Data/hora: 23/09/2024 15:51:06

Biblioteca(s): 	Embrapa Soja.	
Data corrente: 	26/04/2005	
Data da última atualização: 	27/02/2020	
Autoria: 	LEVY, S. M.; FALLEIROS, A. M. F.; MOSCARDI, F.; GREGÓRIO, E. A.	
Afiliação: 	CNPSO.	
Título: 	The epithelial cell surface along the midgut of susceptible and resistant larvae of Anticarsia gemmatalis (Lepidoptera: Noctuidae) to its nucleopolyhedrovirus.	
Ano de publicação: 	2003	
Fonte/Imprenta: 	In: ANNUAL MEETING SOCIETY FOR INVERTEBRATE PATHOLOGY, 36., 2003, Burlington. Program and abstracts... Burlington, 2003.	
Páginas: 	p. 81.	
Idioma: 	Inglês	
Conteúdo: 	A nucleopolyhedrovirus Anticarsia gemmatalis (AgMNPV) has been widely used as a microbial insecticide in soybean in Brazil. Over 1.6 million hectares have been treated with the AgMNPV in the season 2002/2003. The possibility of selecting field populations of A. gemmatalis resistant to the AgMNPV has been a concern. Although this phenomenon has not been detected in the field yet, a laboratory population of the insect submitted to selection pressure was selected for high resistance to this virus. The insect midgut is considered one of the most effective barriers against viral invasion into the hemocele. Our work aimed to verify if there are differences in the midgut structure, comparing the ultrastructure of the epithelial cell surface of uninfected susceptible (SL) and resistant (RL) A. gemmatalis larvae. The susceptible and resistant strains of A. gemmatalis were reared on artificial diet, under laboratory-controlled conditions at Embrapa, Londrina-PR, Brazil. Fourth instar larvae were used in this study. The midguts of SL, and RL were divided in proximal, medial and distal regions, processed and analyzed under transmission and scanning electron microscopes. The proximal midgut region of SL presented columnar cells with regular microvilli and apical cytoplasmic projections (smooth to irregular). The medial midgut region in SL showed sparse microvilli and large amount of cytoplasmic projections (usualli irregular). The cytoplasmic projections of the distal midgut region in SL were scarce and with membrane disruption. Few microapocrine secretory vesicles were released from the microvilli along the midgut length. The columnar cell surface at the different midgut regions in RL presented an increase in the number of microapocrine secretion as well as in the number of cytoplasmic projections among the microvilli. Many of the cytoplasmic projections exhibited smooth surface with few punctual membrane disruptions. Furthermore, the distal midgut region in RL presented large epithelial infolding with many smooth cytoplasmic projections. Our results show that there are morphological differences in the columnar cell surface along the midgut of SL and RL of A. gemmatalis, which may be related to the insect resistance to AgMNPV infection. This work has been supported by FAPESP and PRONEX (MCT/Finep/CNPq).	
Thesagro: 	Baculovirus; Biologia; Controle Biológico; Praga de Planta; Soja.	
Thesaurus Nal: 	Soybeans.	
Categoria do assunto: 	X Pesquisa, Tecnologia e Engenharia	
Registro original: 	Embrapa Soja (CNPSO)	
Exemplares: 	CNPSO - (24953-1) - UPC - RA - DD -  -  -  - DIS