Florescence duration of winter rape in breeding for heterosis

Abstract

Aim. Dynamics and synchronism of florescence of winter rape sterile and fertile forms were studied to obtain high-quality stock seeds of F₁.hybrids.

Material. Lines of Ogu-inra, Polima sterility types and eight fertile forms were studied. It was found that three periods could be distinguished in provision of sterile forms with pollen.

Results. In the first period of florescence from the third ten-day interval of April to the third ten-day interval of May sufficient amount of pollen is produced. Over this period 89 % of floriferous fertile flowers accrue to 68.5 % of sterile flowers. It was revealed that at the end of florescence (the third ten-day interval of June) of sterile forms there was no pollen of fertile forms. Around 6 % of sterile flowers bear blossom during this period.

Conclusions. In the production of F₁ hybrid seeds the first period of florescence of sterile forms ensures obtainment of high-quality stock seeds, and biological contamination can be observed during the second and third periods. Recommendations regarding further investigation of paternal forms to improve winter rape F₁ hybrid seed industry are given.