Abstract
The genetical control of F1 heterosis, observed in a cross of desirable Nicotiana tabacum varieties, was investigated by analysing the data of the basic generations, triple test cross-families and random samples of doubled haploids (DH) and single-seed descent (SSD) lines. Analyses of the first-degree statistics revealed a complex control underlying the genetic variation, including the presence of epistasis, linkage, maternal effects and their interactions, in addition to the additive and dominance effects of the genes segregating in the cross. These analyses identified gene dispersion, directional dominance, and duplicate epistasis, as the main causes of heterosis. The triple test-cross analysis also confirmed the presence of non-allelic interactions and indicated that the dominance ratio, although inflated by epistasis, is consistently partial for all the traits. The extent of transgression in the recombinant inbred lines finally established unequivocally that, as in numerous other crosses, gene dispersion and unidirectional, but partial, dominance are the true causes of heterosis in this cross too.
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Chowdhury MKU (1984) Dihaploids of Nicotiana tabacum and Nicotiana rustica. PhD thesis, The University of Birmingham
Coombs DT (1980) Biometrical genetics of tobacco. PhD thesis, The University of Birmingham
Jinks JL (1983) Biometrical genetics of heterosis. In: Frankel R (ed) Heterosis. Monographs on theoretical and applied genetics. Springer-Verlag, Berlin, pp 1–46
Jinks JL, Perkins JM (1970) A general method of detecting additive, dominance and epistatic components of variation. III. F2 and backcross populations. Heredity 25:419–429
Jinks JL, Pooni HS (1976) Predicting the properties of recombinant inbred lines derived by single seed descent. Heredity 36:253–266
Jinks JL, Pooni HS (1980) Comparing predictions of mean performance and environmental sensitivity of recombinant inbred lines based upon F3 and triple test-cross families. Heredity 45:305–312
Jinks JL, Chowdhury MKU, Pooni HS (1985a) Comparison of the inbred lines derived from a hybrid of tobacco (burley x flue cured) by dihaploidy and single-seed descent. Heredity 55:127–133
Jinks JL, Pooni HS and Chowdhury MKU (1985b) Detection of linkage and pleiotropy between characters of Nicotiana tabacum using inbred lines produced by dihaploidy and single-seed descent. Heredity 55:327–333
Kearsey MJ, Jinks JL (1968) A general method of detecting additive, dominance and epistatic variation for metrical traits. I. Theory. Heredity 23:403–409
Mather K, Jinks JL (1982) Biometrical genetics (3rd edn.). Chapman and Hall, London
Pooni HS (1993) Genetics of heterosis and its implications for crop improvement. Annal Biol 9:323–332
Pooni HS, Jinks JL (1978) Predicting the properties of recombinant inbred lines derived by single-seed descent for two or more characters simultaneously. Heredity 40:349–361
Pooni HS, Jinks JL (1981) Sources of predictions and their reliability in predicting the properties of recombinant inbred lines which can be obtained from a cross by single-seed descent. IVth Int Barley Genet Symp, Edinburgh University Press, Edinburgh, Scotland, pp 73–78
Pooni HS, Treharne AJ (1994) The role of epistasis and background genotype in the expression of heterosis. Heredity 72:628–635
Pooni HS, Jinks JL, Jayasekara NEM (1978) An investigation of gene action and genotype x environment interaction in two crosses of Nicotiana rustica by triple test-cross and inbred-line analysis. Heredity 41:83–92
Pooni HS, Coombs DT, Virk PS, Jinks JL (1987) Detection of epistasis and linkage of interacting genes in the presence of reciprocal differences. Heredity 58:257–266
Tapsell CR, Thomas WTB (1983) Cross prediction studies on spring barley. 2. Estimation of genetical and environmental control of yield and its component characters. Theor Appl Genet 64:353–358
Thomas WTB, Tapsell CR (1983) Cross prediction studies on spring barley. 1. Estimation of genetical and environmental control of morphological and maturity characters. Theor Appl Genet 64:345–352
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Communicated by J. W. Snape
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Pooni, H.S., Virk, P.S., Coombs, D.T. et al. The genetical basis of hybrid vigour in a highly heterotic cross of Nicotiana tabacum . Theoret. Appl. Genetics 89, 1027–1031 (1994). https://doi.org/10.1007/BF00224534
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DOI: https://doi.org/10.1007/BF00224534