Genetic Analysis of Sweet Pepper Tolerance to Low Phosphorus Availability in the Soil
Valter R. Oliveira1, Vicente W. D. Casali2, Cosme D. Cruz3, Carlos A. Scapim4 & Nádja M. Pires1
Abstract: The objective of this study was to evaluate the mode of inheritance for sweet pepper (Capsicum annuum L.) tolerance to low P availability in soil, defined here as the ability of plants to produce relatively more biomass (total dry weight) under low P conditions. A complete diallel cross was used involving six previously selected genotypes, three tolerant and three intolerant to low P availability in soil. At 75 days after sowing, total dry weight, shoot and root dry weight, ratio root:shoot dry weight, and total P content in the plant were evaluated. There were no significant reciprocal differences in any of the assessed traits. The results showed that genes controlling tolerance to low P were predominantly but not exclusively dominant. Out of the three tolerant parents, two concentrated dominant genes, and the other, recessive genes for tolerance to low P. The analysis of the genetic components of variation showed that both the additive and the dominant gene effects were involved in the control of all the characteristics, with a greater contribution from the dominance to the genetic variability among parents and F1 hybrids. The estimates of the broadsense heritabilities were high, while the narrow-sense were in general comparatively low. Their magnitudes, however, were at a level that allowed successful selection.
Key words: Capsicum annuum L., breeding, diallel, inheritance
1 Empresa de Pesquisa Agropecuária de Minas Gerais, Centro Tecnológico do Centro-Oeste, Caixa Postal 295, 35701-970, Sete Lagoas-MG, Brasil. E-mail: firstname.lastname@example.org
2 Universidade Federal de Viçosa, Departamento de Fitotecnia, 36571-000, Viçosa-MG, Brasil
3 Universidade Federal de Viçosa, Departamento de Biologia Geral, 36571-000, Viçosa-MG, Brasil
4 Universidade Estadual de Maringá, Departamento de Agronomia, 87020-900, Maringá-PR, Brasil
Andrews, J. 1984. Peppers: the domesticated capsicums. University of Texas Press, Austin. 170 p.
Bailian, L.; McKeand, S.E. and Allen, H.L. 1991. Genetic variation in nitrogen use efficiency of loblolly pine seedlings. Forest Science. 37:613-626.
Braga, J.M. and Defelipo, B.V. 1974. Determinação espectrofotométrica de fósforo em extratos de solos e material vegetal. Revista Ceres. 21:73-85.
Chaubey, C.N.; Senadhira, D. and Gregorio, G.B. 1994. Genetic analysis of tolerance for phosphorus deficiency in rice (Oryza sativa L.). Theoretical and Applied Genetics. 89:313-317.
Clark, R.B. 1990. Physiology of cereals for mineral nutrient uptake, use, and efficiency. p.131-210. In: Baligar, V.C. and Duncan, R.R. (Eds.). Crops as enhances of nutrient use. Academic Press, San Diego.
Coltman, R.R.; Gabelman, W.H.; Gerloff, G.C. and Barta, S. 1987. Genetics and physiology of low-phosphorus tolerance in a family derived from two differentially adapted strains of tomato (Lycopersicon esculentum Mill.). p.309-315. In: Gabelman, W.H. and Loughman, B.C. (Eds.). Genetic Aspects of Plant Mineral Nutrition. Martinus Nijhoff Publishers, Dordrecht.
Cruz, C.D. 1997. Programa Genes. Aplicativo Computacional em Genética e Estatística. Viçosa. Editora UFV. 442 p.
Cruz, C.D. and Regazzi, A.J. 1994. Modelos Biométricos Aplicados ao Melhoramento Genético. Imprensa Universitária, Viçosa. 390 p.
Fawole, I.; Gabelman, W.H.; Gerloff, G.C. and Nordhein, E.V. 1982. Heritability of efficiency in phosphorus utilization in beans (Phaseolus vulgaris L.) grown under phosphorus stress. Journal of the American Society for Horticultural Science. 107:94-97.
Giordano, L.B.; Gabelman, W.H. and Gerloff, G.C. 1982. Inheritance of differences in calcium utilization by tomatoes under lowcalcium stress. Journal of the American Society for Horticultural Science. 107:664-669.
Hayman, B.I. 1954b. The theory and analysis of diallel crosses. Genetics. 39:789-809.
Jinks, J.L. and Hayman, B.I. 1953. The analysis of diallel crosses. Maize Genetics Cooperation Newsletter. 27:48-54.
Singh, R.K. and Chaudhary, B.D. 1979. Biometrical Methods in Quantitative Genetic Analysis. Kalyani Publishers, New Delhi. 304 p.
Steel, R.G.D. and Torrie, J.H. 1980. Principles and Procedures of Statistics. McGraw-Hill Book Company, New York. 633 p.
Tanksley, S.D. 1984. High rates of crosspollination in chile pepper. HortScience. 19:580-582.
Witeaker, G.; Gerloff, G.C.; Gabelman, W.H. and Lindgren, D. 1976. Intraspecific differences in growth of beans at stress levels of phosphorus. Journal of the American Society for Horticultural Science. 101:472-475.