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The Mediterranean Fruit Fly Ceratitis capitata (Wiedemann) (Diptera, Tephriditae) is an important pest in the Mediterranean region causing severe economic losses. Currently, pyrethroids are the most common insecticides used in the control of the Medfly. However, the demand for biopesticides is growing due to the necessity to limit the use of hazardous chemical pesticides in the context of the integrated pest management. In this context, a valid alternative is the use of plant derived pesticides with a selective action against target pests and a shorter persistence in ecosystems.Among plant products, olive tree phenolic and polyphenolic compounds show potent bioactive properties as insecticides and growth regulators. The olive mill wastewater is an important source of these compounds.We are reporting here that the polyphenolic fractions of the olive mill wastewater, show ovicidal effects in terms of reduction of the hatching rate, whereas the larval development is not affected by the treatments.On the adults, we show that selected fractions induce a complete block of the fecundity of the females probably due to an induced disruption of the oogenesis.These results suggest that the polyphenolic fractions derived from the olive mill wastewater can be used as a strong natural chemosterilant against the Mediterranean Fruit fly and can be considered as a putative ovicidal agent.

In this investigation, the genotoxic properties of mestranol were examined in vitro. Human lymphocyte cultures were exposed for 72 h to mestranol at concentrations of 7.5, 15 and 30 µg/g. The genotoxic effects of the chemosterilant were assessed by numerical and structural chromosome aberrations. Mestranol induced certain genotoxic effects in human lymphocytes. There was a dose-dependent significant (p0.05) between the doses applied. Further, structural aberrations increased significantly (p The frequency of Robertsonian translocations increased significantly only in cultures treated with mestranol at concentration of 30 µg/g in comparison both with the control (p There were significant differences (p0.05).

The overpopulation of free-roaming companion animals has become the global crisis. The development and application of a suitable, effective, non-surgical approach for animal sterilization would have an enormous advantage over the current surgical method. The main purpose of this study was to develop and evaluate a novel nanomedicine-based chemosterilant for non-surgical castration of male companion animals. In this study, we first sought to investigate the testicular toxicity of different apoptosis-inducing agents. We next synthesized and characterized nano-sized particles which encapsulated the most potent testicular toxicants and evaluated in vitro sterilant properties. Our result showed that doxorubicin exhibited the highest cytotoxic activity against mouse spermatogenic cells. We therefore synthesized and characterized doxorubicin-encapsulated nanoemulsion. The negatively charged particle of doxorubicin-encapsulated nanoemulsion exhibited the anti-proliferative activity towards spermatogetic cells. Apoptosis studies revealed activation of Caspases 3 and 7 as well as annexin V expression. In addition, doxorubicin-encapsulated nanoemulsion exhibited anti-inflammatory activity in lipopolysaccharide-stimulated macrophages. Cell death was observed following treatment of isolated and cultured rat seminiferous tubules with doxorubicin-encapsulated nanoemulsion. In conclusion, nanoemulsion can be a potential carrier for prolonged release and to enhance activity of doxorubicin that may have utility in non-surgical castration of male animals.

The current study was designed to evaluate the efficacy of the male chemosterilant alpha-chlorohydrin (ACH) in the control of three Egyptian wild rodent pests (Order: Rodentia, Family: Muridae), namely; the Cairo spiny mouse, Acomys cahirinus (Desmarest, 1819) the lesser Egyptian gerbil, Gerbillus gerbillus (Olivier, 1801) and Shaw’s jird, Meriones shawi Rozet, 1833. The effect of ACH was tested by the examination of the relative weights of the reproductive organs, the sperm parameters, as well as the histological alterations in the testis and epididymis. The results of this study showed that ACH has no significant antifertility effect when given to A. cahirinus at doses of 50 mg/kg body weight for 5 days, 70 mg/kg for 4 days; to G. gerbillus at doses of 50 mg/kg for 3 days, and 60 mg/kg for 4 days; and to M. shawi at doses of 50 mg/kg for 5 days, and 80 mg/kg for 3 days. Taken together, it could be concluded that ACH has a species-specific action, and is not recommended to be used in the control of the rodent pests of the present study.

Agriculture is playing a very important role in Indian economy. Nowadays agricultural sector faces systematic annual losses due to pests and diseases. For controlling insect pests, many insecticides and pesticides are used in agriculture which are very harmful for humans. Long-term use of insecticides and pesticides in crops can produce resistance against insects and pests. Some plants have insecticidal properties; botanicals can be used as an alternative for insecticides and pesticides against insect pest and disease. They are less hazardous, biodegradable, and more effective than botanicals such as pyrethrins, rotenone, sabadilla, ryania, nicotine, linalool, and neem. Neem dust is used to control the stored grain pests and in toothpaste, soap, shampoo for nits, cosmetics, and cattle feed. Pheromones are one of the most powerful alternative approaches to control insect pests. Pheromones are natural substances that are produced by special glands in the abdomen of insects and it attracts the opposite gender of the same species. Insects produce pheromones for attracting the mate, for marking foraging routes, or to signal alarm to neighbors (e.g., aphids). Pheromones are used to control harmful insects and to attract insects to insecticide or chemosterilant baits, 92decrease the use of insecticidal practices. Light trap is used for monitoring insect populations with a view to provide early warning of the presence of pests, population dynamics of Lepidoptera and Coleoptera. Botanicals, pheromone trap, and light trap play a very important role in controlling insect pest in agriculture. It is an alternative approach against insecticides and pesticides for controlling the insect pests. It is less hazardous to human, easy to handle, and most effective in controlling insect pests.

