| Summary: | To develop a silage fermentation technique to adapt to global climate changes, the microbiome and fermentation dynamics of corn silage inoculated with heat-resistant lactic acid bacteria (LAB) under high-temperature conditions were studied. Corn was ensiled in laboratory silo, with and without two selected strains, <i>Lactobacillus salivarius</i> LS358 and <i>L. rhamnosus</i> LR753, two type strains <i>L. salivarius</i> ATCC 11741<sup>T</sup> and <i>L. rhamnosus</i> ATCC 7469<sup>T</sup>. The ensiling temperatures were designed at 30 °C and 45 °C, and the sampling took place after 0, 3, 7, 14, and 60 days of fermentation. The higher pH and dry matter losses were observed in the silages stored at 45 °C compared to those stored at 30 °C. Silages inoculated with strains LS358 and LR753 at 30 °C had a lower ratio of lactic acid/acetic acid. The dominant bacterial genera gradually changed from <i>Pediococcus</i> and <i>Lactobacillus</i> to <i>Lactobacillus</i> in silages during ensiling at 30 °C, while the bacterial community became more complex and fragmented after 7 d of ensiling at 45 °C. The high temperatures significantly led to a transformation of the LAB population from homo-fermentation to hetero-fermentation. This study is the first to describe microbial population dynamics response to high temperature during corn ensiling, and the results indicate that <i>L. rhamnosus</i> 753 shows potential ability to improve silage fermentation in tropics and subtropics.
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