In 2009, three Slovenian strains of entomopathogenic nematodes) and commercial product Entonem (active ingredient S. feltiae), were tested under laboratory conditions for their activity against adult ...cereal leaf beetles (Oulema melanopus). The nematode strains were tested at four different doses (250, 500, 1000, and 2000 infective juveniles/adult) and at three temperatures (15, 20, and 25 °C). Steinernema carpocapsae strain C101 was the most effective and showed itself to be a good alternative to chemical insecticides, and appears to have the highest potential for controlling overwintered cereal leaf beetles under field conditions. In our bioassay the temperature had the greatest influence on the efficacy of the entomopathogenic nematode strains; both S. feltiae treatments (strain B30 and Entonem) proved to work better at the lowest temperature, however the strain H. bacteriophora D54 had its best efficacy at the highest temperature in the experiment. Several species (S. feltiae and S. carpocapsae) have been efficient at lower suspension concentrations, which enables their economical usage against the cereal leaf beetle in integrated cereal production in the future.
V letu 2009 smo v laboratorijskem poskusu preizkušali učinkovitost treh domačih ras entomopatogenih ogorčic in komercialnega pripravka Entonem (aktivna snov S. feltiae) zoper odrasle osebke rdečega žitnega strgača (Oulema melanopus). Delovanje entomopatogenih ogorčic smo preizkušali pri štirih različnih koncentracijah (250, 500, 1000 in 2000 infektivnih ličink/osebek) in treh različnih temperaturah (15, 20 in 25 °C). Rasa C101 vrste Steinernema carpocapsae je bila najbolj učinkovita in bi lahko predstavljala dobro alternativo kemičnim insekticidom pri zatiranju prezimljenih odraslih osebkov rdečega žitnega strgača na prostem. V našem poskusu je imela največji vpliv na delovanje entomopatogenih ogorčic temperatura; obe obravnavanji z vrsto S. feltiae (rasa B30 in Entonem) sta bili učinkoviti tudi pri nižjih temperaturah, rasa D54 vrste H. bacteriophora pa je najbolje delovala pri najvišji temperaturi v poskusu. Ogorčici S. feltiae in S. carpocapsae sta zadovoljivo učinkovali tudi pri nižji koncentraciji suspenzije ogorčic, kar omogoča večjo gospodarnost rabo njihove uporabe pri zatiranju odraslih osebkov rdečega žitnega strgača v integrirani pridelavi žit v prihodnje.
Paper presents a larval cannibalism of green lacewings (Chrysoperla carnea), which was observed during the laboratory bioassay on non-target effect of entomopathogenic nematodes against green ...lacewings larvae. The most probable reason for larval cannibalism were undersized Petri dishes in which the bioassay was performed. Due to large number of larvae per surface unit, frequent crossing of green lacewings larvae appeared and this consequently lead to cannibalism. In most cases larger, elder larvae consumed smaller, younger larvae. Cannibalism increased with temperature rise and was the most intensive at 25 °C. At this temperature the larval mortality was 22.0 % after two days, while after four days the larval mortality reached 31.0 %.
V prispevku je predstavljen kanibalizem med ličinkami navadne tenčičarice (Chrysoperla carnea), ki se je pojavil pri laboratorijskem preučevanju neciljnega delovanja entomopatogenih ogorčic na ličinke omenjenega naravnega sovražnika. Najverjetnejši vzrok za pojav kanibalizma so bile premajhne petrijevke, v katerih je potekal poskus. Zaradi velikega števila ličink navadne tenčičarice na enoto površine, je prišlo do pogostega srečevanja ličink in posledično do kanibalizma. V večini primerov so ličinke višjega larvalnega stadija pojedle manjše ličinke. Kanibalizem se je povečeval z višanjem temperature in je bil najbolj intenziven pri 25 °C, kjer je bila smrtnost ličink dva dni po začetku poskusa 22,0 %, po štirih dneh pa 31,0 %.
In 2008 and 2009 we studied molluscicidal activity of 26 substances in 89 different treatments under laboratory conditions. The experiments in which slugs (Arion spp.) were a part took place in two ...series: 1) with the injection of active substances in slug intestines; and 2) with the application of pellets. After giving the injection we observed 100% mortality of slugs in treatments with Bacillus thuringiensis var. kurstaki (0.25 ml in 10% concentration/individual), caffeine (0.25 ml in 10% concentration/individual), sodium dodecyl sulphate (0.25 ml in 10% concentration/individual, 0.125 ml in 10% concentration/individual, 0.125 ml in 5% concentration/individual, 0.0625 ml in 10% concentration/individual), and pirimicarb (0.25 ml in 10% concentration/individual, 0.125 ml in 10% concentration/individual, 0.125 ml in 5% concentration/individual, 0.0625 ml in 10% concentration/individual). Meanwhile, the application of pellets resulted in the highest (100%) slug mortality when sodium dodecyl sulphate in 0.5% concentration with caraway as a supplement was used.
Z V letih 2008 in 2009 smo v laboratorijskih razmerah preizkušali limacidno delovanje 26 snovi v 89 različnih obravnavanjih. Poskusi, v katere smo vključili polže lazarje (Arion spp.), so potekali v dveh serijah, in sicer z injiciranjem aktivne snovi v prebavilo polžev in z uporabo pelet. Pri injiciranju smo 100 % smrtnost polžev ugotovili v obravnavanju z bakterijo Bacillus thuringiensis var. kurstaki (0,25 ml v 10 % koncentraciji/osebek), kofeinom (0,25 ml v 10 % koncentraciji/osebek), natrijevim dodecil sulfatom (0,25 ml v 10 % koncentraciji/osebek; 0,125 ml v 10 % koncentraciji/osebek; 0,125 ml v 5 % koncentraciji/osebek; 0,0625 ml v 10 % koncentraciji/osebek), in pirimikarbom (0,25 ml v 10 % koncentraciji/osebek; 0,125 ml v 10 % koncentraciji/osebek; 0,125 ml v 5 % koncentraciji/osebek; 0,0625 ml v 10 % koncentraciji/osebek), medtem ko smo največjo (100 %) smrtnost polžev pri uporabi pelet dosegli z natrijevim dodecil sulfatom v 0,5 % koncentraciji z dodatkom kumine.