Observações sobre compatibilidade no gênero brassica
Palavras-chave:
compatibilidade inter-específica, fertilidade cruzamentos asiáticos, espécies Brassica, número óvulos, polinização isoladaResumo
Several species and varieties of Brassica were interbred, for the purpose of studying their phylogenetic relationship. The index “seed: ovules” was adopted as a criterion te evaluate the compatibility among them.
The fertility of the hybrids was studied by means of comparison with that of the parents. As as result of these studies, it was concluded that Br. chinensis, Br. pekinensis, and Br. rapa (varieties Rst and TR) seem to belong to the same taxonomic group, whereas Br. japonica seems to form part of another group considerably apart.
Such conclusion received further support from the study of the compatibility between Br. oleracea and the above mentioned species. Br. japonica showed to be much closer to Br. oleracea than anyone of the other species studied.
As illustration, the fertility of the hybrids Br. chinensis x Br. rapa, its reciprocal, and Br. pekinensis x Br. rapa was submitted to a genetic analysis, carried down to the second generation (Fy). The results seem to indicate the existence of a trimerous inheritance, in which the seli-fertility is condicioned by a triple dominance.
Referências
Bailey, L. H. (1922): Art. Brassica, Stand Cycl. of Horticulture.
Brieger, F. (1930): Selbststerilitdt und Kreuzungssterilitéit in Tier — und Pilanzenreich. Verlag Springer. Berlin.
Correns, C. (1913): Selbststerilitdt und Individualstoffe, Biol. Zentralbl. 33.
[autor não informado] (1928): Neue Untersuchungen an selbststerilen Pflanzen. Biologisches Zentralblatt 48.
Haga, T. (1938): Relationship of genom to second. pair.in Br. Jap. Journ. Genet. 13.
Howard,R . W.(1942a): Effects of Polyploidy and Hybrid. on seed size in crosses between Br. chin. and Br. Carin.
[autor não informado] (1942b): Heteroauxin and prod. of tetraploid shoots by the callus method. in Br. oleracea. Jounal of Gen.44.
[autor não informado] (1942c): Selfincompatibility in polypl. forms of Brassica and Raphanus. Nature. London 149.
Karpetshenko (1937): Experimentelle Gewinnung tetraploider Bastarde von Brassica oleracea x Br. carinata. Bull. Appl. Bot. II. 7.
Koller. S. (1940): Graphische Tafeln zur Beurteilung statistischer Zahlen. Steinkopff Leipzig.
Memoria, J. P. (1948): Dedução da equação da curva normal. Ceres pag. 321.
Moringa, T. (1929/30): Interspec.hybr.in Brassica. Cytol. I.
Nagaharu, U. (1935): Genome-analysis in Brassica. Jap. J. Bot. 7.
Nelson; A. (1927): Fertility in Brassica. Journ. of Genetics 18. 2.
Roemer, W. (1935): Fruchtbarkeit und Vererbung bei Brassica — Artkreuzungen. Zeitschrift fir Ziichtung 20.
Schiemann, E. (1932): Entstehung der Kulturpflanzen. Handb. d. Vererb. III.
Sinskaia, F. (1927): Genosystem. invest. of cultural Brassica. Bull. Appl. Bot. 17.
Stout, R. (1931): Pollen tube behaviour in Br. pekinensis. Amer. Journ. of Bot. 18.
