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In this study, the effects of epiphytic microbiota from different forages on the fermentation characteristics and microbial community structure of forage sorghum silage were investigated. The gamma irradiated sterilized forage sorghum was treated through sterile water, epiphytic microbiota of forage sorghum (FSm), Sudan grass (SDm), Napier grass (NPm), and maize (MZm). NPm and SDm inoculated silages showed similar pH value and lactic acid (LA) and acetic acid (AA) contents at day 3 and 60 of ensiling. The final silage of FSm and MZm showed lower (p < 0.05) pH and AA content and a higher LA content compared to the NPm and SDm silages. Bacterial species from the Weisella genus were predominantly present in FSm, NPm, and SDm, while Lactococcus dominated the MZm silage during early ensiling. Lactobacillus was predominant in all inoculated terminal silages. Overall, the four inoculated microbiota decreased the pH value of silage and were dominated by lactic acid bacteria (LAB); however, the NPm and SDm treatments resulted in comparatively higher AA contents which could have an inhibitory effect on the secondary fermentation developed by the yeast and enhanced the aerobic stability of forage sorghum silage. [ABSTRACT FROM AUTHOR]

Aims: To investigate the effects of epiphytic microbiota from napiergrass and Sudan grass on ensiling characteristics and microbial community of oat silage. Methods and Results: By γ‐ray irradiation sterilization and microbiota transplantation technology, the sterilized oat was inoculated as follows: (a) aseptic water (STOT), (b) epiphytic bacteria on oat (OTOT), (c) epiphytic bacteria on napiergrass (OTNP) and (d) epiphytic bacteria on Sudan grass (OTSD). STOT remained in the unfermented state based on similar chemical components with fresh oat. Compared with OTOT and OTSD, higher lactic acid content and ratio of lactic acid to acetic acid, and lower pH, acetic acid and ammonia nitrogen contents were observed in OTNP after 60 days of ensiling. At the late stage, Lactobacillus was the most predominant in each group. Lactococcus was eventually replaced by Lactobacillus in OTSD, whereas Lactococcus was found throughout the whole ensiling process in OTNP. Higher abundance of Weissella was observed in OTSD at the early and late stages. The result of co‐occurrence network analysis proved that Lactococcus was pivotal in determining the silage fermentation pattern during ensiling. According to the 16S rRNA gene‐predicted functional profiles, the inoculation of epiphytic microbiota from oat enhanced the metabolism of amino acids, whereas the inoculation of epiphytic microbiota from napiergrass and Sudan grass accelerated the carbohydrate metabolism. Conclusions: The epiphytic microbiota on napiergrass promoted a homo‐fermentative process, whereas the epiphytic microbiota on oat and Sudan grass facilitated a hetero‐fermentative pattern in oat silage, which was closely related to the abundance and metabolism of Lactococcus, Weissella and Lactobacillus. Significance and Impact of the Study: The exogenous microorganisms that promote the carbohydrate metabolism and inhibit the metabolism of amino acids could be a good potential source to improve the silage quality of temperate grass. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of epiphytic microbiota from Italian ryegrass (IRIR), Napier grass (IRNP) and Sudan grass (IRSD) on ensiling characteristics and microbial community of Italian ryegrass silage. Each treatment was prepared in triplicate and ensiled in plastic bag silos for 1, 3, 7, 14, 30 and 60 days. The γ-ray irradiation sterilization method, microbiota transplantation and next generation sequencing technology were used. Results indicated that significantly (P < 0.05) higher ratio of lactic acid to acetic acid, and lower acetic acid and ammonia nitrogen contents were observed in IRNP than IRIR and IRSD after 60 days of ensiling. Lactobacillus was the most predominant in each treatment at the late stage of fermentation. Lactococcus was eventually replaced by Lactobacillus in IRSD, whereas higher abundance of Lactococcus was continuously found in IRNP. Co-occurrence network analysis demonstrated Lactococcus was pivotal in determining the silage fermentation pattern of Italian ryegrass. According to the 16S rRNA gene-predicted functional profiles, the metabolism of amino acids was enhanced by the epiphytic microbiota from Italian ryegrass and Sudan grass, while the carbohydrate metabolism was accelerated by the epiphytic microbiota from Napier grass. Overall, IRNP had a homo-fermentative process, whereas IRIR and IRSD possessed a hetero-fermentative pattern. The Lactococcus and heterofermentative Lactobacillus were mainly responsible for this. It also confirmed that the exogenous microorganisms that promote the carbohydrate metabolism and inhibit the metabolism of amino acids could be a good potential source to improve the silage quality of temperate grass. [ABSTRACT FROM AUTHOR]