TY  - EJOU
AU  - Guo, Xin 
AU  - Qi, Shuangting 
AU  - Duan, Lian 
AU  - Lou, Xueyuan 
AU  - Wang, Xian 
AU  - He, Songlin 
AU  - Cheng, Fangyun 

TI  - Association Mapping of Hundred-Grain Weight in <i>Paeonia ostii</i> Using SSR Markers of Transcription Factors from the Comparative Transcriptome
T2  - Phyton-International Journal of Experimental Botany

PY  - 2026
VL  - 95
IS  - 4
SN  - 1851-5657

AB  - Plant quantitative trait allelic variation stems from complex regulatory networks. Tree peony, which is native to China, is a unique woody plant with ornamental, medicinal, and oil-producing value. <i>Paeonia ostii</i>, as an important species of tree peony, has emerged as a novel woody oil crop in recent years. However, research on functional genes associated with yield traits in <i>P. ostii</i> remains relatively limited. To gain deeper insights into the genetic architecture underlying one of the three key yield components—grain weight—in this study, a genome-wide association map for 123 unrelated <i>P. ostii</i> was constructed by integrating short-read and long-read sequencing. From 959 screened yield-related candidate transcription factors, 57 polymorphic expressed sequence tag-simple sequence repeats (EST-SSRs) were identified. In combination with 24 previously reported polymorphic EST-SSRs linked to tree peony seed yield, 81 markers were utilized for genotyping 123 <i>P. ostii</i> materials. These EST-SSRs showed high genetic diversity and low linkage disequilibrium. Additionally, population structure analysis revealed two distinct subgroups within the mapping population. Furthermore, 21 EST-SSRs were significantly associated with hundred-grain weight according to mixed linear model (MLM) association analysis. These loci primarily originated from the AP2, TCP, YAB, WRKY, WD, BHLH, and MADS-box gene families, contributing to phenotypic variation at rates ranging from 9.15% to 35.94%. Through sequence alignment analysis, we determined that <i>WRI1</i>, <i>ERF7</i>, <i>NGAL3</i>, and <i>YAB1</i> might serve as key candidate genes regulating seed weight in <i>P. ostii</i>, highlighting their significant research value and warranting further investigation. The findings of this study provide valuable resources for elucidating allelic variation in the quantitative traits of oil-producing woody perennials.
KW  - <i>P. ostii</i>; hundred-grain weight; association analysis; EST-SSR; transcription factors

DO  - 10.32604/phyton.2026.076905