The efficacy of four bi- and tri-cyclic sesquiterpenes, namely inuloxins A, B and C and alpha-costic acid, extracted from aerial parts of Dittrichia viscosa collected in Algeria was assessed against the cowpea seed beetle Callosobruchus maculatus. The compounds were evaluated for their effect on adult mortality, oviposition and adult emergence. Three concentrations (100, 50 and 25 mu g/ml) of each compound were tested with chickpea being used as the test plant. Complete adult mortality (100%) was achieved at only 1 day after exposure to inuloxins B and C and alpha-costic acid with LC50s less than 36 mu g/ml. Lethal concentration values (LC50) were determined as 30.4, 35.2, 31.6 and 29.4 mu g/ml, respectively, for inuloxins A, B and C and alpha-costic acid. Oviposition and F1 progeny emergence were significantly reduced (27% and 73%, respectively) after treatment with D. viscosa compounds. Our results also revealed that oviposition, adult emergence and sex ratio varied with the sex of the treated mating partner suggesting that the test compounds may have acted as male (or indirect female) chemosterilants resulting in reduced fecundity and fertility of untreated females that mated with treated males.

The effect of different concentrations of chemosterilant by leaf dip method , show reduction in fecundity 39.2 to 79%, net sterility 7.75 to 86.38% and control over reproduction 50.4 to 94.6%. Under adult feeding method, reduction in fecundity was observed 38.6 to 72.7%, net sterility 10.62 to 80.40% and control on over reproduction 47.2 to 94.0%.

Four species of tephritid fruit flies, Ceratitis capitata, Bactrocera dorsalis, B. cucurbitae, and B. latifrons were evaluated for toxic, developmental, and physiological responses to the chemosterilant lufenuron. No significant mortality of laboratory strains of the first three species was observed after their exposure up to 50 μg/mL of lufenuron in agar adult diet, whereas B. latifrons adults fed with 50 μg/mL of lufenuron in the diet caused significant mortality compared to the control. Fertility of C. capitata adults fed on 50 μg/mL lufenuronfortified diet between 7 and 12 days of age was approximately 46% of the no lufenuron control. Fertility of B. dorsalis and B. latifrons adults fed on 50 μg/mL lufenuron-incorporated diet was about 45% and 62% of the control, respectively. Lufenuron did not significantly affect fertility of B. cucurbitae adults. Lufenuron did not affect fecundity of C. capitata and B. dorsalis. Fecundity of B. cucurbitae and B. latifrons was not evaluated due to difficulty to count the eggs laid deep in the agar diet. Larvae fed on a liquid larval diet with ≤0.1 μg/mL of lufenuron were also evaluated. Pupal recovery, adult emergence, adult fliers, mating, egg hatch, and egg production of C. capitata were significantly decreased, while for B. dorsalis, pupal recovery, larval duration and adult emergence were affected. No effect of lufenuron on B. cucurbitae larvae was observed. B. latifrons was not performed because shortage of eggs at the time of this research. Lufenuron is a potential agent for management and control of C. capitata and B. dorsalis.

The current study involved evaluation of the toxicity of acetone soluble fraction of the ethanol extract of Annona squamosa Linn. seeds on Aedes albopictus (Skuse). Toxicity of fresh sample has been compared with that of solar radiated and heat treated aliquots of the same. Acute toxicity of fresh acetone fraction on adults was evident with LC 50 and LC 90 values of 15.21 and 60.38 μg/ml, respectively. Larvicidal bioassays recorded LC 50 and LC 90 values ranging from 0.44 to 5.97 and 1.64–43.36 μg/ml, respectively for different instars. Ovicidal bioassays yielded EC 50 and EC 90 values of 18.82 and 69.61 μg/ml. The study further revealed ovipositional deterrent and chemosterilant activities of the extract on the target mosquito. Bioassays using solar radiation and heat treated samples of the active fraction have showed toxicity levels similar to those of fresh sample. Chemical analysis of acetone soluble fraction of seed extract of A. squamosa has reveled ethyl oleate and iso-octyl phthalate as major components. Adulticidal, larvicidal, ovicidal, ovipositional deterrent and chemosterilant activities of the fraction on A. albopictus were proved . The investigation further confirmed stability of the active fraction on exposure to solar radiation and high temperature.

BACKGROUND: Chemosterilisation with lufenuron bait stations is a recently developed technique that is being implemented for Ceratitis capitata Wiedemann control. The aim of this work was to evaluate the chemosterilising effect of lufenuron against four economically important Latin American fruit flies species: Anastrepha ludens (Loew.), A. obliqua Macquart, A. serpentina Wiedemann and A. striata Schiner (Diptera: Tephritidae) in order to design a similar strategy for their control. RESULTS: Sexually mature adults were treated by ingestion with concentrations ranging from 0.1 to 30.0 mg g−1 of lufenuron in the diet. In addition, conspecific crosses with only one of the sexes being treated (30.0 mg g−1) were performed in order to appraise the contribution of each sex to the sterilising effect. In all cases, fecundity was not affected by the treatments, as opposed to fertility where all Anastrepha species studied were significantly affected, although to different extents. The conspecific crosses showed that treated males of A. ludens, A. obliqua and A. serpentina were not able to transmit the sterility to their respective untreated females. Only in the case of A. striata did crossing treated males with untreated females significantly reduced egg hatch. CONCLUSION: Although further investigations are required, the present results demonstrate that the use of lufenuron for controlling A. striata could be potentially viable. Copyright © 2010 Society of Chemical Industry

