DEVELOPMENT OF FORMULATED Serratia marcescens HSTUB 8 FOR THE ECO-FRIENDLY 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 phomopsis blight/fruit rot, a formulated bio-fungicide was intended to develop using previously isolated and identified S. marcescens HSTUB 8 and charcoal, maize bran, wood dust, soybean bran and pea bran at field conditions. The survival rate of the formulated bio-fungicides were also evaluated in different storage conditions viz., A: refrigerated (40 C), B: wooden shelve. In a dual culture approach, S. marcescens HSTUB 8 showed a clear zone of inhibition (28.57%) against P. vexans. In field conditions, wood dust-based formulated S. marcescens HSTUB 8 followed by spraying of S. marcescens HSTUB 8 suspension resulted the maximum reduction of phomopsis blight incidence (%) and severity (%) in BARI begun 9 (48.05% and 72.85%, respectively) and BARI begun 10 (48.39% and 69.89 %, respectively). In both varieties, the same formulated bio-fungicide also revealed the highest plant height (66 and 69.67 cm, respectively), the highest shoot weight (295 and 253 g, respectively), the higher root length (27 and 41 cm, respectively), higher root weight (34.73 and 27.27g, respectively), maximum number of branch/plant (14 and 10, respectively), minimum days for first flowering (71 and 73 DAT, respectively), the highest number of fruit per plant (16 and 21), the highest yield per plant (3.24 and 1.79 Kg/plant), maximum fruit weight (202.43 and 83.85 g/fruit), highest fruit length (12.83 and 33 cm), maximum fruit diameter (24 and 11.67 cm), higher accumulation of total phenol content (7.25 and 8.91 mg/100g), higher content of total soluble solids (5.39 and 4.96 °Brix), higher grade of firmness (3.81 and 2.40 Kg/min), and maximum pH (5.26 and 5.27 respectively). The shelf life study revealed higher number of bacterial population in wood dust-based bio-fungicide (from 225 to 790) at 90 days after storage in refrigerated conditions. In case of wooden shelve, the highest population (from 225 to 460) was found in pea bran-based bio-fungicide. The findings of the study revealed the possibility of the using of formulated S. marcescens HSTUB 8 with wood dust-based, formulation for the sustainable and eco-friendly management of phomopsis blight of brinjal at field conditions.