Naeri-hiilamardika (Brassicogethes aeneus) lõhnaeelistuste käitumiskatse ja lõhnapüünise tõhusus
Laen...
Kuupäev
2018
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Naeri-hiilamardikas (Brassicogethes aeneus) on rapsi kui ühe enamkasvatatava ristõielise
õlikultuuri arvukaim kahjustaja Euroopas. Tema tõrjumiseks on kasutatud peamiselt
püretroididel põhinevaid insektitsiide, mille suhtes on mardikatel praeguseks välja
kujunenud resistentsus. Paraku on püretroidipõhised insektitsiidid ristõieliste kultuuride
kasvatamisel jätkuvalt kasutusel, mistõttu on keskkonda säästvamate ja jätkusuutlikumate
tõrjemeetodite väljatöötamine vajalik.
Käesolev magistritöö tugineb naeri-hiilamardika lõhnaeelistuste hindamisele. Töö käigus
teostati olfaktomeetria katse ja lõhnapüünise katse. Olfaktomeetria katsega testiti hiilamardikate
käitumislikke vastuseid erinevate lõhnaainete suhtes ja otsiti sobivat katsemetoodikat
olfaktomeetrilistele katsetele. Lõhnapüünise katsega sooviti kindlaks teha
püüniste atraktiivsus hiilamardikatele, et pakkuda lihtsat meetodit nende arvukuse ja
majandusliku tõrjekriteeriumi hindamiseks rapsi tootmispõllul. Sellest tulenevalt oli töö
eesmärk välja töötada usaldatav metoodika hiilamardikatega tehtavatele olfaktomeetrilistele
katsetele ning kontrollida alternatiivse tõrjevahendina väljatöötamisel oleva dsRNA
preparaadi mõju taimede poolt emiteeritavatele lõhnasignaalidele ja seega naeri-hiilamardika
peremeestaime otsingukäitumisele. Lisaks oli eesmärgiks selgitada välja lõhnapüünise
sobivus hiilamardikate arvukuse seiramiseks talirapsipõllul Eesti tingimustes.
Olfaktomeetria katsega leitud usaldusväärsete kontrollkatse variantidena võib emastele
soovitada neutraalset katset puhta õhuga ja positiivset katset (72 tunnise nälgimisajaga)
hariliku tõlkjaga. Mõlemast soost isenditele sobib negatiivseks kontrolliks lavendliõli.
Samuti selgus, et dsRNA preparaat ei mõjutanud hiilamardikate käitumist. Lõhnapüünise
katses osutus, et püünised polnud hiilamardikatele selektiivselt atraktiivsed, kuid võiksid
sobida nende arvukuse hindamiseks rapsipõllul. Hiilamardikate keskmist arvukust
mõjutas ilmastik (päevane keskmine õhutemperatuur, sademed), rapsi kasvustaadium ja
katsepõld. Keskmised arvukused olid kõrgeimad 22. mail, vahetult pärast mardikate
suuremat migratsiooni põldudele, ja 30. mail, kui rapsitaimed olid jõudnud täisõitsemise
kasvufaasi. Lisaks oli arvukus kõrgeim Kuivati rapsipõllul, seega on vajalik rõhutada, et
taimekahjurite eduka seire tagab kõigi tootmispõldude hindamine individuaalsetena.
