Identification of 1,3-1,4-β-D-glucanase (OsDLH) genes and analysis of haplotype diversity in rice

1,3-1,4-β-D-glucanase (<i>DLH</i>) is a fibrolytic enzyme playing important roles in plant growth, development, and stress response. In this study, we identified 11 <i>DLH</i> genes in <i>japonica</i> rice (Nipponbare), and analyzed their chromosomal localization, physicochemical properties, subcellular localization, evolutionary relationships, and collinearity. We also performed <i>cis</i>-acting element identification, gene expression profiling, and qPCR verification under abiotic stress, as well as conducted diversity analysis of gene-CDS-haplotypes (gcHaps) in 3,010 rice germplasms to dissect the potential functions of these <i>OsDLH</i> genes. The results showed that <i>OsDLH1, OsDLH5</i>, and <i>OsDLH10</i> can be utilized to improve the tolerance of rice to abiotic stress. <i>OsDLH1</i>, <i>OsDLH2</i> and <i>OsDLH8</i> are highly expressed in roots. Under high-salt stress, the expression of <i>OsDLH6</i> and <i>OsDLH10</i> in stems and leaves increased. These results indicated that <i>OsDLH1</i> and <i>OsDLH5</i> have specific expression patterns in response to different environmental signals, implying that they may play different roles in the growth and development process of rice and the stress response mechanism. Haplotype analysis indicated population differentiation of the Os<i>DLH</i> gene family in rice. The major gcHaps at most <i>OsDLH</i> loci are significantly associated with yield traits. Some genes of this family have potential application value in improving stress resistance and yield traits of rice.