Effect of bacillus amyloliquefaciens on plant growth and suppression of bipolaris leaf blight in Wheat

Abstract

Effect of seed priming with a plant growth promoting rhizobacteria (PGPR) strain Bacillus amyloliquefaciens on root-shoot growth and suppression of Bipolaris leaf blight (Bipolaris sorokiniana) in four wheat varieties namely Kanchan, Shatabdi, BARI Gom 27 and BARI Gom-29 was studied. In all varieties seed priming with B. amyloliquefaciens gave significant increase in shoot and root length compared to control. Similarly, a significant increase in fresh and dry shoot and root weight over control was achieved with pre-sowing seed treatment with B. amyloliquefaciens in these wheat varieties. The percent increase in shoot length, root length, fresh shoot weight, fresh root weight, dry shoot weight and dry root weight by B. amyloliquefaciens over control ranged from 25.26 to 34.18%, 34.68 to 42.86%, 19.73 to 36.12%, 27.98 to 49.86%, 44.25 to 70.08% and 47.14 to 77.65%, respectively. The percent increase in root-shoot growth was the highest in cv. Shatabdi which was followed by cv. Kanchan. Seed treatment with the PGPR strain also caused significant reduction in percent Bipolaris leaf blight Disease Index (PDI) compared to control in all wheat varieties. The highest reduction was achieved with B. amyloliquefaciens in all four varieties. The percent reduction in PDI by B. amyloliquefaciens over control ranged from 31.83 to 47.59%, respectively. The highest reduction in PDI by B. amyloliquefaciens was observed in cv. Shatabdi. High level of root colonization (14 to 39.13 cfu/g root tissues) was observed by the bacterium in all four varieties. Findings of the study reveal that root colonizing PGPR used for seed priming can promote plant growth and suppress the Bipolaris leaf blight in wheat.