UPGRADING THE FORMULATION OF Bacillus cereus HSTUB 17 FOR THE MANAGEMENT OF PHOMOPSIS BLIGHT OF BRINJAL

Abstract

Phomopsis blight/fruit rot of brinjal caused by Phomopsis vexans responsible for huge yield loss in Bangladesh. For the sustainable and eco-friendly management of phomosis blight/fruit rot, an upgraded formulation aimed to develop using Bacillus cereus HSTUB 17 with pea bran and different combination of potato starch, tryptone, and yeast extract. In dual culture method, B. cereus HSTUB 17 showed a clear zone of inhibition (54.55 %) against P. vexans. In net house, pea bran with potato starch-based biofungicide followed by spraying of that formulation showed the maximum reduction of phomopsis blight incidence and severity in BARI begun 8 (75.74 % and 78.84 % respectively) and BARI begun 12 (76.733 % and 78.84 % respectively). In both varieties, the same formulated bio-fungicide also revealed the highest plant height (90.33 cm and 90.66 cm, respectively), the highest shoot weight (350 g and 376 g, respectively), the highest root length (28.33 cm and 41 cm, respectively), highest root weight (74 g and 399.67 g, respectively), highest number of leaves/plant (60 and 58.330, respectively) highest number of branch/plants (17 and 13.66, respectively), highest number of flower/plants (5.33 and 4.66, respectively), highest number fruit/plants (12 and 11, respectively), highest yield/plant (2.02 and 3.12 Kg, respectively), highest fruit weight (73 g and 304 g, respectively ), highest fruit length (24 cm and 20 cm, respectively), highest fruit diameter (9.33 cm and 24 cm, respectively), highest amount of chlorophyll-a content (715.3 mg m-2 and 778.7 mg m-2 , respectively), highest amount of chlorophyll-b content (164.47 mg m-2 and 141.4 mg m-2 , respectively ), highest amount of total chlorophyll content (880 mg m-2 and 920.27 mg m-2 , respectively), higher amount of total phenol content (8.894 mg/100 g and 8.0467 mg/100 g, respectively), higher content of total soluble solid (6.433 0Brix and 6.4 0Brix, respectively), higher grade of firmness (2.81 Kg/min and 2.416 Kg/min, respectively), and maximum pH (6.546 and 6.28, respectively ). The survival rate of the formulated bio-fungicide was also studied in different storage conditions for 8 months viz. A: Wooden shelve B: Refrigerated (4 ℃). The shelfs life study for revealed higher amount bacterial population (from 150 to 745 CFU/mL) in pea bran with potato starch-based biofungicide, in wooden shelves condition with pea bran with yeast based biofungicide (from 150 to 1260 CFU/mL). The finding of the research concluded that the possibility of using of formulated B. cereus HSTUB 17 with pea bran combination of potato starch for the sustainable and eco-friendly management of Phomopsis blight of brinjal.