Isolation and identification of core-genes in barley roots under low phosphorus stress.

Background: Low phosphorus stress significantly limits plant growth and agricultural production. Identifying core genes responsive to low-phosphorus stress and breeding new high-phosphorus-efficient crop varieties are crucial for solving practical production problems. Barley is an important crop with genetic diversity and stress tolerance. In this study, we aimed to explore the core genes in barley roots under low-phosphorus stress.

Methods and results: Based on the transcriptome sequencing data of barley root under low phosphorus stress, we used the Weighted Gene Co-expression Network Analysis (WGCNA) method on the high phosphorus-efficient genotype GN121. All expressed genes related to phosphorus content were grouped into 16 co-expression modules. Six highly correlated modules were selected for GO enrichment analysis. Genes in the green module were significantly enriched in "response to stress" and "response to oxidative stress" signaling pathways, while genes in the turquoise module were significantly enriched in "cell response to stimulation" and "cell response to stress" pathways. Through further analysis of these two modules, we identified three core genes: endoglucan-1,3-β-glucosidase 3 (HORVU2Hr1G044440) and peroxidase 5 (HORVU1Hr1G023750 and HORVU1Hr1G016820).

Conclusions: The identified three core genes above mentioned are involved in the regulation of abiotic stress. These results offer clues for further research on the molecular mechanism of barley's response to low phosphorus stress and genetic resources for breeding high-phosphorus-efficient crop varieties. The findings contribute to understanding how barley adapts to low-phosphorus environments and provide a basis for improving crop phosphorus-use efficiency.