Study On The Chemical Control Technology Of Fusarium Crown Rot Of Wheat

Fusarium crown rot of wheat is a kind of soil-borne disease thatinfected by a variety of pathogenic fungi, it occur in most of the world’s wheatproduction areas. In recent years, it has a growing trend in Henan and other provincesin China, and brings serious losses on the production of wheat.The control ofFusarium crown rot of wheat is very difficult, because of lacking of resistant varietiesand efficient chemical fungicides at present. In this study, in order to screening theeffective fungicides that can control the Fusarium crown rot of wheat, the activity of aseries of single and compound fungicides to Fusarium pseudograminearum, which isthe dominant pathogen of Fusarium crown rot of wheat, were determined in vitro, potexperiment in greenhouse and plot experiment in the field.The main results are followas:1. The results indicated that Tebuconazole has the best inhibiting effect on thehypha growth of pathogen in vitro, EC50is0.871mg/kg. Fludioxonil, Carbendazimand Azoxystrobin also have good inhibiting effect on the hypha growth of pathogen,EC50are1.180mg/kg,1.556mg/kg and1.603mg/kg respectively. In the test ofco-toxicity, Carbendazim and Difenoconazole mixtures have an obvious synergisticactivity, therein the EC50of Carbendazim plus Difenoconazole (3:1) is0.140mg/kg,the co-toxicity coefficient (CTC) is2173.947, with an obvious synergistic activity inboth parties. The EC50of three compound preparations, Carbendazim plusDifenoconazole (1:1), Carbendazim plus Triticonazole (1:1) and Carbendazim plusDifenoconazole (1:3) are0.152mg/kg,0.422mg/kg and1.427mg/kg, CTC are1518.445,804.039and213.281respectively, also have obvious synergistic activity.The EC50of other three compound preparations, Carbendazim plus Azoxystrobin (1:1),Difenoconazole plus Fludioxonil (1:1) and Carbendazim: Triticonazole (1:1)are1.119mg/kg,1.837mg/kg and2.649mg/kg, the CTC are141.122,114.343and101.625respectively, show an additive activity. The CTC of other compoundpreparations are smaller than70, with an antagonism activity in both parties. 2、The results in pot experiments indicated that the effect of seed treated withFludioxonil is the best, with64.91%control effect in average. The followed areDingmiaoxin, Azoxystrobin, Carbendazim, and Triticonazole， with the averagecontrol effectiveness over than40%respectively. In fungicide mixtures, Carbendazimplus Azoxystrobin(1:1) has the best control effect, with48.07%control effectivenessin average, The followed are Difenoconazole plus Fludioxonil (1:1), Carbendazimplus Tebuconazole (1:1), and Carbendazim plus Triticonazole(1:1) with the averagecontrol effectiveness of43.51%,39.75%and35.97%respectively.3、The results in field experiments indicated that the effect of treated seed withCarbendazim plus Difenoconazole(1:1) is the best, with65.64%control effectivenessin average in the seedling stage. The followed are Azoxystrobin, Carbendazim plusAzoxystrobin(1:1), Difenoconazole and Fludioxonil, with the average controleffectiveness over than50%respectively in this stage. In returning green jointingstage, the effect of treated seed with Difenoconazole is the best, with42.40%controleffect in average; The followed are Carbendazim plus Difenoconazole (1:1),Carbendazim plus Azoxystrobin (1:1), Arbendazim and Shimaidan with the averagecontrol effect over than30%respectively. In grain filling stage, the effect of treatedseed with Shimaidan is the best, with51.97%control effect in average; The followedare Carbendazim plus Difenoconazole (1:1) and Tebuconazole with the averagecontrol effect of49.98%and48.76%. Generally spray Carbendazim or Diniconazolein returning green jointing stage have better control effect than single seeding treed.The results of yield increasing showed that spray Carbendazim after treated seed withCarbendazim have the best yield increasing, with the average yield of572.29kg, withgrowth rate of30.05%, The followed are spray Carbendazim after treated seed withAzoxystrobin and spray Carbendazim in returning green jointing stage, with thegrowth rate over than20%.4、The results showed that some new fungicides and their mixtures have goodcontrol effect in seedling stage.In Qinyang county, the effect of treated seed withBAS700050FS+BAS941091FS+BAS500012FS mixtures is the best one, with86.04%control effectiveness in average. The followed are BAS700050FS+Triticonazole+Fludioxonil，Tebuconazole and Triticonazole, with the average controleffect over than50%respectively. In Fengqiu county, the effect of treated seed withBAS700050FS+BAS941091FS+BAS500012FS is the best one, with67.62%control effectiveness in average. The followed are BAS700050FS+Triticonazole+ Fludioxonil and BAS700050FS+Triticonazole+BAS500012FS with the average controleffectiveness over than50%respectively. In returning green jointing stage, the effectof treated seed with BAS700050FS+Triticonazole+BAS500012FS mixtures is thebest in Qinyang county, with43.90%control effectiveness in average. The followedare BAS700050FS+Triticonazole and BAS700050FS+BAS941091FS+BAS500012FS mixtures, with the average control effectiveness of31.79%and30.75%. InFengqiu county, the effect of treated seed with BAS700050FS+BAS941091FS+BAS500012FS mixtures were the best, with62.23%control effectiveness inaverage. The followed are Triticonazole, BAS672020FS, with the average controleffectiveness over than40%respectively. In grain filling stage the effect of treatedseed with BAS700050FS+BAS941091FS+BAS500012FS mixtures is the best in Qinyangcounty, with30.32%control effectiveness in average. In Fengqiu county, the effect oftreated seed with BAS700050FS+Triticonazole+Fludioxonil mixtures were the best,with55.24%control effectiveness in average. In Qinyang county KINTO DUO080FSand BAS700050FS+BAS941091FS+BAS500012FS have a better yield increasing, withthe average yield of505.03kg and503.20kg; In Fengqiu county BAS700050FS+Triticonazole+Fludioxonil mixtures BAS672020FS and BAS700050FS+BAS941091FS+BAS500012FS mixtures have a better yield increasing, with the average yield of608.82kg,585.27kg and576.47kg. BAS700050FS+BAS941091FS+BAS500012FS mixtureshave a better yield increasing in two county.5、The results in demonstration field in2013-2014indicated that treated seed withShimaidan have good control effect In Qinyang and Fengqiu county, with60.06%and50.57%control effectiveness in average respectively, and Shimaidan can increaseproduction also, with the average yield of589.00kg and639.79kg,with18.88%and25.69yield increasing in average respectively.