Comparação de dois métodos de aplicação de fungicidas, irrigação por gotejamento e pulverização convencional no controle do mofo cinzento (Botrytis cinerea Pers.: Fr.) em vasos com plantas de lisianthus (Eustoma grandiflorum (Raf.) Shinn.)

Plan disease control techniques are used through the irrigation water, which reduces the labor and it improves application uniformity with smaller contact of the operator with toxic products, lower environmental impact and lower production cost. In order to control Botrytis cinerea the lisianthus culture, this work aimed to evaluate two fungicide application methods with different treatments. The fungicides were: thiophanate methyl (50 g i.a. L-1), thiophanate methyl + chlorothalonil (50 g i.a. L-1 + 35 g i.a. L-1) and iprodione (50 g i.a. L-1). Number of lesions, number of diseased floral buttons and height of the lisianthus plants were evaluated. It was possible to deduce, that in the growth stage (number of lesions in the plant) as well as in the final stage (number of floral buttons) of the lisianthus culture, the most efficient treatments were 2 (thiophanate methyl + chlorothalonil) and 3 (iprodione). Considering that treatment 2 is a mixture of two fungicides, a systemic and a contact one, independently of application methods, the mixture increased efficiency in relation to treatment 1 (thiophanate methyl). Thus, chemigation was as efficient as spreading technique.

Esporulação de Botryotinia ricini em diferentes meios de cultura

The castor bean plant is a tropical species and is subject to various diseases, which cause great losses. Among these diseases, the gray mold (Botryotinia ricini) is one of the most important. The fungus spore production was evaluated in the media of cultures BDA; Oats-Agar; Mazeina-Agar; Rice-Agar; castor-bean crushed leaves-agar (FM), FM-CaCO3; V8 juice to 5% (V8-5%); V8-10%; V8-20% and tomato juice at 5% (TJ-5%); TJ-10% and TJ-20%. The production of spore in different media of cultures was evaluated at 8(th) days of incubation. The data were analyzed using the comparison of means, through the test Tukey a 5% probability, and the data processed for (X + 1) (0.5). All means of crops tested were able to produce conidia, but the best results was obtained with the culture medium V8-20% (5.7 x 10(6) conidia/mL) and BDA (3.5 x 10(6) conidia/mL).