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Herbicide-coated fertilizers have the potential to provide lasting control of problematic weeds while simultaneously reducing the risk of injury to cotton, thus reducing yield penalties. Therefore, research was conducted in Fayetteville and Marianna, AR, to evaluate which herbicides coated on fertilizer provide lasting control of Palmer amaranth without increased risk of cotton injury. Eight herbicides were coated onto a blend of 196 kg ha-1 of urea and 112 kg ha-1 of muriate of potash and applied at the 6- to 8-leaf growth stage over the top of cotton. In Marianna, florpyrauxifen-benzyl provided the lowest control, which was 73% averaged over 14 and 28 d after treatment (DAT). The level of control provided by florpyrauxifen-benzyl did not differ from the other treatments in Fayetteville. While some herbicide treatments did have decreased control by 28 DAT, they were still effective, providing no less than 93% control. Palmer amaranth density differed among herbicides only in Marianna, where florpyrauxifen-benzyl-treated plots had a higher weed density. None of the herbicide treatments in either of the experiments caused any adverse effects on the crop as measured by visual injury, seedcotton yield, and crop groundcover. Most of the coated fertilizer treatments provided high levels of Palmer amaranth control and demonstrated the weed management potential of this herbicide application method. These results highlight the potential of implementing herbicides that are not labeled for over-the-top postemergence applications in cotton as coated fertilizers, as this method reduces the risk of injury and yield penalties. [ABSTRACT FROM AUTHOR]

Herbicide-coated fertilizers have the potential to provide lasting control of problematic weeds while simultaneously reducing the risk of injury to cotton, thus reducing yield penalties. Therefore, research was conducted in Fayetteville and Marianna, AR, to evaluate which herbicides coated on fertilizer provide lasting control of Palmer amaranth without increased risk of cotton injury. Eight herbicides were coated onto a blend of 196 kg ha-1 of urea and 112 kg ha-1 of muriate of potash and applied at the 6- to 8-leaf growth stage over the top of cotton. In Marianna, florpyrauxifen-benzyl provided the lowest control, which was 73% averaged over 14 and 28 d after treatment (DAT). The level of control provided by florpyrauxifen-benzyl did not differ from the other treatments in Fayetteville. While some herbicide treatments did have decreased control by 28 DAT, they were still effective, providing no less than 93% control. Palmer amaranth density differed among herbicides only in Marianna, where florpyrauxifen-benzyl-treated plots had a higher weed density. None of the herbicide treatments in either of the experiments caused any adverse effects on the crop as measured by visual injury, seedcotton yield, and crop groundcover. Most of the coated fertilizer treatments provided high levels of Palmer amaranth control and demonstrated the weed management potential of this herbicide application method. These results highlight the potential of implementing herbicides that are not labeled for over-the-top postemergence applications in cotton as coated fertilizers, as this method reduces the risk of injury and yield penalties.

The control of boll weevil, Anthonomus grandis grandis Boh. relies primarily on synthetic insecticides. Although insecticides are registered to spray cotton fields against boll weevils, only a few offer satisfactory control and most have broad-spectrum action. Alternatively, spinosyns have been recommended against lepidopteran pest species in cotton and are considered comparatively of reduced risk to nontargets. The susceptibility of nine populations of boll weevil to spinosad and spinetoram was determined through dried residue on squares and cotton leaves. Furthermore, control efficacy of spinosad and spinetoram compared with the standard organophosphate malathion was determined for caged adults at two different positions within the plant canopy or treated cotton leaves after different spray intervals. Boll weevil susceptibility varied across the nine populations and tested spinosyns. The lethal concentrations (LC50s and LC90s) varied from 8.62 to 32.25 and 49.86 to 281.70 mg a.i./l for spinosad and from 2.17 to 15.36 and 8.58 to 69.36 mg a.i./l for spinetoram. The location of boll weevil within the plant canopy affected the insecticide efficacy with higher mortality when caged on upper parts rather than on lower parts of cotton plants (>85% vs <45% of control) across all three insecticides. In addition, dried residues of spinosyns resulted in adult mortality >80% until the end of the evaluation period (8 d), while the standard malathion caused only 10% at this last evaluation time. Thus, we can conclude that both spinosyns promoted prolonged adult mortality using recommended field rates compared with the standard malathion. [ABSTRACT FROM AUTHOR]

