Data/hora: 05/06/2024 16:59:59

Biblioteca(s): 	Embrapa Arroz e Feijão; Embrapa Unidades Centrais.	
Data corrente: 	04/01/2001	
Data da última atualização: 	07/04/2022	
Autoria: 	PINHEIRO, B. da S.; AUSTIN, R. B.; CARMO, M. P. do; HALL, M. A.	
Afiliação: 	BEATRIZ DA SILVEIRA PINHEIRO, CNPAF; ROGER BRIAN AUSTIN; MARIA PEREIRA DO CARMO; MICHAEL ALAN HALL.	
Título: 	Carbon isotope discrimination and yield of upland rice as affected by drought at flowering.	
Ano de publicação: 	2000	
Fonte/Imprenta: 	Pesquisa Agropecuária Brasileira, v. 35, n. 10, p. 1939-1947, out. 2000.	
ISSN: 	0100-204X	
DOI: 	https://doi.org/10.1590/S0100-204X2000001000004	
Idioma: 	Inglês	
Conteúdo: 	Field experiments involving upland rice genotypes, sown in various dates in late season, were carried out to assess the relationship of carbon isotope discrimination with grain yield and drought resistance. In each one of the three years, one trial was kept under good water availability, while other suffered water shortage for a period of 18-23 days, encompassing panicle emergence and flowering. Drought stress reduced carbon isotope discrimination measured on soluble sugars (Ds) extracted from stem uppermost internode at the end of the imposition period, but had relatively less effect on bulk dry matter of leaves, sampled at the same period, or that of uppermost internodes and grains, sampled at harvest. The drought-induced reduction in Ds was accompanied of reduced spikelet fertility and grain yield. In the three trials subjected to drought, genotypes with the highest yield and spikelet fertility had the lowest Ds. However, this relationship was weak and it was concluded that Ds is not a sufficiently reliable indicator of rice drought resistance to be useful as a screening test in breeding programs. On the other hand, grain yield and spikelet fertility of genotypes which were the soonest to reach 50% flowering within the drought imposition period, were the least adversely affected by drought. Then, timing of drought in relation to panicle emergence and to flowering appeared to be a more important cause of yield variation among genotypes than variation in Ds.	
Palavras-Chave: 	Fertilidade da espigueta; Fertility; Spikelets; Spikelets fertility.	
Thesagro: 	Arroz; Deficiência Hídrica; Entrenós; Espigueta; Fertilidade; Oryza Sativa.	
Thesaurus Nal: 	Internodes; Oryza sativa endornavirus; Rice.	
Categoria do assunto: 	--
F Plantas e Produtos de Origem Vegetal	
URL: 	http://ainfo.cnptia.embrapa.br/digital/bitstream/AI-SEDE/18813/1/pab20_056.pdf	
Registro original: 	Embrapa Arroz e Feijão (CNPAF)	
Exemplares: 	AI-SEDE - (18813-1) - UPE - AP - PP - 630.72081 - P474 -  - DIS
CNPAF - (17163-1) - UPC - AP - PP - 2000 -  - 2000 - DIS