Effects of Hexaconazole on Growth and Antioxidant Potential of Cucumber Seedlings under UV-B Radiation



Kim, Tae-Yun;Hong, Jung-Hee

  • 투고 : 2012.08.28
  • 심사 : 2012.12.10
  • 발행 : 2012.12.31


The present study was conducted to determine the effect of hexaconazole (HEX), a triazole fungicide, on the growth, yield, photosynthetic response and antioxidant potential in cucumber (Cucumis sativus L.) plants subjected to UV-B stress. UV-B radiation and HEX were applied separately or in combination to cucumber seedlings. The growth parameters were significantly reduced under UV-B treatment, however, this growth inhibition was less in HEX treated plants. HEX caused noticeable changes in plant morphology such as reduced shoot length and leaf area, and increased leaf thickness. HEX was quite persistent in inhibiting shoot growth by causing a reduction in shoot fresh and dry weight. HEX noticeably recovered the UV-B induced inhibition of biomass production. Significant accumutation in anthocyanin and flavonoid pigments in the leaves occurred as a result of HEX or UV-B treatments. HEX permitted the survival of more green leaf tissue preventing chlorophyll content reduction and higher quantum yield for photosystemII under UV-B exposure. HEX treatment induced a transient rise in ABA levels in the leaves, and combined application of HEX and UV-B showed a significant enhancement of ABA content which activates $H_2O_2$ generation. UV-B exposure induced accumulation of $H_2O_2$ in the leaves, while HEX prevented UV-B induced increase in $H_2O_2$, indicating that HEX serves as an antioxidant agent able to scavenge $H_2O$ to protect cells from oxidative damage. An increase in the ascorbic acid was observed in the HEX treated cucumber leaves affecting many enzyme activities by removing $H_2O_2$ during photosynthetic processes. The activities of antioxidant enzymes including catalase(CAT), ascorbate peroxidase(APX), superoxide dismutase(SOD) and peroxidase(POD) in the leaves in the presence of HEX under UV-B stress were higher than those under UV-B stress alone. These findings suggest that HEX may participate in the enhanced tolerance to oxidative stress. From these results it can be concluded that HEX moderately ameliolate the effect of UV-B stress in cucumber by improving the components of antioxidant defense system.


