AM真菌对煤矿沉陷区不同复合基质上紫花苜蓿生长和生理特性的影响

Effects of AM fungi on growth and physiological characteristics of Medicago sativa in different composite substrates in coal mining subsidence areas

关键词:  丛枝菌根真菌(AMF), 煤矿废弃物, 紫花苜蓿, 生长, 抗氧化系统, 渗透调节物质

Key words:  arbuscular mycorrhizal fungi(AMF), coal mine waste, Medicago sativa, growth, antioxidant system, osmotic adjustment substance

摘要:

该研究采用盆栽试验法,以紫花苜蓿(Medicago sativa)为材料,将煤矸石(CG)、粉煤灰(FA)和沙土(SS)按不同质量配比设置T1(CG:FA:SS=75%:25%:0%)、T2(CG:FA:SS=60%:25%:15%)、T3(CG:FA:SS=45%:25%:30%)、T4(CG:FA:SS=30%:25%:45%)四组混合基质以模拟,并以T5(CG:FA:SS=0%:0%:100%)为对照,AM真菌选用摩西斗管囊霉(F.m)和幼套近明球囊霉(C.e),通过单接菌和混合接菌,探索其对紫花苜蓿根系的侵染率、幼苗生长、抗氧化物酶活性和渗透调节物质变化的影响。结果表明:(1)在五组基质上,接种AM真菌显著提高了紫花苜蓿根系的菌根侵染率和菌根依赖性,且基质T4接种F.m+C.e[F.m:C.e=1:1(W/W)]的值最大(64.31%和86.24%)。(2)接种AM真菌不同程度提高了紫花苜蓿株高、基径、叶面积和生物量,且混合接菌的效果优于单接菌。(3)基质中填加过量煤矿废弃物抑制了植株根系的生长,接种AM真菌后显著提高了紫花苜蓿总根长、根表面积、根体积,降低了根平均直径。(4)不同接菌处理的紫花苜蓿叶片POD、SOD、CAT活性以及可溶性糖、可溶性蛋白含量总体表现为F.m+C.e>C.e>F.m>non-AMF,且接种F.m+C.e的增长幅度最大。研究表明煤矿废弃物复合逆境抑制紫花苜蓿的生长,接种AM真菌显著提高了幼苗生长、抗氧化物酶活性和渗透调节物质,提高了植物抗逆性能,且以基质T4接种F.m+C.e的效果最佳。

Abstract:

To improve the growth and survival race of plants in coal mine waste, potting experiment in greenhouse was carried out to explore the effects of single and mixed inoculation with AM fungi( Funneliformis mosseae, F.m and Claroideoglomus etunicatum, C.e)on the mycorrhizal colonization rate, seedling growth, antioxidant enzyme activity and osmotic adjustment substances of Medicago sativa in different compound substrates. The compound substrates were formed by mixing coal gangue(CG), fly ash(FA)and sandy soil(SS)mixed in different proportions T1(CG:FA:SS=75%:25%:0%), T2(CG:FA:SS=60%:25%:15%), T3(CG:FA:SS=45%:25%:30%), T4(CG:FA:SS=30%:25%:45%)and T5(CG:FA:SS=0%:0%:100%)was taken as control. The results were as follows:(1)Inoculation of AM fungi significantly increased the mycorrhizal colonization rate and mycorrhizal dependency of M. sativa's root in five different compound substrates. However, the maximum mycorrhizal colonization rate and mycorrhizal dependency after inoculation of F.m+C.e [F.m:C.e=1:1(W/W)](64.31% and 86.24%)occurred in T4 substrate.(2)Inoculation with AM fungi increased height, stem diameter, leaf area and biomass of M. sativa to some degrees, and the effects of mixed inoculation were better than that of single inoculation.(3)Growth of plant roots were inhibited by excessively adding coal mine solid waste. However, inoculation of AM fungi could significantly promote total length, surface area and volume of root, and decreased root average diameter.(4)Comparative effects of different inoculation treatments on POD activity, SOD activity, CAT activity, soluble sugar content and soluble protein content of M. sativa leaves with were F.m + C.e > C.e > F.m>non-AMF, and the optimal effect was showed in inoculated with F.m + C.e. Our results suggested that growth of M. sativa was realistically inhibited in coal mine waste. However, AM fungi significantly enhanced resistance to stress by improved seedling growth, antioxidant enzyme activity, and osmotic adjustment substances, especially the combination of F.m+C.e and compound substrate T4 was the best.