The impact of mancozeb on entomofauna communities in apple orchards.

Two Large scale field studies have been conducted to the same design in commercial apple orchards in north and south France. Mancozeb (Dithane M-45) was applied at its post-annex I use rate of 1.6 kg a.i./ha on four occasions with a spray interval of 7 days. Reference treatments of a water treated control and toxic reference of dimethoate were also included. Studies were of randomized block design with 4 replicates (4 plots of 6 adjacent rows of 8 trees, on a surface of approximately 16 x 21 m) per treatment. Leaf and canopy dwelling arthropods were sampled before and at regular intervals after application until the end of the season. A diverse range of arthropod taxa was sampled, counted and identified which enabled for an evaluation of key taxa such as predatory mites and other beneficials but also of the whole foliar dwelling arthropod community. This two level analysis allows for a thorough investigation of both direct and indirect effects of the test item on beneficial, pest and non-target arthropods and for a state of the art evaluation at the ecological community Level using ordination techniques. The findings from the two locations were highly consistent in that mancozeb applied four times at 1.6 g a.i./ha with a 7 day spray interval caused significant but short lived reductions in predatory Phytoseiid mites of >50% with rapid recovery approximately one month after application. These transient effects did not impact secondary pests such as rust mites (Eriophyoidea) and broad mites (Tarsonemidae). A wide range of arthropod taxa were investigated (229 taxa in the north and 215 taxa in the south) and consistent adverse treatment related effects were not noted for any taxa other than Phytoseiidae. At a lower rate of mancozeb representing potential off-field deposits at 3 m due to drift effects were virtually absent on predatory mites in and to all other taxa present.

Crop Protection Discovery: Is Being the First Best?

Current crop protection chemicals span an array of chemistry classes and modes of action. Typically, within each chemistry class, there are multiple chemically distinct active ingredients competing with each other for market position. In this competition, the first product to market in a new class or mode of action may or may not have an advantage depending upon a number of parameters, including relative efficacy against the target pests, pest resistance, regulatory pressures, synthetic complexity, and marketing effectiveness. The number of companies involved in the discovery of new crop protection compounds has been declining, and patenting strategies have become more sophisticated, making it more challenging to break into an existing area of chemistry. One result is new classes of chemistry tend to be smaller, making first to market more beneficial than in the past. Additionally, the first into a market with a new class of chemistry has the opportunity to set positioning and expectations.

Biological characterization of fenpicoxamid, a new fungicide with utility in cereals and other crops.

BACKGROUND: The development of novel highly efficacious fungicides that lack cross-resistance is extremely desirable. Fenpicoxamid (Inatreq™ active) possesses these characteristics and is a member of a novel picolinamide class of fungicides derived from the antifungal natural product UK-2A. RESULTS: Fenpicoxamid strongly inhibited in vitro growth of several ascomycete fungi, including Zymoseptoria tritici (EC50 , 0.051 mg L-1 ). Fenpicoxamid is converted by Z. tritici to UK-2A, a 15-fold stronger inhibitor of Z. tritici growth (EC50 , 0.0033 mg L-1 ). Strong fungicidal activity of fenpicoxamid against driver cereal diseases was confirmed in greenhouse tests, where activity on Z. tritici and Puccinia triticina matched that of fluxapyroxad. Due to its novel target site (Qi site of the respiratory cyt bc1 complex) for the cereals market, fenpicoxamid is not cross-resistant to Z. tritici isolates resistant to strobilurin and/or azole fungicides. Across multiple European field trials Z. tritici was strongly controlled (mean, 82%) by 100 g as ha-1 applications of fenpicoxamid, which demonstrated excellent residual activity. CONCLUSIONS: The novel chemistry and biochemical target site of fenpicoxamid as well as its lack of cross-resistance and strong efficacy against Z. tritici and other pathogens highlight the importance of fenpicoxamid as a new tool for controlling plant pathogenic fungi. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.