Breeding Forage Plants in the Genome Era

Abstract

Forage plant breeding has been largely based on phenotypic selection following sexual recombination of natural genetic variation found between and within ecotypes. Advances in plant genetic manipulation over the last 15 years have provided convincing evidence that these powerful technologies can complement and enhance plant breeding programs. Significant progress in the establishment of the methodologies required for the molecular breeding of forage plants has been made. Examples of current products and approaches for the application of these methodologies to forage grass and legume improvement are outlined. Large-scale genomic analysis of many organisms is under way with human, arabidopsis and rice genome sequences almost completed . Forage plant breeding is just now entering the genome era. The plethora of new technologies and tools now available for high-throughput gene discovery and genome-wide gene expression analysis have opened up opportunities for innovative applications in the identification, functional characterisation and use of genes of value in forage production systems and beyond. Examples of these opportunities, such as 'molecular phenotyping', ' symbio-genomics' and 'xeno-genomics ' are introduced.G. Spangenberg (ed.), Molecular Breeding 01Forage Crops , 1-39.

Breeding for genetic improvement of forage plants in relation to increasing animal production with reduced environmental footprint

“…Modern breeding techniques such as maker-assisted selection allied with high throughput phenotyping can increase the speed and precision with which traits can be introduced and selected into and from breeding populations (Xu and Crouch, 2008). This is based on detection of DNA variation among individuals (Bowley, 1997;Henry, 2001;Spangenberg et al, 2001) and quantitative trait locus (QTL) analysis for dissecting complex traits and assessing gene effects. Molecular-based techniques offer considerable potential advantages, especially in speeding up breeding of forage crops that are typically outbreeding perennial species where evaluation of advanced lines in plots takes several years and where studies involving animals or impacts on the environment are time consuming and expensive.…”

Genetics and molecular breeding in Lolium/Festuca grass species complex

“…Application of transgenesis to forage plant improvement has focused on the development of transformation events with unique genetic variation and on studies on the molecular dissection of plant biosynthetic pathways and developmental processes of high relevance for forage production (Spangenberg et al . 1998; Spangenberg et al . 2001).…”

“…Gene technology and the production of transgenic plants offer the opportunity to generate unique genetic variation. Application of transgenesis to forage plant improvement has focused on the development of transformation events with unique genetic variation and on studies on the molecular dissection of plant biosynthetic pathways and developmental processes of high relevance for forage production (Spangenberg et al 1998;Spangenberg et al 2001). The biolistic methodology, based on particle bombardment, has been the most successful means of transforming grasses.…”

Ecological risk assessment of transgenic pasture plants: a community gradient modelling approach

“…Given the large scale at which pasture plants are utilized in many countries worldwide, and the rapid development of transgenic lines of many species in recent years (Dear et al. 1997; Spangenberg et al. 2001), there is a strong need for studies of the performance of GM pasture plants in target and non‐target plant communities, including identification of the factors that limit the persistence or spread of individual species on different spatial scales.…”

“…However, most transgenic pasture plants have yet to be commercialized on a large scale, and little is known about their capacity to persist in species-rich plant communities such as improved pasture or native vegetation. Given the large scale at which pasture plants are utilized in many countries worldwide, and the rapid development of transgenic lines of many species in recent years (Dear et al 1997;Spangenberg et al 2001), there is a strong need for studies of the performance of GM pasture plants in target and non-target plant communities, including identification of the factors that limit the persistence or spread of individual species on different spatial scales. This is particularly true in regions where remnant native vegetation communities have high conservation value (e.g.…”