BACKGROUND: The chemosterilisation technique has been demonstrated to reduce the population and fruit damage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in citrus orchards. Field trials showed efficacy by reducing the fruit fly population, which was progressively achieved by continuous application of lufenuron to several generations. Different authors have suggested that field trials should be carried out in isolated or wide areas in order to reduce fruit fly intrusion and obtain best results. To this end, a wide-area trial over 3600 hectares has been under investigation in Valencia (Spain) since 2002 to validate the chemosterilisation technique against the fruit fly. The whole area was treated with 24 traps ha−1, using more than 86 000 traps in the field trial. RESULTS: A continuous decrease in fruit fly population was observed over the 4 years under trial. Moreover, results showed a significant reduction in persimmon damage in the chemosterilant treatment area compared with a malathion aerial treatment area. In the case of citrus damage, no significant differences were obtained between malathion and chemosterilant treatments. CONCLUSION: The chemosterilant method reduces Mediterranean fruit fly populations, and therefore it is a candidate treatment to replace aerial treatments with insecticides in order to suppress this pest. In addition, the efficacy of chemosterilant treatment is increasing year after year. The possibility of using this technique combined with other control methods is discussed. Copyright © 2010 Society of Chemical Industry

Du-Ter (triphenyl-tin-hydroxide) was evaluated on the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.) by adult treatment. Sterilization of male and female moths with Du-Ter was achieved by feeding and by exposure to residues deposited on a glass surface. The sterilizing effect was manifested as lowering in egg production as well as egg viability. When male moths were fed on 0.3 and 0.5% Du-Ter in 10% sucrose solution, over a period of 12 hours, and mated to untreated females, 98.8 and 99.7% sterility was obtained. However feeding of females only gave rise to 85.6 and 94.4% sterility respectively. Exposure of moths for 12 hours to residual film of Du-Ter resulted in a less degree of sterility. On the other hand, better results were obtained when males were exposed to residues and then paired to untreated moths than vice versa. The fecundity of treated females, and untreated females crossed with treated males was reduced. Longevity of both sexes was adversely affected by feeding or exposing moths to residues of the chemosterilant. Zusammenfassung Chemosterilations-Wirkungen von Du-Ter auf die Falter von Spodoptera littoralis (Boisd.) Mit dem Chemosterilant Du-Ter (Triphenyl-Zinn-Hydroxid) bei Sp. littoralis konnte eine Sterilisation von ♂♂ + ♀♀ Faltern erzielt werden. Der Effekt zeigte sich sowohl in der Verminderung der Eizahl als auch in der Lebensfahigkeit der Eier. Bei Futterung ♂♂ Falter mit 0,3–0,5% Du-Ter in 10%iger Zuckerlosung, 12 Stunden lang, wurde nach Kopulation mit unbehandelten ♀♀ 98,8 und 99,7% Sterilitat festgestellt. Dagegen wurde bei Futterung von ♀♀ nur 85,6 und 94,4% Sterilitat beobachtet. Die Darbietung von Du-Ter 12 Stunden lang in Form des Kontakts mit einem dem Zuchtgefas anhaftenden dunnen uberzug ergab einen geringen Sterilisationseffekt. Wurden dagegen ♂♂ Falter dem uberzug ausgesetzt und dann mit unbehandelten ♀♀ gepaart, verbesserten sich die Resultate. Die Fruchtbarkeit behandelter und unbehandelter ♀♀ wurde bei Paarung mit behandelten ♂♂ vermindert. Die Lebensdauer beider Geschlechter wurde durch Du-Ter-Behandlung beeintrachtigt.

Twenty-six test compounds which include 21 alkylating (14 aziridines and 7 alkyl-alkane-sulphonates), 2 thiozolium salts and 3 miscellaneous compounds (derivatives of phosphoramides and S-triazines) were studied for mortality, fertility and longevity of the pupae and adults of Trogoderma granarium Everts. The aqueous solutions of the test compounds were administered by dipping the pupae and by contact of adults with treated glass and filter paper surfaces on which film deposits were obtained as 1 mg AI/cm2. Of all the compounds tested by the above methods, thiotepa has proven to be the best chemosterilant for the pupae and adults, followed by tepa, metepa and Ent 61969 (Bis [1-aziridinyl) phosphine sulphide, amine). Zusammenfassung Versuche mit 26 Verbindungen zur Sterilisation von Trogoderma granarium Everts Von 26 Substanzen, darunter 21 Alkylverbindungen, wurde die Wirkung hinsichtlich Sterblichkeit, Fertilitat und Lebensdauer nach Behandlung der Puppen und Kafer getestet. Als am wirksamsten erwies sich Thiotepa, gefolgt von Tepa, Metepa und Ent 61969.

