Journal of Integrative Agriculture ›› 2017, Vol. 16 ›› Issue (09): 1956-1967.DOI: 10.1016/S2095-3119(16)61618-0

• 论文 • 上一篇    下一篇

DOU Jun-ling, YUAN Ping-li, ZHAO Sheng-jie, HE Nan, ZHU Hong-ju, GAO Lei, JI Wan-li, LU Xuqiang, LIU Wen-ge   

  • 收稿日期:2016-11-01 出版日期:2017-09-20 发布日期:2017-09-05

Effect of ploidy level on expression of lycopene biosynthesis genes and accumulation of phytohormones during watermelon (Citrullus lanatus) fruit development and ripening

DOU Jun-ling1, 2, YUAN Ping-li1, ZHAO Sheng-jie1, HE Nan1, ZHU Hong-ju1, 2, GAO Lei1, JI Wan-li1, LU Xu-qiang1, LIU Wen-ge1   

  1. 1 Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou 450009, P.R.China
    2 College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, P.R.China
  • Received:2016-11-01 Online:2017-09-20 Published:2017-09-05
  • Contact: Correspondence LU Xu-qiang, E-mail: luxuqiang123@163.com; LIU Wen-ge, Tel: +86-371-65330936, E-mail: lwgwm@163.com
  • About author:DOU Jun-ling, E-mail: junlingdou@163.com
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (31171979 and 31471893), the Agricultural Science and Technology Innovation Program, China (ASTIP) (CAAS-ASTIP-2017-ZFRI), the earmarked fund for the China Agriculture Research System (CARS-26-03), and the Central Public-interest Scientific Institution Basal Research Fund, China (1610192016301 and 1616032017209).

Abstract: The difference between lycopene and phytohormone levels among diploid, triploid and tetraploid plants of two watermelon cultivars during fruit growth and ripening was studied.  The expression pattern of five genes (phytoene synthase (PSY1), phytoene desaturase (PDS), ζ-carotene desaturase (ZDS), carotenoid isomerase (CRTISO), and lycopene β-cyclase (LCYB)) was analyzed in details.  In red-fleshed cultivar Mimei, lycopene content increased rapidly from 25 to 35 days after pollination (DAP), and then decreased at 40 DAP.  Triploid and tetraploid fruit had higher levels of lycopene than diploid.  Moreover, triploid tended to contain more lycopene than tetraploid during fruit growth and ripening stages.  However, little amount of lycopene (0–2 mg kg–1 fresh weight (FW)) in yellow-fleshed cultivar Huangmei was found during all fruit development stages.  In Mimei, transcript level of PSY1 was generally higher than the other four genes, and LCYB gene expression was the lowest among all five genes being tested.  PSY1, CRTISO and LCYB genes showed higher transcript levels in polyploid than in diploid fruit.  By contrast, in Huangmei, transcript level of LCYB was not the lowest, but only lower than that of PSY1PSY1, CRTISO and LCYB genes showed higher expression levels in diploid than in polyploid fruit.  In Mimei, the negative correlation between gibberellane (GA) content and lycopene accumulation was determined in all three different ploidy fruits, while a positive correlation was observed between abscisic acid (ABA) content and lycopene accumulation only in diploid watermelon.  These results indicated that different lycopene contents in different ploidy watermelons is regulated by the differential transcription expression of the lycopene metabolic genes and phytohormones. 

Key words: watermelon ,  lycopene , gene expression , ploid , flesh color ,  phytohormone