W orldwide, approximately 2.5 million tons of pesticides are applied each year with a purchase price $20 billion (Pesticide News 1990). In the United States, 500,000 600 different types used annually at cost $4.1 billion, including application costs (Pimentel et al. 1991). Pesticides make significant contribution to maintaining world food production. general, dollar invested in pesticide control returns $4 crops saved. Estimates that losses pests would increase 10% if no were all; specific...

For many key agricultural pests, successful management of insecticide resistance depends not only on modifying the way that insecticides are deployed, but also reducing total number treatments applied. Both approaches benefit from a knowledge biological characteristics pests promote or may retard development resistance. whitefly Bemisia tabaci (Gennadius), these factors include haplodiploid breeding system encourages rapid selection and fixation genes, its cycle succession treated untreated...

The juvenoid compound pyriproxyfen is a potent suppressor of embryogenesis and adult formation the sweetpotato whitefly, Bemisia tabaci (Gennadius). Dipping cotton seedlings infested with 0–1-d-old eggs in 0.1 mg (AI)/liter resulted total suppression egg hatch. Older were affected to lesser extent. Exposure B. females for 48 h leaves treated 5 oviposition infertile eggs. This effect persisted an additional 2 d after transfer untreated continued, although extent, up 8 d. Treatment second...

The dynamics of resistance in the sweetpotato whitefly, Bemisia tabaci (Gennadius), to neonicotinoids acetamiprid and thiamethoxam was studied extensively cotton fields Israel during cotton-growing seasons 1999–2003. Whitefly strains were collected early late mainly three locations northern, central, southern Israel. whiteflies assayed under laboratory conditions for susceptibility neonicotinoids, as part Israeli insecticide management strategy. Selections both cross-resistance between them...

Abstract The two most widespread biotypes of Bemisia tabaci (Gennadius) in southern Europe and the Middle East are referred to as B Q-type, which morphologically indistinguishable. In this study various DNA markers have been developed, applied compared for studying genetic diversity distribution biotypes. For developing sequence characterized amplified regions (SCAR) cleaved polymorphic sequences (CAPS) techniques, single random (RAPD) fragments Q biotypes, respectively, were used. CAPS...

Emamectin is a macrocyclic lactone insecticide with low toxicity to non-target organisms and the environment, considered an important component in pest-management programmes for controlling field crop pests. It powerful compound cotton bollworm Helicoverpa armigera (Hübner). A spray concentration of 25 mg AI litre-1 resulted over 90% suppression H larvae up day 28 after treatment, while similar mortality Egyptian leafworm Spodoptera littoralis Boisduval, under same conditions, was maintained...

The inheritance of resistance to pyriproxyfen, an insect growth regulator (a juvenoid, with ovicidal and larvicidal activities), was studied in the whitefly Bemisia tabaci (Gennadius). Two parental strains, both belonging Q biotype, were assayed pyriproxyfen; a susceptible strain (ALM-1) originating from Spain pyriproxyfen-resistant one (Pyri-R) Israel. ratio between two strains approximately 7,000-fold. Concentration-mortality lines for F(1) heterozygous females reciprocal crosses (SS...

Abstract Comparative bioassays of two chloronicotinyl insecticides, acetamiprid and imidacloprid, against the whitefly Bemisia tabaci (Gennadius), using foliar systemic applications, were conducted under laboratory conditions in field trials. Under controlled conditions, ovicidal activity applications on cotton seedlings was much higher than that imidacloprid. According to LC 50 90 values, 10- 18-fold more potent Both compounds effective when applied soil adults; however, potency...

Abstract The dynamics of pyriproxyfen resistance in Bemisia tabaci (Gennadius) have been studied intensively cotton fields and greenhouses Israel. High to evolved one year after its introduction for use on flowers greenhouses, three successive applications. After ten years fields, with only application per season, a high level was observed, but rate development differed among localities. It is hypothesized that these differences reflect temporal spatial variations the availability...

Abstract The potency of novaluron on laboratory susceptible and field strains S. littoralis resembles that chlorfluazuron both compounds are about 20‐fold more potent than teflubenzuron. No appreciable resistance to or was observed in a strain Spodoptera collected from cucumber the central part Israel. On other hand, showed mild 4‐fold teflubenzuron as compared strain. A very resistant colony Bemisia tabaci pyriproxyfen (1,200‐ 2,000‐fold) no cross‐resistance novaluron. Two colonies B....

Abstract Potency and cross‐resistance of various biorational insecticides, exemplified by the whitefly Bemisia tabaci , have been studied. were exposed to juvenile hormone mimic pyriproxyfen for past 12 years resulting in an over 2,000‐fold resistance, but there was no appreciable with benzoylphenyl urea novaluron. Similarly, found between two neonicotinoids, acetamiprid imidacloprid. On other hand, a slight 5–13‐fold observed another neonicotinoid thiamethoxam. Among resistant strain B....

Journal Article Effects of Insecticides on Immature and Adult Western Flower Thrips (Thysanoptera: Thripidae) in Israel Get access S. Kontsedalov, Kontsedalov 1 1Department Entomology, ARO, Bet Dagan, Israel. Search for other works by this author on: Oxford Academic PubMed Google Scholar P. G. Weintraub, Weintraub 2 2Department Gilat Experiment Station, M.P. Negev, 85280, Ismel. A. R. Horowitz, Horowitz I. Ishaaya Economic Volume 91, Issue 5, October 1998, Pages 1067–1071,...

Abstract Despite decades of research resulting in a comprehensive understanding epicuticular wax metabolism, the function these almost ubiquitous metabolites plant–herbivore interactions remains unresolved. In this study, we examined effects CRISPR‐induced knockout mutations four Nicotiana glauca (tree tobacco) metabolism genes. These cause wide range changes composition, leading to altered with insects and snails. Three interaction classes were examined: chewing herbivory by seven...

The insect growth regulator pyriproxyfen (a juvenoid) effectively inhibits the hatching of eggs tobacco or cotton whitefly, Bemisia tabaci, as well causing pupal mortality. Since 1991, this insecticide has been one main agents for controlling B tabaci on Israeli cotton. Seasonal trends susceptibility to in field populations were monitored from June (prior treatment) through late summer at different locations Israel. After seven years use within an resistance management strategy that limits a...

Abstract Pyriproxyfen, a juvenile hormone (JH) mimic, is biorational insecticide that disrupts insect development. It one of the principal insecticides being used to control Bemisia tabaci (Gennadius) on cotton, and has many environmentally positive attributes make it compatible with integrated pest management (IPM) programs. In Israel, high level resistance pyriproxyfen been observed in several isolated regions. Here, tests were conducted establish whether temporal refuges from exposure...