Evaluation of Rice Seedling Tolerance to Constant and Intermittent Low Temperature Stress

作     者：Sang-Ic KIM Dong-min KIM Thomas H.TAI 

作者机构：USDA-ARS Crops Pathology and Genetics Research UnitDepartment of Plant Sciences-Mail Stop 1University of CaliforniaDavisCA 95616USA Department of AgronomyChungnam National UniversityDaejeon 305-764Republic of Korea 

出 版 物：《Rice science》 (水稻科学（英文版）)

年 卷 期：2012年第19卷第4期

页      面：295-308页

学科分类：0710[理学-生物学] 0831[工学-生物医学工程（可授工学、理学、医学学位）] 09[农学] 0901[农学-作物学] 0836[工学-生物工程] 0902[农学-园艺学] 

主　　题：rice seedling cold tolerance quantitative trait locus advanced backcross line low temperature stress 

摘      要：M202, IR50 and advanced backcross （BC4F6） lines carrying the cold tolerance QTLs qCTS4 and qCTS12 were evaluated using three low temperature stress assays （constant, intermittent and constant with recovery period）. Under constant stress, two BC4F6 lines （MIb 4853-9 and MIb 6885-2） exhibited differences in seedling growth and accumulation of stress-related compounds although both carry the two QTLs in the IRS0 background. Differences between these lines were also observed in the constant with recovery period assay, although both of them performed comparably under intermittent stress, MIb 6885-2 performed more similarly to M202 in the constant and constant with recovery period assays, suggesting that this line contains an introgressed region（s） not present in MIb 4853-9. The three assays were also applied to assess variations in cold tolerance in a set of diverse germplasms. Performance metrics and visual ratings were comparable for evaluating tolerance to constant stress. However, differences in response to intermittent stress were more evident from growth and total chlorophyll measurements than from visual ratings. With regard to the constant with recovery period assay, about 15% of the germplasm accessions did not recover. However, some lines which exhibited chilling injuries of comparable severity were able to overcome them. This recovery phenotype may improve rice performance in the field and warrant further investigation.