Abstract

Global climate change as a result, there is a change in rainfall and dry spell. Drought caused by insufficient rainfall or delayed. Thus, rice field under rainfall was affected that rice yield was decreased. Drought was a major problem in rice production in Thailand. Therefore, drought resistance should be increased by rice development to drought tolerance. The objective of this experiment was to evaluate drought tolerance of F₈ lines derived from crosses between upland and lowland rice under unwatered condition. The F₈ including 15 lines and 4 check varieties were planted in green house. At the tillering stage (30 days after planting), was unwatered. Every 2 days was collected leaf roll characteristics. The results showed that unwater after 16 days; KU1002-4-1 (PLG x SPR3) was highest average leaf roll as 8.33, on the other hand KU1001-7-1 (PLG x CNT1) was lowest average leaf roll as 3.00. Therefore, this line was well potential drought tolerance. Next step will be tested in upland condition.