Chicory capable of synthesizing long-chain inulin is of great interest. During the growing season, the sucrose-sucrose 1-fructosyltransferase (1-SST) activity is vital for production of long-chain inulin in chicory. With the purpose to increase inulin chain length, we employed -mediated transformation method. Transgenic chicory plants ( L. var. ) cv. 'Melci' has been developed to overexpress sucrose-sucrose 1-fructosyltransferase (1-SST) under the control of the CaMV 35S promoter. The integration of the T-DNA into the plant genome was confirmed by PCR on genomic DNA using gene-specific primers. Quantification of the 1-SST transcript expression level revealed that transgenic plants showed higher 1-SST expression than those in non-transgenic plants. Further analyses proved that the fructan content of the roots significantly increased in the transgenic plants. These results revealed that overexpression of the, the key gene in inulin biosynthesis in chicory, might serve as a novel approach to develop plants with the long-chain inulin content.

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Sugarcane is an important industrial plant which cultivated in the most arid and semiarid regions. Due to climate change and anthropogenic activities, the sugarcane field damage due to salt deposition and the cultivation of sugarcane has been posed a major threat in the region. To address this issue, the identification of salinity tolerant cultivars would be a suitable strategy to minimize yield loss in the area. MicroRNAs (miRNAs) play important roles in regulating gene expression. The monitoring of the expression of miRNAs and their targeted genes could provide deeper insight into the molecular stress mechanism and screen tolerant cultivars. Our aim was to assess the expression of nine candidate miRNAs and their corresponding targeted genes among the studied sugarcane cultivars under salinity condition, leading to identify the salt-tolerant cultivar. To achieve our goal, a two-factorial experiment with three sugarcane cultivars (CP-48, CP-57, CP-69) and two salinity levels (0 and 8 ds/m) was conducted. One-way ANOVA indicated that there was a significant difference between miRNAs and targeted gene expression. The highest reduction of miRNAs expression was occurred in miR160 while the lower one was happening in miR1432. The data also indicated that the higher and the lowest of targeted genes were in miR160 and miR393 respectively. Among studied cultivars, the CP-57 showed poor performance while CP-69 expresses a superior tolerance to salt stress. Taken together, these results suggested that the screening of well adapted cultivars under salt conditions would be appropriate solutions to combat salinity stress in saline lands.