Classic Genetics and Breeding - Genetics, Genomics and Breeding of Crop Plants - page 56

2
Classic Genetics and Breeding
Felicity Vear
ABSTRACT
Sunflower hybrids were first developed in sunflower 60 years ago
and with the discovery of cytoplasmic male sterility have become the
main type of variety since 1970. Breeding programs use mostly
pedigree, recurrent and backcross selection. The main characters
selected for are seed yield, oil content and oil type, earliness, height,
disease, insect and drought resistance. Except for a few major genes,
until 1995, breeding depended only on phenotypic observations, but
in the last 10 years genomics have improved knowledge of the
genetics of quantitative characters and marker-assisted selection has
started to become a practical tool.
Keywords: cytoplasmic male sterility; hybrid; inbred line; major genes;
quantitative inheritance; recurrent selection; resistance
2.1 Introduction
Since sunflowers are cross-pollinated and show heterosis, the most vigorous
plants, producing the best yields, are heterozygotes. The first sunflower
varieties maintained by the Russian farmers were heterogeneous open-
pollinated populations of mixtures of natural hybrids. From 1920 to 1970,
more characterized populations were bred, especially in Russia, at the
VNIIMK station at Krasnodar. The best known were VNIIMK 6540, VNIIMK
8931 and Peredovik. There were also Argentinean, French, Canadian and
Romanian varieties. All these populations constituted the main genetic
resources of cultivated sunflower until the mid-1970s. They are now
INRA, UMR 1095, Domaine de Crouelle, 234 Ave du Brezet, 63000 Clermont-Ferrand,
France; e-mail: [e-mail]