文献类型： 外文期刊

作者： Fan, Z-W ¹ ; Buschmann, H. ² ; Sauerborn, J. ² ;

作者机构： 1.Chinese Acad Trop Agr Sci, Environm & Plant Protect Inst, Danzhou 571737, Hainan, Peoples R China

2.Chinese Acad Trop Agr Sci, Environm & Plant Protect Inst, Danzhou 571737, Hainan, Peoples R China; Univ Hohenheim, Inst Plant Prod & Agroecol Trop & Subtrop, D-7000 Stuttgart, Germany

关键词： induced resistance;prohexadione-calcium;seed germination;phenolic compounds

期刊名称：WEED RESEARCH （ 影响因子：2.424； 五年影响因子：2.533 ）

ISSN： 0043-1737

年卷期： 2007 年 47 卷 1 期

页码：

收录情况： SCI

摘要： Prohexadione-calcium (PHDC) is a plant growth retardant that inhibits gibberellin biosynthesis and transiently alters the spectrum of flavonoids and their phenolic precursors. In this study, root chamber and pot experiments were conducted to evaluate the effects of PHDC on Orobanche cumana seed germination and induction of sunflower resistance to this root parasitic weed. Root chamber experiments indicated that PHDC did not interfere with the progress of Orobanche seed germination, but retarded O. cumana tubercle formation and development. In pot experiments, control of O. cumana by PHDC depended on its dose, method of application and sunflower cultivar. In sunflower cv. HA89, PHDC at 10 mg LS-1 (litre soil) as two drenches or at 1 mM as two foliar sprays significantly reduced the total number and dry matter of O. cumana without influencing flower, leaf and root development. In sunflower cv. Albena, PHDC at 20 and 30 mg LS-1, but not at 10 mg LS-1, as two drenches significantly reduced O. cumana infection. Sunflower cv. HA89 was less susceptible to O. cumana and more inducible by PHDC than sunflower cv. Albena. The biochemical analysis of root extracts revealed a significantly higher accumulation of free phenolics in sunflower cv. HA89 after PHDC soil drench, but not in Albena. No significant lignification was observed after PHDC treatments. The results suggest that PHDC reduces O. cumana infection in sunflower by inducing host resistance, not by directly interfering with the parasite. Free phenolics play an important role in sunflower response to the parasite.