Hiilamardika erinevate põlvkondade arvukused ja toidutaimede eelistused
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Kuupäev
2018
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Naeri-hiilamardikas (Brassicogethes aeneus sün. Meligethes aeneus F.; Coleoptera:
Nitidulidae) on kõige arvukam kahjur nii Euroopa, kui ka Eesti rapsi põldudel. Euroopas
on viimasel ajal süvenenud probleem naeri-hiilamardika kahjustuste suurenemisega, sest
mardikatel on pikaaegse taimekaitsevahendite kasutamise või üle doseerimise tõttu
kujunenud välja resistentsus teatud taimekaitsevahendite (püretroidide) suhtes. Seetõttu
tuleb leida uusi lahendusi jätkusuutliku ja keskkonnasõbraliku taimekaitse väljatöötamiseks,
selleks aga tuleb tundma õppida kahjurputuka bioloogiat ja käitumist.
Käesoleva magistritöö eesmärgiks oli kevadiste ja hilissuviste välitööde käigus selgitada
välja naeri-hiilamardikate talvitunud ja talvituma suunduvate põlvkondade arvukused
erinevatel põllumajandusmaastiku elementidel. Uurimiseesmärgiks oli ka selgitada, kui
palju naeri-hiilamardika populatsioon suve jooksul suureneb. Kolmandaks uurimiseesmärgiks
oli selgitada välja toidutaimede eelistused talvituma suunduvatel ja talvitunud
mardikatel, ning selgitada välja ka toidutaimede värvuste eelistused. Viimaseks
uurimiseesmärgiks oli selgitada välja, kas 2017. aasta naeri-hiilamardikate arvukused ja
toidutaimede eelistused erinevad 2016. aastal saadud tulemustega. 2016. aasta tulemusi
võrreldi Gerda Arrase lõputööga.
Antud magistritöös selgus, et kuigi kevadel oli talvitumiskohtadest väljuv naerihiilamardikate
arvukus madal, suutsid nad oma populatsiooni suve jooksul 44 korda
suurendada. Leiti, et maastikuelement mõjutas oluliselt talvitunud ja talvituma suunduvate
naeri-hiilamardikate arvukust. Talvitunud naeri-hiilamardikaid leiti kõige rohkem
puiskoridorist ja metsaservast. Kõige rohkem suundus talvituma naeri-hiilamardikaid
rohumaalt ja rohtselt põlluservalt. Magistritööst selgus, et naeri-hiilamardikatel oli
toidutaimede värvuse suhtes eelistused. Talvitunud naeri-hiilamardikad toitusid kollast ja
valget värvi õitel, ning talvituma suunduvad naeri-hiilamardikad toitusid paljudel
erinevatel õitsevatel taimedel.
The pollen beetle (Brassicogethes aeneus syn. Meligethes aeneus F.; Coleoptera: Nitidulidae) is one of the most numerous pests in European and Estonian oilseed rape fields. In Europe, the pollen beetle problem has intensified recently, as beetles have become resistant to certain pesticides (pyrethroids) due to long-term use and overuse of plant protection products. In order to develop more sustainable methods to control pollen beetle abundance, knowledge is needed of the biology and behaviour of this pest. The first aim of this master’s thesis was to study the abundance of overwintered and new generation pollen beetles in various agricultural landscape elements in the spring and late summer. The second aim was to study how much does the population of pollen beetles increase during the summer. The third aim was to study the food plant (species and flower colour) preferences of overwintered and new generation pollen beetles. The last aim was to find out whether the abundance and food plant preference of pollen beetles in 2017 differ from the results obtained in 2016 (master’s thesis of Gerda Arras). Although, the abundance of overwintered pollen beetles was low in 2017, they were able to increase their abundance by 44 times during the summer. Landscape element influenced the abundance of overwintered and new generation pollen beetles. Overwintered beetles were mostly found next to lines of trees and in forest edges, while new generation beetles were the most abundant in grasslands and narrow crop edges. According to the results of this study pollen beetles had a preference regarding the flower colour of their food plants. The overwintered generation of pollen beetles fed on yellow and white coloured flowers and new generation pollen beetles fed on many different flowering plants.
The pollen beetle (Brassicogethes aeneus syn. Meligethes aeneus F.; Coleoptera: Nitidulidae) is one of the most numerous pests in European and Estonian oilseed rape fields. In Europe, the pollen beetle problem has intensified recently, as beetles have become resistant to certain pesticides (pyrethroids) due to long-term use and overuse of plant protection products. In order to develop more sustainable methods to control pollen beetle abundance, knowledge is needed of the biology and behaviour of this pest. The first aim of this master’s thesis was to study the abundance of overwintered and new generation pollen beetles in various agricultural landscape elements in the spring and late summer. The second aim was to study how much does the population of pollen beetles increase during the summer. The third aim was to study the food plant (species and flower colour) preferences of overwintered and new generation pollen beetles. The last aim was to find out whether the abundance and food plant preference of pollen beetles in 2017 differ from the results obtained in 2016 (master’s thesis of Gerda Arras). Although, the abundance of overwintered pollen beetles was low in 2017, they were able to increase their abundance by 44 times during the summer. Landscape element influenced the abundance of overwintered and new generation pollen beetles. Overwintered beetles were mostly found next to lines of trees and in forest edges, while new generation beetles were the most abundant in grasslands and narrow crop edges. According to the results of this study pollen beetles had a preference regarding the flower colour of their food plants. The overwintered generation of pollen beetles fed on yellow and white coloured flowers and new generation pollen beetles fed on many different flowering plants.
Kirjeldus
Magistritöö
Maastikukaitse ja -hoolduse õppekaval
Märksõnad
magistritööd, Naeri-hiilamardikas, kahjurid, raps, talvitumine, maastikuelemendid, toidutaimed