EVOLUTION OF BRASSICA RAPA L. (CRUCIFERAE) POPULATIONS IN INTRA‐ AND INTERSPECIFIC COMPETITION

An Experimental Study of Competitive Performance in Brassica rapa (Cruciferae)

Growth chamber experiments with rapid-cycling Brassica rapa were designed to estimate the signsand magnitudes ofthe genetic correlationsfor plant performance in each ofthree conditions: no-competition (isolated plants), intraspecific competition, and interspecific competition with Raphanus sativa. Biomass and flower number were highest in the no-competition treatment, intermediate under intrasp...

Stable Bacillus thuringiensis (Bt) toxin content in interspecific F1 and backcross populations of wild Brassica rapa after Bt gene transfer.

Stable expression of a transgene may lead to increased fitness for wild plants after acquiring the transgene via crop-weed hybridization. Here, we investigate the stability of Bt toxin content in wild Brassica rapa acquiring the Bt gene from Bt Brassica napus. The Bt toxin content in nine Bt-expressing B. napus lines was 0.80-1.70 micro g/g leaf tissue throughout the growing season. These nine ...

Factors Controlling Intra- and Interspecific Competition in Bryozoans

Interspecific hybridization, polyploidization, and backcross of Brassica oleracea var. alboglabra with B. rapa var. purpurea morphologically recapitulate the evolution of Brassica vegetables

Brassica oleracea and B. rapa are two important vegetable crops. Both are composed of dozens of subspecies encompassing hundreds of varieties and cultivars. Synthetic B. napus with these two plants has been used extensively as a research model for the investigation of allopolyploid evolution. However, the mechanism underlying the explosive evolution of hundreds of varieties of B. oleracea and B...

Rapid genome‐wide evolution in Brassica rapa populations following drought revealed by sequencing of ancestral and descendant gene pools

There is increasing evidence that evolution can occur rapidly in response to selection. Recent advances in sequencing suggest the possibility of documenting genetic changes as they occur in populations, thus uncovering the genetic basis of evolution, particularly if samples are available from both before and after selection. Here, we had a unique opportunity to directly assess genetic changes i...