Abstract Detail

Ecophysiology

Baker, Robert (Rob) L. [1], Yarkhunova, Yulia [2], Ewers, Brent [2], Weinig, Cynthia [2].

Polyploidy: consequences for leaf structure and function in Brassica triangle species.

The Brassica triangle consists of six species ranging from n=8 to n=19 with combinations of three distinct genomes. Ancestral species at each point of the triangle (Brassica rapa, n=10, AA; Brassica nigra, n=8, BB; and Brassica oleracea, n=9, CC) have interbred to produce multiple allotetraploid progeny (Brassica carinata, n=17, BBCC; Brassica juncea, n=18, AABB, and Brassica napus, n=19, AACC). Within each species, varieties have been artificially selected for different targets of harvest: underground storage organs (turnips), leafy greens (cabbages, bok choy), axillary branches (brussels sprouts), floral parts (cauliflower, broccolinis), or seeds (oil seeds). Additionally, within a single diploid (B. rapa), we have observed physiological differences that were strongly associated with stomatal density, leaf anatomy, and crop type. We grew representatives from each of the six Brassica triangle species in a common, greenhouse environment. For each plant we measured photosynthetic rates, stomatal conductance, and water use efficiency. Further, we quantified anatomic structures of leaves to understand how polyploidy effects leaf-level physiology and anatomy. Repeated allotetraploid events and multiple genomic combinations as well as overlapping targets of artificial selection make the Brassica triangle an excellent system for exploring variation in the connection between anatomic structure and physiological function as well as studying the effects of artificial selection and polyploidy.

1 - University of Wyoming, Botany, 1000 E. University Ave, Laraie, WY, 82070, USA
2 - University of Wyoming, Botany, 1000 E. University Ave, Laramie, WY, 82070, USA

Keywords:
allotetraploid
leaf anatomy
Brassica
leaf function
physiology
Polyploidy
leaf structure.

Presentation Type: Oral Paper:Papers for Topics
Session: 41
Location: Salon 16/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 11:00 AM
Number: 41004
Abstract ID:697
Candidate for Awards:None