Phytophthora frigida

FRIGIDA-ESSENTIAL 1 interacts genetically with FRIGIDA and FRIGIDA-LIKE 1 to promote the winter-annual habit of Arabidopsis thaliana.

Studies of natural variation have revealed that the winter-annual habit of many accessions of Arabidopsis is conferred by two genes, FRIGIDA (FRI) and FLOWERING LOCUS C (FLC), whose activities impose a vernalization requirement. To better understand the mechanism underlying the winter-annual habit, a genetic screen was performed to identify mutants that suppress the late-flowering behavior of a...

Two new Phytophthora species from South African Eucalyptus plantations.

A recent study to determine the cause of collar and root rot disease outbreaks of cold tolerant Eucalyptus species in South Africa resulted in the isolation of two putative new Phytophthora species. Based on phylogenetic comparisons using the ITS and beta-tubulin gene regions, these species were shown to be distinct from known species. These differences were also supported by robust morphologic...

The flavonoids of Arnica frigida and A. louiseana (Asteraceae)

DOWNIE, S. R., and K. E. DENFORD. 1986. The flavonoids of Arnicafrigida and A. louiseana (Asteraceae). Can. J . Bot. 64: 2748-2752. Forty-six populations within the Arnicafrigida Meyer ex Iljin louiseana Farr complex were examined for flavonoid content. Seven glycosides were isolated and six identified. Members of this complex were found to produce primarily quercetin and kaempferol 3-O-glycosi...

Phytophthora ramorum

Pleiotropy of FRIGIDA enhances the potential for multivariate adaptation

An evolutionary response to selection requires genetic variation; however, even if it exists, then the genetic details of the variation can constrain adaptation. In the simplest case, unlinked loci and uncorrelated phenotypes respond directly to multivariate selection and permit unrestricted paths to adaptive peaks. By contrast, 'antagonistic' pleiotropic loci may constrain adaptation by affect...