Study On Fumigant Activity Of Several Horseradish Compounds And Investigation On Optimization Of EITC

Allyl isothiocyanate which is active ingredient of horseradish to storage pests, soil-borne plant pathogenic fungi and nematodes is very strong. In this paper, the biological fumigation activity of 10 kinds of compounds on the storage pests, soil-borne pathogenic fungi, Meloidogyne incognita were measured, the results show that:1, Over time,the mortality rate of three storage pests tested increased rapidly, after 72h the mortality rate is stable,the mortality rate is stable, the LC50 of ethyl isothiocyanate on Tribolium castaneum Herbst,Sitophilus zeamais,Rhyzopertha dominica F. was 0.74μg/ml, 0.66μg/ml,1.6μg/ml, and EITC has equal fumigant activity as AITC; When the ratio of allyl isothiocyanate and ethyl isothiocyanates is 5:1 by weight,co-toxicity coefficient of Mixture was 307.84,163.39,174.82, show synergistic effect significantly;2, when the concentration of AITC was 2μg/ml, AITC show greater than 95% inhibition rate on Alternaria brassicae, Rhizoctonia solani, Sclerotium rolfsii, Fusarium oxysporum in the soil, and by statistical analysis of Fusarium oxysporum The EC50 was 0.17μg/ml, EC95 was 0.98μg/ml; other isothiocyanates were much lower than the activity of AITC, the overall activity show:AITC> aliphatic isothiocyanates> aromatic isothiocyanate;3, AITC has the highest fumigation activity on Meloidogyne incognita, LC50 was 0.46μg/ml only, butyl isothiocyanate and phenyl isothiocyanate followed, the other aliphatic isothiocyanate esters were lower, the activity aromatic isothiocyanate was the lowest; benzyl isothiocyanate and 2-phenyl ethyl isothiocyanate showed eual contact toxicity, LC50 were respectively 6.41μg/ml,7.32μg/ml,When the ratio of allyl isothiocyanate and ethyl isothiocyanates is 5:1 by weight,When the concentration of AITC was 50μL/kg, the disease control effect of cucumber was 94.5%, higher than the allyl isothiocyanate cyanate(67%), higher than 20% of the control (using the concentration of 40mg/kg, control efficacy was only 33.77%).This article also studied synthesis technology optimization of ethyl isothiocyanate, the reaction of sodium hydroxide, ethylamine, and carbon disulfide gain, and then decomposed dithiocarbamate salts to ethyl isothiocyanate reagents, and synthesis process optimization, the yield grow from the initial 45% to 55%.