5种豆科绿肥作物种子萌发期与苗期的抗旱性研究

Study on drought resistance during seed germination and seedling stage of five leguminous green manures

摘要:

【目的】本文围绕绿肥作物抗旱性的研究，为筛选出适宜干旱地区的绿肥品种提供理论依据。【方法】以毛苕子（Vicia villosa）、光叶紫花苕（V. villosa var. glabresens）、紫云英（Astragalus sinicus）、草木樨（Melilotus officinalis）、箭筈豌豆（V. sativa）5 种绿肥作物为研究对象，设置 0%、5%、10%、 15% 和 20% 的聚乙二醇（PEG-6000）高渗溶液模拟干旱胁迫，萌发期测定发芽率、发芽势并计算萌发指数、抗旱指数和隶属函数值，苗期测定可溶性糖、脯氨酸、丙二醛含量以及电导率等指标，计算隶属函数值。【结果】 PEG-6000 浓度为 5% 和 10% 时，除箭筈豌豆外，其他绿肥作物的发芽率均高于对照，说明低浓度的 PEG-6000 对种子萌发具有一定的促进作用。随着胁迫浓度的升高，5 种绿肥作物的发芽率、发芽势、萌发指数及抗旱系数不断下降，根据隶属函数综合分析评估指标值得出 5 种绿肥种子抗旱性顺序为：紫云英＞草木樨＞光叶紫花苕＞箭筈豌豆＞毛苕子。苗期可溶性糖含量、脯氨酸含量、丙二醛含量及电导率与对照相比均有所升高，其中草木樨的可溶性糖与丙二醛含量相比对照分别增加了 16. 27 mg/g 和 0. 39 μmol/g，毛苕子、光叶紫花苕的脯氨酸含量增加幅度较大，与 CK 相比较脯氨酸增加量分别为 46. 13 μg/g、31. 03 μg/g，毛苕子的电导率较 CK 增加 22. 06%，在 5 种豆科绿肥中增加量最大，苗期各指标整合分析显示抗旱性强弱顺序为：箭筈豌豆＞毛苕子＞草木樨＞光叶紫花苕＞紫云英。 【结论】综合萌发期及苗期 5 种绿肥作物的抗旱性，箭筈豌豆、光叶紫花苕这 2 种绿肥作物较草木樨、紫云英、毛苕子更适宜在干旱缺水地区推广种植。

Abstract:

【Objectives】 Drought significantly affects crop growth and yield，making the improvement of crop varieties’ drought resistance a crucial aspect of contemporary agricultural research. This experiment delved into the drought resistance of green manure crops to provide a theoretical foundation for selecting green manure varieties in arid areas.【Method】 Five green manure crops，i. e. Vicia villosa，V. villosa var. glabbresens，Astragalus sinicus， Melilotus officinalis and V. sativa，were studied. Hyperosmotic solutions of 0，5%，10%，15%，and 20% PEG‐6000 were employed to simulate drought stress. Germination rate and potential were measured during the germination stage，while germination index，drought resistance index，and membership function were calculated. At the seedling stage，soluble sugar，proline，malondialdehyde，and electrical conductivity were determined，and the membership function was calculated.【Result】 The results showed that except for V. sativa，the germination rate of other green manure crops was higher than the control at 5% and 10% PEG‐6000 concentrations，suggesting that low PEG‐6000 concentrations promoted seed germination to some extent. However，stress concentration increased，the germination rate， potential，index，and drought resistance coefficient of the five green manure seeds decreased continuously. Evaluation index values suggested the drought resistance order as follows：A. sinicus＞M. officinalis＞V. villosa var. glabbresens ＞V. sativa＞ V. villosa. At the seedling stage，the activity of soluble sugar，proline，malondialdehyde，and electrical conductivity increased compared to the control. The soluble sugar and malondialdehyde content increased by 16. 27mg/g and 0. 39μmol/g compared with the control，respectively. V. villosa and V. villosa var. glabbresens exhibited a notable increase in proline content compared to the control，with V. villosa showing a 46. 13 μg/g increase and V. villosa var. glabbresens a 31. 03 μg/g increase. The electrical conductivity of V. villosa increased by 22. 06% compared with CK，and the increase was the largest among the five legumes. The integration analysis of indexes indicated the drought‐resistance order as V. sativa＞V. villosa＞M. officinalis＞V. villosa var. glabbresens＞A. sinicus 【Conclusions】 The study concluded that V. sativa and V. villosa var. glabbresens are more suitable for cultivation in arid and waterscarce areas compared to M. officinalis，A. sinicus and V. villosa.