羧基化壳寡糖络合碘(CCOS-I)对水稻纹枯病菌的抑制作用及机理初讨

The Effect of Chitosan Oligosaccharide Complex Iodine(CCOS-I) on the Inhibition of Rice Rhizoctonia solani and the Effect of Defense Enzyme Activity Inhibitory

为明确羧基化壳寡糖络合碘(CCOS-I)对水稻纹枯病的防治作用,以20%井冈霉素可湿性粉剂为对照药剂,测定CCOS-I对水稻纹枯病菌的室内抑菌效果和田间防效,以及对超氧化物歧化酶(superoxidedismutase,SOD)、叶片过氧化物酶(peroridase,POD)、多酚氧化酶(polyphenol oxidase,PPO)、苯丙氨酸解氨酶(phenylalanine ammonia-lyase,PAL)和β-1,3-葡聚糖酶(β-1,3-glucanase)等相关防御酶活性的影响。结果表明:羧基化壳寡糖络合碘对该病菌抑制效果明显,经室内毒力测定,其EC50值12.22 mg/L,明显高于对照药剂20%井冈霉素粉剂。田间药效试验结果表明,在水稻第3次用药后14d,100g/hm2的羧基化壳寡糖络合碘防效达到80.66%,与井冈霉素有效剂量150 g/hm2的效果相当,优于同剂量井冈霉素处理。CCOS-I在试验剂量范围内对水稻纹枯病有很好的防治作用,且对水稻生长无任何药害现在发生,可以诱导水稻相关防御酶活性提高,适用于水稻纹枯病的防治,具有一定的开发推广价值。

In order to clarify the preventive and therapeutic effects on rice sheath blight, 20% validamycin wettable powder as the control, the antibacterial effect of carboxylated chitosan oligosaccharide iodine complex（CCOS-I） on R.solani in a greenhouse and its efficacy in the paddy field were assayed. And the induced activity of CCOS-I on the peroxidase（POD）, superoxide dismutase（SOD）, polyphenol oxidase（PPO）, phenylalnaine ammonia-lyase（PAL） and beta-1,3-glucanase（beta-1,3-glucanase） were studied. CCOS-I had a significant inhibitory effect on R. solani, and its EC50 value was 12.22 mg/L, which was obviously higher than that of the control in the field trial test, The control effect of CCOS-I at the effective dose of 100 g/hm^2 was 80.66%,which was equivalent to the valid dose of validamycin 150 g/hm^2 and better than the same dose of validamycin,after the third spraying 14 d. Compared with the spraying control agent, CCOS-I not only had good control effect on rice sheath blight, but also had a certain promoting effect on rice growth. CCOS-I induced rice resistance against R. solani which related to the increased activities of defense enzymes caused by CCOS-I. CCOS-I was safe for rice and had a certain value of development and promotion.