Effectiveness of fungicide seed treatment in the control of soybean seedling dampingoff caused by Rhizoctonia solani under greenhouse conditions

Abstract

The present study was conducted to evaluate the efficacy of fungicide seed treatment in the control of soybean seedling damping-off caused by Rhizoctonia solani under greenhouse conditions. The experiment was carried out in Dourados, Mato Grosso do Sul State, Brazil. Treated and untreated soybean seeds were sown in previously sterilized sand, contained in plastic trays, in equidistant individual wells at 3cm depth. The soybean sowing density was 200 seeds/plastic tray. Inoculation with R. solani was done by homogeneous distribution of the fungal inoculum onto the substrate surface (5.0g/tray). The fungus was grown for 35 days on autoclaved black oat seeds ground to powder with a mill (1mm). Seedling emergence, pre and post-emergence damping-off, injured seedlings and disease index (severity) were evaluated according to McKinney formula. Fungicide seed treatments had a significant effect (P ≤ 0.05) on seedling emergence, pre and post-emergence damping-off, injured seedlings and disease index (severity). The best results were obtained for fludioxonil+metalaxyl-M+thiabendazole and fipronil+pyraclostrobin+thiophanate-methyl, followed by carbendazim+thiram+pencycuron and thiophanate-methyl+fluazinam. The least efficient treatments were carbendazim+thiram, fludioxonil+metalaxyl-M and carboxin+thiram. Pearson correlation analysis indicated that injured seedlings and disease index were positively correlated (R=0.92). This means that the greater the number of injured seedlings, the greater the disease index and the less efficient the fungicide. The fungicides used in the present study did not have any phytotoxic effect on soybean seedlings.

Factors Influencing the Deterioration of Groundnut Seed Health and Its Implications on Storage Capacity

“…This reinforces the notion that seed rot percentage increases with higher seed moisture content and prolonged storage duration. These findings align with previous research conducted by Hall and Xue [8], Das and Dutta [9], and Goulart et al [10], further validating the observed trends.…”

Viabilidade de sementes de arroz (oryza sativa l.) sob tratamentos de sementes e períodos de armazenamento

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