Spraying egg masses of Spodoptera exigua by acetone solutions of tepa, metepa, apholate and hempa at concentrations of 0.1–0.75% has no significant effect on egg viability. Better results were obtained when 5th instar larvae were topically treated with doses of 50–400 μg of aqueous solutions of the chemosterilants whereby sterility in the resulting adults increased with increase in dosage. The best effects showed tepa (85.27%). The most promising results were obtained in adult feeding treatments. When both sexes were fed separately for 24 hours on sucrose solutions treated with chemosterilants and then paired together, appreciable differences in both fecundity and fertility were observed. Complete sterility was induced in the case of tepa, metepa and apholate at concentrations as low as 0.1%. Untreated females mated with males fed 0.5% chemosterilant for 24 hours showed appreciable reduction in both egg production and percent egg viability. Complete sterility was achieved with tepa and metepa. The average egg production of treated females was greatly reduced with the 3 aziridinyl compounds. Complete sterility was obtained with tepa and metepa. Longevity of both sexes was reduced by feeding adults on chemosterilant/sucrose solutions. In all cases hempa was of a very slight effect. Zusammenfassung Laborversuche mit den Chemosterilantien Tepa, Metepa, Apholate und Hempa bei Spodoptera exigua (Hubn.) (Lep., Noctuid.) Das Bespruhen der Eigelege von S. exigua mit Acetonlosungen der genannten Chemosterilantien in Konzentrationen zwischen 0,1 und 0,75% hatte keine signifikante sterilisierende Wirkung zur Folge. Bessere Ergebnisse erbrachte die Behandlung der Raupen des 5. Stadiums mit wasrigen Losungen der Chemosterilantien in Konzentrationen zwischen 50 und 500μg: Der Prozentsatz steriler Falter nahm mit steigender Dosis zu. Die beste Wirkung zeigte Tepa (85,0%), gefolgt von Metepa (76,1%) und Apholate (53,3%). Die aussichtsreichsten Ergebnisse erbrachte die Behandlung der Falter auf dem Weg uber die Nahrungsaufnahme. Wenn beide Geschlechter 24 Stunden lang mit Zuckerlosungen gefuttert wurden, denen Chemosterilantien beigemischt waren, hatte dies eine erhebliche Beeintrachtigung ihrer Fecunditat und Fertilitat zur Folge. Vollstandige Sterilitat wurde mit Tepa, Metepa und Apholate in Konzentrationen von 0,1% und hoher erreicht. Unbehandelte Weibchen, die sich mit behandelten Mannchen paarten, erzeugten weniger Eier mit hoherer Sterblichkeit als normal gepaarte. Vollstandige Sterilitat wurde wiederum mit Tepa und Metepa erzielt. Die mittlere Eizahl behandelter Weibchen wurde durch die drei Aziridinyl-Komponenten stark vermindert, wobei Tepa und Metepa zu vollstandiger Sterilitat fuhrten. Die Lebensdauer der Falter beiden Geschlechts wurde durch Futterung mit Zucker-Chemosterilantien-Losung vermindert. In allen Fallen zeigte Hempa nur sehr geringe Wirkungen.

n-Valeramide and malonamide were tested against Aedes aegypti. Both the compounds were found to be effective on females. n-Valeramide was found to be more effective than malonamide. Fecundity was 44.6 and 46.9% in the F1 generation of treated males with treated females, by n-valeramide and malonamide respectively. Sterility induced by n-valeramide was some higher (74%) than the malonamide (70%) in parent generation of treated males with treated females. When the treated females were crossed with untreated males, the n-valeramide showed high female sterility that is 73.5% as compared to 50% sterility caused by malonamide. Inherited effect of these compounds was observed to be less in F1 and F2 generation than in P1 generation. Abnormalities in the egg and teratogeny in the larvae and adults caused by these compounds were observed. Zusammenfassung Uber die Eignung von n-Valeramid und Malonamid als Chemosterilantien Es wurden n-Valeramid und Malonamid getestet. Beide Komponenten wirkten auf ♀♀ sterilisierend, wobei n-Valeramid effektiver war als Malonamid. Die Fecunditat betrug in der F1-Generation, nachdem elterliche ♂♂ und ♀♀ behandelt waren, 44,6% bei n-Valeramid und 46,9% bei Malonamid. Die Sterilitat bei der behandelten alteren Generation war in beiden Geschlechtern etwa gleich: ♂♂ = 74%, ♀♀ = 70%. Nach Kreuzung von behandelten ♀♀ mit unbehandelten ♂♂ betrug die Sterilitat der ♀♀ Nachkommen durch n-Valeramid 73,5%, durch Malonamid 50%. Weitergehende Auswirkungen dieser Komponenten wurden bei der Eltern-Generation in starkerem Mase beobachtet als bei den F1-und F2-Nachkommen. Es wurden Abnormitaten bei Eiern, Larven und Adulten beobachtet.

