Fenvalerate Treatment Research Articles

Dual role of testosterone in fenvalerate-treated mice with respect to thyroid function and lipid peroxidation.

Effects of testosterone propionate (TP, 2.5 mg kg(-1) body weight) in fenvalerate-induced (120 mg kg(-1) body weight) thyroid dysfunction and lipid peroxidation were investigated in male mice. Testosterone propionate aggravated in the inhibition of hepatic type I iodothyronine 5'-monodeiodinase (5'D-I) activity, coupled with a decrease in serum triiodothyronine (T3) concentration in pesticide-treated mice. However, it could ameliorate the toxicity as indicated by decreased hepatic lipid peroxidation (LPO) with a marginal but significant increase in superoxide dismutase and catalase activities following fenvalerate treatment. While protective effects of testosterone on LPO indicated its antiperoxidative property, the decrease in 5'D-I activity could be because of the increased accumulation of fenvalerate in the tissues following TP administration.

PERSISTENCE OF INSECTICIDES IN A LOBLOLLY PINE SEED ORCHARD FOR CONTROL OF THE LEAFFOOTED PINE SEED BUG, LEPTOGLOSSUS CORCULUS (SAY) (HEMIPTERA: COREIDAE)

AbstractHigh volume sprays of azinphosmethyl, chlorpyrifos, fenvalerate, permethrin, and phosmet in various concentrations and formulations were simulated on loblolly pine (Pinus taeda L.) foliage in a pine seed orchard in northern Georgia. Persistence of these insecticides under field conditions was determined by weekly bioassays with adult leaffooted pine seed bugs [Leptoglossus corculus (Say)] and gas–liquid chromatography. Fenvalerate was the most persistent insecticide tested. In the first experiment, 0.2% AI fenvalerate caused virtually 100% seed bug mortality in bioassays through the 4th week after treatment, whereas mortality from azinphosmethyl dropped to ca. 14%. By the 6th week, mortality in the fenvalerate treatment was still 91%, even after 10.5 cm of rain. The permethrin treatments persisted for 2 weeks, then mortality declined below 40% at 3 weeks. In the second experiment, fenvalerate at 0.15% AI and 0.075% AI caused 95 and 90% mortality, respectively, after 3 weeks and 16 cm of rain, and the toxicity of the 0.038% and the 0.019% AI fenvalerate treatments lasted only 2 weeks with 12 cm rain. Permethrin in Ambush® EC at 0.2% AI had initial residues of about 150 ppm and caused ca. 84% mortality for 2 weeks with 12 cm rain. Azinphosmethyl WP at 0.2% AI had initial residues of ca. 104 ppm and persisted for 1 week. Seed bug mortality from phosmet at 0.4% AI diminished quickly after 1 week in the field.

Survival and Dispersal of Horse Flies (Diptera: Tabanidae) Feeding on Cattle Sprayed with a Sublethal Dose of Fenvalerate

A mark-recapture study was undertaken to determine the fate of tabanids feeding on cattle sprayed with a sublethal dose of fenvalerate. A total of 15,465 tabanids belonging to at least 17 species and five genera were marked individually; flies were divided equally between control and fenvalerate-sprayed bullocks. Data were summarized for the four most abundant species: Tabanus fuscicostatus Hine, T. lineola F., T. pallidescens Philip, and T. wilsoni Pechuman. The recapture rate of tabanids was 6.6% for the control and 3.4% for the fenvalerate treatment. When the proportion of flies predicted to die or be unaffected after feeding on the sprayed bullocks was considered, an estimated 75% of the flies exposed to a sublethal knockdown dose survived and attempted to seek a subsequent host. Dispersal of tabanids was not affected by treatment. The recapture data after the first day of marking was significantly delayed for tabanids that fed on fenvalerate-sprayed bullocks.

Sublethal Effects and Mortality of Tabanids (Diptera: Tabanidae) Induced by Fenvalerate Treatment of Cattle

The effect of fenvalerate spray treatments of cattle upon the feeding success and survival of tabanids was examined. There was a reduction in feeding time for tabanids feeding on treated cows ranging from 27.4 to 38.8%. There was also a 31% reduction in engorgement weight of Tabanus fuscicostatus Hine. The time that flies were allowed to feed upon fenvalerate-treated steers had no significant effect upon mortality rates or knockdown percentages.

