【作者】 王晓旭；

【导师】 刘灵；

【作者基本信息】 广西师范大学 ， 植物学， 2012， 硕士

【摘要】 本研究以大豆为研究对象,探讨了干旱条件下喀斯特地区碱性岩溶土与酸性土两种典型土壤中分别接种2号菌(Glomus mosseae,G.m),和13号菌(Glomus constrictum,G.c)两种AMF对大豆植株抗旱性的影响,研究结果如下：1.干旱胁迫下,大豆幼苗的菌根侵染率各指标(F%、M%、A%和V%)都显著低于正常浇水处理；相对于不接菌干旱处理,接菌干旱处理大豆的菌根侵染强度等指标均显著升高；比较两菌种间的菌根侵染强度,无论何种土壤,无论干旱与否,上述大豆的菌根侵染率4指标均为干旱接种G.m处理>干旱接种G.c；比较同一菌种在不同土壤间的侵染强度,不沦接种何种AMF菌种,无论干旱与否,上述大豆的菌根侵染强度4指标的变化趋势均是：酸性土处理>碱性土处理。2.干旱胁迫下,在碱性土与酸性土中接种两种AMF后,与相应的干旱不接菌对照相比,大豆植株叶片的相对含水量均有不同程度的提高,差异显著(P≤0.05),且接种G.m处理的相对含水量显著高于接种G.c处理,尤其是在酸性土中接种G.m处理保水能力最强。3.无论在碱性土与酸性土中,干旱处理下,接种AMF后,各处理大豆叶中的超氧阴离子(O2-)累积量和丙二醛(MDA)含量表现出相同的变化趋势：干旱不接种AMF处理>干旱接种G.c处理>干旱接种G.m处理；干旱下接种同一AMF菌种处理的大豆在不同土壤问O2-累积量和MDA含量的变化趋势为：酸性土处理<碱性土处理,差异均显著(P≤0.05)。对于O2-累积量来说,接种不同AMF处理间差异显著；而对MDA含量来说,则接种不同AMF处理间差异不显著。此外,大豆植株中三种保护酶(SOD、POD、CAT)活性的变化则为：干旱接种G.m处理>干旱接种G.c处理>干旱不接种AMF处理,接种同种AMF菌种处理的大豆SOD、POD、CAT活性表现为：酸性土处理>碱性土处理,不同土壤间差异显著(P≤0.05)。4.干旱胁迫下,接种AMF的大豆叶片中游离脯氨酸和可溶性糖含量均有不同程度的增加,但接种同种AMF处理的大豆在不同的土壤中脯氨酸的含量变化差异不大,而可溶性糖含量变化则差异显著；干旱条件下,无论何种土壤,大豆的游离脯氨酸含量和可溶性糖含量变化趋势均为：接种G.m处理显著>接种G.c处理,而接种同种AMF菌种处理的变化趋势则为：碱性土处理略>酸性土处理。5.与上述2中SOD活性变化趋势相似,在不同土壤中,与相应的干旱不接种对照组比,干旱胁迫下接种两种AMF处理的大豆NR活性均显著增加,尤其在酸性土中,干旱接种G.m处理的NR活性>干旱接种G.c处理；而与上述3中大豆叶片中的MDA含量变化趋势相似,干旱胁迫下,无论在何种土壤中接何种AMF,与相应的干旱不接菌处理比,其可溶性蛋白含量均显著降低,且干旱接种G.m<干旱接种G.c<干旱不接种CK；无论接菌与否,无论是否干旱处理,酸性土中大豆可溶性蛋白含量均<碱性土。6.干旱胁迫下,与干旱不接菌处理比较,干旱接种AMF后大豆植株叶绿素含量、叶片胞问CO2浓度和净光合速率显著提高,且在不同土壤中接种相同AMF处理问差异显著。其中,大豆的叶绿素含量、叶片胞间CO2浓度与净光合速率变化趋势为：干旱接种G.m处理显著>干旱接种G.c处理,而酸性土处理显著>相应的岩溶土处理且差异显著(P≤0.05)；此外,干旱胁迫下,大豆叶气孔导度和蒸腾速率变化趋势也与上述3中SOD活性变化趋势基本一致。7.干旱胁迫下,与干旱不接菌处理相比,接种AMF处理的大豆整株生物量和籽粒产量显著提高,且在同一土壤中接种不同AMF处理间差异显著。干旱接种G.m处理大豆的整株生物量和籽粒产量>干旱接种G.c处理>干旱不接种AMF处理,并在酸性土中各处理问差异显著；干旱下在不同土壤中接同种AMF处理间整株生物量和籽粒产量变化为：酸性土处理>碱性土处理,差异显著(P≤0.05),干旱胁迫下,酸性土中接种G.m处理的大豆整株生物量和籽粒产量最高。综上所述,干旱胁迫下,与不接种AMF对照相比,接种AMF后大豆植株的NR活性增强,超氧阴离子自由基(O2-和MDA含量降低,叶片中3种膜保护酶活性及几种渗透调节物质的含量提高,大豆植株的保水性、耐旱性增强,可缓解水分胁迫造成的伤害,大豆植株的光合速率等代谢活动维持较高水平,最终整株生物量和籽粒产量提高。此外,干旱接种G.m处理对大豆植株抗旱性的增强及生长的促进效应显著优于干旱接种G.c处理,Glomus mosseae (G.m)可作为喀斯特地区大豆生产中增强植株抗旱保水能力并提高产量的优势菌种之一。更多还原