The mating capacity of the male of Spodoptera was slightly decreased by male or female treatment with the chemosterilant metepa, but the decrease was much more when both adults were treated. There was no significant difference neither in male preference between treated and untreated females nor in competition between treated and untreated males. Only young sterilized females mated; 4-days old females lost their mating ability. However adult age may not be an important factor limiting the successful eradication of adults by chemosterilants since they live for about 90 days. On the other hand sterilized moths lived only for about 7 days. The average of time of copula in the different crosses was found to be 65, 69, 75 and 77 minutes for the normal, treated-female, treated-male and treated-treated crosses respectively. The differences of the first three of them are Significant. Abnormal copulations in the treated crosses were observed in which the males could not seperate from females. Zusammenfassung Wirkungen von Metepa auf das Paarungs-Verhalten von Spodoptera littoralis (Boisd.) Die Begattungs-Kapazitat der Mannchen von Spodoptera wurde nach Behandlung der Mannchen oder Weibchen mit dem Chemosterilant Metepa etwas verringert, doch war die Verringerung groser, wenn beide Geschlechter behandelt wurden. Es waren weder die Annahme von Mannchen zwischen behandelten und unbehandelten Weibchen noch die Konkurrenz zwischen behandelten und unbehandelten Mannchen signifikant verschieden. Nur junge sterilisierte Weibchen kopulierten; 4 Tage alte Weibchen verloren ihre Kopulationsfahigkeit. Jedoch braucht das Alter kein wesentlicher Begrenzungsfaktor fur eine erfolgreiche Bekampfung der Falter mit Chemosterilantien sein, da sie etwa 90 Tage lang leben. Demgegenuber betrug die Lebenszeit der sterilisierten Falter nur 7 Tage. Die mittlere Kopulationsdauer bei den verschiedenen Paarungen betrug 65, 69, 75 unci 77 min fur Normalfalter, Sterilisation des Weibchens, des Mannchens sowie beider Geschlechter. Die Unterschiede zwischen den drei ersten Formen sind signifikant. Die Paarungen behandelter Tiere waren z. T. abnorm, indem sich die Mannchen nicht mehr von den Weibchen losen konnten.

Studies were carried out to investigate the relationship between the concentrations of two chemosterilants, Apholate and Metepa on spider mites Tetranychus cinnabarinus. The pest was allowed to feed on treated cotton leaves at different levels of concentrations. High sterility was induced by both compounds, however, Apholate was found to be more effective in causing sterility, while Metepa was, less effective as a chemosterilant, and more toxic to mites, also it showed a slight phytotoxicity on cotton leaves. The two compounds induced permanent sterility and no significant recovery was recorded, except a slight increase in Metepa. The stability of Apholate on cotton leaves was much longer than Metepa. It induced sterility for a longer period than Metepa. Zusammenfassung Zur Wirkung der Chemosterilantien Apholat und Metepa auf die Spinnmilbe Tetranychus cinnabarinus Es wurden die Wirkungen von Apholat und Metepa auf Tetr. cinnabarinus untersucht. Der Schadling saugte an Blattern, die mit verschiedenen Konzentrationen der beiden Chemosterilantien behandelt waren. Von beiden Mitteln wurde ein hoher Sterilitatsanteil erzeugt, jedoch war Apholat wirksamer als Metepa, das eine erhebliche Giftwirkung auf die Milbe hatte. Die erzeugte Sterilitat war permanent. Es wurde keine signifikante Erholung beobachtet. Die Haltbarkeit auf den Blattern war bei Apholat groser, so das dieses Mittel uber eine langere Zeitspanne wirkte als Metepa.

A compound 1, 3, 7-Trimethylxanthine, was isolated from seed extract of Coffea arabica. It proved effective as a chemosterilant for Callosobruchus chinensis, causing nearly 100% sterility at a concentration of 1.5%. At similar concentration the compound had no phytotoxic effect on the crop plant Vigna mungo. Possible use of the compound for control of stored-grain pests is suggested. Zusammenfassung 1,3,7-Trimethylxanthine, ein neues Chemosterilants fur Callosobruchus chinensis (L.) (Col., Bruchidae) Das aus dem Samenextrakt von Coffea arabica isolierte 1,3,7-Trimethylxanthine erwies sich als wirksames Chemosterilants gegenuber dem Samenkafer Callosobruchus chinensis. Es verursachte bei einer Konzentration von 1,5% nahezu 100% Sterilitat. Auf die Testpflanze Vigna mungo hatte es keine phytotoxische Wirkung. Diese Verbindung durfte zur Bekampfung von Schadlingen an gespeicherten Samen aussichtsreich sein.

Evaluation of the chemosterilant Du-Ter (triphenyl-tin-hydroxide), for histological effects on mid-gut, malpighian tubules, fat tissue, and muscles of the fourth instar larvae of the cotton leafworm Spodoptera littoralis (Boisd.) was conducted by feeding treated foliage of castor bean to larvae. The histological study showed that the material caused destruction of the mid-gut tissues and muscles; while slight and partial damage occurred to the fat body and malpighian tubules. Zusammenfassung Histologische Veranderungen bei Spodoptera littoralis (Boisd.) nach Behandlung mit Du-Ter Nach Futterung der Raupen von S. littoralis mit Blattern der Castorbohne, die mit dem Chemosterilantium Du-Ter (Triphenyl-tinhydroxide) gespruht waren, zeigten sich starke Veranderungen im Mitteldarm und in den Muskeln sowie leichtere Schaden im Gewebe der Malpighi-Gefase und des Fettkorpers.

Physiological effect of thiourea on the oviposition of eggs deposited by treated azuki bean weevil was tested by the injection method. At the constant temperature of 30 °C and 75% Relative humidity with different concentrations of chemosterilant thiourea 0.05%, 0.1%, 0.5%, the number of eggs oviposited per bean decreases with increase in concentration and % reproduction control increases with increase in concentration of thiourea. Zusammenfassung Uber sterilisierende Wirkungen von Thiourea auf die Eiablage von Callasobruchus chinensis (L.) (Bruchidae: Coleoptera) bei Anwendung der Injektionsmethode Bei konstanter Temperatur (30 °C) und Luftfeuchte (75%) nahmen nach Injektion des Chemosterilants Thiourea (0.5%, 1% und 5%) die Zahl der von C. chinensis pro Bohne abgelegten Eier mit zunehmender Konzentration ab bzw. der Prozentsatz der Reproduktionsverminderung zu.