Advantages and Disadvantages of Using Pyrethroids in Nova Scotia Apple Orchards

A commercial pest management company recorded data on use of insecticides and miticides, insect and mite densities, and insect and mite injury to fruit and foliage in 132-175 orchard blocks from 1980 to 1983. The pyrethroids permethrin and fen valerate were used mostly before bloom for control of the winter moth (WM), Operophtera brumata (L.). Fenvalerate was used, mostly after bloom, to control the spotted tentiform leafminer (TLM), Phyllonorycter blancardella (F.). In 1980, blocks in which a pyrethroid was used had lower levels of WM injury to fruit and fewer fruit stings caused by mirids (mostly Atractotomus mali (Meyer) and Camylomma verbasci (Meyer)), than did the blocks with no pyrethroid treatment (nonpyrethroid blocks). Prebloom applications of pyrethroids led to lower numbers of first- and second-generation TLM mines per leaf, whereas applications after bloom led to reduced counts of second-generation mines. In 1980 and 1983, the percentage of fruit injured by insects was lower in pyrethroid-treated blocks than in non pyrethroid blocks. In 1981, densities of insects were less frequently above their economic thresholds and fewer insecticide applications were needed in orchard blocks that had a single prebloom fen valerate treatment or prebloom plus postbloom pyrethroid treatments than in blocks with no pyrethroids the previous year. However, disadvantages were associated with pyrethroid use. Higher counts of first- or second-generation TLM mines sometimes were associated with fenvalerate or multiple pyrethroid use the previous year. Single applications of fenvalerate, multiple pyrethroid applications in one year, or applications in two successive years were associated with higher counts of the European red mite, Panonychus ulmi (Koch), and the apple rust mite, Aculus schlechtendali (Nalepa), higher levels of leaf bronzing by mites, and more frequent use of miticides. Fenvalerate was implicated more frequently than permethrin. The greater influence of fenvalerate was attributed to its greater toxicity to the predatory mite, Typhlodromus pyri Scheuten, and to its longer residual activity.

Host Plant Affects Response of Colorado Potato Beetle to a Pyrethroid Insecticide

Abstract The abundance of Colorado potato beetle (CPB) (Leptinotarsa decemlineata Say) larvae and their response to the pyrethroid insecticide fenvalerate were compared among three crop hosts, eggplant (Solanum melongena L.), potato (S. tuberosum L.), and tomato (Lycopersicon esculentum Mill.). Generally, fewer larvae were observed on tomato and eggplant than on potato. Percent reduction of CPB larval populations by fenvalerate was often greater on eggplant and potato than on tomato. Percent defoliation was greater on eggplant and potato than on tomato. Eggplant and potato yields increased as larval populations were reduced by fenvalerate, but tomato yield was unaffected by fenvalerate treatment. Chemical name used: cyano (3-phenoxyphenyl) methyl-4-chloro-α-(1-methylethyl) benzeneacetate (fenvalerate); butyl-carbityl 6-propylpiperonyl (piperonyl butoxide).

Effect of insecticides on the emergence ofTrichogramma Brasiliensis [Hymenoptera: Trichogrammatidae] from parasitized host eggs

The effect of 9 insecticides recommended for the control of cotton bollworms was studied, under laboratory conditions, on the emergence ofTrichogramma brasiliensis Ashmead from the parasitized eggs ofCorcyra cephalonica (Stainton) of different age groups. The insecticide concentrations tested were equivalent to those recommended for field application viz. phenthoate 0.14%, phosalone 0.15%, endosulfan 0.25%, permethrin 0.014%, monocrotophos 0.13%, fenvalerate 0.014%, cypermethrin 0.014%, fenitrothion 0.30% and quinalphos 0.14%, quinalphos and fenitrothion caused complete inhibition of emergence of the parasitoid from parasitized host eggs of all ages (1 to 7 days); but in general, adverse effect of insecticides on the disruption of emergence decreased with the advancement in the age of the parasitized eggs. For 1 day old parasitized host eggs, emergence ofT. brasiliensis adults varied from 33 to 57% for the remaining 7 treatments. For the 7 days old parasitized host eggs, emergence of parasitoids from the treatments with endosulfan, phosalone and phenthoate was similar to that from control. However, 46 to 59% inhibition of emergence was observed for permethrin, monocrotophos and cypermethrin. Fenvalerate treatment also significantly inhibited the emergence but at a comparatively lower level (40%). Out of 9 insecticides tested, phosalone and fenvalerate were considered to be relatively safe toT. brasiliensis.

