In vitro screening of different Pseudomonas fluorescens isolates to study lytic enzyme production and growth inhibition
- PDF / 1,046,187 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 49 Downloads / 213 Views
Egyptian Journal of Biological Pest Control
(2020) 30:57
RESEARCH
Open Access
In vitro screening of different Pseudomonas fluorescens isolates to study lytic enzyme production and growth inhibition during antagonism of Fusarium oxysporum f. sp. cumini, wilt causing pathogen of cumin Ridhdhi Rathore1,2, Dinesh N. Vakharia1 and Dheeraj Singh Rathore1,2*
Abstract Land plants exist in close association with bacterial and fungal microbes, where some associations can be pathogenic and others can be mutualistic/beneficial. One such relation exists between host plant, Cuminum cyminum L. (Cumin) and Fusarium oxysporum f. sp. cumini (Foc), the causal pathogen of cumin wilt and Pseudomonas fluorescens (Pf), where Pf acts as a bio-agent for inhibiting Foc and promoting plant growth of cumin. In this study, antagonism by 10 different Pf isolates against Foc was studied under laboratory conditions through percent growth inhibition and biochemical mechanisms. Among these Pf isolates, Pf-5 exhibited the highest in vitro growth inhibition (82.51%). A positive correlation was observed between percent growth inhibition and specific activities of hydrolytic enzymes, chitinase, β-1, 3 glucanase, and protease, where a negative correlation was observed with cell wall degrading enzymes, cellulase and polygalacturonase. To conclude, isolate Pf-5 could be a potential biocontrol agent for Fusarium wilt disease of cumin. Keywords: Growth inhibition, Cumin wilt, Lytic enzymes, Microbe-microbe interaction, Pseudomonas, Fusarium
Background Cumin (Cuminum cyminum L.) is widely grown as an important spice crop in arid and semi-arid regions of the Indian subcontinent. India is the world’s largest producer, consumer, and exporter of cumin (Bhatnagar et al., 2013). The fungal disease wilt, caused by the soil-borne phytopathogens, Fusarium oxysporum f. sp. cumini (Foc), is one of the major threats to cumin production in India and worldwide (Özer and Bayraktar, 2015). For proper management of Fusarium wilt, an integrated approach combining cultural, biological, and * Correspondence: [email protected] 1 Department of Biochemistry, College of Agriculture, Junagadh Agricultural University, Junagadh, India 2 Present address: Crop Science Department, Teagasc, Oak Park, Carlow, Ireland
chemical means is recommended to include the use of resistant cultivars and healthy seeds, adjustment of sowing dates, crop rotation, seed treatment, fungicide application, and biocontrol agents. However, several factors influence the efficacy of these management practices, including pathogenic variability in the fungal populations as well as abiotic factors such as agro-climatic conditions (Lodha and Mawar, 2014). More specifically, management of cumin wilt disease is difficult due to limited resistance against wilt in existing germplasm throughout the world (Lodha and Mawar, 2014). Due to the soilborne nature of Fusarium, the cultural practice of crop rotation restricts cumin cultivation for long periods as fungal spores can survive in soil for up to 6 years
Data Loading...
