干旱胁迫下AM真菌对矿区土壤改良与玉米生长的影响

以神东矿区塌陷区退化土壤为供试基质,以玉米为宿主植物,研究在干旱胁迫下,丛枝菌根真菌(arbuscular mycorrhizal fungi)对玉米生长和养分吸收的影响,以及对矿区退化土壤的改良作用。结果表明:干旱胁迫下,接种AMF显著提高了玉米根系侵染率和生物量,玉米叶片相对含水量和叶色值明显高于对照组;接种组玉米地上部分磷、氮、钙和根系部分磷、钾、钙含量显著增加;接种AMF后,玉米根际土壤总球囊霉素和易提取球囊霉素含量分别增加了36.2%和33%,且根际土壤中有机质含量显著增加。由此可见,接种AMF促进了玉米对矿质养分的吸收,缓解了干旱造成的玉米生长的不利影响,提高了根际土壤中有机质含量,对矿区退化土壤改良有重要意义。

Effects of AMF on soil improvement and maize growth in mining area under drought stress

Shendong mining area is one of the largest coalfield and the most important coal production base in China. Water is an important limiting factor of ecological and environmental protection in this area which belongs to the typical semi-arid, semi-desert plateau continental climate. Underground mining is the main form of coal mining, which would inevitably lead to ground subsidence. Surface moisture and nutrient loss form a large number of cracks were caused by the process. Water shortage have become a serious problem in mining area. However water is necessary for biological survival. Lack of water would hinder the growth of crop and exacerbate the agricultural drought. Arbuscular mycorrhizal fungi (AMF) is a ubiquitous symbiotic fungi. The symbionts body could be formed by AMF with more than 80% of terrestrial plant. It find that using AMF could promote to absorb mineral nutrients and water by plant, enhance the stress resistance and disease resistance of corn, improve the soil structure, increase the soil fertility, raise the survival rate of seedlings transplanting and ameliorate the vegetation restoration of land reclamation in coal mining subsidence area. Under drought stress condition, with maize and degraded soil as the host plant and matrix, effects of arbuscular mycorrhizal fungi(AMF)on the growth and nutrient absorption of maize and the degraded soil in Shendong mine area were studied. The results showed that the treatment of inoculated AMF significantly increased the biomass and the root colonization rate of maize. Leaf relative water content and leaf color readings significantly higher than the control. The content of P, N, and Ca in shoot and the content of P, K, and Ca in root portion of maize of vaccinated treatments increased significantly. After inoculation with AMF,the phosphorus nutrition for maize was particularly improved. The phosphorus content in aerial parts of corn of inoculation treatments were on average of 0.17g/kg higher than that of non inoculation treatments and in roots were on average of 0.24 g/kg. Compared with the control, the content of total glomalin and easily extractable glomalin increased by 36.2% and 33% respectively. The content of organic matter in rhizosphere soil also significantly increased. It indicated that the soil inoculated AMF promoted the mineral nutrient absorption by maize and relieved the negative effect of drought on the growth of maize and raised the content of organic matter in rhizosphere soil, which having important meaning on improvement degraded soil in mining area. Using AMF reclamation is conducive to agricultural production and has important meaning for environmental restoration and ecological restoration in Shendong coal mining subsidence area.