Field evaluation and economics of insecticides against the major pests of okra

Abstract Bio‐efficacy of 15 insecticides was evaluated against the pest complex of okra in the semi‐arid region of Rajasthan during July‐October, 1984. Five sprays given at intervals of 15 days throughout the crop period indicated that fenvalerate (0.02%) was most effective, followed by permethrin (0.02%), cypermethrin (0.02%), carbaryl (0.10%), monocrotophos (0.04%) and dimethoate (0.03%), against leafhoppers, aphids and fruit borer. The maximm yield of marketable fruits was obtained with fenvalerate, followed by cypermethrin, carbaryl, monocrotophos and dimethoate treatments. Highest net‐profit of Rs. 4890.00 was also recorded with fenvalerate treatment, followed by Rs. 4430.00 with carbaryl, Rs. 4148.00 with permethrin, Rs. 3977.00 with monocrotophos and Rs. 3053.00 with dimethoate treatments. A higher benfit cost ratio was found with carbaryl (1:9.78), followed by dimethoate (1:7.85), monocrotophos (1:5.18), methyl demeton (1:5.07), fenvalerate (1:3.43) and permethrin (1:2.41). These insecticides can also be used against insect pests of other vegetable crops of the season.

Grooming behavior in response to fenvalerate treatment in pyrethroid‐resistant house flies

AbstractAt topically applied doses of fenvalerate sublethal to resistant (R) and susceptible (S) flies, R flies immediately initiated a vigorous grooming behavior which allowed them to remove as much as 13% of the topically applied dose at 24 h. On the contrary, in S flies grooming was not immediately observed because S were quickly knocked down by the pyrethroid; however, grooming was observed in S after flies recovered from knockdown. Comparisons at 24 h between R flies free to groom and those restricted from grooming indicated that 90–100% of the parent compound that was recovered from the holding vials of freely grooming flies was rubbed off while only 0–10% was excreted. Additionally, grooming significantly affected the amount of radiocarbon recovered as unpenetrated insecticide, because R flies removed a portion of the topical material and deposited it in their holding vials.RésuméNettoyage après application de doses de fenvalerate à des mouches résistantes vers le pyréthroïdeAprès application topiques de doses subléthales de fenvalerate à des mouches résistantes (R) et sensibles (S), les mouches R se nettoyent immédiatement et vigoureusement, ce qui leur permet d'éliminer jusqu'à 13% de la dose en 24 h. Au contraire chez les mouches S, ce nettoyage rapide n'a pas été observé, parce qu'elles étaient rapidement paralysées par le pyréthroïde. Cependant le nettoyage s'observe après que les mouches S aient récupéré. Des comparaisons après 24 h, entre des mouches R capables de se nettoyer et d'autres à qui l'on interdit cette activité de nettoyage indiquent que 90–100% des substances marquées au 14C, récupérées dans le récipient ayant contenu les premières, proviennent de l'élimination de l'insecticide par nettoyage et seulement 0–10% de l'excrétion de l'insecticide. De plus, le nettoyage diminue de manière significative la quantité récupérée de radiocarbone correspondant à de l'insecticide n'ayant pas pénétré dans l'insecte, parce que les mouches R enlèvent une partie du matériel et le déposent dans leur récipient.

Woolly Apple Aphid Outbreak Following Use of Fenvalerate in Apples in Canterbury, New Zealand1

Substitution of the synthetic pyrethroid, fenvalerate, for azinphosmethyl in an apple orchard spray program led to an outbreak of Eriosoma lanigerum (Hausmann) within a single season of use. Aphid colonies on water sprouts of cv ‘Cox’s Orange Pippin’ had a mean of 7.88 colonies/water sprout by Dec. 12, 1978, in the fenvalerate treated block compared with 0.08 colonies under azinphosmethyl treatment. This was due to the low toxicity of fenvalerate compared with azinphosmethyl as shown in laboratory tests: Survival of treated colonies was 77.7 and 33.4%, respectively, with fenvalerate and azinphosmethyl. A midge, Dasineura mali Kieffer, also became much more prevalent under the fenvalerate treatment with 75% of water sprouts infested by mid-February 1979 compared with 14% in the azinphosmethyl block.