Inoculation of Methylotrophic Bacteria Ameliorate Summer Heat Stress and Enhance the Black Gram (Vigna mungo L.) Growth, Physiology and Antioxidants Properties

Heat stress has a substantial impact on black gram (Vigna mungo L.) by reducing growth, grain yield, and quality. Black gram is highly sensitive to temperature; it requires a range of 27–35 °C for flowering and pod formation. Therefore, to mitigate heat stress during the summer season in black gram, phyllosphere-associated methylotrophic bacteria (Methylobacterium brachiatum (KD1 and SD3), M. thiocyanatum (SD2), and Methylorubrum populi (KD5) were chosen from the previously identified strains. Screening for plant growth-promoting properties revealed that all strains (KD1, KD5, SD2, and SD3) were able to grow on nitrogen-free (N2) medium, produced siderophore (12.57 to 69.10