【Abstract】 Using soybean (Glycine max) as research material, a potted experiment was conducted to explore the effects of Glomus mosseae (G.m) and Glomus constrictum (G.c) on drought resistance in two typical karst soil (alkaline soil and acid soil). The results show as follows:1. Under drought stress, the infection intensity (M%), infection frequency (F%) and arbuscular abundance (A%) of soybean root system inoculated with AMF were significantly decreased than that with normal water condition. On the contrary, comparing to no-AMF and drought treatment, the three infection rate indexes (M%, F%and A%) of soybean with AMF and drought treatment increased significantly; Comparing infection rate between two AMF species, no matter what kind of soil and water condition, the three infection rate indexes of soybean with G.m and drought treatment were more higher than that with G.c and drought treatment; Moreover, comparing infection rate between two typical karst soil, no matter what kind of AMF and water condition, the three infection rate indexes of soybean in acid soil were more higher than that in alkaline soil.2. Under drought stress, comparing to no-AMF treatment, the relative water contents of soybean inoculated with different AMF were increased significantly (P≤0.05).And the water holding capacity of soybean with G.m was stronger than with G.c, especially in acid soil.3. In alkaline soil and acid soil, the accumulation of superoxide anion free radical (SAFR) and malondialdehyde (MDA) of soybean with AMF under drought condition showed the tendence that:the cumulative amount of SAFR and MDA under drought stress without AMF treatment were the highest than that with G.c plus drought stress treatment and that with G.m plus drought stress treatment respectively, the cumulative amount of SAFR and MDA with G.m plus drought stress treatment were the lowest.Comparing cumulative amount of SAFR and MDA between two typical karst soil, that in acid soil were more lower than that in alkaline soil. Regarding the accumulation of SAFR, it showed significant differences among treatments with different AMF; For accumulation of MDA, there had no significant differences among treatments with different AMF; The trend of activity changes of protective enzyme of soybean, such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) indicated that: activities of3protective enzyme with G.m under drought stress> that with G.c under drought stress> that without AMF under drought stress. Inoculated with the same AMF, the activity changes of SOD,POD,CAT represented: Activities of3protective enzyme in acid soil> that in alkaline soil, and the differences of treatment were significant(P≤0.05).4. Under drought stress, comparing to no-AMF treatment, contents of free proline and soluble sugar with AMF treatment increased in different degree. Similar to change trend of SOD activity, content changes of free proline and soluble sugar with AMF treatment showed:that with G.m under drought stress> that with G.c under drought stress> that without AMF under drought stress,that in alkaline soil>that in acid soil.The differences of treatment were significant too (P≤0.05).5. Similar to change tendence of SOD activity, the activity of nitrate reductase (NR) with G.m under drought stress was higher than that with G.c under drought stress and that without AMF under drought stress. The activity of NR without AMF under drought stress was the lowest. Inoculated with the same AMF, the activity changes of NR in acid soil was higher than that in alkaline soil, and the differences of treatment were significant (P≤0.05). As for soluble protein, similar to change trend of MDA accumulation, content of soluble protein with AMF under drought treatment decreased significantly than that with no-AMF under drought treatment. Under drought stress, the content of soluble protein with G.m<that with G.c. And comparing two typical karst soil, the content of soluble protein in acid soil<that in alkaline soil.6. Under the water stress,comparing with drought treatment without AMF, the content of chlorophyll, intercellular CO2concentration and photosynthetic rate as well as the transpiration rate and stomata conductance of soybean all increased significantly, the change tendency of the5indexes above were similar to that of SOD. The differences of same index with different treatments were significant (P≤0.05).7. Comparing with drought treatment without AMF, the biomass (dry weight of the whole plant) and grain yield of soybean with AMF and drought treatment increased significantly.The change trend of biomass and grain yield indicated:that with G.m under drought stress> that with G.c under drought stress> that without AMF under drought stress. In another word, soybean which inoculated with G.m in the acid soil had highest biomass and grain yield under drought stress.Furthermore, biomass and grain yield of soybean in acid soil>that in alkaline soil.The differences of same index with different treatments were significant(P≤0.05).Anyhow, under drought stress, compared with treatment without AMF, soybean inoculated with AMF had a high NR activity. Accompanied by the decrease of SAFR and MDA content, protective enzyme activity and the amount of osmotic regulation substance (free proline and soluble sugar) enhanced. The facts mentioned above result in better water retention capacity and mineral nutrient absorption ability,as well as alleviation of the drought injury. Then the drought resistance of soybean improved, metabolic activity such as photosynthesis maintained a high level.Finally, the biomass and grain yield of soybean enhanced.Moreover, under drought condition, the promoting effect on drought resistance and growth of soybean with G.m was higher than that with G.c. It drew a conclusion that Glomus mosseae(G.m) can be used as one of the dominant candidate fungi for improving water holding ability,biomass and grain yield of soybean in the karst areas.更多还原