Filtration enrichment method for isolation of auxotrophic mutants of Trichoderma harzianum rifai

A obtenção de marcas genéticas, quer sejam para resistência a drogas, quer para auxotrofia, é uma etapa trabalhosa mas importante em pesquisa genética. Esse trabalho visou a obtenção de mutantes auxotróficos de Trichoderma harzianum utilizando-se a técnica de enriquecimento por filtração. A técnica mostrou-se superior à técnica convencional de isolamento total. Doze mutantes auxotróficos obtidos foram testados quanto a estabilidade, crescimento e resistência ao fungicida benomil. Eles apresentaram taxas de crescimento e esporulação comparáveis à linhagem parental e dois mutantes foram resistentes a benomil em uma concentração de 500µg/ml.

Production of yacon plantlet (Polymnia sonchifolia poep. et endl.) in different organic fertilization

The work was carried out in nursery of the Agronomical Science College (ASC) UNESP-Botucatu, in period from September 21(st) to October 31(st) 2000. The propagation material (rhizophores) was obtained from plants, which were cultivated in the area of ASC. The rhizophores were selected according to their vigor and size. Healthy rhizophores were chosen between 15 and 25 g, which were treated with benomil (0,6%, 10 minutes). As a basic commercial substratum Solomix((R)) was used with mixing cattle manure and chicken manure in the following proportions: T1- pure substratum; T2 - substratum + cattle manure (1:1), T3- substratum + cattle manure (2:1); T4- substratum + chicken manure (4:1). The yacon rhizophores presented good shoots in all substrata with exception of T4. For all parameters no significant difference between the pure commercial substratum and its mixture with cattle manure were observed; however, the addition the chicken manure in the studied proportions revealed harmful effect on the survival and development of the plantlets. The results indicated, that the viability of smaller size rhizophores was higher as the size conventionally used in Brazil (60 to 80 g).

Controle de fungos contaminantes no cultivo do cogumelo comestível shiitake (Lentinula edodes) em toros de eucalipto (Eucalyptus urophylla)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Doenças do pimentão em regiões produtoras do Equador: identificação e manejo da pata seca e ocorrência de viroses

Pós-graduação em Agronomia (Proteção de Plantas) - FCA