Data/hora: 03/06/2024 14:08:23

Biblioteca(s): 	Embrapa Arroz e Feijão; Embrapa Cerrados; Embrapa Trigo.	
Data corrente: 	26/04/1993	
Data da última atualização: 	20/07/2010	
Autoria: 	SALINAS, J. G.	
Título: 	Differential response of some cereal and bean cultivars to Al and P stress in an oxisol of Central Brazil.	
Ano de publicação: 	1978	
Fonte/Imprenta: 	Raleigh: North Carolina State University, 1978.	
Páginas: 	326 p.	
Idioma: 	Inglês
Português	
Notas: 	Tese Doutorado.	
Conteúdo: 	A series of eight greenhouse experiments and six field experiments were conducted at the Cerrado Research Center near Brasilia, Brazil, with the purpose of identifying varietal tolerances to Al toxicity and/or low available of P in five important crops (wheat, corn, sorghum, upland rice and beans) as part of a low input strategy to manage savanna Oxisols. A flowing culture solution technique was developed to screen varieties for Al, P, and Al+P stresses in the greenhouse. Stress levels were maintained by adjusting pH, Al and P concentration every 2 days. The main parameters measured were top and root growth rates, root elongation rates, specific absorption and translocation rates of P, Ca, Mg and Al, and percentage translocation of these nutrients to the tops. Most cultivars were tested for Al and/or P stress under field conditions in an Oxisol. Two sorghum hybrids were also field tested more intensively for Al tolerance at several lime rates. The existence of differential tolerance to Al toxicity and/or low available P in culture solutions and field conditions was established among varieties of the crops. With the exception of corn, tolerant varieties to Al stress were also tolerant to P stress, and those sensitive to one factor were also sensitive to the other. In the absence of stress conditions, the variability in growth and nutrition was less marked among species and varieties within species. Brazilian wheat varieties were more tolerant to Al and/or P stress than the Mexican varieties. This was related to the soil properties of locations where they were bred. Inbred corn lines did not exhibit parallel tolerance to the two factors. Breeding appears necessary to obtain tolerance to Al+ P stress. Among the corn hybrids and varieties Cargill-111 was most tolerant to P stress and to Al + P stress, but less marked differences under Al stress condition were observed among these genotypes. The sorghum hybrid, Taylor Evans y-101, was the most tolerant to the mentioned stress factors. When tested together with RS-610, the Al tolerance of Taylor Evans y-101 was associated with better root proliferation than RS 610 which permitted a more effective use of subsoil water. Pratão Precoce, followed by IAC-1246 and IAC-47 were the most tolerant rice varieties while Flotante and Batatais were the least tolerant. Finally, Carioca-1030, Ricopardo-896 and Costa Rica-1031 were the most tolerant bean varieties to Al+P stress. Sensitive parameters to measure differential Al tolerance were root RGR and RER of roots. With certain exceptions, top RGR and root RER were the most sensitive parameters under P stress, while under Al + P stresses both top and root growth rates were important. Species and varieties tolerant to Al stress and/or P stress maintained a more favorable P, Ca and Mg absorption and translocation rates than sensitive varieties. Effect of Al stress on Ca and Mg uptake was to decrease the specific absorption and translocation rates but generally not the percentage translocation. Most of the Al was retained in the roots with a small percent transported to the tops. Under both greenhouse and field conditions the ranking of varieties was similar. Consequently, screening in culture solutions for 10 days predicts ranking of varieties in the field in terms of grainin yields. The advantage of the greenhouse tests is to reduce time and space requirements. This study show the potential for utilizing tolerant cultivars as an important component of managing savanna Oxisols.	
Palavras-Chave: 	Aluminium; Arroz de terras altas; Bean; Brasil; Maize; Regiao Central; Sorghum; Tolerância; Upland rice; Wheats.	
Thesagro: 	Alumínio; Arroz; Cerrado; Deficiência; Feijão; Fósforo; Milho; Oryza Sativa; Oxisol; Phaseolus Vulgaris; Sorgo; Trigo; Triticum Aestivum; Zea Mays.	
Thesaurus Nal: 	beans; Brazil; Ferralsols; phosphorus.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Arroz e Feijão (CNPAF)	
Exemplares: 	CNPAF - (1731-1) - ADD - TS - -- - T 037/78 - SAL - 1978.00037 - DIS
CPAC - (5438-1) - ADD - TS - -- - CRI2343 -  - CRI2343 - DIS
CPAC - (16664-1) - ADD - TS - -- - T038 -  - T038 - DIS
CPAC - (16665-1) - ADD - TS - -- - T038/78 - SAL - T038/78 - DIS
CNPT - (29950-1) - ADD - TS - -- - TS-0370 -  - 0370 - DIS