Satellite Symposium 5: Molecular Breeding
Description
Ryegrass (Lolium perenne) is an important forage crop in New Zealand. The work presented here has the goal of developing a system for complete and arbitrary control of the transition from vegetative to floral development. For this, we have pursued an integrated approach utilising genomics with both forward and reverse genetics. Like other model plants, photoperiodic and vernalization pathways are presumed to be operating in ryegrass and control the activity of the meristem identity/floral patterning genes. The candidate gene approach targeting the photoperiodic pathway is described in an accompanying abstract (Gagic et al.). Other candidate genes include the meristem identity gene LEAFY and a range of the MADS box transcription factors. Relevant expression profiles are established for these genes, i.e. vernalization time course at weekly intervals, and daily and circadian collections during the secondary induction. A detailed genetic map of ryegrass has been developed at AgResearch (see abstract by Faville et al.) which we are using to map candidate genes. We are also conducting detailed phenotypic analysis of the flowering behaviour variation within this population in an effort to isolate relevant QTLs. Ryegrass transformation has been used to ascertain functions of the candidate genes and to manipulate flowering time control directly. We are developing a universal switch to turn on the flowering that consists of a cassette of the arabidopsis genes under a control of a chemically inducible promoter.
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Controlled Flowering Project for Lolium Perenne at Agresearch: an Overview
Ryegrass (Lolium perenne) is an important forage crop in New Zealand. The work presented here has the goal of developing a system for complete and arbitrary control of the transition from vegetative to floral development. For this, we have pursued an integrated approach utilising genomics with both forward and reverse genetics. Like other model plants, photoperiodic and vernalization pathways are presumed to be operating in ryegrass and control the activity of the meristem identity/floral patterning genes. The candidate gene approach targeting the photoperiodic pathway is described in an accompanying abstract (Gagic et al.). Other candidate genes include the meristem identity gene LEAFY and a range of the MADS box transcription factors. Relevant expression profiles are established for these genes, i.e. vernalization time course at weekly intervals, and daily and circadian collections during the secondary induction. A detailed genetic map of ryegrass has been developed at AgResearch (see abstract by Faville et al.) which we are using to map candidate genes. We are also conducting detailed phenotypic analysis of the flowering behaviour variation within this population in an effort to isolate relevant QTLs. Ryegrass transformation has been used to ascertain functions of the candidate genes and to manipulate flowering time control directly. We are developing a universal switch to turn on the flowering that consists of a cassette of the arabidopsis genes under a control of a chemically inducible promoter.
