蓿灌溉的关键时期。敖汉苜蓿根系中ABA含量和叶片中的ABA、SOD,MDA和可溶性糖含量均是最高,且开花期较晚,表明其抗旱性能显著高于中苜一号和三得利苜蓿。
[Abstract]:As the available agricultural water resources are becoming scarce, effective irrigation management measures are urgently needed. Deficit irrigation is one of the effective water-saving measures. In this study, the morphological characteristics, physiological and biochemical indexes and the response of the yield to the water deficit were studied in this study. The experiment was conducted from September 2014 to 2. In the greenhouse of Chinese Academy of Agricultural Sciences in May 015, the morphological characteristics, physiological, biochemical indexes and grass yield of Aohan, middle alfalfa and 3 alfalfa varieties were studied under four deficit irrigation gradients (100% (W1), 85% (W2), 70% (W3) and 55% (W4)). (1) the morphological characteristics and yield of Alfalfa decreased with the increase of deficit irrigation. Compared with the control, the height of plant, the number of branches, the diameter of the stem and the dry weight of the part of the upper part of the ground decreased by 45.95%, 25.41%, 34.38% and 67.92%., respectively. The plant height, the straight diameter of the stem, the flowering period and the weight of the aboveground partial weight on the deficit irrigation were stored in W4. In contrast to the other two varieties, the highest height of the one plant is 48.16cm, the width of the diameter is 2.29 mm, the earliest flowering time is 198th D, the maximum of the single plant weight is 20.41g/plant. (2), which affects the content of ABA in the root of Alfalfa at different stages of the growing season. Except for the ninetieth and 105 days after transplanting, from transplanting to harvest. At the stage, the ABA in all root systems increased continuously. Increasing the deficit irrigation degree significantly increased the content of ABA in the root system. After 105th days of transplanting, the ABA content in W1 treatment was the lowest, 44 ng/g.FW, followed by W2 56.6ng/g.FW, W3 64.6ng/g.FW and W4 94.4ng/g.FW., and the response of the ABA content to water stress in the different varieties was different, 105 days after transplanting, the maximum ABA content of 3 varieties of middle alalone, Suntory and Aohan were 49.9ng/g.FW, 61.7ng/g.FW and 83.2ng/g.FW. relative to the control. The root length decreased by 20.92%, the root length decreased by 20.71%, the root fresh weight decreased by 43.79%, the root dry weight decreased by 43.79%, and the root dry weight decreased by 37.96%.. The root and stem ratio increased by 1.9 times, indicating that the root of alfalfa was more sensitive to water stress than the upper part of the ground. (3) the deficit irrigation treatment affected the content of ABA, MDA, SOD and sugar in Alfalfa at different stages of the growing season. In addition to the ninetieth and 105 days after transplanting, the ABA in all treatments increased continuously. The degree of deficit irrigation significantly increased the content of ABA in leaves. The ABA content of W1 treated at 105th days after transplanting was 133.2 ng/g.FW, followed by W2 138.1ng/g.FW, 141.7ng/g.FW and W4 145.ng/g.FW. of W3, and the response of ABA content to water stress in different varieties was different, 105 days after transplanting, middle alalli and Aohan 3 in 105 days after transplanting. The minimum ABA content of the varieties was 135.3ng/g.FW, 138.8ng/g.FW and 145.1 ng/g.FW. at different growth stages. The activity of MDA and SOD was affected by the deficit irrigation treatment. The period of increasing the deficit irrigation degree significantly increased the activity of MDA and SOD enzyme activity.MDA enzyme activity higher than that after the 105 and 120 days after transplanting, and the SOD activity was the highest at 105 after transplanting. In addition, increasing the deficit irrigation degree also increased the soluble sugar content, and the soluble sugar content was the lowest in 105 days after transplanting. The response of MDA, SOD and soluble sugar content to water stress in different varieties was different, and the index values of middle alfalfa 1 were the lowest, but the number of Aohan was the highest. Thus, the deficit irrigation would cause alfalfa shape. The state characteristics and grass yield became smaller and lower. The root of alfalfa was more sensitive to water stress than the upper part of the ground. The ABA content of alfalfa was the lowest in 105 days after transplanting. The activity of MDA enzyme was the highest at 105 and 120 days after transplanting. The activity of SOD enzyme was the highest at 105 days after transplanting. Therefore, the key period of Alfalfa irrigation was 105 days and 120 days after transplanting. The content of ABA and the content of ABA, SOD, MDA and soluble sugar in the leaves were all the highest, and the flowering period was late, indicating that the drought resistance was significantly higher than that of the middle alfalfa and the middle alfalfa.

【学位授予单位】：中国农业科学院
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S541.9

【参考文献】