Antioxidative enzymes;Cucumber;Hexaconazole;Photosynthetic pigments;UV-B


  1. Abbas, S., Zaidi, P. H., 1997, Chemical manipulation through triadimefon against ultaviolet-B induction induced injury to membrane components of Cicer arietinum L., Plant Physiol. Biochem., 24, 64-66.
  2. Asare-Boamah, N. K., Hofstra, G., Fletcher, R. A., Dumbroff, E. B., 1986, Triadimefon protects bean plants from water stress through its effects on abscisic acid, Plant Cell Physiol., 27, 383-390.
  3. Berova, M., Zlatev, Z., Stoeva, N., 2002, Effect of paclobutrazol on wheat seedlings under low temperature stress, Bulg. J. Plant Physiol., 28, 75-84.
  4. Burrows, G. E., Boag, T. S., Stewart, W. P., 1992, Changes in leaf, stem and root anatomy of Chrysanthemum cv. Lillian Hoek following paclobutrazol application, J. Plant Growth Regul., 11, 189-194.
  5. Caldwell, M. M., Teramura, A. H., Tevini, M., Bornman, J. F., Bj"orn, I. O., Kulandaivelu, G., 1995, Effects of increased solar ultraviolet radiation on terrestrial plants, Ambio., 24, 166-173.
  6. Chen, G. X., Asada, K., 1989, Ascorbate peroxidase in tea leaves : Occurrence of two isozymes and the differences in their enzymatic and molecular properties, Plant Cell Physiol., 30, 987-998.
  7. Durner, J., Klessig, D. F., 1996, Salicylic acid is a modulator of tobacco and mammalian catalases, J. Biol. Chem., 271, 28492-28502. https://doi.org/10.1074/jbc.271.45.28492
  8. Feng, Z., Guo, A., Feng, Z., 2003, Amelioration of chilling stress by triadimefon in cucumber seedlings, Plant Growth Regul., 39, 277-283. https://doi.org/10.1023/A:1022881628305
  9. Fletcher, R. A., Gilley, A., Sankhla, N., Davis, T. D., 2000, Triazoles as plant growth regulators and stress protectants, Hort. Rev., 24, 55-138.
  10. Foyer, C. H., Noctor, G., 2003, Redox sensing and signaling associated with reactive oxygen in chloroplasts, peroxisomes and mitochondria, Physiol. Plant., 119, 355-364. https://doi.org/10.1034/j.1399-3054.2003.00223.x
  11. Frohnmeyer, H., Staiger, D., 2003, Ultraviolet-B radiation responses in plants : Balancing damage and protection, Plant Physiol., 133, 1420-1428. https://doi.org/10.1104/pp.103.030049
  12. Gopi, R., Jaleel, C. A., Sairam, R., Lakshmanan, G. M. A., Gomathinayagam, M., Panneerselvam, R., 2007, Differential effects of hexaconazole and paclobutrazol on biomass, electrolyte leakage, lipid peroxidation and antioxidant potential of Daucus carota L., Colloids Surf. B:Biointerf., 60, 180-186. https://doi.org/10.1016/j.colsurfb.2007.06.003
  13. Inskeep, W. P., Bloom, P. R., 1985, Extinction coefficients of chlorophyll a and b in N, N-dimethylformamide and 80% acetone, Plant Physiol., 77, 483-485. https://doi.org/10.1104/pp.77.2.483
  14. Jain, S. K., Singh, R., Misra, K. K., 2002, Effect of paclobutrazol on growth yield and fruit quality of lemon (Citrus limon), Indian J. Agric. Sci., 72, 488-489.
  15. Jaleel, C. A., Gopi, R., Lakshmanan, A. G. M., Panneerselvam, R., 2006, TDM induced changes in the antioxidant metabolism and ajmalicine production in Catharanthus roseus (L.) G. Don., Plant Sci., 171, 271-276. https://doi.org/10.1016/j.plantsci.2006.03.018
  16. Jaleel, C. A., Gopi, R., Manivannan, P., Panneerselvam, R., 2007a, Responses of antioxidant defense system of Catharanthus roseus (L.) G. Don. to paclobutrazol treatment under salinity, Acta Physiol. Plant., 29, 205-209. https://doi.org/10.1007/s11738-007-0025-6
  17. Jaleel, C. A., Kishorekumar, A., Manivannan, P., Sankar, B., Gomathinayagam, M., Gopi, R., Somasundaram, R., Panneerselvam, R., 2007b, Alterations in carbohydrate metabolism and enhancement in tuber production in white yam (Dioscorea rotundata Poir) under triadimefon and hexaconazole applications, J. Plant Growth Regul., 53, 7-16. https://doi.org/10.1007/s10725-007-9198-7
  18. Jansen, M. A. K., 2002, Ultraviot-B radiation effects on plants : Induction of morphogenic responses, Physiol. Plant., 116, 423-429. https://doi.org/10.1034/j.1399-3054.2002.1160319.x
  19. Jiang, Y., Joyce, D. C., 2003, ABA effects on ethylene production, PAL activity, anthocyanin and phenolic contents of strawberry fruit, Plant Growth Regul., 39, 171-174. https://doi.org/10.1023/A:1022539901044
  20. Johnson, I., Marimuthu, T., Samiyappan, R., Cha, B., 2008, Influence of hexaconazole on biochemieal constituents of groundnut, Kor. J. Pesticide Sci., 12, 335-341.
  21. Kondo, N., Kawashima, M., 2000, Enhancement of the tolerance of oxidative stress in cucumber (Cucumis sativus L.) seedlings by UV-B irradiation : Possible involvement of phenolic compounds and antioxidative enzymes, J. Plant Res., 113, 311-317. https://doi.org/10.1007/PL00013863
