Toxicological and ultrastructural analysis of the impact of pesticides used in temperate fruit crops on two populations of Chrysoperla externa (Neuroptera, Chrysopidae) (original) (raw)
Related papers
Chilean journal of agricultural research, 2012
Temperate fruit crops are an important economic activity for growers in southern Brazil. However, several pest species are associated to apple (Malus domestica Borkh.) crops in Brazil. Pesticides are largely used to control them and one way to change this is to combine selective pesticides and predator insects. The goal of this research was to evaluate the effects of the abamectin, carbaryl, fenitrothion, methidathion, sulfur, and trichlorfon pesticides on the survival and stage length of larvae and pupae, adult oviposition from treated larvae, and hatched eggs of two Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) populations. The compounds were sprayed on glass plates in accordance with the International Organization for Biological Control (IOBC) recommendations. First-and second-instar larvae were exposed to pesticide residues. Carbaryl, fenitrothion, and methidathion caused 100% mortality of first-and second-instar larvae. Changes in the number of eggs laid by females from first-and second-instar larvae exposed to residues of abamectin and sulfur, or abamectin, sulfur, and trichlorfon, respectively, were not observed. Only abamectin reduced the number of hatched eggs laid by females in Bento Gonçalves from treated first-instar larvae. Sulfur reduced the viability of C. externa eggs in Bento Gonçalves and Vacaria females from treated second-instar larvae, whereas trichlorfon and abamectin reduced the viability of eggs in Vacaria females. In conclusion, carbaryl, fenitrothion and methidathion were harmful to C. externa. Trichlorfon was harmful to first-instar larvae and slightly harmful to second-instar larvae. Abamectin and sulfur were slightly harmful to first-instar larvae and harmless to second-instar larvae.
Selectivity of Pesticides used in Integrated Apple Production to the Lacewing,Chrysoperla externa
Journal of Insect Science, 2010
This research aimed to assess the toxicity of the pesticides abamectin 18 CE (0.02 g a.i. L-1), carbaryl 480 SC (1.73 g a.i. L-1), sulfur 800 GrDA (4.8 g a.i. L-1), fenitrothion 500 CE (0.75 g a.i. L-1), methidathion 400 CE (0.4 g a.i. L-1), and trichlorfon 500 SC (1.5 g a.i. L-1) as applied in integrated apple production in Brazil on the survival, oviposition capacity, and egg viability of the lacewing, Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) from Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. An attempt was made to study morphological changes caused by some of these chemicals, by means of ultrastructural analysis, using a scanning electronic microscope. Carbaryl, fenitrothion, and methidathion caused 100% adult mortality for both populations, avoiding evaluation of pesticides' effects on predator reproductive parameters. Abamectin and sulfur also affected the survival of these individuals with mortality rates of 10% and 6.7%, respectively, for adults from Bento Gonçalves, and were harmless to those from Vacaria at the end of evaluation. Trichlorfon was also harmless to adults from both populations. No compound reduced oviposition capacity. C. externa from Vacaria presented higher reproductive potential than those from Bento Gonçalves. In relation to egg viability, sulfur was the most damaging compound to both populations of C. externa. Ultrastructural analyses showed morphological changes in the micropyle and the chorion of eggs laid by C. externa treated with either abamectin or sulfur. The treatment may have influenced the fertilization of C. externa eggs and embryonic development. Sulfur was responsible for malformations in the end region of the abdomen and genitals of treated females. When applied to adults, abamectin, sulfur, and trichlorfon were harmless, while carbaryl, fenitrothion, and methidathion were harmful, according to the IOBC classification.
Revista colombiana de entomología
The effects of six pesticides applied to the coffee crop on eggs and their consequences on the subsequent developmental stages of Chrysoperla externa (Neuroptera: Chrysopidae) were evaluated under laboratory conditions. The pesticides and water (control) were sprayed on eggs using a Potter´s tower. After spraying, forty eggs per treatment were individualized in glass tubes and maintained in a climatic chamber, in order to evaluate immature development of this predator. The treatments showed significant differences for egg viability and survival of first-instar larvae. Chlorpyrifos, sulphur and copper oxichlorate reduced the treated egg viability, whereas both sulphur and betacyfluthrin reduced the survival of first-instar larvae. Endosulphan and azociclotin reduced the daily oviposition of this green lacewing species. The harmless products (Class 1, E < 30%), can be recommended for use in integrated pest management programs in coffee crops, in order to preserve this predator.
Indian Journal of Entomology, 2012
Laboratory studies were conducted on the toxicity of Neembaan ® , imidacloprid, acetamiprid, thiamethoxam and buprofezin on larvae of Chrysoperla sp. (carnea-group). Acetamiprid was observed to be highly toxic. Based on the LC 50 , the descending order of toxicity was acetamiprid (0.005)>, thiamethoxam (0.006)>, imidacloprid (0.013)>buprofezin (0.241)> and neembaan (< 50% mortality at highest concentration). Imidacloprid at field recommended dose (0.005%) caused 26.00% mortality at 24 hours after treatment. Neembaan ® proved to be the safest whereas, buprofezin was safe and exhibited slight harmful effect at high concentration.
