On-line version ISSN 1678-4596
ISHIKAWA, Mayra Suemy; FONSECA, Inês Cristina de Batista and IGARASHI, Seiji. Chemical treatment in seeds on the development of the spot blotch in wheat plants. Cienc. Rural [online]. 2012, vol.42, n.8, pp.1341-1346. ISSN 1678-4596. http://dx.doi.org/10.1590/S0103-84782012000800002.
The objective of this research was to evaluate the effect of fungicides difenoconazole and carboxin + thiram applied in seed wheat cultivars 'CD 104' and 'OR Mirante', inoculated with Cochliobolus sativus. The experimental design was completely randomized in a 2x3 factorial design (2 cultivars and 2 fungicides + untreated control) in seven replications. The fungi was isolated and reproduced in PDA culture medium (potato-dextrose-agar) and subsequently multiplied in seeds of wheat pre-cooked and is the source of inoculum. The evaluations were the number of lesions in the basal leaf of five plants per pot at 22, 25, 29, 31, 35 and 38 days after sowing (DAS), and at 41DAS were evaluated the length (cm), fresh weight (g) and dry weight (g) of shoot and root. From the evaluations of the number of lesions was also calculated the area under the disease progress curve (AUDPC). The datas were subjected to analysis of variance and means were compared by Tukey test at 5% probability. The 'CD 104' cultivar was more susceptible to the pathogen than 'OR Mirante'; difenoconazole was efficient to control the disease as carboxin + thiram equaled the witness; both fungicides interfered negatively on plant development, since the average length, fresh weight and dry shoot and root obtained from treated seed is lower than the untreated seeds.
Keywords : Triticum aestivum; Bipolaris sorokiniana; difenoconazole; carboxin + thiram.