Effects Of Three Seed-coating Agents On Arthropod Communities In The Corn Fields

During the whole corn growth period,a total of 34 species of arthropod communities which composed of 10 orders,28 families were identified in the maize field investigation.Thereinto,23 species from 8 orders and 18 families were pest,and the other 11 species which belonged to 5 orders and 10 families were predatory enemies.Anaphothrips sp.,Rhopalosiphum maidis Fitch,Laodelphax striatellus Fallen,Helicoverpa armigera Hübner,Ostrinia furnacalis Guenee,Proxenus lepigone Moschler,Agromyzidae,Lathridiidae,Chrysomelidae,Alticinae,Trigonotylus ruficornis Geoffroy,Orius minulus Linnaeus,Propylaea japonica Thunberg,Harmonia axyridis Pallas,Chrysopidae,Erigonidium graminicola Sundevall,Theridion octomaculatum Boes.et Str.,Misumenops tricuspidata Fahricius,Trichogrammatidae and Formicidae were found at corn small trumpet and grouting period.Dichocrocis punctiferalis Guenee,Mythimna separata Walker,Parnara guttata Bremer et Grey,Agromyzidae were mainly found during the grain filling stage.And the other species were only found at corn small trumpet period.Three kinds of seed-coating agents,Fortenza Duo,carbofuran and imidacloprid were selected to dress the seeds,and the effect of these three seed-coating agents on the species of arthropods in maize field was studied by field experiment.During the corn growth period,28 species of arthropods,including 18 species of pest and 10 species of predatory enemies,had been found after treating seed with Fortenza Duo;25 species of arthropods,including 16 species of pest and 9 species of predatory enemies,had been found after treating seed with carbofuran;and 29 species of arthropods,including 19 species of pest and 10 species of predatory enemies,had been found after treating seed with imidacloprid.There were no significant differences between the control experiments and the treatments of various concentrations,and no effects on the diversity and quantity of arthropods when the seeds were treated with Fortenza Duo,carbofuran or imidacloprid seed-coating agents..During the grain filling period,the number of aphis was increased to a certain extent by treating with Fortenza Duo or imidacloprid seed-coating agents,while decreased by treating with carbofuran seed-coating agent.Meanwhile,the number of Of.urnacalis was increased under the three treatments;the number of D.Rpunctiferalis was increased by carbofuran seed-coating agent,but decreased by imidacloprid seed-coating agent,and there was no obviously influence treated with Fortenza Duo seed-coating agent;the number of H.armigera had no significant effect under the three treatments.On the whole,the treatment effect of seed dressing with Fortenza Duo was significant for the control of D.punctiferalis in female spike and spikelet at the harvest stage,but no control effect of Lepidoptera in other parts of the corn.The treatment effects of seed dressing with imidacloprid or carbofuran agents were not obvious for the control of Lepidoptera at the maize harvest time.Fortenza Duo was selected to control the pest in the corn field.