Transcriptome analysis and genome-wide identification of the dehydration-responsive element binding gene family in jackfruit under cold stress.

BACKGROUND: Jackfruit (Artocarpus heterophyllus Lam.) is the world's largest and heaviest fruit and adapts to hot, humid tropical climates. Low-temperature injury in winter is a primary abiotic stress, which affects jackfruit growth and development. Therefore, breeding cold-resistant varieties and identifying the vital genes in the process of cold resistance are essential. The dehydration-responsive element binding (DREB) gene family is among the subfamily of the APETALA2/ethylene response factor transcription factor family and is significant in plant abiotic stress responses. METHODS: In this study, a comparative analysis of the cold resistance property of 'GuangXi' ('GX') and 'Thailand' ('THA') jackfruit strains with different cold resistance characteristics was performed through chlorophyll fluorescence and transcriptome sequencing. RESULTS: We found that differentially expressed genes (DEGs) are significantly enriched in the metabolic processes. Here, 93 DREB genes were identified in the jackfruit genome, and phylogenetic analysis was used to classify them into seven groups. Gene structure, conserved motifs, chromosomal location, and homologous relationships were used to analyze the structural characteristics of the DREB family. Transcriptomics indicated that most of the AhDREB genes exhibited down-regulated expression in 'THA.' The DEGs AhDREB12, AhDREB21, AhDREB29, and AhDREB34 were selected for quantitative real-time PCR, and the results showed that these genes also had down-regulated expression in 'THA.' CONCLUSIONS: The above results suggest the significance of the DREB family in improving the cold resistance property of 'GX.'

The complete chloroplast genome sequence of Mangifera sylvatica Roxb. (Anacardiaceae) and its phylogenetic analysis.

In this study, we firstly reported the complete chloroplast (cp) genome sequences of the Mangifera sylvatica from Nanning, Guangxi province, China. The complete wild mango cp genome size is 158063 bp with a typical small single-copy region (SSC, 18340 bp), a large single-copy region (LSC, 87008 bp) and a pair of inverted repeats (IRs, 26379 bp and 26379 bp respectively). Out of 112 unique annotated genes in mango cp genome, 78 found to be protein coding, 30 to be tRNA and 4 rRNA genes. Besides, we found 51 microsatellite sequences (SSRs) in the cp genome. Sequence alignment and ML analysis of 29 full plastome data revealed M. sylvatica shares the closest relationship with cultivated mango (M. indica) and form a sister group with Rhus chinensis within Anacardiaceae.

[Primary study on rapid propagation of Curcuma xanthorrhiza].

Using the rhizome of Curcuma xanthorrhiza Roxb. as explant to induce the adventitious bud, multiplication and radication. The results showed that the inducing and differentiating of bud was better on MS + 6-BA 1.0 mg/L + NAA 0.5 mg/L, the multiplication of bud was on MS+6-BA 1.2 mg/L + NAA 0.l mg/L and the redication was on 1/2 MS + NAA 0.5 mg/L.