Physiological and transcriptional responses of Phalaris arundinacea under waterlogging conditions

Abstract As a high-yielding forage grass, Phalaris arundinacea is widely distributed in the Qinghai-Tibet Plateau region of China. To explore physiological and molecular response mechanisms of Phalaris arundinacea under waterlogging, we analyzed the biomass, photosynthetic parameters, and physiological indexes of three locally grown subspecies under 10 cm submersion. The material Z0611 showed the strongest waterlogging resistance, while YS showed the weakest performance. Transcriptome sequencing analysis demonstrated that YS and Z0611 had 17,010 and 7,566 differentially expressed genes (DEGs), respectively, which were mainly concentrated in the metabolic process, cell, ribosome, and phenylpropanoid biosynthesis pathway in GO and KEGG databases. We also identified a large number of genes involved in carbohydrate metabolism, hormone signaling regulation, transcription factors, antioxidant system, and ethylene signaling. Our research may provide a scientific basis for the restoration of wetland environment on the Qinghai-Tibet Plateau, and lay a foundation for further study of the waterlogging resistance genes of Phalaris arundinacea and breeding of new strains resistant to waterlogging stress.