Biocontrol Potentials of Plant Growth Promoting Rhizobacteria against Fusarium Wilt Disease of Cucurbit

Abstract

Fusarium spp., are the major soil-borne as well as seed borne pathogens causing wilt and rot diseases in more than 80 plant species including cucurbits. Fusarium spp., causes up to 100 % yield loss in the worldwide. Eleven isolates including three standard isolates were tested both in-vitro and in-vivo. In-vitro assay was done by dual culture method. Maximum inhibition was in case of Fusarium solani by Bacillus cereus MIC5. Sarratia spp. MIC1 antagonized the F. verticillodes and F. solani2. P. aeruginosa MIC2 inhibits all tested isolates F. oxysporum1. P. aeruginosa MTCC2581 suppressed the radial growth rate of F. oxysporum2. The two systemic fungicides used were chlorothalonil + mefenoxam (1000 ppm) and carbendazim (75 ppm to 500 ppm) which checked the growth of F. oxysporum. Carbendazim was more effective compared to mefenoxam + chlorothalonil at all tested concentrations. The crude extract of P. aeruginosa MIC2 developed in chloroform: methanol (9:1) showed a metabolite at Rf - 0.77 which it may be 2,4- diacetylphloroglucinol (DAPG), a broad-spectrum antimicrobial agent. Increased cucurbit seeds germination and seedling vigour was observed in B. amyloliquefaciens MIC6 (68% 1576) and P. aeruginosa MTCC2581 (70% 1929) in primed seeds. Further P. aeruginosa MTCC2581 can be tested in the field against the Fusarium wilt.

Potential Role of Rice Plant Growth Promoting Phylloplane and Rhizospheric Bacteria in Controlling Xanthomonas oryzae pv. oryzae

“…Even though, Pseudomonas spp. are indigenous and involve in various rhizomicrobiomes but few of them have the ability to grow above 37°C and become opportunistic pathogens, thuspredictable biosafety regulations are needed to implement this technology practically for field application [95]. In a nutshell, based on all results achieved from during this study, bacterial strains may be an effective bio-inoculant for controlling BB of rice by ensuring its biosafety aspects.…”

Identification of plant growth promoting antagonistic bacteria against blast disease of rice

“…It has also been documented that the application rates of phosphate fertilizers reduced to 50% by inoculating phosphate solubilizing microbes (PSM) in crops without significantly reducing crop yield (Yazdani et al, 2009). In sustainable agriculture, certain plant pathogens can be controlled by biological agents like plant growth promoting bacteria (PGPB) and PGPB can also be used as biofertilizer (Shanthi and Vittal, 2013). There are a lot of PGPB strains that reported to suppress numerous of plant pathogen, reduce the disease incidence, stimulate the plant growth factor and supplies the nutrition for the growth of the plant (Hariprasad et al, 2009;Yasmin et al, 2017).…”

Screening of Bacteria as Antagonist against Xanthomonas oryzae pv. oryzae, the Causal Agent of Bacterial Leaf Blight of Paddy and as Plant Growth Promoter

“…In sustainable agriculture, certain plant pathogens can be controlled by biological agents like plant growth promoting bacteria (PGPB) and at the same time, PGPB was used as bio-fertilizer [23]. There are a lot of PGPB strains that reported to suppress numerous of plant pathogen, reduce the disease incidence, stimulate the plant growth factor and supplies the nutrition for the growth of plant [23][24][25][26]. Therefore, it has been considerable research interest in the potential use of antagonistic bacteria as PGPB [27,28].…”