Transcriptome Analysis of Embryogenic and Non-Embryogenic Callus of Picea Mongolica

Picea mongolica is a rare tree species in China, which of great significance combating desertification and improving the harsh ecological environment. Due to low rate natural regeneration, high mortality, susceptibility pests cold springs, has gradually become extinct. At present, somatic embryogenesis (SE) most effective method micro-proliferation conifers, but induction embryogenic callus (EC) low, EC difficult differentiate from non-embryonic (NEC). Therefore, NEC were compared morphology, histological, physiological, transcriptional levels, respectively. Morphological observation showed that was white transparent filamentous, while compact brownish-brown lumpy. Histological analyses cells large loosely arranged; nuclei attached edge small; cytoplasm low; cell gap irregular. In EC, small cells, closely arranged nucleus nucleolus observed. Physiological studies significant differences ROS-scavenging enzymes between NEC. Transcriptome profiling revealed 13,267 differentially expressed genes (DEGs) identified, 3682 up-regulated, 9585 down-regulated. total, 63 GO terms had enrichment, 32 DEGs plant hormone signal transduction pathway 502 different transcription factors (TFs) characterized into 38 TF families. Meanwhile, we identified gene expression trends associated with embryo development hormones (AUX/IAA, YUCCA, LEA, etc.), stress (GST, HSP, GLP, phenylpropanoid metabolism (4CL, HCT, PAL, (AP2/ERF, MYB, WOX, etc.). addition, nine chosen for RT-qPCR, results consistent RNA-Seq data. This study changes histology, physiology, differentiation laid foundation finding key promote formation.