Initial developmental rate delay in modern highly productive cultivars of winter bread wheat from West Europe

Aim. To evaluate the vernalization requirement duration and sensitivity to photoperiod in the set of modern high yielding winter bread wheat cultivars from West Europe which are proposed for production in Ukraine. Methods. Planting in natural and shortened photoperiods followed by artificial vernalizing variants of 5-days green seedlings have been used for heading dates registration. Results. Many foreign cultivars revealed the durable vernalization requirement and strong photosensitivity. Few stocks were characterized by the week analogous physiological reactions, which are typical in most modern Ukrainian cultivars and breeding lines. Conclusions. Reveled data confirmed the adaptive value of discussed properties for specific environment which are similar to Ukrainian one in many zones of winter wheat cultivation. And they refute the assertion that strong photosensitivity and durable vernalization requirement limit the improvement of yield potential by selection. Keywords: winter bread wheat, vernalization requirement, photosensitivity, modern cultivars from West Europe.