RICE GENETIC RESOURCES: CONSERVATION AND UTILISATION IN MALAYSIA

Rice shares similar importance in most Asian countries as a staple food crop and in Malaysia, the crop supports the livelihood of more than 200,000 farm families. Rice is not only diverse in its landscape but also rich in genetic diversity. Collecting expeditions to collect rice varieties were initiated in late 1950 s but gained much attention in 1970 s when high yielding varieties (HYVs), representing a new form of genetic technology, was rapidly adopted in double-cropping areas in the country. Now, the rice germplasm collection stands at 11,470 registered accessions of which 75% are of local origin. Each rice accession is characterised for important morpho-agronomic and genetic evaluation traits. Genetic diversity with respect to the important traits has been established, namely for culm height, panicle length, maturation, and also reactions to blast, bacterial leaf blight (BLB) and brown plant hopper (BPH). Generally, the local accessions were taller because majority of them are traditional varieties. Therefore, introduced germplasm which consists mostly of advanced breeding lines had been used widely in crossing programmes to incorporate semi-dwarfness through breeding and selection. For panicle length, the local germplasm are preferable for use as parental materials because of its longer average length. Majority of accessions which had been introduced were of short maturation as compared to the local accessions. Therefore, they had been extensively utilised to incorporate and fix short duration trait into new HYVs. For disease and pest resistance, majority of gene donors are generally selected from introduced germplasm. However, results of recent screening showed that some local germplasm accession is found to be resistant to the pests and diseases. 30% of the local germplasm is very resistant to blast fungus and therefore, represents the potential sources of resistance donors. For BPH and BLB, a significant number of accessions had been found to be resistant, and therefore, they had begun to be used as parental material in varietal improvement programmes. The conserved germplasm has been an important asset in the past and the present, and will continue to be the invaluable rice genepool to fuel our rice improvement programme in the future. The potential of local as well as foreign germplasm materials as gene donors is well demonstrated when they had been successfully utilised to breed our high yielding lines and varieties. To date, a total of 33 HYVs have been developed and released for commercial planting. This paper highlights the germplasm banking activities and related findings about the conserved rice germplasm in MARDI Rice Genebank.