The pollen beetle (Brassicogethes aeneus) is one of the most widely spread and destructive pests of cruciferous oilseed crops in Europe. To control this pest mainly pyrethroid-based insecticides have been used to which beetles have developed resistance. Unfortunately, pyrethroid-based insecticides are still used in cruciferous crop production, which is why the development of a more environmentally friendly and more sustainable control method is necessary. This master's thesis is based on the assessment of the odour preference of the pollen beetle. During the work, an olfactometric test and an odour-baited trap test were performed. The olfactometric test was carried out to test the effect of a dsRNA product (currently under development) on the host plant searching behaviour of the pollen beetle. The odour-baited trap test attempted to identify the attractiveness of traps for pollen beetles, in order to provide a simple method for monitoring their abundance in oilseed rape fields. Thereof, the first aim was to test the pollen beetle’s behavioural responses to various fragrances in order to find an appropriate method for olfactometric experiments to be able to test whether the dsRNA product affects beetle behaviour. Additionally the aim was to study the suitability of the odour-baited trap to monitor the abundance of pollen beetles in winter oilseed rape under Estonian climatic conditions. According to the results, the dsRNA product did not affect the searching behaviour of pollen beetles. In addition, reliable control test options were found for pollen beetles. For females neutral tests with clean air and positive tests (with 72 hours without feeding) with Bunias orientalis L. (Turkish rocket or warty cabbage) proved to be giving trustworthy results, while lavender oil was suitable as a negative control for specimens of both sexes. The odour-baited traps were found not to be selectively attractive to pollen beetles, still they could be suitable for assessing pollen beetle abundance in oilseed rape fields. The average abundance of pollen beetles was influenced by the weather (average daily air temperature, rainfall), oilseed rape growth stage and the study field. The average abundance was the highest on May 22, which was shortly after the start of the beetle migration to the fields (green bud stage), and on May 30, when the oilseed rape plants had reached the full flowering growth stage. In addition, despite the fields being close to each other, beetle abundance varied significantly among fields, which is why it is necessary to emphasize the importance of monitoring beetle abundance in every field regardless their proximity to each other, before making pest management decisions.
The pollen beetle (Brassicogethes aeneus) is one of the most widely spread and destructive pests of cruciferous oilseed crops in Europe. To control this pest mainly pyrethroid-based insecticides have been used to which beetles have developed resistance. Unfortunately, pyrethroid-based insecticides are still used in cruciferous crop production, which is why the development of a more environmentally friendly and more sustainable control method is necessary. This master's thesis is based on the assessment of the odour preference of the pollen beetle. During the work, an olfactometric test and an odour-baited trap test were performed. The olfactometric test was carried out to test the effect of a dsRNA product (currently under development) on the host plant searching behaviour of the pollen beetle. The odour-baited trap test attempted to identify the attractiveness of traps for pollen beetles, in order to provide a simple method for monitoring their abundance in oilseed rape fields. Thereof, the first aim was to test the pollen beetle’s behavioural responses to various fragrances in order to find an appropriate method for olfactometric experiments to be able to test whether the dsRNA product affects beetle behaviour. Additionally the aim was to study the suitability of the odour-baited trap to monitor the abundance of pollen beetles in winter oilseed rape under Estonian climatic conditions. According to the results, the dsRNA product did not affect the searching behaviour of pollen beetles. In addition, reliable control test options were found for pollen beetles. For females neutral tests with clean air and positive tests (with 72 hours without feeding) with Bunias orientalis L. (Turkish rocket or warty cabbage) proved to be giving trustworthy results, while lavender oil was suitable as a negative control for specimens of both sexes. The odour-baited traps were found not to be selectively attractive to pollen beetles, still they could be suitable for assessing pollen beetle abundance in oilseed rape fields. The average abundance of pollen beetles was influenced by the weather (average daily air temperature, rainfall), oilseed rape growth stage and the study field. The average abundance was the highest on May 22, which was shortly after the start of the beetle migration to the fields (green bud stage), and on May 30, when the oilseed rape plants had reached the full flowering growth stage. In addition, despite the fields being close to each other, beetle abundance varied significantly among fields, which is why it is necessary to emphasize the importance of monitoring beetle abundance in every field regardless their proximity to each other, before making pest management decisions.
Kirjeldus
Magistritöö
Maastikukaitse ja -hoolduse õppekaval
Märksõnad
magistritööd, käitumiskatsed, Naeri-hiilamardikas, lõhnapüünised