New insecticide treatment options would be beneficial for control programs for Trogoderma granarium Everts, the khapra beetle, in the United States. Two insecticides were evaluated, the Polyzone® formulation of deltamethrin and a formulation of the insect growth regulator methoprene combined with deltamethrin and the synergist piperonyl butoxide. In the test with Polyzone® deltamethrin, concrete arenas were treated with a low and high rate, and held outside, inside a shed, or inside a lab. Compared to storage in the lab, residue degradation increased slightly in the shed, and then further outside, as evidenced by greater larval survival and adult emergence. Across all environmental treatments, the high rate was more effective than the lower rate. For the combination methoprene product, the effect of food contact with treated surfaces was examined. When treating arenas with food and transferring the food to clean dishes, there was no immediate effect on larval survival, but there was a reduction in survival and emergence to the adult stage after one month. For both tests, larvae apparently often went into diapause after they were introduced onto the treatment arenas. Both treatments could be utilized in management programs if T. granarium infestations are detected.

Independent decision makers are appointed to promote trust by shielding investors from rent appropriation efforts of insiders. We conduct experiments to show how the appointment procedures for such third parties influence the trust of investors and the actual distributions of returns on investment. We find that when the third party is randomly assigned, investments significantly increase in response to positive returns on investment. Investments are similarly high when insiders select anonymous third parties. However, a simple one-sided reputation mechanism between the third party and the insider (but not the investor) diminishes trust and eliminates the benefits of a supposedly independent third party. In a second experiment we show that the trust of investors, evidenced by their investment level, surprisingly does not depend on whether the decision to delegate to an independent third party or not is taken by insiders themselves or exogenously imposed by a random device. [ABSTRACT FROM AUTHOR]

Competitive advantage is typically based on a unique nexus of firm-specific investments that creates inimitable quasi-rents. Because it is impossible to write complete contracts on how to distribute the quasi-rents, stakeholders tend to underinvest in firm-specific assets to avoid the hold-up risk. This paper empirically tests the effect of third-party ownership on specific investments. Third-party ownership assigns the rights of residual control to independent fiduciaries. We conduct variations of the trust game, in which a third party, rather than the receiver, distributes the returns on investments. A randomly chosen third party with a fixed payment induces larger investments over time although the experimental design rules out reputation building. If receivers select the third parties, this benefit vanishes. If the third party receives a reward for the appointment, investments actually decrease. Investors (unwarrantedly) fear lower back transfers in such cases. [ABSTRACT FROM AUTHOR]

O objetivo deste trabalho foi avaliar o controle de dois fluxos de emergência das plantas daninhas capim-marmelada (Brachiaria plantaginea) e capim-colchão (Digitaria horizontalis) pelo herbicida imazapic, aplicado em condição de pré-emergência, por meio de curvas de dose-resposta. O delineamento experimental foi o de blocos ao acaso, com quatro repetições; cada parcela constou de um vaso de 3 L de capacidade, preenchido com solo argiloso, acrescido de sementes de capim-marmelada e capim-colchão. Sendo D a dose recomendada do imazapic (140 g ha-1), os tratamentos foram: 4D, 2D, D, 1/2D, 1/4D, 1/8D, 1/16D e ausência do herbicida. Foram realizadas avaliações visuais de controle aos 30 e 60 dias após a infestação (DAI) e de massa seca aos 60 DAI. Após a colheita da biomassa resultante do primeiro fluxo de emergência presente nas parcelas, os vasos foram novamente semeados com as plantas daninhas e foram realizadas novas avaliações de controle aos 30 e 60 dias após reinfestação (DAR) e de massa seca aos 60 DAR. A partir dos resultados obtidos, pode-se afirmar que: o imazapic inibiu o desenvolvimento de ambas as plantas daninhas, alcançando resultados superiores a 80% de controle em todas as avaliações, para a dose recomendada, nos dois fluxos de emergência; a eficácia no controle de capim-colchão foi ligeiramente superior à do controle do capim-marmelada; e o herbicida imazapic apresentou-se como uma opção interessante para manejo dessas plantas daninhas.The objective of this work was to evaluate the control of two emergence fluxes of the weeds Brachiaria plantaginea and Digitaria horizontalis by the herbicide imazapic applied under pre-emergence conditions, by analyzing the dose-response curves. The experimental design adopted was randomized blocks, with four replicates, with each plot being a 3L capacity pot, filled with clay soil plus Brachiaria plantaginea and Digitaria horizontalis seeds. Considering D as the recommended rate of imazapic (140 g ha-1), the treatments were: 4D, 2D, D, 1/2D, 1/4D, 1/8D, 1/16D and no herbicide. Visual evaluations of control at 30 and 60 Days After Infestation (DAI) and dry weight at 60 DAI were performed. After harvest of the biomass present in the plots, resulting from the first flux, the pots were seeded again followed by control evaluations at 30 and 60 Days After Re-infestation (DAR) and dry weight at 60 DAR. The results showed that imazapic inhibited the development of both weeds, reaching results higher than 80% of control in all the evaluations for the recommended dose, in both emergence fluxes; the efficacy in the control of Digitaria horizontalis was slightly superior than the control of Brachiaria plantaginea; imazapic was presented as an interesting option for management of these weeds.

