Efeitos da introdução dos genes opaco-2 e farináceo-2 na variedade de milho centralmex
Palavras-chave:
genes opaco-2, milho normal, peso sementes, proteína lisina, densidade sementesResumo
The genes opaque-2 and floury-2 were independently incorpo- rated into the corn variety Centralmex, and their effects on S0-kernel weight, kernel density and protein and lysine content were noted. Both opaque-2 and floury-2 kernels weighed approximately 12% less than normal kernels, and both were less dense than normal kernels with opaque-2 kernels having the lowest density. There was enough variability in both characteristics, however, to suggest that both kernel weight and density could be improved in the opaque-2 and floury-2 through selection. On a dry weight basis there was no significant difference in protein content between kernel types. Opaque-Z kernels, however, had 100 and 25% more lysine than normal and floury-2 kernels respectively. On a percent protein basis opaque-2 also had the highest and normal kernels the lowest lysine levels.
Referências
ALEXANDER,D.E. - Problems associated with breeding opaque- 2 corns, and some proposed solutions. In: Proceedings of the High lysine Corn Conference. Washington, U.S.A. Corn Refiners Association, Inc. 1966. p. 143-147.
ALEXANDER, D.E., LAMBERT, R.J. e DUDLEY, J.W. Breeding problems and potentials of modified protein maize. In: New Approaches to Breeding for Improved Plant Protein Viena, Austria. International Atomic Energy Agency,1969 p. 55-65.
ALVEY, D.D.e HAMILTON, J.R. - Effect of genetic background on the lysine content of corn endosperm homozygous for opaque-2’ gene. Agronomy Abstracts, U.S.A., p. 3. 1966.
BARBOSA, H.M. - Genes and gene combinations associated with protein, lysine,and carbohidrate content in the endosperm of maize (Zea mays, L.) U.S.A., Purdue University, 1971. 115 p. (Tese de Ph.D.).
MERTZ, E.T., BATES, L.S. e NELSON, O.E. Mutant gene that changes protein composition and increases lysine content of maize endosperm. Science, U.S.A. 145:279-280. 1964.
NACIF, A.P. Efeito da introdução dos genes opaco-2 e farináceo-2 sobre características físicas e químicas de milhos tropicais. Viçosa, Universidade Federal de Viçosa, 1972. 53 p. (Tese de M.S.).
NELSON, O.E. - O programa de milho opaco-2 na Universidade de Purdue. In: Anais de VII Reunião Brasileira do Milho e I Simpósio sobre o Milho Opaco. Universidade Federal de Viçosa, M.G., Imprensa Universitária. 1971. p.160-183.
NELSON, O.E. - Problemas especiais do melhoramento para qualidade nutritiva. In: Anais da VII Reunião Brasileira do Milho e I Simpósio sobre o Milho Opaco. Universidade Federal de Viçosa, M.G., Imprensa Universitária. 1971.p. 301-324.
NELSON, 0.E., MERTZ, E.T. e BATES, L.S. - Second mutant gene affecting the amino-acid pattern of maize endosperm proteins. Science. U.S.A. 150: 1469-1470. 1965.
NEUFFER, M.G., JONES, L. e ZUBER, M.S. - The Mutants of Maize. Wisconsin, U.S.A., Crop Science Society of America, 1968. 74p.
PAEZ, A.V. - Combining ability analysis of kernel compoments in high lysine corn. Agronomy Abstracts, U.S.A. p. 26. 1970.
SARAIVA, L.S. Relação entre peso relativo de sementes e diversas características químicas e físicas no milho opaco-2. Viçosa, Universidade Federal de Viçosa, 1971. 49 p. (Tese de M.S.).
SREERAMULU, C. e BAUMAN, L.F. Yield components and protein quality of opaque-2 and normal diallels of maize. Crop Science, U.S.A. 10:262-265. 1970.
SREERAMULU, C., BAUMAN, L.F. e GARY ROTH. Effect of outcrossing on protein quality, kernel weight, and related characters in opaque-2 and floury-2 maize (Zea mays, L.). Crop Science, U.S.A. 10:235-236. 1970.
