Dynamics Of Microbial Community And Fermentation Quality During Ensiling Of Forages With Exogenous Microorganism

The objective of this study was to evaluate the dynamics of microbial community and fermentation quality during ensiling of alfalfa and napier grass with Lactobacillus plantarum and exogenous microbiota.The y-ray irradiation was used to obtain sterile substrates and eliminated the interference effect of epiphytic microorganism on fermentation quality and microbial community.The application of high throughput sequencing helps us to better monitor the reconstitution mechanism of exogenous microbiota on the same substrate and their contributions on fermentation quality and microbial community during the alfalfa ensiling.It also provides a scientific and theoretical basis for developing pertinence microbial additives for silage,regulating the alfalfa and napier grass silage fermentation in practical production.1 Dynamics of microbial community and fermentation quality during ensiling of alfalfa with Lactobacillus plantarum inoculantThe objective of this study was to evaluate the dynamics of microbial community and fermentation quality during ensiling of sterile and nonsterile alfalfa with Lactobacillus plantarum inoculant.Alfalfa was ensiled directly(A1),after y-ray irradiation(AO),and after inoculation of the sterile(AOL)or fresh alfalfa(A1L)with Lactobacillus plantarum.The inoculation of Lactobacillus plantarum improve the fermentation quality of alfalfa regardless of the y-ray irradiation.The AOL had the higher lactic acid content and lower pH than that in A1L from 3 days of ensiling.Pediococcus was the dominant microbes in A1 silage,followed by Enterococcus and Lactobacillus,while Lactobacillus in A l L and AOL outnumbered all other genera at 3 d.In AOL silage,the relative abundance of Lactobacillus increased to 99.13%.Alfalfa silage inoculation with Lactobacillus plantarum increased the relative abundance of the dominated genus,Lactobacillus,reducing the diversity of the bacterial community and improving the fermentation quality.2 Dynamics of microbial community and fermentation quality during ensiling ofnapier grass with Lactobacillus plantarum inoculantThe objective of this study was to evaluate the dynamics of microbial community and fermentation quality during ensiling of napier grass with Lactobacillus plantarum inoculant.napier grass was ensiled directly(N1),after γ-ray irradiation(N0),and after inoculation of the sterile(N0L)or fresh napier grass(N1L)with Lactobacillus plantarum.The results showed that all treatments displayed lactic acid-type fermentation and high quality silages.The inoculation of Lactobacillus plantarum increased the lactic acid content,decreased the pH and acetic acid content regardless of the γ-ray irradiation,the N0L had the higher lactic acid content and lower pH and acetic acid content than that in N1L.Leuconostocs and Lactobacillus were the dominant microbes in N1 silage,while Lactobacillus in N1L and N0L outnumbered all other genera at 3 d,the relative abundance of Lactobacillus in N0L increased to 99.13%.napier grass silage inoculation with Lactobacillus plantarum increased the relative abundance of the dominated genus,Lactobacillus,decreased the relative abundance of Leuconostocs,increasing the lactic acid content and reducing the pH and acetic acid content.3 Effect of microbiota derived from napier grass on fermentation quality and microbial community succession in alfalfa silageThe objective of this study was to reveal the reconstitution mechanism of exogenous microbiota and their contributions on fermentation quality and microbial community during the alfalfa ensiling.Alfalfa was ensiled directly(A1),after y-ray irradiation(A0),and after inoculation of the sterile(A0N)or fresh alfalfa(A1N)with napier grass microbiota.Compared with A1,A1N showed lower lactic acid content,higher pH and ammonia-N,while AON showed higher LA content,lower pH and AN/TN.The inoculation of napier grass microbiota changed the microbial community succession,Enterococcus and Pediococcus dominated the natural silage fermentation of alfalfa(A1),Leuconostocs and Lactobacillus became the predominated genera in AON silages,while Lactobacillus,Leuconostocs,Enterococcus and Pediococcus constituted the majority of bacterial community in A1N silages.4 Effect of microbiota derived from alfalfa on fermentation quality and microbial community succession in napier grass silageThe objective of this study was to reveal the reconstitution mechanism of exogenous microbiota and their contributions on fermentation quality and microbial community during the napier grass ensiling.napier grass was ensiled directly(N1),after y-ray irradiation(N0),and after inoculation of the sterile(N0A)or fresh napier grass(N1A)with alfalfa microbiota.Inoculating alfalfa microbiota enhanced the lactic acid fermentation of napier grass regardless of sterile during the 7 days of ensiling.The higher acetic acid contents in N1 and N1A silages,inoculating alfalfa microbiota contributed to higher AN/TN regardless of sterile napier grass.The inoculation of alfalfa microbiota changed the microbial community succession,the natural fermentation of napier grass dominated by Leuconostocs and Lactobacillus,while NOA silage dominated by Pediococcus.