The prevalence and distribution of pathotypes and mating types of Ascochyta rabiei (Pass.) Labr. in India was evaluated during the winter (October to March) seasons of 2017-18 and 2018-19. Forty-fi...
Berseem (Trifolium alexandrinum) is a winter season legume fodder crop widely cultivated in the central and northern parts of India. It is considered the ‘King of fodder’ for its high quality green...
Plant pathogenic fungi and bacteria are a significant threat to global commercial crop production resulting in increased cost of production, reduced crop establishment and productivity. An effort was made to study the antimicrobial activity of silver hydrogen peroxide (SHP) against selected plant pathogenic fungi and bacteria under in vitro conditions. Higher antibacterial activity of SHP was observed against Xanthomonas axonopodis pv. citri (Xac; 39.67 mm), Xanthomonas citri pv. punicae (Xap; 39.00 mm), and Ralstonia solanacearum (Rs; 36.67 mm) at 500 ppm concentration. SHP was superior to streptocycline (500 ppm) against Xac (25.33 mm) and Xcp (22.67 mm) at 100 ppm. The soil-borne fungi viz., Pythium aphanidermatum and Fusarium solani failed to initiate mycelium growth on PDA at the concentration of 5000 ppm and above. The average size of SHP particles was 462 nm in diameter, and 73.40% of particles had the size of 378 nm, which reflects the particles present in SHP solution in the form of colloids. The effective doses (100–5000 ppm) did not show any phytotoxicity symptoms in plants, while leaf necrosis was noticed at 10,000 ppm after four days of application. SHP (≤5000 ppm) can be used to effectively manage both fungal and bacterial plant pathogens by a single application. Further field studies need to be conducted for validation and commercial use of SHP.
7 November 2021 in Archives of Phytopathology and Plant Protection
Berseem (Trifolium alexandrinum L.) is one of the important legume fodder crops. It is widely grown in Central and Northern parts of India during winter season. Disease symptoms resembling to collar rot was observed in the breeder seed production and research fields of berseem at ICAR-IGFRI, Jhansi, Uttar Pradesh, India in March 2019 and April 2020. Disease incidence was ranged from 15–20% and 20-25% in 2019 and 2020, respectively. Disease symptom appeared as water soaked lesions on surface of collar region followed by the development of rotten areas with white mycelial mass and finally plants were dried. The associated pathogen was isolated and identified as Sclerotium rolfsii (Teleomorph: Athelia rolfsii) on the basis of morphological characters and sequence analysis of ITS, LSU and SSU regions of rDNA. Artificial inoculation of pathogen revealed cent per cent disease incidence and wilting of plants. To best of our knowledge, this is first complete report on etiology of collar rot disease caused by Sclerotium rolfsii on berseem in India.