Occurrence of partial hybrids in wide crosses between sunflower ( Helianthus annuus) and perennial species H. mollisand H. orgyalis.

Hybridisation between the annual diploid sunflower ( Helianthus annuus)and the perennial diploid species Helianthus mollis and Helianthus orgyalis was obtained by means of a normal crossing procedure or embryo rescue. Hybridisation success was low. All plants examined cytologically appeared to be diploid.

Partial hybridization in wide crosses between cultivated sunflower and the perennial Helianthus species H. mollis and H. orgyalis.

To obtain introgressed sunflower lines with improved disease resistance, interspecific crosses were performed with foreign perennial species. We report on several unusual features displayed by these hybrid plants. The methods used to produce the kernels affected yield and genotypes of progeny.

Specifying the introgressed regions from H. argophyllus in cultivated sunflower (Helianthus annuus L.) to mark Phomopsis resistance genes.

A method based upon targetting of introgressed markers in a Phomopsis-resistant line (R) of cultivated sunflower, issuing from a H. argophyllus cross was used to mark the Phomopsis resistance regions. Our study was based upon 203 F(3) families derived from a cross between an inbred line susceptible to Phomopsis (S1) and the introgressed resistant line (R).

Mapping genetic factors controlling pollen viability in an interspecific cross in Helianthus sect. Helianthus.

Segregation of 48 genetic markers, including one CMS restorer gene, one morphological character gene, six isozymes and 40 RAPD loci, was scored in a backcross progeny of an interspecific hybrid H. argophyllusxH. annuus cv RHA274.

Mitochondrial DNA RFLP and genetical studies of cytoplasmic male sterility in the sunflower (Helianthus annuus).

Fifteen sunflower (Helianthus annuus L.) cytoplasmic male-sterile, and a single male-fertile, cytotypes were studied by both mtDNA (mitochondrial DNA) restriction fragment length polymorphism (RFLP) and genetical analysis of male-fertility restoration patterns. It was found by multivariate analysis that the two methods of identification of cytoplasmic male sterility (CMS) should be of use in sunflower breeding programs.