Cyclophosphamide induced changes in the ovotestis of the snail Lymnaea acuminata, the vector of the giant liverflukes Fasciola hepatica and Fasciola gigantica were studied in order to explore potential of the drug as a chemosterilant for snails. The drug caused a dose dependent reduction in the levels of DNA, RNA and proteins and the activity of the enzyme alkaline phosphatase. It increased the activity of acid phosphatase and the levels of total free amino acids in the ovotestis. While the animals showed nearly total recovery in RNA and DNA levels 7 days after termination of drug treatment, changes produced in protein, amino acid levels and phosphatase activity did not show any recovery. It appears that cyclophosphamide, while affecting its primary targets i.e. DNA and RNA, irreversibly inhibits protein synthesis through other cellular enzymes as well.

A pest management programme using the chemosterilant lufenuron against the Mediterranean fruit fly, Ceratitis capitata in Mallorca (Spain) is reported. The aim of this field trial was to monitor the reduction on C. capitata population and fruit infestation during the second and third years of an overall pest control programme. The insect growth regulator lufenuron (a phenylbenzoylurea) was placed within a Sevep device baited with the synthetic, female attractants (ammonium acetate, putrescine and amines), as well as the male attractant trimedlure (TML). A total of 7200 devices were placed on 300 ha within the municipalities of the Soller Valley, at a density of 24 devices/ha. In order to measure the effectiveness of the chemosterilization, the C. capitata population was evaluated by Probodelt traps, baited either with the synthetic food attractants or TML, placed in three citrus orchards located at different altitudes. Fruit infestation was also evaluated. Results showed an average of 20% reduction in adult medfly population (37.2% for males vs. 2.7% for females). However, high differences were observed among the different orchards. In Site 1, where fallen oranges fruits were removed and phytosanitary treatments were applied, female captures decreased by 63.28%. Whereas at Site 2, where fallen fruits were neglected and no insecticide was applied, female captures increased by 19.90%. Ceratitis capitata population increase placed in Site 2 was probably due to the presence of unmanaged or mismanaged surrounding orchards. Summing up, it seems that the method based on lufenuron applied in the Soller Valley was successful in decreasing medfly population, but the presence of the nearby improperly managed citrus orchards, as well as other hosts fruit trees for C. capitata, decrease the efficacy of the method.

[EN] Lufenuron is a chitin synthesis inhibitor, which is able to impede Mediterranean fruit fly, Ceratitis capitata (Wiedemann), reproduction. In laboratory trials, following ingestion of lufenuron, the eggs laid by female Ceratitis capitata were prevented from hatching. In field trials in Valencia, Spain, lufenuron showed its effectiveness by reducing C. capitata wild populations and its continuous application to several generations of fruit fly resulted in increased pest control. This field trial was conducted in an isolated valley some 80ha in size, over a continuous four-year period. In order to maintain the sterilizing effect in the field throughout the whole year, a new lufenuron bait gel was developed. This bait gel was introduced in to delta traps suspended in trees at a density of 24 traps ha 1, and these traps were replaced once a year during the field trial. Monitoring of the adult C. capitata population was conducted to assess the effects of the chemosterilant treatment. In the first year of treatment with sterilizing traps, a reduction of the C. capitata population was observed, indicating that the traps reduce the population right from the first generation. In the second, third and fourth years, a continuous and progressive reduction of the adult Mediterranean fruit fly population was observed. Therefore, the successive application of chemosterilization treatment has a cumulative effect on reducing the fly population year after year. Aerial treatment using malathion does not produce this cumulative effect, and consequently every year it is necessary to start again with the same number of flies as the year before. The possibility of using the chemosterilant method alone or combined with the sterile insect technique is discussed., The authors thank Stephen Skillman for helpful suggestions on the first version of the manuscript, Syngenta for supplying technical grade lufenuron, and the R&D+i Linguistic Assistance Office at the Universidad Politécnica de Valencia for their help in revising and correcting this paper. This research has been supported by ‘Fundación José y Ana Royo’, ‘Conselleria d’Agricultura Peixca i Alimentacio-GVA’ and INIA project number RTA03-103-C6.

A photo-stable juvenoid, pyriproxyfen, affected every life stage of Plutella xylostella at critical points in their development. Egg hatch was reduced by about 90% when eggs were treated at 0–1 d. Third instar larvae treated with the compound failed to pupate. At a dose of 100 ppm, supernumerary larvae were produced and most of the dead larvae showed abnormalities associated with the chimera form. Pupae formed at this higher dose were arrested in their development, and all died. Final instar larvae 7 d after treatment pupated successfully. However, adult eclosion was reduced to about 50% even at a low dose of 4 ppm. About 20% of treated pupae failed to eclose, but the rest were unaffected and eclosed normally. Following treatment of adults, egg production was reduced to 10 per female and these failed to hatch. Furthermore, adults placed in contact with pyriproxyfen in an acetone : canola oil formulation on aluminium foil produced eggs that failed to hatch, especially when eggs were at an early stage of development within the female at the time of treatment. Results indicate that a device treated with an appropriate formulation of pyriproxyfen to contaminate both sexes of P. xylostella adults and their eggs would be superior to methods of targeting larvae in control operations.

