Abstract: Rice panicle traits have a distinct effect on yield, and the exploration and research of related genes play a crucial role in ensuring national food security. In this study, we used the indica rice HZ, the japonica rice Nekken2 and 120 recombinant inbred lines population constructed from them as experimental materials to measure panicle length, grain number per panicle, seed-setting rate, stigma exsertion rate, number of primary branches and other panicle traits. We combined the high-density genetic map for QTL mapping, a total of 31 QTLs were detected on chromosome 1, 2, 3, 4, 5, 6, 10 and 11, among which 2 LOD values were as high as 5.45 and 5.28. By analyzing the candidate genes in the QTL interval, the related genes that may affect the panicle traits were screened out, and qRT-PCR was used for gene expression analysis, which revealed that the expression levels of LOC_Os05g05490, LOC_Os05g06150, LOC_Os03g11700, LOC_Os03g12430, LOC_Os05g28720, LOC_Os05g30890, LOC_Os05g31740 and LOC_Os02g17880 were significantly different between the parents. Among these genes, the first five genes encode tripartite pentapeptide repeat proteins, while the latter three genes encode glycosyltransferases. This study identified 31 QTLs related to panicle traits, laying a theoretical basis for further localization and cloning of related genes and breeding new high-yield rice varieties.

Key words: Oryza sativa (rice), panicle traits, QTL mapping, candidate genes, high-yield