The Effect Of Funneliformis Mosseae On AM Fungi Diversity And Quality In Continuous Cropping Soybean Roots

The continuous cropping of soybean in our country had existed and the acreage of continuous cropping had accounted for 20%of the soybean sowing area,which has caught people’s great attention.Continuous cropping is the major limiting factor for agricultural production.In order to improve the disease resistance of soybean continuous cropping and the output and quality of soybeans,especially the prevention of root rot of soybean continuous cropping,this experiment,which is conducted by inoculating Funneliformis mosseae to the northeastern continuous cropping with different genes exploring the diversity of AM fungi’s microbial community structure and its impact on the quality of soybeans,can lay a theoretical foundation for the prevention of root rot of soybean continuous cropping by AM fungi and the improvement of soybean output and quality and provide technological support for seeking new technologies.1.The rate of AM fungi infecting into different soybean varieties in birth period by dissociation alkali-acid fuchsin staining demonstrates that in birth period AM fungi infection rate varies with the length of continuous cropping.After the three soybean varieties were inoculated with AM fungi,in both seedling stage and sprouting stage they show:the infection rate of continuous cropping for two years is generally higher than that of continuous cropping for one year and the first year cropping,that is to say,infection rate rises with increase of the length of continuous cropping.2.Combined the traditional morphological method with nested-PCR-DGGE,the research studies the impact of Funneliformis mosseae on the diversity of AM fungi microbial community structure of soybean root system and the results show that,the the flora on the sequenced 11 bands belong to the AM fungus,advantageous AM fungi in root of test samples are divided into two kinds,one kind is Funneliformis mosseae;the other kind is sticky Glomus viscosum of AM fungi,and from the sequencing results,the dominant AM fungi microbial community structure in root flora structure is Funneliformis mosseae,showing that the inoculated Funneliformis mosseae is the main AM fungi to infect the soybean root system.3.According to the analysis of DGGE spectra,the factors of the soybean varieties,different growth stages and length of continuous cropping had effects on the diversity of AM fungi of the soybean root system.The abundance,dominance and diversity index of AM fungi of the soybean root system are significantly different.4.Isoflavones,saponins,fatty acid content of soybean seed was measured by UV spectrophotometer method,organic solvent extraction and gas chromatography The results showed that:the content of total isoflavones of the same varieties of different lengths of continuous cropping,KF16 in L1 was high,HN44,HN48 in L2 were higher,compared with the fact that the CK has reached the first years of cultivation level;the content of total isoflavones of the same length of continuous cropping of different varieties,high oil variety(HN44)is the highest,intermediate varieties(KF16)is slightly higher than the high protein varieties(HN48);the content of total isoflavones of continuous cropping of different varieties,HIN44 and HN48 increased with the length of continuous cropping,KF16 increases first with the increase of the length of continuous cropping and then decreased.The content of total saponin in different lengths of continuous cropping of the same varieties,the total saponin content in KF16,HN44,HN48 respectively in L2,L1,CK is very high,the effect of inoculation of F.mosseae on the two varieties of KF16 and HN44 is significant;the total saponin content of the same length of continuous cropping of different varieties is different;the content of total saponin in different lengths of continuous cropping of different varieties varies with the change of different varieties.The content and type of fatty acid in different lengths of continuous cropping of the same variety was not reduced with the increase of the length of continuous cropping,the change is not great compared with CK;the content of fatty acid in the same length of continuous cropping of different varieties,HN44 was higher than other varieties,this phenomenon is very obvious;the type of fatty acid in different lengths of continuous cropping of different varieties remained the same,but the content varied greatly.The above results show that effect of F.mosseae on the three kinds of nutrient content is different,inoculation of F.mosseae can weaken the effect of continuous cropping on the quality of soybean.