Kobresia plants are important forage resources on the Qinghai-Tibet Plateau and are essential in maintaining the ecological balance of grasslands. Therefore, it is beneficial to obtain Kobresia genome resources and study the adaptive characteristics of Kobresia plants on the Qinghai-Tibetan Plateau. Previously, we have assembled the genome of Carex littledalei (Kobresia littledalei), which is a diploid with 29 chromosomes. In this study, we assembled genomes of Carex parvula (Kobresia pygmaea) and Carex kokanica (Kobresia royleana) via using Illumina and PacBio sequencing data, which were about 783.49 Mb and 673.40 Mb in size, respectively. And 45,002 or 36,709 protein-coding genes were further annotated in the genome of C. parvula or C. kokanica. Phylogenetic analysis indicated that Kobresia in Cyperaceae separated from Poaceae about 101.5 million years ago after separated from Ananas comosus in Bromeliaceae about 117.2 million years ago. C. littledalei and C. parvula separated about 5.0 million years ago, after separated from C. kokanica about 6.2 million years ago. In this study, transcriptome data of C. parvula at three different altitudes were also measured and analyzed. Kobresia plants genomes assembly and transcriptome analysis will assist research into mechanisms of plant adaptation to environments with high altitude and cold weather.

Four Pleurotus spp. fungi (P. diamor, P. eryngii, P. sajor-caju, P. citrinopileatus) were compared for their potential to improve nutritional value of corn stover as ruminant feed. Corn stover was inoculated with the fungi under solid-state conditions and their results showed that P. sajor-caju and P. eryngii were better than the other two species of Pleurotus with respect to decreasing the acid detergent lignin (ADL) (8.99 vs 9.88 vs 10.16 vs 10.46). In contrast, P. eryngii had lower ability to degrade cellulose (13.38%). Corn stover treated with P. citrinopileatus had the highest crude protein (CP) content (7.65%), whereas treatment with P. sajor-caju resulted in the highest increase in essential amino acids (55.11%). Although fungal pre-treatment of lignocellulosic biomass does not always result in high-quality feed, overall, P. eryngii and P. sajor-caju improved the nutritive value of corn stover as a ruminant feed.

No abstract