[Show abstract][Hide abstract] ABSTRACT: Background: Plant cell suspension culture of Vitis vinifera is a promising technology for investigating different factors that are able to induce and/or modify stilbenes biosynthesis. Jasmonates have been reported to play an important role in a signal transduction pathway that regulates defence responses as well as the production of secondary metabolites. In this study, 2, 3-dihydroxypropyl jasmonate (DHPJA) was used to investigate its effect on stimulating trans-resveratrol (t-R) accumulation and the plant defence responses in Vitis vinifera cv. Kyoho cell suspension cultures for the first time. Results: It demonstrated that DHPJA had superior effects on stilbenoids accumulation over methyl jasmonate (MeJA). The optimal condition was 150 mu M DHPJA added on day 15 of cultivation period, with the highest level of t-R accumulation which was increased 1.8-fold and 1.3-fold compared with the control and 150 mu M MeJA respectively. DHPJA induced stronger plant defence responses, including oxidative burst and activation of L-phenylalanine ammonia lyase (PAL) than MeJA. H2O2 generation induced by DHPJA played a significant role in enhancing t-R accumulation. Adding a specific inhibitor of H2O2 signalling pathway inhibited DHPJA-induced t-R accumulation, but had no effects on DHPJA-induced other metabolites accumulation, which resulted in regulations of product diversity. Conclusions: This study demonstrated that DHPJA was an efficient elicitor to enhance t-R accumulation by activating stronger oxidative burst, and H2O2 signalling pathway could regulate product diversity in DHPJA-induced V. vinifera cv. Kyoho cell suspension cultures.
[Show abstract][Hide abstract] ABSTRACT: Plant activators are a novel kind of agrochemicals that could induce resistance in many plants against a broad spectrum of diseases. To date, only few plant activators have been commercialized. In order to develop novel plant activators, a series of benzo-1,2,3-thiadiazole-7-carboxylate derivatives were synthesized, and the structures were characterized by (1)H NMR, IR, elemental analyses, and HRMS or MS. Their potential systemic acquired resistance as plant activators was evaluated as well. Most of them showed good activity, especially, fluoro-containing compounds 3d and 3e, which displayed excellent SAR-inducing activity against cucumber Erysiphe cichoracearum and Colletotrichum lagenarium in assay screening. Field test results illustrated that compounds 3d and 3e were more potent than the commercial plant activator, S-methyl benzo[1,2,3]thiadiazole-7-carbothioate (BTH) toward these pathogens. Further, the preparation of compound 3d is more facile than BTH with lower cost, which will be helpful for further applications in agricultural plant protection.
No preview · Article · Dec 2011 · Journal of Agricultural and Food Chemistry
[Show abstract][Hide abstract] ABSTRACT: Based on the hypoxia prodrug moiety of p-nitrobenzyl, a selective ratiometric fluorescent sensor (RHP) for the detection of microenvironment hypoxia was designed and synthesized. RHP can be selectively activated by bioreductive enzymes (NTR) and results in an evident blue to green fluorescent emission wavelength change in both solution phases and in cell lines, which might be the first fluorescent ratiometric probe for hypoxia in solid tumors.