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Ziziphus jujuba is one of the most important and widely grown fruits in China. Jujube witches' broom (JWB), an important disease in Z. jujube, could cause heavy loss for its industry. The disease is associated with the presence of ‘Candidatus Phytoplasma ziziphi’, a prokaryote, and very little knowledge is known about its interactions with jujube plants. Therefore, in the present study cDNA samples from healthy and diseased plants were sequenced on Illumina HISeq2000 and gene expression and metabolism regulation were compared. In the two libraries obtained from the leaves, 4266 differentially expressed genes (DEGs) were identified. Among them, 2070 genes were upregulated, and 2196 genes were downregulated. The comparison between the libraries from flowers showed 3800 DEGs, with 1965 upregulated and 1835 down-regulated genes. Among all these some specific genes were identified to be functionally related to the amino acid metabolism and the carotenoid pathway, which may be related to the lack of nutrition and the main symptoms of yellowing, brooming and small leaves. The results of this work provides a valuable resource for further studies of the disease on genetic and molecular levels.

Lily is a well-known ornamental plant with a diversity of fragrant types. Basic information on lily floral scent compounds has been obtained for only a few accessions, and little is known aboutLiliumaroma types, the terpene synthase genes that may play roles in the production of key volatiles, or the range of monoterpenes that these genes produce. In this study, 41 cultivars were analyzed for volatile emissions, and a total of 46 individual volatile compounds were identified, 16 for the first time in lilies. Lily accessions were classified into six groups according to the composition of major scent components: faint-scented, cool, fruity, musky, fruity-honey, and lily. Monoterpenes were one of the main groups of volatiles identified, and attention was focused on terpene synthase (TPS) genes, which encode enzymes that catalyze the last steps in monoterpene synthesis. Thirty-two candidate monoterpene synthase cDNAs were obtained from 66 lily cultivars, and 64 SNPs were identified. Two InDels were also shown to result from variable splicing, and sequence analysis suggested that different transcripts arose from the same gene. All identified nucleotide substitution sites were highly correlated with the amounts of myrcene emitted, and InDel site 230 was highly correlated with the emission of all major monoterpenoid components, especially (E)-β-ocimene. Heterologous expression of five cDNAs cloned from faint-scented and strong-scented lilies showed that their corresponding enzymes could convert geranyl diphosphate to (E)-β-ocimene,α-pinene, and limonene. The findings from this study provide a major resource for the assessment of lily scent volatiles and will be helpful in breeding of improved volatile components.

Jujube witches’ broom disease caused devastating damages in some Chinese orchards. To study this disease, transcriptome sequencing was used for obtaining information on gene expression that can greatly facilitate studies of this plant species for which a sequenced genome is not available. In the present study 45,132 unigenes were identified from contigs dataset, and functional annotation was carried out in different systems. The results show the presence of some pathogenesis related pathways in jujube during phytoplasma infection.