Ristõieliste nuutri (Plasmodiophora brassicae) tõrjevõimalused rapsil
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Kuupäev
2022
Kättesaadavus
27.08.2022
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Ristõieliste nuuter on raskesti tõrjutav juurehaigus, mille tõrjevõimalusi on katsetatud
labori tingimustes, kasutades erinevaid biofungitsiide ning nakkuse ennetamiseks on
kasutatud põldude lupjamist.
Käesoleva magistritöö eesmärk on hinnata granuleeritud lubiväetise prototüübi ja
bioloogilise päritoluga fungitsiidi Prestop mõju ristõieliste nuutri tõrjes ning hinnata P.
brassicae hulka Eesti rapsipõldudel.
Katsed viidi läbi 2021. aasta taimekasvatusperioodil Eerika katsepõllul, kus on varasemalt
täheldatud nuutriga nakatunud taimi. Katsepõllule rajati neli erinevat katsevarianti kolmes
korduses: granuleeritud lubiväetis; Prestop; granuleeritud lubiväetis ja Prestop ning kontroll
(töötlemata). Mullaproovidest eraldati DNA, millest määrati qPCR metoodikaga patogeeni
kontsentratsioon. Tulemuste analüüsil ilmnes, et põllumullas ei olnud ühelgi töötlusel
statistiliselt olulist mõju. Nii Prestopi kui ka granuleeritud lubiväetise efektiivsust võis
mõjutada erakordselt kuiv kasvuperiood, biofungitsiidis sisalduv antagonistliku organismi
toimemehhanism kui ka katsealalt võetavate mullaproovide metoodika.
Suuremahulise monitooringu tulemuste analüüsil leiti, et mullast P. brassicae
kontsentratsiooni määramine on abiks külvikorra planeerimisel. Mulla pH ning patogeeni
kontsentratsiooni vahel esineb nõrk negatiivne korrelatsioon. Antud uurimistöö tulemuste
põhjal võib järeldada, et happeliste muldade lupjamisega saab vähendada ristõieliste
nuutrisse nakatumist. Taluniku jaoks on olulised indikaatoriks millisesse P.brassicae
nakkuse riskigruppi põld kuulub ning milline on antud põllu pH, et leida endale sobilik moodus põllul edasiste tööde planeerimiseks. Lisaks võib antud uurimistöö tulemuste põhjal
järeldada, et biofungitsiidide mõju ristõieliste nuutri tekitaja P. brassicae kontsentratsiooni
vähendamiseks tuleks rohkem uurida tugevalt nuutri tekitajaga saastunud põldudel.
Clubroot of crucifers is a hard-to-repel fungal disease, the control possibilities which have been tested in laboratory conditions with various biofungicides. However, to prevent infection, liming is used on the fields. The aim of this master's thesis is to assess the impact of a lime fertilizer prototype and biofungicide Prestop on supressing the clubroot pathogen and to assess the concentration of P. brassicae in Estonian agricultural soils. In this study, the field trial was carried out during the 2021 cropping season in the Eerika research centre, where plants infected with clubroot have previously been observed. Different experimental variants included Prestop, lime fertilizer, both of the above and control in three replications. From the soil samples, the DNA was extracted, from which the concentration of the pathogen was determined by qPCR method. The analysis of the results showed that none of the tested products had a statistically significant effect. The efficacy of both Prestop and granular lime fertilizer may have been influenced by an exceptionally dry growing season, different mechanisms of action of antagonistic organisms contained in the biofungicide, as well as the methodology of soil sampling. Analysis of the results of large-scale monitoring found that determining the results of P. brassicae from the soil can help farmers in crop rotation planning. Soil pH and the concentration of the pathogen had weak negative correlation. Based on the results of this research, it can be concluded that liming of acidic soils can prevent infection with clubroot disease and the effect of biofungicide Prestop to reduce the concentration of P. brassicae should be studied more in field experiments.
Clubroot of crucifers is a hard-to-repel fungal disease, the control possibilities which have been tested in laboratory conditions with various biofungicides. However, to prevent infection, liming is used on the fields. The aim of this master's thesis is to assess the impact of a lime fertilizer prototype and biofungicide Prestop on supressing the clubroot pathogen and to assess the concentration of P. brassicae in Estonian agricultural soils. In this study, the field trial was carried out during the 2021 cropping season in the Eerika research centre, where plants infected with clubroot have previously been observed. Different experimental variants included Prestop, lime fertilizer, both of the above and control in three replications. From the soil samples, the DNA was extracted, from which the concentration of the pathogen was determined by qPCR method. The analysis of the results showed that none of the tested products had a statistically significant effect. The efficacy of both Prestop and granular lime fertilizer may have been influenced by an exceptionally dry growing season, different mechanisms of action of antagonistic organisms contained in the biofungicide, as well as the methodology of soil sampling. Analysis of the results of large-scale monitoring found that determining the results of P. brassicae from the soil can help farmers in crop rotation planning. Soil pH and the concentration of the pathogen had weak negative correlation. Based on the results of this research, it can be concluded that liming of acidic soils can prevent infection with clubroot disease and the effect of biofungicide Prestop to reduce the concentration of P. brassicae should be studied more in field experiments.
Kirjeldus
Magistritöö
Põllumajanduse õppekaval
Märksõnad
magistritööd, qPCR, mullapatogeen, ristõielistenuuter, biotõrje, P. brassicae, Roheline Ülikool (töö toetab EMÜ Rohelise Ülikooli põhimõtteid), keskkonnatehnika, keskkonnasõbralikud tooted