PacBio data of Leymus chinensis

Sodic soil is widely distributed around the world. Alkali stress caused by sodic soils is one of the important environmental factors in restricting agriculture production. Halophytes not only have value for improving understanding of salinity stress or alkali stress tolerance mechanisms, but also can provide candidate genes for stress tolerance improvements of crop plants. Leymus chinensis is constructive halophyte species in alkalized grassland in northern China with high forage value. L. chinensis is close relative of wheat plants. In this work, we exposed the seedlings of L. chinensis to alkali stress (NaHCO3/Na2CO3, 9:1; 200 mM, pH 8.8). To elucidate the gene expression response mechanism of this species to alkali stress, we used PacBio technology to obtain reference full-length transcript sequences for RNAseq analysis of alkali stress response. Additionally, we also conducted the biochemical analysis and anatomical analysis. The results showed that L. chinensis shared many alkali tolerance mechanisms with glycophytes. For example, under alkali stress, the NHX expression response and nitrogen metabolism response mechanisms of L. chinensis were similar to those of glycophyte. Higher stability of photosynthetic system under alkali stress may be prominent alkali tolerance trait of L. chinensis. Photosynthetic pigments of L. chinensis was unaffected by long-term strong alkali stress but the pigment contents of glycophyte (wheat) severely decreased under alkali stress. Compared with glycophytes, L. chinensis may have strong capacity to detoxicate the toxicity of Na+ to organelles and cytoplasmic proteins. Enhanced expression of dehydrin and LEA genes and increased accumulation of carbohydrates may contribute the development of its this capacity.