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Genetic basis for the occurrence of preharvest sprouting in wheat (Triticum aestivum L.)^*

Fernando Iraja Felix de Carvalho^I; Mauricio Sedrez dos Reis^II; Luiz Carlos Federizzis^I

^IFaculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Caixa Postal 776, 90001 Porto Alegre, RS, BrasiL Send correspondence to F.I.F.C.
^IIDepartamento de Fitotecnia, Universidade Federal de Santa Catarina, Rodovia SC 404, Km 4, 88041 Florianópolis, SC, Brasil

ABSTRACT

Heads of eight wheat (Triticum aestivum L) genotypes were treated by the water-immersion method to study the variability of preharvest sprouting. Preharvest sprouting was estimated on the basis of percentage of sprouting grains per head and sprouting score. To characterize the genetic basis of the trait, six generations (P₁, P₂, F₁, F₂, BC₁F₁ and BC₂F₁) of four crosses involving the genotypes Frocor, Jupateco 73, Lagoa Vermelha and IAS 54 were studied.
The trait investigated demonstrated the existence of variability among the genotypes studied and the genetic analyses showed the involvement of three independent genes with significant epistatic effects. The possible existence of relationships between epistatic effects, the presence of inhibitors, and duration of seed dormancy were discussed relative to the implications concerning selection of superior genotypes.

Keywords: genetic; preharvest; sprouting; wheat; Triticum aestivum.

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* Part of a thesis submitted by M.S.R. to the Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul in partial fulfillment of the requirements for the Masters Degree