Nove tehnologije spremljanja pojavnosti pokalic in strun (Coleoptera: Elateridae) v kmetijskih posevkih

  Stanislav GOMBOC, Lea MILEVOJ

Biotehniška fakulteta, Oddelek za agronomijo, Inštitut za fitomedicino, SI-1000 Ljubljana, Slovenija

 

Doslej smo v Sloveniji evidentirali 10 vrst iz rodu Agriotes: A. atterimus L., A. acuminatus Steph., A. ustulatus Schall., A. litigiosus Rossi, A. pilosellus Schönh., A. lineatus L., A. obscurus L., A. sputator L., A. medvedevi Dolin, A. brevis Cand. Večina teh se pojavlja v kmetijskih posevkih, kjer so predvsem strune pomembni talni škodljivci, še posebno na okopavinah. Zaradi skritega življenja ličink v tleh in nočne aktivnosti hroščev tega rodu, so bile dosedanje metode spremljanja bionomije in prognostike, časovno in delovno, zelo zahtevne in pogosto niso dale zanesljivih rezultatov. Z odkritjem feromonov pri pomembnejših evropskih vrstah rodu Agriotes in z razvojem novih talnih vab za ličinke, smo dobili nove možnosti za natančnejše spremljanje bionomije in gostote izbranih vrst. Ta metodika omogoča natančno spremljanje pojavljanja hroščev v sezoni in oceno kritičnih števil ličink na večjem zemljišču, ob relativno majhni porabi časa. Za spremljanje hroščev uporabljamo feromonske vabe različnih izvedb. Za vrste, ki plezajo, uporabljamo vabe, ki so položene na tla, tipa Soil-level, za vrste, ki letajo, pa vabe tipa VARb, na višini 40-60 cm nad tlemi. Vrste spremljamo v času od marca (maja pri vrstah A. ustulatus in A. litigiosus) do konca avgusta. Za spremljanje ličink uporabljamo posebno izvedbo talnih vab, kjer za privabljanje služi kaleča koruza in pšenica, za ohranjanje vlažnosti pa vermikulit. Tovrstni monitoring smo v letu 2000 prvič uvedli tudi v Sloveniji, na laboratorijskem polju Biotehniške fakultete v Ljubljani in na njivah Kmetijskega gospodarstva Lendava, v okolici Petišovcev. Rezultati so bili zelo dobri. V Ljubljani je bila dominantna vrsta A. lineatus, v Petišovcih pa vrsti A. ustulatus in A. sputator.

 

 

ABSTRACT

  New Monitoring Methods of Click Beatles and Wireworms (Coleoptera: Elateridae) in Field Crops

 

Until now 10 species of genus Agriotes were registered in Slovenia: A. atterimus L., A. acuminatus Steph., A. ustulatus Schall., A. litigiosus Rossi, A. pilosellus Schönh., A. lineatus L., A. obscurus L., A. sputator L., A. medvedevi Dolin, A. brevis Cand. Most of them are important pests of field crops, particularly wireworms. Due to the hidden live of larvae in the soil and night activity of adults of this genus, previous methods for estimating of bionomy and prognosis were very labour and time consuming, without realiable results. With discovering of female sex pheromones of more important Agriotes species, and with new design of soil bait traps for larvae, we got new methods for more accurate monitoring and risk assesment by this genus. This methods enable exact tracking of adults activity during the season and more exact evaluation of larval population in larger area and are less time consuming. For the capture of beatles different design of sex pheromone traps were used. For crawling species Soil-level traps were used wheares for flying species VARb type traps, placed 40-60 cm above the ground, are more suitable. The period of monitoring for adults is from March (from May by A. ustulatus in A. litigiosus) to the end of August. For trapping of larvae special design of soil bait traps is used, where germinating maize and wheat seeds are used as the bait, with vermiculit for moisture maintainance in the trap. We used this type of monitoring for the first time in the year 2000 in Slovenia on the laboratory field of Biotechnical Faculty in Ljubljana and on the fields of Agricultural Estate Lendava in vicinity of Petišovci, near the Hungarian border. The results were very promissing. The dominant species were A. lineatus in Ljubljana,  A. ustulatus and A. sputator in Petišovci.