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Jasmonic acid (JA) is a fatty acid-derived signaling molecule that regulates a broad range of plant defense responses against herbivores and some microbial pathogens. Molecular genetic studies in Arabidopsis have established that JA also performs a critical role in anther and pollen development but is not essential for other developmental aspects of the plant's life cycle. Here, we describe the phenotypic and molecular characterization of a sterile mutant of tomato (jasmonic acid-insensitive1 [jai1]) that is defective in JA signaling. Although the mutant exhibited reduced pollen viability, sterility was caused by a defect in the maternal control of seed maturation, which was associated with the loss of accumulation of JA-regulated proteinase inhibitor proteins in reproductive tissues. jai1 plants exhibited several defense-related phenotypes, including the inability to express JA-responsive genes, severely compromised resistance to two-spotted spider mites, and abnormal development of glandular trichomes. We demonstrate that these defects are caused by the loss of function of the tomato homolog of CORONATINE-INSENSITIVE1 (COI1), an F-box protein that is required for JA-signaled processes in Arabidopsis. These findings indicate that the JA/COI1 signaling pathway regulates distinct developmental processes in different plants and suggest a role for JA in the promotion of glandular trichome-based defenses.

Behavioral and electroantennogram responses of plum curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), adults were tested for several methanolic plant extracts and organically approved insecticides. Plant extracts were evaluated for their potential as antifeedants or oviposition deterrents. These extract responses were also compared to those elicited by the non-neurotoxic, organic irritant-insecticide kaolin clay. Both sexes of plum curculio exhibited antennal response as measured by electroantennogram, which ranged from 0.2 to 1.1 mV, to plant extracts and the organic irritant/insecticide, with the greatest response to the extract of rough cocklebur, Xanthium strumarium L. (1.1 mV). No choice tests were conducted to compare feeding and oviposition by plum curculio on untreated apples or on apples treated with one of the extracts or the insecticide. The insecticide pyrethrum and extracts of X. strumarium and greater burdock, Arctium lappa L., significantly reduced feeding. Also, pyrethrum, A. lappa, Humulus lupulus L. (common hop), X. strumarium, and Verbascum songaricum Schrenk extracts completely inhibited egg deposition. In no-choice assays, the effects of kaolin clay with incorporated plant extracts on plum curculio feeding and oviposition were monitored as complementary tests. A. lappa—kaolin, H. lupulus—kaolin, and X. strumarium—kaolin mixtures significantly reduced the feeding of plum curculio compared to the control or kaolin clay alone. Each of the plant extract—kaolin mixtures evaluated, with the exception of Bifora radians Bieberstein (wild bishop), completely inhibited plum curculio oviposition as compared to controls.

Bacillus thuringiensis (B.t.) delta-endotoxins provide an alternative to chemical insecticides for controlling many species of pest insects. Recent biotechnological developments offer the promise of even greater use of B.t. toxins in genetically transformed pest-resistant crops. However, the discovery that insects can adapt to these toxins raises concerns about the long-term usefulness of B.t toxins. Several methods for managing the development of resistance to B.t toxins have been suggested, but none of these approaches offer clear advantages in all situations

Increasing restrictions on chemical pesticide use in orchards have encouraged the use of alternative strategies to control the northern strain of the plum curculio, Conotrachelus nenuphar (Herbst). Some of these strategies target larvae as they emerge from fruit, so existing models for larval emergence from fruit were evaluated for accuracy while examining the effect of multiple larvae and fruit type on emergence timing. Larval head width growth rate was established and used to gauge larval development. Larval emergence timing, quantified as degree—days (base 11.1°C), was recorded in tart cherries on trees, and emergence timing was recorded in multiple apple varieties both in cyclical field conditions and in constant laboratory conditions. Ovipositing females and fruit were isolated, so larvae in a fruit were all siblings. Adult emergences from pupation in soil were recorded in the laboratory and compared with existing model predictions. Model predictions did not accurately reflect the timing of larval or adult emergence, and future incorporation of factors that could improve models are discussed. Colder conditions and changing host fruit type had no significant effect on larval emergence timing but changing host fruit type correlated with a shorter pupation interval. Results suggested that females preferred to oviposit on multiple fruit rather than lay multiple eggs in one fruit. Higher numbers of larvae per fruit did not significantly alter the timing of first larval emergence, although more larvae per fruit resulted in a significantly longer emergence period in apples.