[EN] Two field trials in citrus orchards in Turis (Valencia, Spain) and Denia (Alicante, Spain) were performed in order to test the sterilant effect of the insect growth regulator lufenuron against wild medfly Ceratitis capitata (Wiedemann) populations. Two application methods for lufenuron were tested: spraying, in spots, an emulsion of lufenuron in a protein bait, and hanging delta traps that contained a proteinaceous gel with lufenuron (solid bait). The sterilant effect was measured as medfly population reduction, reduction of fruit damage in treated fields, and the number of eggs hatching in punctured fruits. In order to assess the efficacy of lufenuron treatments, we recorded results obtained from two different zones in both trial fields: an outer zone, close to untreated fields, and an inner zone, in the centre of lufenuron treated fields. We observed a minimum sterilant effect in the outer zone and a maximum sterilant effect in the inner one. The maximum sterilant effect was in the inner zone, where a reduction of medfly population of 80.4% in the sprayed field and a reduction of 77.6% in the solid bait field was observed. In addition, the greater the distance from the untreated zones of the treated orchard (inwards), the lower the fruit damage and medfly population level. In this inner zone, fruit punctured by medfly developed significantly fewer larvae (38.8%) than punctured fruits from the outer zone (68.6%). In addition, we recorded the decline in the activity of the lufenuron treatments with time. Lufenuron activity persisted in field for at least two weeks with spray applications, and for three months with bait gels. (C) 2004 Society of Chemical Industry., [ES] Se realizaron dos ensayos de campo en huertos de cítricos en Turis (Valencia, España) y Denia (Alicante, España) para probar el efecto esterilizante del regulador del crecimiento de insectos lufenurón en poblaciones silvestres de moscamed Ceratitis capitata (Wiedemann). Se probaron dos métodos de aplicación del lufenurón: pulverización en puntos, de una emulsión de lufenurón en un cebo proteico y trampas delta colgantes que contenían un gel proteico con lufenurón (cebo sólido). El efecto esterilizante se midió como la reducción de la población de moscamed, la reducción del daño de la fruta en los campos tratados y el número de huevos que eclosionan en las frutas perforadas. Para evaluar la eficacia de los tratamientos con lufenurón, se registraron los resultados obtenidos en dos zonas diferentes en ambos campos de prueba: una zona exterior, cerca de los campos no tratados, y una zona interior, en el centro de los campos tratados con lufenurón. Se observó un efecto esterilizante mínimo en la zona exterior y un efecto esterilizante máximo en la zona interior. El máximo efecto esterilizante fue en la zona interior, donde se observó una reducción de la población de mosca med del 80,4% en el campo asperjado y una reducción del 77,6% en el campo de cebo sólido. Además, cuanto mayor es la distancia de las zonas no tratadas del huerto tratado (hacia el interior), menor es el daño de la fruta y el nivel de población de moscamed. En esta zona interna, los frutos atacados por moscamed desarrollaron significativamente menos larvas (38,8%) que los frutos atacados en la zona exterior (68,6%). Además, se registró la disminución de la actividad de los tratamientos con lufenurón con el tiempo. La actividad de lufenurón persistió en el campo durante al menos dos semanas con aplicaciones de aspersión y durante tres meses con geles de cebo. (C) 2004 Society of Chemical Industry., We wish to thank Hiper-Riego and Jose Soler for lending their orchards for the field trial. Francisco Cuenca helped with the monitoring of punctured fruit. This research was funded by the Conseller´ıa de Agricultura de la Generalitat Valenciana, and Fundacion Jose y Ana Rollo. We also thank Fernando ´ Alfaro Lassala for his advice in field trial methodology

Bait stations are widely used to control Ceratitis capitata, even though the effect of intrusion from untreated areas decreases the efficacy of the technique. In this work, the edge effect of outer fruit fly populations from untreated areas and backyard orchards has been studied. For this purpose, a field trial was carried out during four years in a wide area of 10 000 ha located in Valencia (Spain). The main growing species were Prunus persica, Prunus domestica, Citrus sinensis, Citrus reticulata and Diospyros kaki. An area of 3,600 ha was treated with chemosterilant bait stations. Fruit fly populations were monitored during the 4 years of study inside and outside the treated area using Tephri-traps baited with trimedlure. A grid of 180 traps was placed in the field with an intertrap distance of 450 m. Multiple linear regression was applied to model population levels as a function of distance to untreated areas and backyards. The distance at which outer medfly populations influenced the treated wide-area population was about 1.3 km. This value reflects the distance at which a given fruit fly population is influenced by outer populations and suggests that C. capitata is able to move more than 1 km seeking for hosts. Thus, buffer areas in area-wide integrated pest management of Mediterranean fruit fly should be at least 1.3 km wide.

International audience; Insecticide-treated nets and indoor residual spray programs for malaria control are entirely dependent on pyrethroid insecticides. The ubiquitous exposure of Anopheles mosquitoes to this chemistry has selected for resistance in a number of populations. This threatens the sustainability of our most effective interventions but no operationally practicable way of resolving the problem currently exists. One innovative solution involves the co-application of a powerful chemosterilant (pyriproxyfen or PPF) to bed nets that are usually treated only with pyrethroids. Resistant mosquitoes that are unaffected by the pyrethroid component of a PPF/pyrethroid co-treatment remain vulnerable to PPF. There is a differential impact of PPF on pyrethroid-resistant and susceptible mosquitoes that is modulated by the mosquito's behavioural response at co-treated surfaces. This imposes a specific fitness cost on pyrethroid-resistant phenotypes and can reverse selection. The concept is demonstrated using a mathematical model.