Neotropical Entomology, 2017
Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous plants in South America. It is considered a great threat by the European and Mediterranean Plant Protection Organization due to the serious economic damage that it causes on tomato farms; therefore, controlling this pest is a challenging task in South America. Controlling N. elegantalis at the egg stage is the best way to prevent it from damaging crops; however, thorough studies about the effectiveness of chemicals on the different life stages of this insect pest are lacking. In this study, the effects of different chemical classes were evaluated on N. elegantalis adults, female oviposition behavior, larvae, eggs, and embryonic development. None of the tested insecticides demonstrated toxicity to the adults; however, the results showed that cartap hydrochloride affects oviposition behavior. Moreover, methomyl and cartap hydrochloride exhibited high toxicity against the eggs and larvae, with higher than 80% of mortality. These insecticides interrupted larval hatching and caused alterations in the chorion layer. Flubendiamide and deltamethrin demonstrated toxicity on N. elegantalis larvae; however, lufenuron, indoxacarb, methoxyfenozide, and chlorantraniliprole demonstrated low toxicity on both eggs and larvae, with lower than 70% of mortality. Fruit treated with cartap hydrochloride had a deterrent effect. The ovicidal activity revealed by methomyl and cartap hydrochloride might provide new approaches regarding insecticide effects on eggs. Methomyl, cartap hydrochloride, flubendiamide, and deltamethrin demonstrated toxicity on larvae. The evaluation of the chorion of the eggshell in this study has clarified the toxic effect of methomyl and cartap hydrochloride on eggs.
Environmental Entomology, 2008
Chrysoperla externa (Hagen) is a generalist predator in agroecosystems. We assessed the effect of cypermethrin, endosulfan, methoxyfenozide, and spinosad on immature development time, survivorship, sex ratio, fecundity, and fertility on this organism in laboratory toxicity tests. Effects on second-generation organisms were also studied. Exposures were realized by dipping Յ24-h-old eggs in pesticide solutions at maximum Þeld recommended concentrations (MFRCs) registered in Argentina. Although no signiÞcant ovicidal effect was detected with any of the compounds, endosulfan and cypermethrin produced 96 and 100% mortality, respectively, on larvae 48 h after hatching. Spinosad caused signiÞcantly higher mortality than controls but this effect was less immediate, lasted longer and was less intense than effects with conventional insecticides. Methoxifenozide did not produce signiÞcant mortality in any stages. Spinosad and cypermethrin reduced egg development time, but no similar effects were observed with other insecticides. Methoxyfenozide inhibited the fecundity during the Þrst 24 h; however, fertility was not affected. Spinosad had no effect on fecundity or fertility of the adults. No long-term detrimental effects on the progeny were detected for spinosad and methoxyfenozide. Conventional insecticides (endosulfan and cypermethrin) were more toxic than biorationals ones when applied to eggs of C. externa. The ecotoxicological studies showed the neonate-L 1 larvae as a susceptible developmental stage. These data indicate that the biorational insecticides tested are compatible with conserving C. externa.
Environmental Entomology, 2008
Chrysoperla externa (Hagen) is a generalist predator in agroecosystems. We assessed the effect of cypermethrin, endosulfan, methoxyfenozide, and spinosad on immature development time, survivorship, sex ratio, fecundity, and fertility on this organism in laboratory toxicity tests. Effects on second-generation organisms were also studied. Exposures were realized by dipping Յ24-hold eggs in pesticide solutions at maximum Þeld recommended concentrations (MFRCs) registered in Argentina. Although no signiÞcant ovicidal effect was detected with any of the compounds, endosulfan and cypermethrin produced 96 and 100% mortality, respectively, on larvae 48 h after hatching. Spinosad caused signiÞcantly higher mortality than controls but this effect was less immediate, lasted longer and was less intense than effects with conventional insecticides. Methoxifenozide did not produce signiÞcant mortality in any stages. Spinosad and cypermethrin reduced egg development time, but no similar effects were observed with other insecticides. Methoxyfenozide inhibited the fecundity during the Þrst 24 h; however, fertility was not affected. Spinosad had no effect on fecundity or fertility of the adults. No long-term detrimental effects on the progeny were detected for spinosad and methoxyfenozide. Conventional insecticides (endosulfan and cypermethrin) were more toxic than biorationals ones when applied to eggs of C. externa. The ecotoxicological studies showed the neonate-L 1 larvae as a susceptible developmental stage. These data indicate that the biorational insecticides tested are compatible with conserving C. externa.
Ciência e Agrotecnologia, 2003
This work was designed to evaluate the residual action of the insecticides trichlorfon, triflumuron, endosulfan, fenpropathrin, chlorpirifos, tebufenozide and esfenvalerate, sprayed on cotton plants, to second-instar larvae of Chrysoperla externa (Hagen, 1861), under greenhouse conditions. The experimental design was completely randomized with ten replicates. Three larvae were released on each plant, in the 1 st , 12 th and 23 rd day after pesticides spray. Tebufenozide and esfenvalerate were little persistent (class one), while trichlorfon, triflumuron and endosulfan were slightly persistent, decreasing the survival of C. externa larvae over 30%, up to 14 days after spray. Fenpropathrin and chlorpirifos caused mortality over 30%, up to 25 days after spray, being classified as fairly persistent.