Mary Hausbeck, Department of Plant and Av thiab Microbial Sciences, Michigan State University-Lub Xya hli ntuj 23, 2014
Lub xeev Michigan tau lees paub tias muaj kab mob me me ntawm cov dos.Hauv Michigan, tus kab mob no tshwm sim txhua peb mus rau plaub xyoos.Qhov no yog ib qho kab mob loj heev vim tias yog tias tsis kho, nws tuaj yeem sib kis tau sai thiab kis mus thoob qhov chaw loj hlob.
Downy mildew yog tshwm sim los ntawm kev puas tsuaj ntawm cov kab mob Peronospora, uas tuaj yeem defoliate cov qoob loo ntxov ntxov.Nws thawj zaug kis cov nplooj ua ntej thiab tshwm nyob rau thaum sawv ntxov ntawm lub caij off-season.Nws tuaj yeem loj hlob li greyish-ntsuab fuzzy kev loj hlob nrog faint slender me ntsis.Cov nplooj uas muaj kab mob hloov lub teeb ntsuab thiab tom qab ntawd daj, thiab tuaj yeem folded thiab folded.Cov kab mob tuaj yeem yog ntshav-ntsuab.Cov nplooj cuam tshuam tig lub teeb ntsuab ua ntej, tom qab ntawd daj, thiab tuaj yeem quav thiab tawg.Cov tsos mob ntawm tus kab mob yog qhov zoo tshaj plaws lees paub thaum lub lwg tshwm thaum sawv ntxov.
Kev tuag ntxov ntxov ntawm dos nplooj yuav txo qhov loj me.Kev kis kab mob tuaj yeem tshwm sim, thiab cov qij khaws cia ua mos, wrinkled, dej thiab amber.Asymptomatic qhov muag teev yuav germinate ntxov ntxov thiab tsim lub teeb ntsuab nplooj.Lub teeb tuaj yeem kis tau los ntawm cov kab mob thib ob, ua rau lwj.
Downy mildew pathogens pib kis nyob rau hauv qhov txias txias, qis dua 72 degrees Fahrenheit, thiab nyob rau hauv ib puag ncig ntub.Tej zaum yuav muaj ntau yam kab mob sib kis hauv ib lub caij.Spores yog tsim thaum hmo ntuj thiab tuaj yeem yooj yim tshuab tau ntev hauv huab cua ntub.Thaum qhov kub ntawm 50 txog 54 F, lawv tuaj yeem tawg ntawm cov dos cov ntaub so ntswg hauv ib thiab ib nrab mus rau xya teev.Qhov kub thiab txias thaum nruab hnub thiab luv luv lossis tsis sib haum xeeb thaum hmo ntuj yuav tiv thaiv kev tsim cov kab mob.
Overwintering spores, hu ua oospores, tuaj yeem tsim hauv cov ntaub so ntswg tuag thiab tuaj yeem pom hauv cov dos tuaj yeem pab dawb, dos culling pawg, thiab khaws cov noob muaj kab mob.Cov spores muaj cov phab ntsa tuab thiab cov khoom noj uas tsim los, yog li lawv tuaj yeem tiv taus qhov kub tsis zoo rau lub caij ntuj no thiab muaj sia nyob hauv av mus txog tsib xyoos.
Purpura yog tshwm sim los ntawm fungus Alternaria alternata, ib hom dos nplooj kab mob hauv Michigan.Nws thawj zaug manifests raws li ib tug me me dej-soaked lesion thiab sai loj hlob mus rau hauv ib tug dawb chaw.Thaum peb muaj hnub nyoog, qhov txhab yuav tig xim av mus rau ntshav, ncig los ntawm qhov chaw daj.Cov kab mob yuav coalesce, nruj cov nplooj, thiab ua rau lub taub hau rov qab.Qee lub sij hawm lub teeb ntawm lub teeb kis tau los ntawm lub caj dab lossis qhov txhab.
Nyob rau hauv lub voj voog ntawm cov av qis thiab siab txheeb ze, spores hauv qhov txhab tuaj yeem tsim dua.Yog tias muaj dej dawb, cov spores tuaj yeem loj hlob tsis pub dhau 45-60 feeb ntawm 82-97 F. Spores tuaj yeem tsim tom qab 15 teev thaum qhov txheeb ze av noo ntau dua lossis sib npaug li 90%, thiab tuaj yeem kis tau los ntawm cua, nag, thiab kev ywg dej.Qhov ntsuas kub yog 43-93 F, thiab qhov kub zoo tshaj plaws yog 77 F, uas yog qhov tsim nyog rau kev loj hlob ntawm fungi.Cov nplooj laus thiab cov tub ntxhais hluas puas los ntawm dos thrips yog cov kab mob ntau dua.
Cov tsos mob yuav tshwm sim ib mus rau plaub hnub tom qab kis kab mob, thiab cov kab mob tshiab yuav tshwm sim rau hnub thib tsib.Cov pob liab liab tuaj yeem defoliate dos cov qoob loo ntxov ntxov, ua rau lub teeb tsis zoo, thiab tuaj yeem ua rau rot los ntawm cov kab mob thib ob.Cov kab mob ntshav liab tuaj yeem muaj sia nyob lub caij ntuj no dhau ntawm cov kab mob fungal (mycelium) hauv cov dos tawg.
Thaum xaiv ib qho biocide, thov hloov ntawm cov khoom nrog ntau hom kev ua haujlwm (FRAC code).Cov lus hauv qab no teev cov khoom sau npe rau cov kab mob me me thiab ntshav me me ntawm cov dos hauv Michigan.Michigan State University txuas ntxiv hais kom nco ntsoov tias cov ntawv sau tshuaj tua kab yog cov ntaub ntawv raug cai hais txog kev siv tshuaj tua kab.Nyeem cov ntawv, raws li lawv hloov ntau zaus, thiab ua raws txhua cov lus qhia raws nraim.
* Copper: paib SC, cov khoom sib tw, N tooj liab suav, Kocide khoom, Nu-Cop 3L, Cuprofix hyperdispersant
* Tsis yog tag nrho cov khoom no yog cim nrog cov kab mob me me thiab ntshav me me;DM tau pom zoo tshwj xeeb rau kev tswj cov kab mob mildew, PB tshwj xeeb tshaj yog pom zoo rau kev tswj cov pob liab doog