Analysis of monitoring seed viability of rice cultivar germplasm in genebank

s: The germination rates of 14,003 rice cultivars, including 10 ecological groups which have been stored in the genebank for 20 years, were examined. The results showed that the mean percentage of germinating viability and germination rate were 88.07% and 91.11%, respectively. The germination rate for more than 87.45% of germplasm has been kept above 80%, but small number of the germplasm had lost their viability. Seed's viability of different groups dropped with different tendencies after stored at low temperature for a long time. Groups of middle-late cropping rice, late midget glutinous rice, early midget glutinous rice, introduced varieties and disease-resistant material showed stronger life for the storage conditions.The germination rate of japonica varieties, early indica varieties, breeding lines, late big-grain glutinous rice and upland rice groups was decreased remarkably and showed a weaker life for the storage conditions.