Abstract: Spotted wing drosophila, Drosophila suzukii, is an invasive insect pest that has spread into many fruit production regions of the world. Strategies to protect fruit from infestation by this insect are currently dominated by insecticide applications, so producers need information on relative efficacy and residual activity of insecticides to be able to select effective treatments. Semi-field bioassays in which highbush blueberry shoots with berries were treated then exposed to adult flies at different times after application revealed that fresh residues of organophosphate, pyrethroid, and spinosyn insecticides have strong initial activity on flies, with varying levels of residual protection against fruit infestation. An organic pyrethrum insecticide was not effective, whereas the neonicotinoid insecticide acetamiprid was found to have activity for up to five days. Rainfall after application greatly reduced the level of control achieved by some insecticides. Field-scale evaluation of conventional and organic spray programs initiated in response to capture of D. suzukii flies in monitoring traps indicated that both types of management provide significant fruit protection compared to untreated fields, with less larval detection in the conventionally-produced berries. [Copyright &y& Elsevier]

A benzoylphenyl urea insect growth regulator with the common name noviflumuron was evaluated for efficacy and residual activity on the German cockroach, Blattella germanica (L.). In laboratory studies evaluating residual activity, 0.05% noviflumuron suspension concentrate produced 100% nymphal mortality 120 d after application to steel and masonite substrates. Residual activity of noviflumuron was more variable on painted plywood substrates compared with stainless steel and masonite. In bioassay arenas, population reductions caused by noviflumuron were significantly greater than Archer and the untreated populations. After 16 wk, populations exposed to 0.05, 0.1, and 0.2% noviflumuron were reduced by 51.9 ± 19.8, 62.2 ± 6.5, and 62.6 ± 18.4%, respectively. Control cockroach populations and populations exposed to 1.3% pyriproxyfen at labeled rate (Archer, 0.61 g/m²) increased by 1,286.3 ± 125.1 and 937.2 ± 137.1%, respectively, at the end of 16 wk. A field study in multifamily housing complexes showed noviflumuron (0.2 and 0.5%) to provide 73.3 ± 8.0 and 90.6 ± 3.6% trap catch reduction at 4 wk posttreatment, respectively. There were no significant differences in the performance of noviflumuron, Maxforce FC Roach Bait Stations (0.05% [AI] fipronil), and Avert dust bait (0.05% [AI] abamectin B1). Noviflumuron shows excellent potential for use in cockroach management programs. [ABSTRACT FROM AUTHOR]

New insecticide treatment options would be beneficial for control programs for Trogoderma granarium Everts, the khapra beetle, in the United States. Two insecticides were evaluated, the Polyzone® formulation of deltamethrin and a formulation of the insect growth regulator methoprene combined with deltamethrin and the synergist piperonyl butoxide. In the test with Polyzone® deltamethrin, concrete arenas were treated with a low and high rate, and held outside, inside a shed, or inside a lab. Compared to storage in the lab, residue degradation increased slightly in the shed, and then further outside, as evidenced by greater larval survival and adult emergence. Across all environmental treatments, the high rate was more effective than the lower rate. For the combination methoprene product, the effect of food contact with treated surfaces was examined. When treating arenas with food and transferring the food to clean dishes, there was no immediate effect on larval survival, but there was a reduction in survival and emergence to the adult stage after one month. For both tests, larvae apparently often went into diapause after they were introduced onto the treatment arenas. Both treatments could be utilized in management programs if T. granarium infestations are detected. [ABSTRACT FROM AUTHOR]