Theoretical potential of biotechniques in crop improvement

For the past decade, biotechnology has been promising to deliver new methods and new types of variation to the plant breeder, but only in the last 2 or 3 years has this become a reality. A wide array of new molecular biology and genetic manipulation techniques is now available, which should enable plant breeders to produce improved plants more easily and to develop varieties and cultivars with higher and more sustainable yields, improved quality and composition, greater resistance to pests and diseases, and improved tolerance of climatic and edaphic stresses. Opinions on the use of genetic manipulation differ widely, but in our view, any technology that helps extend the range of variation and manipulate the genetic material of the plant has a role to play in developing new and improved crops. Obstacles that still exist in the application of biotechnology, particularly to important cereals and grasses, are likely to be overcome soon. Improvements will result from the application of a range of technologies, from those giving rise to single base changes to those that modify whole genomes. To effect these changes, plant breeders need to understand the potential of biotechnology, and biotechnologists, of the needs of breeders

Identification of perennial ryegrass (Lolium perenne (L.)) and meadow fescue (Festuca pratensis (Huds.)) candidate orthologous sequences to the rice Hd1(Se1) and barley HvCO1 CONSTANS-like genes through comparative mapping and microsynteny

Microsynteny with rice and comparative genetic mapping were used to identify candidate orthologous sequences to the rice Hd1(Se1) gene in Lolium perenne and Festuca pratensis. A F. pratensis bacterial artificial chromosome (BAC) library was screened with a marker (S2539) physically close to Hd1 in rice to identify the equivalent genomic region in F. pratensis. The BAC sequence was used to identify and map the same region in L. perenne. Predicted protein sequences for L. perenne and F. pratensis Hd1 candidates (LpHd1 and FpHd1) indicated they were CONSTANS-like zinc finger proteins with 61-62% sequence identity with rice Hd1 and 72% identity with barley HvCO1. LpHd1 and FpHd1 were physically linked in their respective genomes (< 4 kb) to marker S2539, which was mapped to L. perenne chromosome 7. The identified candidate orthologues of rice Hd1 and barley HvCO1 in L. perenne and F. pratensis map to chromosome 7, a region of the L. perenne genome which has a degree of conserved genetic synteny both with rice chromosome 6, which contains Hd1, and barley chromosome 7H, which contains HvCO1

Synteny between a major heading-date QTL in perennial ryegrass (Lolium perenne L.) and the Hd3 heading-date locus in rice

The genetic control of induction to flowering has been studied extensively in both model and crop species because of its fundamental biological and economic significance. An ultimate aim of many of these studies has been the application of the understanding of control of flowering that can be gained from the study of model species, to the improvement of crop species. The present study identifies a region of genetic synteny between rice and Lolium perenne, which contains the Hd3 heading-date QTL in rice and a major QTL, accounting for up to 70% of the variance associated with heading date in L. perenne. The identification of synteny between rice and L. perenne in this region demonstrates the direct applicability of the rice genome to the understanding of biological processes in other species. Specifically, this syntenic relationship will greatly facilitate the genetic dissection of aspects of heading-date induction by enabling the magnitude of the genetic component of the heading-date QTL in L. perenne to be combined with the sequencing and annotation information from the rice genome