Whole-plant corn silage is a predominant forage for livestock that is processed in Heilongjiang province (Daqing city and Longjiang county), Inner Mongolia Autonomous Region (Helin county and Tumet Left Banner) and Shanxi province (Taigu and Shanyin counties) of North China; it was sampled at 0, 5, 14, 45 and 90 days after ensiling. Bacterial community and fermentation quality were analysed. During fermentation, the pH was reduced to below 4.0, lactic acid increased to above 73 g/kg DM (p < 0.05) and Lactobacillus dominated the bacterial community and had a reducing abundance after 14 days. In the final silages, butyric acid was not detected, and the contents of acetic acid and ammonia nitrogen were below 35 g/kg DM and 100 g/kg total nitrogen, respectively. Compared with silages from Heilongjiang and Inner Mongolia, silages from Shanxi contained less Lactobacillus and more Leuconostoc (p < 0.05), and had a separating bacterial community from 14 to 90 days. Lactobacillus was negatively correlated with pH in all the silages (p < 0.05), and positively correlated with lactic and acetic acid in silages from Heilongjiang and Inner Mongolia (p < 0.05). The results show that the final silages had satisfactory fermentation quality. During the ensilage process, silages from Heilongjiang and Inner Mongolia had similar bacterial-succession patterns; the activity of Lactobacillus formed and maintained good fermentation quality in whole-plant corn silage.

To investigate the effects of different types of lactic acid bacteria (LAB) on aerobic stability, microbial community and metabolites of whole crop corn silage ensiled with Lentilactobacillus plantarum (LP) and Lentilactobacillus buchneri (LB) or not (CK), the fermentation parameters, aerobic stability, microbial community and metabolite differential components of whole crop corn silage were analyzed after ensiling for 8 months. The results showed that the pH of the whole treatment was lower than 4.2, which indicates good fermentation quality. Compared with the LP group, the LB group significantly improved the aerobic stability of whole crop corn silage (p < 0.05). The addition of LB and LP both increased the number of LAB and the relative abundance of Lentilactobacillus. Metabolite analysis results showed that 28 metabolites were significantly different between the LP and CK groups (p < 0.01), 15 metabolites were significantly different between the LB and CK groups (p < 0.01), and 17 metabolites were significantly different between the LP and LB groups (p < 0.01). The antioxidant metabolites 9-oxo-10(E), 12(E)-octadecadienoic acid and 9(Z),11(E),13(E)-octadecatrienoic acid ethyl ester in the LB group were significantly higher than those in the lp group (p < 0.01). Therefore, compared with LP, obligate heterofermentative LB is more beneficial to maintain the stability of whole crop corn silage after cellar opening.