论文部分内容阅读
【目的】探究咯菌腈对牡丹黑斑病菌(Alternaria suffruticosae)、黄斑病菌(Phyllosticta commonsii)、腔孢叶斑病菌(Hainesia lythri)和叶霉病菌(Cladosporium paeoniae)菌丝生长、孢子萌发、芽管伸长及产孢的抑制活性,分析咯菌腈在牡丹病害化学防治上的应用前景。【方法】采用菌丝生长速率法测定咯菌腈对菌丝生长的抑制活性,采用涂布平板法测定咯菌腈对孢子萌发、产孢时间及产孢量、芽管伸长及芽管和孢子形态的影响。【结果】咯菌腈对腔孢叶斑病菌菌丝生长的抑制作用最强,EC_(50)为0.01μg·mL~(-1),其次为黑斑病菌和黄斑病菌,分别为0.07和0.35μg·mL~(-1);咯菌腈对4种病菌的孢子萌发均有较强的抑制作用,对腔孢叶斑病菌的抑制作用最强,其EC_(50)为1.26μg·mL~(-1),对其他3种病菌孢子萌发的EC_(50)在3.27—3.45μg·mL~(-1);0.1μg·mL~(-1)咯菌腈对4种病菌分生孢子芽管伸长的抑制率在40%—70%,表明咯菌腈对4种病菌分生孢子芽管伸长均有明显的抑制作用,浓度越大抑制作用越强,各浓度间差异显著,其中对腔孢叶斑病菌芽管伸长抑制的EC_(50)为0.04μg·mL~(-1),抑制作用最强,对其他3种病菌芽管伸长的EC_(50)在0.08—0.22μg·mL~(-1);咯菌腈对黑斑病菌和黄斑病菌分生孢子和芽管的致畸作用强烈,可导致孢子及芽管膨大、过度分枝,而对叶霉病菌和腔孢叶斑病菌致畸作用较弱,芽管及孢子形态基本正常;咯菌腈可推迟黑斑病菌、黄斑病菌及叶霉病菌的产孢时间,对黑斑病菌产孢量的抑制作用最强,EC_(50)为0.05μg·mL~(-1),对叶霉病菌次之,EC_(50)为0.38μg·mL~(-1),但对腔孢叶斑病菌产孢有促进作用。【结论】咯菌腈对牡丹黑斑病菌及腔孢叶斑病菌的菌丝生长、孢子萌发及芽管伸长均有很强的抑制作用,但对腔孢叶斑产孢具有一定的促进作用;对叶霉病菌和黄斑病菌孢子萌发及芽管伸长、黄斑病菌菌丝生长及叶霉病菌产孢的抑制作用强烈;由于咯菌腈内吸活性较弱,无法抑制已侵入牡丹叶片的病原真菌的生长,故建议作为保护剂在病害发生前施用。
【Objective】 The objective of this study was to investigate the effects of fludioxonil treatment on the mycelial growth, spore germination, germ tube formation and growth of Alternaria suffruticosae, Phyllosticta commonsii, Hainesia lythri and Cladosporium paeoniae. Elongation and sporulation inhibitory activity, analysis of fludioxonil in peony disease chemical control of the application prospects. 【Method】 The inhibitory activity of fludioxonil on mycelial growth was measured by mycelial growth rate method. The spore germination, sporulation time, sporulation rate, germination tube elongation and germination of fluconazole Effect of spore morphology. 【Results】 Fludioxonil had the strongest inhibitory effect on the mycelium growth of Alternaria oryzae with an EC50 of 0.01 μg · mL -1 followed by Alternaria and Maclekopsis, which were 0.07 and 0.35 μg · mL -1. Fludioxonil inhibited the spore germination of the four pathogenic bacteria and had the strongest inhibitory effect on the leaf spore germ, with EC 50 of 1.26 μg · mL -1. (-1). The EC50 of spore germination of the other three pathogens was between 3.27-3.45μg · mL -1 and 0.1μg · mL -1. The inhibitory rate of tube elongation was 40% -70%, indicating that fludioxonil significantly inhibited the germination of the spores of the four pathogenic bacteria. The higher the concentration, the greater the inhibitory effect, with significant differences among the concentrations The EC50 of germ tube of Streptoverticillium spp. Was 0.04 μg · mL -1, the strongest inhibitory effect was on EC 50 of germination of germ tube of Alternaria solani at 0.08-0.22 μg · mL -1. Fludioxonil had a strong teratogenicity on the conidia and germ tube of Alternaria and Fusarium solani, which resulted in enlargement and over-branching of spores and germ tube, Spore leaf spot germicidal effect is weak, germ tube and spore morphology is basically normal; fludioxonil can push Alternaria alternata, Fusarium oxysporum and Fusarium solani had the strongest inhibitory effect on sporulation of Alternaria. EC50 was 0.05 μg · mL -1, followed by Fusarium solani, EC50 (50) was 0.38μg · mL ~ (-1), but could promote the sporulation of Cymbidium vaccae. 【Conclusion】 Fludioxonil has a strong inhibitory effect on mycelial growth, spore germination and germ tube elongation of Alternanthera philoxeroides and Alternaria brassicae, ; On the leaf mold fungus and mackerelospores germination and germination tube elongation, mycelium growth and leaf mold fungus sporulation of the strong inhibition; due to fluconazole internal absorption activity is weak, can not inhibit the pathogen has invaded the leaves of peonies Fungal growth, it is recommended as a protective agent in the disease before the application.