Survey of Agronomic Traits and Screening of Drought Tolerance of Recombinant Inbred Lines From Cross of Paddy Rice and Upland Rice

• Main Authors: Hsu, Wei-Jun, 許惟鈞
• Other Authors: Wen-Lii Huang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/08672328440097369126

碩士 === 國立嘉義大學 === 農藝學系研究所 === 103 === This study aimed on using linkage analysis strategy to locate the drought tolerance related genes quantitative traits loci (QTLs) in rice. One of the parental lines, NKY982055 (NKY) is japonica type, obtained from Tainan District Agricultural Research and Extension Station and another parental line, CD-3, an indigenous species as for upland rice, is from the native tribes in Chiayi area. In 2009, cross was made in the first crop season, after the F2 generation, each individual line from the family was picked up for further breeding; the generation family has been up to F10, at least 140 of the lines to establish these hybrid combinations of recombinant inbred lines (RILs). From the results of agronomic traits investigation and drought tolerance screening, the plant morphology, growth characteristics and grain appearance, can clearly distinguish the differences of two parents. The plant height of maternal, NKY is significantly shorter than the paternal, CD-3. As for the tiller numbers, panicles, grain number per panicle, fertility and grain yield per plant, NKY are higher than those of CD-3. On the contrary, NKY’s ear length, ear weight, and grain weight are significantly lower than those of CD-3. NKY’s heading date for two crop seasons showed no obvious differences; however, for CD-3 in the second crop season, the heading date was quite shorter. This result indicated that NKY is a non-photosensitive and spike-type rice strain while CD-3 is a photosensitive and ear heavy strain. In addition, NKY’s grains are typically Japanese-style, short and round appearance, while for CD-3, long, red and glutinous grains. The survey results indicated that the agronomic traits and physiological characteristics of cross segregated family of RILs exhibited a high degree of variability. Furthermore, the inter-trait correlation analysis showed that the widely known yield components were highly correlated but the drought index, DIR7 and heading date indicated a highly positively correlation; presents a highly negatively correlation between the number of tillers and panicles presentation. This demonstrated this cross population under drought stress, a higher number of tillers and spikes could maintain a certain grain yield per plant. Besides, this study used 45 groups of SNP molecular markers combined into six sets of multiplex reaction to analysis the polymorphism of the parental lines and RILs. The regression analysis indicated that nine functional candidate genes are significantly related to drought, also nine functional candidate genes which separated in different chromosomes are significantly related to grain yield. It is worthy for further exploration of candidate gene expression patterns associated with physiological functions in order to clarify the nature of their association with drought.