Aims: To evaluate the performance of farmers’ onion varieties against purple blotch disease at different locations and to correlate Percent Disease Index with yield attributing and other important traits.
Study Design: Randomized Block Design, Field demonstration.
Place and Duration of Study: National Innovation Foundation- India Gandhinagar Gujarat, Repoli and Palghar research stations of Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli Maharashtra during October 2017 to April 2019.
Methodology: Two farmers’ onion varieties Sona-40 and Sandip were characterized and tested for their response against purple blotch disease under field condition in comparison with location-specific check varieties. Percent Disease Index of purple blotch was observed, compared and correlated with important traits viz. the plant height, leaves per plant, bulb diameter, maturity period, bulb weight, bulb yield and keeping quality. In Maharashtra areas, the study was conducted under Repoli and Palghar conditions during winter (Rabi) 2017, whereas at Gandhinagar Gujarat, it was undertaken in winter (Rabi) 2017 and 2018.
Results: The farmers’ onion cultivars Sandip and Sona-40 were found to be tolerant to the purple blotch disease at all the locations. In Maharashtra and Gujarat, the average Percent Disease Index (PDI) in Sona-40 (12.1%, 12.2%) and Sandip (10.75%, 14.64%) was found significantly lower as compared to the checks respectively. The present studies also confirmed that onion bulb’s yield, weight and keeping quality were significantly correlated with the purple blotch disease.
Conclusion: This study exhibited that the farmers’ onion varieties may perform better against disease infestation such as purple blotch disease. It also confirmed that the response of the onion varieties against purple blotch may vary in different locations. It is shown that the bulb weight, yield and shelf life of bulbs are significantly affected by purple blotch disease.