IMPROVEMENT OF WHITE CLOVER

The need to reduce economic and environmental costs of livestock agric ulture has led to a resurgence of interest in forage legumes, particul arly white clover. However, despite a recognition of the benefits accr uing from its high herbage quality and the nitrogen fixation from its symbiosis with the Rhizobium bacterium, the widespread use of white cl over by farmers has been inhibited by several perceived problems. Fore most amongst these have been a reputation for unreliable yield, lack o f persistency under intensive grazing and propensity to cause bloat in cattle. Conventional breeding techniques coupled with extensive genet ic resources and a growing understanding of the physiological basis of variation in yield and persistency have already resulted in the devel opment of new reliably productive varieties. These varieties will prov ide a cornerstone for sustainable livestock agriculture in upland and lowland areas of the UK and Europe. The successful application of tech niques of biotechnology to white clover has accelerated in recent year s. An array of approaches is now available which will open the way for its genetic manipulation and subsequent germplasm enhancement. These approaches range from the routine maintenance and propagation of plant s in vitro to the production of transgenic plants, and offer possibili ties of altering radically the nature of white clover in the future.