Author(s): Hinds, Lyn A.; Henry, Stephen; Sharma, Sameer; Leung, Luke; Dyer, Cheryl; Mayer, Loretta | Abstract: The chemical 4-vinylcylcohexene diepoxide (VCD) induces depletion of primordial follicles in the ovaries of laboratory mice after intraperitoneal treatment and leads to infertility. We assessed the oral uptake of a range of doses of VCD by wild house mice, Mus domesticus, in captivity. In Experiment 1, female mice (n = 8 per group) were presented with a daily dose of liquid emulsion containing different concentrations of VCD in a volume equivalent to 10% body weight for 5 days in the presence of ad libitum mouse chow and water. Body weight, body condition, and general health status of the mice were assessed daily. Mice were killed 17 days after cessation of dosing. Internal organs were examined for normality and ovaries were fixed for analysis of primordial follicle populations. Over the 5-day treatment period, 95-100% of mice consumed all their daily dose of VCD emulsion. There were no effects on body weight, general activity, or alertness of the mice. Primordial follicle populations showed dose dependent but variable levels of depletion. In Experiment 2, the highest, most palatable VCD dose (300 mg VCD/kg) or a control dose was presented to mice (n = 24-30 per group), daily for 5 days. At 10 days post treatment, males were introduced for 3 breeding rounds. The numbers of pups/litter and proportions of females producing litters for each breeding round was not different between groups. In Experiment 3, male mice were presented with this same VCD dose; assessment of their reproductive status at 7 and 15 days post treatment indicated no treatment effect on testis and epididymis weights. These experiments indicate that while some follicle depletion was achieved in females with the orally delivered VCD dose, this was insufficient to affect their fertility. Further studies will require presentation of higher doses of VCD and/or extended presentation of this chemosterilant.

The chemosterilant activity of two naturally occurring napthaquinones, plumbagin from Plumbago sp. and juglone from Juglans regia has been evaluated using the red cotton bug Dysdercus koenigii. Their activity were compared with synthetic napthaquinones, menadione, two benzoquinones, 2,6-dimethyl and 2,3,6-trimethylbenzoquinone and a hydroquinone 2,6-dimethylhydroquinone. As far as the authors are aware, the present investigation is the first systematic attempt to investigate the effects of quinones on different aspects of reproduction, namely mating behaviour, fecundity and fertility. All the above types of quinones have revealed adverse effects on the reproduction of D. koenigii, which were topically treated as 1-day-old adults with different doses of the compounds depending on their 50% lethality (LD 50 ) values. Analysis of the data revealed a highly statistically significant reduction in the number of eggs, their hatching and further development up to the final instar stage. The sterility index increased with the increase in the dose of any of the above compounds and was highest when both sexes were treated. Among the natural products, juglone induced more sterilizing effects than plumbagin at 5-10 μg/insect. Menadione caused sterility at a very low dose such as 0.5 μg. Of the two benzoquinones, the dimethylbenzoquinone acted at a much lower dose.

Antifertility activity of a triterpenoid glycoside, DSS, isolated from the root of Dalbergia saxatilis was investigated in female Wistar rats of breeding age. When administered by gastric intubation at a dose rate of 200 mg kg(-1)body weight at the premating period, conception was inhibited in 71.4% of the treated animals. Fertility Index (FI) for this group was 107.82 compared with 373.5 value for control rats that received 30% aqueous Tween 20 vehicle. DSS, did not significantly alter the fertility of rats at the first and second trimesters of pregnancy but did cause a significant decrease (P

Accelerating the mortality of stoats (Mustela erminea) using biological agents, or reducing their fertility using chemosterilants or biological agents, are increasingly seen as more sustainable and more humane than trapping and poisoning. Obligate delayed implantation in fertilised female stoats of all ages allows 10–11 months for an applied biological agent or chemosterilant to interfere with gestation. Two chemosterilants (cabergoline and mifepristone) disrupt pregnancy in some species and may be effective on stoats, although they are not species‐specific and are probably more expensive than poisoning. For the longer term, more recent fertility control research has explored potentially more species‐specific options for other species based on inducing an immune response to an animal's own reproductive hormones, gametes, or products from embryos. Conception will be difficult to disrupt in stoats because females are sexually mature and are mated in the nest during a short period before they are we...

The effect of a benzyl-1,3-benzodioxole derivative (BBD), J3230 (5-propyl-1-en-3-oxy-6[1-(4-methyoxyphenyl)ethyl]-1,3-benzodioxole) on reproduction of the oriental fruit fly, Bactrocera dorsalis (Hendel), was investigated by exposing late 3rd instars to topsoil treated with this chemosterilant. Adult emergence and subsequent egg hatch were significantly reduced. J3230 affected primarily the reproduction of male oriental fruit fly when the mature larvae were exposed to treated soil. When untreated females were mated with males that had emerged from treated soil, the subsequent egg hatch was decreased. This decrease was retained longer with increasing J3230 concentrations. The number of spermatozoa in spermathecae of females mated with males that had emerged from treated soil was significantly reduced. Histological sections further showed aberrant flagella and sperm bundles in testes from the treated group. J3230 activity was reduced when the treated soil was incubated at 25, 35, and 45°C for extended periods; however, its activity could be retained in the soil for > 1 mo at 25 and 35°C. Short-wave length UV light (254 nm) and soil moisture were also found to affect the activity of this chemosterilant.