Behavioral and electroantennogram responses of plum curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), adults were tested for several methanolic plant extracts and organically approved insecticides. Plant extracts were evaluated for their potential as antifeedants or oviposition deterrents. These extract responses were also compared to those elicited by the non-neurotoxic, organic irritant-insecticide kaolin clay. Both sexes of plum curculio exhibited antennal response as measured by electroantennogram, which ranged from 0.2 to 1.1 mV, to plant extracts and the organic irritant/insecticide, with the greatest response to the extract of rough cocklebur, Xanthium strumarium L. (1.1 mV). No choice tests were conducted to compare feeding and oviposition by plum curculio on untreated apples or on apples treated with one of the extracts or the insecticide. The insecticide pyrethrum and extracts of X. strumarium and greater burdock, Arctium lappa L., significantly reduced feeding. Also, pyrethrum, A. lappa, Humulus lupulus L. (common hop), X. strumarium, and Verbascum songaricum Schrenk extracts completely inhibited egg deposition. In no-choice assays, the effects of kaolin clay with incorporated plant extracts on plum curculio feeding and oviposition were monitored as complementary tests. A. lappa-kaolin, H. lupulus–kaolin, and X. strumarium-kaolin mixtures significantly reduced the feeding of plum curculio compared to the control or kaolin clay alone. Each of the plant extract-kaolin mixtures evaluated, with the exception of Bifora radians Bieberstein (wild bishop), completely inhibited plum curculio oviposition as compared to controls.

This chapter reports the findings and analysis contained in a database of arthropod pesticide resistance and resistance management strategies. We also report resistance case analysis by chemical mode of action, top 20 most problematic arthropods, and decade analysis. We view this effort as the beginning of an automated era of pesticide resistance case reporting globally.

Pesticide resistance has had a substantial impact on crop production and has been an important driver of change in modern agriculture, animal production and human health. Focusing specifically on arthropods, this book provides a comprehensive review of relevant issues in pesticide resistance. Detailed listings and references to all documented reports of resistance from around the world are included.

Management of Oriental fruit moth, Grapholitha molesta (Busck), in apple using an ‘Enhanced Integrated Pest Management (IPM)’ program comprised of a hedgerow barrier, pheromone-based mating disruption and reduced-risk [non-organophosphorous (OP) or carbamate] insecticides was investigated over a 5-year period. The barrier was comprised of a planting of three rows of hybrid poplar, Populus deltoides Bartr.×Populus nigra L., one row of Italian alder, Alnus cordata L. (nectar reward), and one row of white pine, Pinus strobus L. The hedgerow completely surrounded the perimeter of the apple orchard and was treated with garlic and a low rate of pyrethroid insecticide in 4 of the 5 years. The Enhanced IPM program significantly reduced G. molesta populations as measured by moth captures in pheromone traps. Captures of G. molesta were significantly higher in apple orchards treated with OP and carbamate insecticides, ‘Conventional IPM’, and either not surrounded by the hedgerow or with the barrier present but not treated with the repellent compounds. To explain these differences in G. molesta control, and the potential non-lethal effect of hedgerow barriers on G. molesta orchard colonization, we studied the adult vertical movement in a traditional unsprayed standard apple orchard at three different heights: 0.95, 1.95 and 3.20 m, respectively. In the overwintering generation at a height of 0.95 and 1.95 m, the mean number of moths captured per sampling period was 14.64 and 14.84, respectively, and only 2.95 at 3.20 m. However, the number of individuals captured in the second and third generations was not significantly different at the three different heights. Fruit damage evaluated before ‘June drop’ closely corresponded to the distribution of moths captured during the overwintering generation. Fruit damage at a height of 1.95 and 3.20 m was 5.8 and 3.5%, respectively. These results indicated that G. molesta is a weak flyer and that hedgerow barriers exerted some influence in the colonization of the orchard by limiting the free movement of adults from the overwintering generation. Thus, hedgerow barriers seem to limit early migration and establishment of G. molesta in the orchard. This in turn may reduce the size of the following generations and makes subsequent control easier under the Enhanced IPM program.

Increasing restrictions on chemical pesticide use in orchards have encouraged the use of alternative strategies to control the northern strain of the plum curculio, Conotrachelus nenuphar (Herbst). Some of these strategies target larvae as they emerge from fruit, so existing models for larval emergence from fruit were evaluated for accuracy while examining the effect of multiple larvae and fruit type on emergence timing. Larval head width growth rate was established and used to gauge larval development. Larval emergence timing, quantified as degree-days (base 11.1 degree C), was recorded in tart cherries on trees, and emergence timing was recorded in multiple apple varieties both in cyclical field conditions and in constant laboratory conditions. Ovipositing females and fruit were isolated, so larvae in a fruit were all siblings. Adult emergences from pupation in soil were recorded in the laboratory and compared with existing model predictions. Model predictions did not accurately reflect the timing of larval or adult emergence, and future incorporation of factors that could improve models are discussed. Colder conditions and changing host fruit type had no significant effect on larval emergence timing but changing host fruit type correlated with a shorter pupation interval. Results suggested that females preferred to oviposit on multiple fruit rather than lay multiple eggs in one fruit. Higher numbers of larvae per fruit did not significantly alter the timing of first larval emergence, although more larvae per fruit resulted in a significantly longer emergence period in apples.