6种药剂林间注干施药防控松材线虫效果分析

Field efficacy of six trunk-injected pesticides on Bursaphelenchus xylophilus

为研究注干施药预防松材线虫Bursaphelenchus xylophilus的效果,以6种松材线虫药剂林间注干,测定了施药2 a内的防治效果。采用高效液相色谱(HPLC)测定了各药剂主要有效成分注干后3个月和1 a的在树体残留动态,并利用松材线虫恒温扩增核酸试纸条精准检测了注药后死亡松树体内松材线虫数量。结果表明:6种注干药剂林间防治后,对松材线虫防治效果存在显著差异(P<0.05),各种注干药剂在注干2 a后将马尾松Pinus massoniana的死亡率控制在0.4%~4.4%,以甲维盐、阿维菌素、啶虫脒为主要成分的药剂注干防治效果在80%以上;药后1 a高效液相色谱(HPLC)抽检测定的树体内各药剂均有残留(枯死松树中未检测到),其中甲维盐质量分数较高,平均为(0.15±0.11)mg·kg^(-1)。检测注药后死亡松树体内均有松材线虫,且平均至少为897.34条·g^(-1),说明能在树体内传导的注干药剂均有一定的防效及持效期,可在林间推广和应用。

Forest efficacy of six liquid-formulated trunk-injected pesticides(avermectin, emamectin benzoate,matrine and acetamiprid) were studied using auto flow trunk injection. After 15 months residues from liquidformulated trunk-injections in pine were recovered and detected using high-performance liquid chromatography(HPLC). Also, positive and quantitative detection of Bursaphelenchus xylophilus(BX) in dead pine trees was studied with a BX Isothermal Amplification Diagnostic Kit. Results showed that the prevention effect from the six liquid-formulated trunk injection pesticides was significant(P<0.05) with one injection controlling pine death rate between 0.4%-4.4% for two consecutive years. Avermectin, emamectin benzoate, and aloperine with trunk-injection slowed the spread of pine wilt disease with a field efficacy above 80%. All liquid-formulated residue concentrations in the trunk xylem were reached except dead pine trees one year after injection the maximum residue concentration was found with emamectin benzoate [having at least(0.15 ± 0.11) mg·kg-1].Also, after injection all pine trees died due to BX nematodes with an average BX nematode content of at least897.34 g-1in the trunk xylem. Thus, because of its favorable effect and long duration of efficacy, this liquidformulated pesticide injection could be popularized and used in practical control.