Shortening of the development cycle in winter rape (Brassica napus var. oleifera L.) by grafting nonvernalized scions on generative stock

Abstract

The conditions were investigated under which the development cycle in winter rape could be markedly reduced by grafting. Scions from non vernalized seedlings were grafted onto stock plants beginning their generative phase. Winter rape plants vernalized under natural field conditions and spring rape plants in the initial generative phase were used as stock. Best results were obtained by grafting scions from plants at the stage of 4 leaves, i.e. after 3 weeks of growth, onto winter rape stock. With such scions the effectiveness of graftings was high and seed crops were obtained 170 days earlier than under natural field conditions of growth and 80 days earlier than under artificial conditions. Scions grafted onto winter rape stock produced more siliques than those on spring rape. Grafting of scions after cutting off their apical meristems allowed formation of side shoots and consequently resulted in higher yields of siliques; the formation of siliques, however, was delayed by about 10 days as compared to grafts with apical meristems.