AM真菌、木霉和PGPR组合的促生效应研究

Study on Growth Promoting Effects of Co-inoculation with Different AM Fungi,Trichoderma harzianumsp. and Growth-promoting Rhizobacteria

丛枝菌根(AM)真菌、木霉(Trichoderma spp.)和根围促生细菌(PGPR)是重要的植物根系共生微生物。本试验于温室盆栽条件下研究了AM真菌摩西斗管囊霉 Funneliformis mosseae 、根内根孢囊霉 Rhizophagus intraradices 、哈茨木霉 Trichoderma harzianum LTR-2和巨大芽孢杆菌 Bacillus megaterium B130-1及其组合促进烟草(Nicotiana tabacum)品种CF90NF幼苗生长的效应及其作用机制。结果表明,供试组合均可促进烟草幼苗生长,以摩西斗管囊霉+哈茨木霉LTR-2组合作用最显著,摩西斗管囊霉+哈茨木霉LTR-2同时接种显著提高烟草植株总根长、根系总面积、根尖总数、根系活力以及叶片叶绿素含量、气孔导度和光合速率等指标,同时诱导叶片中生长素合成关键酶吲哚-3-乙酰胺水解酶基因 NtAMI1表达上调,提高叶片吲哚乙酸(IAA)含量。结论认为,摩西斗管囊霉+哈茨木霉LTR-2组合可促进烟草根系生长,改善植株的光合性能,提高植株IAA含量,进而促进植株生长。

Arbuscular mycorrhiza fungi (AMF),Trichoderma spp. and plant growth-promoting rhizobacteria (PGPR) are important microorganisms in rhizosphere. In this study,the effects of inoculation with different combinations of arbuscular mycorrhiza fungi (AMF) Funneliformis mosseae and Rhizophagus intraradices as well as Trichoderma harzianum LTR-2 and Bacillus megaterium B130-1 on the growth of tobacco seedling and the related functional mechanism were evaluated. The results displayed that all the co-inoculation with different combinations of tested microorganisms could prompt the growth of tobacco seedling. Moreover,the F. mosseae and T. harzianum LTR-2 combination exhibited the most significant positive effect. Co-inoculation with F. mosseae and T. harzianum LTR-2 significantly increased the total root length,root surface area,root volume and root activity,enhanced photosynthesis rate,stomatal conductance and chlorophyll content. This co-inoculation also up regulated the expression of indole-3-acetamide hydrolase gene NtAMI1 and the content of auxin (IAA) in tobacco leaves. It can be deduced that dual inoculation with F. mosseae and T. harzianum LTR-2 promoted tobacco growth though improving root development,photosynthetic capacity as well as IAA accumulation.