Resumo
We aimed to isolate and identify yeasts found in the tomato fruit in order to obtain isolates with biotechnological potential, such as in control of fungal diseases that damage postharvest fruits. We identified Candida orthopsilosis strains LT18 and LT24. This is the first report of this yeast on Lycopersicum esculentum fruits in Brazil.
Assuntos
Candida parapsilosis , Solanum lycopersicum/microbiologia , MicosesResumo
We aimed to isolate and identify yeasts found in the tomato fruit in order to obtain isolates with biotechnological potential, such as in control of fungal diseases that damage postharvest fruits. We identified Candida orthopsilosis strains LT18 and LT24. This is the first report of this yeast on Lycopersicum esculentum fruits in Brazil.(AU)
Assuntos
Solanum lycopersicum/microbiologia , Candida parapsilosis , MicosesResumo
ABSTRACT The coffee root mealybug Dysmicoccus texensis (Tinsley) attacks the roots of this plant and can cause serious damage to crops, and consequent losses in production. The entomopathogenic nematodes (EPNs) are effective agents in controlling pests found in soil, which suggests a likely effectiveness in controlling the coffee root mealybug. Therefore, this study aimed to evaluate the pathogenicity of some strains of EPNs against the coffee root mealybug through selection tests of isolates, determination of the maximum lethal concentration (LC99) and the pathogenicity of crypts collected in the field. The isolated Heterorhabditis sp. CCA, Heterorhabditis bacteriophora, Heterorhabditis sp. JPM3.1 and Heterorhabditis sp. JPM3 presented higher virulence, reaching maximum mortality values of 100, 94, 94 and 82% respectively at the highest concentration that was tested (100 infective juveniles IJ/insect). The LC99 determined for Heterorhabditis sp. CCA was estimated at 530 IJ/plate. A similar value was found for Heterorhabditis sp. JPM3, which had the LC99 equal to 560 IJ/plate. Estimating the concentration by area, the value obtained for Heterorhabditis sp. CCA and Heterorhabditis sp. JPM3 was 28 and 29 IJ/cm2, respectively. In the test conducted with crypts, both isolated from EPNs were pathogenic to insects.
RESUMO A cochonilha-da-raiz-do-cafeeiro Dysmicoccus texensis (Tinsley) ataca as raízes desta planta, podendo causar sérios danos às plantações e conseqüentes perdas na produção. Os nematóides entomopatogênicos (NEPs) são agentes eficientes no controle de várias pragas encontradas no solo, o que sugere provável eficiência no controle da cochonilha-da-raiz-do-cafeeiro. Dessa forma, este trabalho teve por objetivo avaliar a patogenicidade de alguns isolados de NEPs à cochonilhada-raíz-do-cafeeiro através de testes de seleção de isolados, determinação da concentração letal máxima (CLM99) e patogenicidade a criptas coletadas no campo. Os isolados Heterorhabditis sp. CCA, Heterorhabditis bacteriophora, Heterorhabditis sp. JPM3.1 e Heterorhabditis sp. JPM3 foram os que apresentaram maior virulência, alcançando valores máximos de mortalidade de 100, 94, 94 e 82%, respectivamente, na maior concentração testada (100 juvenis infectantes (JI)/inseto). A CL99 determinada para Heterorhabditis sp. CCA foi estimada em 530 JI/placa. Valor semelhante foi encontrado para Heterorhabditis sp. JPM3 que teve a CL99 igual a 560 JI/placa. Estimando a concentração por área, o valor obtido para Heterorhabditis sp. CCA e Heterorhabditis sp. JPM3 foi de 28 e 29 JI/cm2, respectivamente. No teste realizado com criptas, ambos os isolados de NEPs foram patogênicos aos insetos.