EFFECTIVE METHODS FOR DORMANCY BREAKING OF 15 NEW-IMPROVED RICE VARIETIES TO ENHANCE THE VALIDITY OF GERMINATION TEST

Dormancy is acharacteristic of seeds, which is genetically inherited and is an important factor in the germination \nof seeds. Dormancy in rice serves as a mechanism of survival by protecting the seed from germinating in the \nmother-plants, however it becomes a problem in germination evaluation as part of seed quality testing when \nmethods for overcoming dormancy is not effective.Seven different treatments were used to determine seed \ndormancy of 15 new improved-varieties. Results showed all varieties tested have a diversity of dormancies. A \ntotal of 15 varieties showed intensity of dormancy varied between 47-98%.Persistency of dormancy of the 15 \nvarieties ranged between 2-8 weeks. At the beginning of seed storage (0 week), the results showed that 14 out of \n15 varieties treated by drying at temperature of 50oC for 48 h and continued by soaking the seeds in 10 ppm GA3 \nsolution for 24 h gave means value of seed germination ≥85%, whereas the control seeds of 15 tested varieties \nshowed means value of germination below 60%. This method of breaking seed dormancy is considered to be \neffective and available to be used by seed analysts on rice seed germination testing specifically for those 14 \nvarieties tested.