Study On The Trapping Effect Of Solar Light Traps Against Peanut Insect Pests

Insect light traps powered by electricity lines do not work properly in some areas where power grids are imperfect.Therefore,the development of environment-friendly and highly effective solar light traps can expand the application areas of ligh trap technology against insect pests.Thus,this study explored the influence of different solar panels,storage batteries,orientations and proportions of shadow on the power storage capacity of solar light traps and selected the optimal combination for energy supply.Combining the optimal energy-providing combination with potential special light sources for insect pests in peanut fields to make and produce solar light traps,which were applyed in controlling insect pests in peanut fields.Moreover,we ananlyzed the species and numbers,occurrence period,peak period of light trap and light rhythm of main insect pests,neutral insects and natural enemy insects trapped by solar light traps.The main results in this study are as follows:1.Optimized combination of energy-providing units in solar light trapsThe automatic testing equipment for battery comprehensive parameters was used to estimate the photoelectric conversion efficiency of different orthogonal designs L₉（3⁴）.When the ampere hour was as the indicator,the shading area（R=38.92,p<0.01）had the greatest and significant influence on the photoelectric conversion efficiency,and then battery type（R=6.43,p<0.05）.However,the orientations（R=4.59）and types of solar panels（R=3.23）had the weak and no significant effect on the photoelectric conversion efficiency.When the watt hour was as the indicator,the shading area（R=445.06,p<0.01）had the greatest and significant impact on the photoelectric conversion efficiency.However,the battery types（R=51.92）,solar panel orientations（R=42.11）and solar panel types（R=23.17）had no significant effect on the photoelectric conversion efficiency.Combining the results of ampere hour and watt hour together,the optimal combination of energy-providing units was monocrystalline silicon,lithium battery,180°towards south and no shadow.Solar light traps were made by the optimal combination of energy supply components combining with potential special light sources against insect pests in the peanut field.Structural characteristics of the solar light traps were to use plastic baffles replacing power grids and have the escapping device for natural enemies,which was benefit for protecting natural enemies.2.Species and proportion of insects trapped by solar light traps in peanut fieldOur results showed that the total number of insects trapped by the six solar light traps of two light sources were 105,579.Scarabaeoidae were 80,500,which were more than76%of the total trapped insects.The number of Anomala corpulenta was up to 52,603,which was the biggest in Scarabaeoidae and were about 50%of the total trapped insects.In addition,the number of Geotrupidae,Dytiscidae and Hydrophilidae trapped by solar light traps were 2,244,1701 and 4866 respectively,which were about 8%of the total trapped insects.Besides,the number of Carabidae,Cicindelidae and Reduviidae trapped by solar light traps were 1,495,760 and 211 respectively,which was about 2%of the total trapped insects and lower than the trapped insect pests and neutral insects.3.The trapping effect of solar light traps on insects in peanut fieldThe peak period of the insect pests,neutral insects and natural enemies in the peanut field trapped by solar light traps was mainly from late May to early July.For the insect pests,the number of Scarabaeoidae and Elateridae trapped by light source A was not significantly different from that trapped by light source B.However,the number of Gryllotalpidae（p=0.04）trapped by light source A was significantly higher than that trapped by light source B.For the neutral insects,the number of Dytiscidae,Hydrophilidae and Geotrupidae trapped by two light sources showed no significant differences.For the natural enemies,the number of Cicindelidae,Carabidae and Geotrupidae trapped by two light sources showed no significant differences too.In addition,the number of Gryllotalpidae trapped by the six solar light traps in sunny days was significantly higher than those on cloudy days（p<0.001）,but there was no significant difference in the trapping amount of Scarabaeoidae and Elateridae between sunny and cloudy days.Also,there was no significant difference in the trapping amounts of neutral insects（Dytiscidae,Hydrophilidae and Geotrupidae）and natural enemies（Cicindelidae,Carabidae and Reduviidae）between sunny and cloudy days.4.Light rhythm of different insects trapped by solar light traps in peanut fields The peak periods of the three cockchafers Anomala corpulenta,Holotrichia parallela and Maladera verticalis were from 20:00-21:00 trapped by solar light traps in peanut fields.At the peak period,the amount of H.parallela（p<0.001）and M.verticalis（p<0.01）trapped by light source B were significantly higher than that trapped by light source A.There were no significant differences in the trapping number of Gryllotalpidae and Elateridae between the two light sources.The peak period of neutral insects（Dytiscidae and Hydrophilidae）was from 20:00-21:00.At the peak period,the amount of Dytiscidae（p<0.05）and Hydrophilidae（p<0.05）trapped by light source B were significantly higher than that trapped by light source A.However,there was no obvious peak period of natural enemies（Cicindelidae,Carabidae and Reduviidae）,and there was no significant difference in the amount of them trapped by two light sources.