Data/hora: 13/06/2024 04:52:30

Provedor de dados: 	52	
País: 	Brazil	
Título: 	Optical and ultrastructural study of the pollen grain development in hermaphrodite papaya tree (Carica papaya L.)	
Autores: 	Santos,Lídia Márcia Silva; Pereira,Telma Nair Santana; Souza,Margarete Magalhães de; Damasceno Junior,Pedro Correa; Costa,Fabiane Rabelo da; Ribeiro,Beatriz Ferreira; Freitas,Noil Gomes de; Pereira,Messias Gonzaga.	
Data: 	2008-06-01	
Ano: 	2008	
Palavras-chave: 	Carica papaya; Microsporogenesis; Microgametogenesis; Pollen grain; Ultrastructure.	
Resumo: 	The objective of this study was to describe the pollen grain development in hermaphrodite papaya tree. The flower buds were collected at different stages of the development and the anthers were treated chemically for observation under optical and electronic transmission microscopes. The pollen grain development followed the normal pattern described for the Angiosperms. The pollen grain development was described from meiocyte to the mature pollen grain. In the microsporogenesis, the microspore mother cells or the meiocytes underwent meiosis giving rise to the tetrads that were enclosed by the calose. Later, the tetrads were released by the dissolution of the calose by calase activity and microspores underwent mitosis. Microgametogenesis was characterized by asymmetrical mitotic division of each microspore giving rise to bi-nucleate pollen grains. The structures similar to the plastids were found in the cytoplasm and close to the nucleus of the generative cell. Gradual degeneration was observed in the tapetum during the male gamete development.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000300013	
Editor: 	Instituto de Tecnologia do Paraná - Tecpar	
Relação: 	10.1590/S1516-89132008000300013	
Formato: 	text/html	
Fonte: 	Brazilian Archives of Biology and Technology  v.51 n.3 2008	
Fonte: 	info:eu-repo/semantics/openAccess