Data/hora: 20/06/2024 17:19:09

Biblioteca(s): | Embrapa Soja.
Data corrente: | 23/11/2000
Data da última atualização: | 09/03/2006
Autoria: | PRANDO, H. F.; SOSA-GOMEZ, D.R.; ROSADO NETO, G. H.
Título: | Control aspects of oryzophagus oryzae with beauveria bassiana, metarhizium anisopliae and fipronil in water-seeded rice.
Ano de publicação: | 2000
Fonte/Imprenta: | In: INTERNATIONAL CONGRESS OF ENTOMOLOGY, 21., 2000, Foz do Iguassu. Abstracts... Londrina: Embrapa Soja, 2000.
Volume: | v.1
Páginas: | p.536.
Idioma: | Inglês
Conteúdo: | The rice weevil oryzophagus oryzae (Costa Lima) is associated with rice yield losses in Rio Grande do Sul and Santa Catarina states, Brazil. In Rio Grande do Sul, annual losses range from 13.5 million dollars to over 21.0 million dollars. In order to minimize this, rice growers use extremely toxic insecticides with irrigation water. The laboratory tests were concerned with the viability and susceptibility of the entomopathogenic fungi Metarhizium anisopliae (CNPSoMa12) and Beauveria bassiana (Ep01 and CB66) to sunlight and ultra-violet light. The effect of cuticle lipid extracts of O. oryzae and Cosmopolites sordidus Germar on these microorganisms, was investigated. O. oryzae and C. sordidus lipid extracts and hexane and three isolates of entomopathogenic fungi (Ep01, CB66, and Ma12) were used in a 3 x 3 factorial design. The field experiments were conducted in two consecutive years. A total of 13 treatments in four replications and in a completely randomized plots (3 m x 6 m) was used. Rice cultivar, Epagri 108, was water- seeded under 10 cm layer of water. All treatments were hand applied using a watering pot three days after seeding, except where seeds were treated. The viability rate of conidia isolates of M. anisopliae and of B. bassiana was 95%, 89% and 86% for isolates Ma12, Ep01 and CB66, respectively. The isolate CB66 was significantly affected by sunlight after a 4 hour-exposition. The cuticle lipid extract of O. oryzae significantly stimulated germination compared to the cuticle lipid extract of C. sordidus. The isolate Ep01 showed greater germination and growth performance. Field experiments showed that biological and chemical treatments reduced significantly the amount of O. oryzae in treated plots as compared to control treatment. Fipronil treatments caused significantly reduction on the number of larvae, higher plants and lower water content of grains. The use of the entomopathogenic fungi B. bassiana and M. anisopliae to-control O. oryzae is a feasible practice applied in combination with chemicals. Fipronil is efficient to control O. oryzae and can be applied by hand (watering pot) after seeding or by seed treatment methods.
Palavras-Chave: | Brasil; Inseto praga; Pest insects.
Thesagro: | Arroz; Controle Biológico.
Thesaurus Nal: | biological control; Brazil; rice.
Categoria do assunto: | --
Registro original: | Embrapa Soja (CNPSO)
Exemplares: | CNPSO - (18139-1) - UMT - PL - -- - RF 339 -  -  - DIS