  22. Kraus, T. E., Evans, R. C., Fletcher, R. A., Pauls, K .P., 1995, Paclobutrazol enhances tolerance to increased levels of UV-B radiation in soybean (Glycine max) seedlings, Can. J. Bot., 73, 797-806. https://doi.org/10.1139/b95-088
  23. Lakshmanan, G. M. A., Jaleel, C. A., Gomathinayagam, M., Panneerselvam, R., 2007, Changes in antioxidant potential and sink-organ dry matter with pigment accumulation induced by hexaconazole in Plectranthus forskholii Briq, C.R. Biologies, 330, 814-820. https://doi.org/10.1016/j.crvi.2007.08.008
  24. Larkindale, J., Knight, M. R., 2002, Protection against heat stress-induced oxidative damage in Arabidopsis involves calcium, abscisic acid, ethylene and salicylic acid, Plant Physiol., 128, 682-695. https://doi.org/10.1104/pp.010320
  25. Li, C., Puhakainen, T., Welling, A., Vihera-Aarnio, A., Ernstsen, A., Junttila, O., Heino, P., Palva, E. T., 2002, Cold acclimation in silver birch (Betula pendula) development of freezing tolerance in different tissues and climatic ecotypes, Physiol. Plant., 116, 478-488. https://doi.org/10.1034/j.1399-3054.2002.1160406.x
  26. Manivannan, P., Jaleel, C. A., Kishorekumar, A., Sankar, B., 2008, Protection of Vigna unguicula (L.) Walp. plants from salt stress by paclobutrazol, Colloids Surf. B:Biointerf., 61, 315-318. https://doi.org/10.1016/j.colsurfb.2007.09.007
  27. Manivannan, P., Jaleel, C. A., Kishorekumar, A., Sankar, B., Somasundaram, R., Sridharan, R., Panneerselvam, R., 2007, Propiconazole induced changes in antioxidant metabolism and drought stress amelioration in Vigna unguiculata (L.) Walp. by hexaconazole under water deficit stress, Colloids Surf. B: Biointerf., 57, 69-74. https://doi.org/10.1016/j.colsurfb.2007.01.004
  28. Mark, U., Tevini, M., 1997, Effects of solar ultraviolet-B radiation, temperature and $CO_2$ on growth and physiology of sunflower and maize seedlings, Plant Ecology, 128, 225-234. https://doi.org/10.1023/A:1009798528605
  29. Mirecki, R. M., Teramura, A. H., 1984, Effects of ultraviolet- B irradiation on soybean, Plant Physiol, 74, 475-480. https://doi.org/10.1104/pp.74.3.475
  30. Polle, A., Otter, T., Seifert, F., 1994, Apoplastic peroxidases and lignifications in needles of Norway spruce (Picea abies L.), Plant Physiol., 106, 53-60. https://doi.org/10.1104/pp.106.1.53
  31. Sankar, B., Jaleel, C. A., Manivannan, P., Kishorekumar, A., Somasundaram, R., Panneerselvam, R., 2007, Effect of paclobutrazol on water stress amelioration through antioxidants and free radical scavenging enzymes in Arachis hypogaea L., Colloids Surf. B:Biointerf., 57, 123-134.
  32. Schreiber, U., Schliwa, U., Bilger, W., 1986, Continuous recording of photochemical and nonphotochemical chlorophyll fluorescence quencing with a new type of modulation fluorometer, photosynth. Res., 10, 51-62. https://doi.org/10.1007/BF00024185
  33. Singh, R., Thakore, B. B. L., 1998, Effect of hexaconazole on chlorophyll and NPK contents of bottlegourd leaves, Indian J. Mycol. Plant Pathol., 28, 216-217.
  34. Spychalla, J. P., Desborough, S. L., 1990, Superoxide dismutase, catalase and alpha tocopherol content of stored potato tubers, Plant Physiol., 94, 1214-1218. https://doi.org/10.1104/pp.94.3.1214
  35. Tattini, M., Galardi, C., Pinelli, P., Massai, R., Remorini, D., Agati, G., 2004, Differential accumulation of flavonoids and hydroxycinnainates in leaves of Ligustrum vulare under excess light and drought stress, New Phytol., 163, 547-561. https://doi.org/10.1111/j.1469-8137.2004.01126.x
  36. Tonkinson, C. L., Lyndon, R. L., Arnold, G. M., Lenton, J. R., 1995, Effect of Rht 13 dwarfing gene on dynamics of cell expansion in wheat leaves, and it's modification by gibberellic acid and paclobutrazol, J. Exp. Bot., 46, 1085-1092. https://doi.org/10.1093/jxb/46.9.1085
  37. Veljovic-Jovanovic, S., Noctor, G., Foyer, C. H., 2002, Are leaf hydrogen peroxide concentration commonly overestimated? The potential influence of artefactual interference by tissue phenolics and ascorbate, Plant Physiol. Biochem., 40, 501-507. https://doi.org/10.1016/S0981-9428(02)01417-1
  38. Walker, M. A., McKersie, B. D., 1993, Role of ascorbateglutathione antioxidant system in chilling resistance of tomato, J. Plant Physiol., 141, 234-239. https://doi.org/10.1016/S0176-1617(11)80766-2
  39. Kishorekumar, A., Jaleel, C. A., Manivannan, P., Sankar, B., Sridharan, R., Panneerselvam, R., 2007, Comparative effects of different triazole compounds on growth, photosynthetic pigments and carbohydrate metabolism of Solenostemon rotundifolius, Colloids Surf. B: Biointerf., 60, 207-212. https://doi.org/10.1016/j.colsurfb.2007.06.008


연구 과제 주관 기관 : Pusan National University