摘要
田间试验结果，除草剂氟乐灵４８％乳油以０．８６４ｋｇ／ｈｍ２作棉苗播前土壤处理，可明显减轻棉花枯萎病的发生，在现蕾期，施用氟乐灵后对感病品种沪棉２０１１和抗病品种中棉１２枯萎病株发病率的防治效果分别为４８．２５％～６９．４２％和４９．４１％～７０．５９％；病害严重度也明显下降，对沪棉２０１１和中棉１２的抑制作用分别为５５．９８％～６４．７８％和４６．３６％～７０．４５％。从棉花收获后进行的剖秆检查看，氟乐灵施用后不仅降低了枯萎病菌对棉花的侵染率，对沪棉２０１１和中棉１２的防治作用分别为１６．０２％和２６．８２％；而且也减轻了受侵棉花植株木质部的病变程度，对沪棉２０１１和中棉１２植株木质部病变的抑制作用分别为２２．０２％和３６．３３％，对施药２个月后土壤中枯萎病菌接种体密度的测定结果表明，氟乐灵并不影响土壤中枯萎病菌的接种体密度。综上所述结果，氟乐灵播前土壤处理可以减轻田间棉花枯萎病的发生，其原因是氟乐灵处理诱发了棉株对枯萎病的抗侵入和抗扩展能力。
Field trials in Cixi cotton belt,Zhejiang Province, China revealed that presowingsoil treatment with trifluralin at 0.864kg a. i./hm2 significantly suppressed cotton Fusariumwilt caused by Fusarium oxysporum f.sp vasinfectum.At squaring stage,trifluralin treatmentreduced the wilt incidence by 69.44%and 49.4%for susceptible and resistant cultivar,re-spectively;The treatment also expressed marked suppression of the severity of both cultivars(64.8%and 46.4%,respectively)at squaring,Xylem discoloration rating of cross sectionfrom all the tested plants after harvesting showed that trifluralin treatment reduced thepathogen infections and suppressed the disease damage in the xylem of infected plants.Thequantitative assays after the herbicide treating showed no significant difference in inoculumdensity of the pathogen between the treated and untreated soil.The results suggest that soilincorporated trifluralin reduces incidence and severity of cotton Fusarium wilt through the in-duced resistance of cotton seedlings。
出处
《棉花学报》
CSCD
北大核心
1994年第2期122-125,共4页
Cotton Science
基金
浙江省自然科学基金
关键词
氟乐灵
棉花
枯萎病
抗病性
induced resistance,cotton,Fusarium wilt,trifluralin
