Submitted to: Journal of Heredity
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/1/2004
Publication Date: 5/1/2004
Citation: Bielenberg, D.G., Wany, Y., Fan, S., Reighard, G.L., Scorza, R., Abbott, A. 2004. A deletion affecting several gene candidates is present in the evergrowing peach mutant. Journal of Heredity. Interpretive Summary: Winter dormancy is one of the most basic processes that allow for the survival of plants in temperate climates. The genes that control dormancy are not known. If we understood the genetic control of dormancy, we could perhaps manipulate this process in order to produce hardier plants or to produce plants that grow better in warmer areas that do not experience long, cold winters. To study the genes that control dormancy, we used a peach tree that grows near the equator and does not have a dormancy requirement for normal growth and fruit production. We found a region of the genome (DNA) of this 'evergrowing' peach tree that appears to be responsible for this trait. We are now studying this important DNA region to discover the exact gene or genes that produce the 'evergrowing' trait.
Technical Abstract: Evergrowing (EVG) peach is one of only two described mutants affecting winter dormancy in woody perennial species. EVG peach does not set terminal buds, cease new leaf growth, nor enter into a dormant resting phase in response to winter conditions. The EVG mutation segregates in F2 progeny as a single recessive nuclear gene. A local molecular genetic linkage map around EVG was previously developed using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers, and a bacterial artificial chromosome (BAC) contig that contains the EVG mutation was assembled. A MADS box coding open reading frame (ORF) was found in a BAC of this contig and used as a probe. The probe detected a polymorphism between the wild-type and mutant genomes, and the polymorphism is indicative of a deletion in EVG peach. The EVG gene region contained six potential MADS-box transcription factor sequences, and the deletion in EVG affected at least four of these. The deletion was bracketed using RFLP analysis, which showed that it is contained within a segment of the genome no greater than 180 kb.