Droplet size classification of air induction flat fan nozzles

Measurements were made of the droplet size for a series of air induction flat fan nozzles produced by Marian Mikołajczak Agro Technology (MMAT) and Coorstek. The MMAT nozzles, according to International Organization for Standardization (ISO) standard sizes, are typical single jet (long body, 37 mm) with 025, 03, and 04 orifice sizes; (short body, 21 mm) with 02, 025, 03 and 04 orifice sizes; and twin jet (short body, 21 mm) with 03 and 04 orifice sizes. Ceramic air induction flat fan nozzles of the Albuz AVI series (Coorstek, France) with the orifice size 01, 02 and 03 were tested. The sprays were described using the following droplet size parameters: D, D , D, relative span (RS), spray volume (%) in size fractions < 100 μm and 100÷200 μm. The sprays were also classified according to American Society of Agricultural Engineers (ASAE) standard S572.1 (ASAE 2009)

A Comparison of an Unhooded and Hooded Sprayer for Pesticide Drift Reduction

Management of drift from pesticide applications is important for human and environmental health concerns. It is also necessary to ensure adequate dosage of the pesticide meets the target species(s). A variety of factors can affect the drift potential of a pesticide application, including nozzle selection, solution chemistry, and application equipment. In the present study, a comparison of two ground sprayers, one with a hood and one without a hood, is made using three common ground nozzles in the US. The hooded sprayer reduced the drift potential of the pesticide application for all nozzles tested. In addition, higher spray coverage under the boom was measured when using the hooded sprayer. The results of this study indicate that incorporating a hood will lead to reduced drift potential from a pesticide application

Corn Disease Update

Goss\u27s Bacterial Wilt and Blight ... Symptoms ... Management ... 2011 Survey ... Literature Cited Gray Leaf Spot Seedling Diseases and Stalk/Crown Root Diseases More Resource

Corn Disease Update

Goss\u27s Bacterial Wilt and Blight ... Symptoms ... 2011 Survey results ... New alternate hosts identified ... Goss\u27s Wilt Management Strategies ... More Resources ... Literature Cited Aspergillus Ear Rot and Aflatoxin Contaminated Grain ... Table 1. FDA Action Levels for Aflatoxin in Feed and Food ... Testing for Aflatoxin ... High risk factors for aflatoxin contamination in corn ... Scouting for Aspergillus Ear Rot ... Harvest and Storage ... More Resources Stalk Rot Diseases ... Scouting for Stalk Rot Diseases ... Management ... More Resource

Western corn rootworm pyrethroid resistance confirmed by aerial application simulations of commercial insecticides

The western corn rootworm (Diabrotica virgifera virgifera LeConte) (WCR) is a major insect pest of corn (Zea mays L.) in the United States (US) and is highly adaptable to multiple management tactics. A low level of WCR field-evolved resistance to pyrethroid insecticides has been confirmed in the US western Corn Belt by laboratory dose-response bioassays. Further investigation has identified detoxification enzymes as a potential part of the WCR resistance mechanism, which could affect the performance of insecticides that are structurally related to pyrethroids, such as organophosphates. Thus, the responses of pyrethroid-resistant and -susceptible WCR populations to the commonly used pyrethroid bifenthrin and organophosphate dimethoate were compared in active ingredient bioassays. Results revealed a relatively low level of WCR resistance to both active ingredients. Therefore, a simulated aerial application bioassay technique was developed to evaluate how the estimated resistance levels would affect performance of registered rates of formulated products. The simulated aerial application technique confirmed pyrethroid resistance to formulated rates of bifenthrin whereas formulated dimethoate provided optimal control. Results suggest that the relationship between levels of resistance observed in dose-response bioassays and actual efficacy of formulated product needs to be further explored to understand the practical implications of resistance

Four Common \u3ci\u3eSetaria\u3c/i\u3e Species Are Alternative Hosts for \u3ci\u3eClavibacter michiganensis\u3c/i\u3e subsp. \u3ci\u3enebraskensis\u3c/i\u3e, Causal Agent of Goss\u27s Bacterial Wilt and Blight of Corn

Goss’s bacterial wilt and blight, caused by Clavibacter michiganensis subsp. nebraskensis (Cmn), has reemerged as an important disease of Zea mays (corn) in the U.S. Midwest. Results from a 2011 multistate survey indicated that Setaria spp. (foxtail) were often present in corn fields with a history of Cmn. The objective of this research was to determine if Setaria spp. that are common in the Midwest are susceptible to infection by Cmn. In the greenhouse, seedlings of four Setaria spp., including S. viridis (green foxtail), S. faberi (giant foxtail), S. verticillata (bristly foxtail), and S. pumila (yellow foxtail), and Zea mays (Golden Cross Bantam sweet corn, GCB) were inoculated with a suspension of 1.0 × 107 bacteria cells. The trial was arranged in a randomized complete block design and repeated once. Percent of symptomatic leaf area was visually estimated eight days after inoculation. S. faberi exhibited the highest levels of disease among the four Setaria spp., with disease incidence similar to what was observed on Z. mays. S. viridis was the next most susceptible. Symptoms were also observed on S. viridis, S. verticillata, and were lowest for S. pumila. Bacterial streaming was confirmed microscopically and Cmn was reisolated from the four Setaria species. Results indicate that these four Setaria spp. are susceptible to Cmn, thus serving as potential sources of inoculum

Comparison of water-sensitive paper, Kromekote and Mylar collectors for droplet deposition with a visible fluorescent dye solution

The study was conducted at the University of Nebraska Pesticide Application and Tech-nology Laboratory in North Platte, Nebraska in July 2015. Two application volume rates (100 and 200 l · ha−1) and three nozzle types (XR, AIXR, TTI) were selected at two flow rates (0.8 and 1.6 l · min−1) and at a single application speed of 7.7 km · h−1. Each collec-tor type [Mylar washed (MW), Mylar image analysis (MIA), water-sensitive paper (WSP), and Kromekote (KK)] was arranged in a randomized complete block design. Each nozzle treatment was replicated twice, providing six cards of each collector type for each nozzle treatment. A water + 0.4% v/v Rhodamine WT spray solution was applied, given the fluo-rescent and visible qualities of Rhodamine, which allows it to be applied over all the collec-tor types. MW had the highest coverage at 18.3% across nozzle type, followed by WSP at 18%, KK at 12% and lastly by MIA at 4%. MW resulted in a 58% increase in coverage, WSP in a 56% increase, and KK only an increase of 39% when the volume rate was doubled from 100 l · ha−1 to 200 l · ha−1 across nozzle type. MW coverage was similar to KK for half of the nozzles (XR 11002, XR 11004, AIXR 11002). Droplet number density fixed effects were all significant for nozzle type and collector type (p \u3c 0.001) as was the interaction of nozzle type and collector type (p \u3c 0.001). Results from this study suggest a strong correlation to data produced with WSP and MW collectors, as there was full agreement between both types except for the TTI 11004. Using both collector types in the same study would allow for a visual understanding of the distribution of the spray, while also giving an idea of the concentration of that distribution