The full-length transcriptome analysis of blueberry under different pH conditions

The breeding of high soil pH tolerant blueberry cultivars is conducive to their cultivation and can reduce fertility costs. However, the molecular mechanisms of high soil pH tolerance of blueberry cultivars remain unclear. To understand the adaptive response of blueberry varieties to high pH, the full-length transcriptome analysis was performed with Spartan (high pH-soil-sensitive variety) and Reka (high pH-soil-tolerant variety) treated with low and high pH by hydroponics. The nutrient content analysis showed that significant changes in the content of Al, Fe, K, N and P were detected between low and high pH treatments in roots and leaves between two cultivars. Full-length transcriptome analysis found the total 131,143 transcripts were identified through sequencing, in which 18,193 were novel transcripts and 887 lncRNAs were predicted. We identified 1508 up-regulated and 944 down-regulated genes in leaves of Reka under high pH, and 3910 up-regulated and 3853 down-regulated DETs were identified in the root of Reka under high pH. Specifically, we identified 11 Al-responsive genes, seven Fe-responsive genes, 10 P-responsive genes, and two K-responsive genes that displayed differential expression between low and high pH treatments in roots between two cultivars. Meanwhile, weighted gene co-expression network analysis (WGCNA) was used to identify hub gene in each group. The top 30 hub genes were identified in the root and leaves of Reka under high pH, which include two glycosyl hydrolases family, one membrane transport protein, one Polysaccharide biosynthesis, two lipid-transfer protein, one Glycosyl hydrolases family, one Copper binding protein and one AUX/IAA family. These provide a theoretical basis for the mechanism of high pH tolerance in blueberries and varieties developed.