Efficacy of zeta-cypermethrin as pour-on or spray formulations for the control of buffalo fly (Haematobia irritans exigua) in cattle

Objective To determine the efficacy of zeta-cypermethrin in controlling buffalo fly ( Haematobia irritans exigua ).
Design Five field trials in northern and central Queensland.
Procedure Zeta-cypermethrin pour-on at 2.5 mg/kg, spray at 62.5 ppm, deltamethrin pour-on and pour-on vehicle were applied to groups of 20 cattle. Buffalo fly counts were conducted three times before treatment and 3, 7, 14, 21, 28 and 35 days after treatment.
Results In central Queensland where synthetic pyrethroid resistance in buffalo fly populations was rare, 2.5 mg/kg of zeta-cypermethrin pour-on gave good control of buffalo fly for 4 weeks and was better than a deltamethrin product. A zeta-cypermethrin spray used at 62.5 ppm gave 14 days control. In far-north Queensland where resistance to synthetic pyrethroids and heavy rain was common, the maximum period of efficacy of zeta-cypermethrin pour-on was reduced to 2 weeks.
Conclusion In areas where there is low resistance to synthetic pyrethroids among buffalo flies, zeta-cypermethrin pour-on can be expected to give good control for 4 weeks.     

Assessing the integrated pest management practices of southeastern US ornamental nursery operations

BACKGROUND: The Southern Nursery Integrated Pest Management (SNIPM) working group surveyed ornamental nursery crop growers in the southeastern United States to determine their pest management practices. Respondents answered questions about monitoring practices for insects, diseases and weeds, prevention techniques, intervention decisions, concerns about IPM and educational opportunities. Survey respondents were categorized into three groups based on IPM knowledge and pest management practices adopted. RESULTS: The three groups differed in the use of standardized sampling plans for scouting pests, in monitoring techniques, e.g. sticky cards, phenology and growing degree days, in record‐keeping, in the use of spot‐spraying and in the number of samples sent to a diagnostic clinic for identification and management recommendation. CONCLUSIONS: Stronger emphasis is needed on deliberate scouting techniques and tools to monitor pest populations to provide earlier pest detection and greater flexibility of management options. Most respondents thought that IPM was effective and beneficial for both the environment and employees, but had concerns about the ability of natural enemies to control insect pests, and about the availability and effectiveness of alternatives to chemical controls. Research and field demonstration is needed for selecting appropriate natural enemies for augmentative biological control. Two groups utilized cooperative extension almost exclusively, which would be an avenue for educating those respondents. Copyright © 2012 Society of Chemical Industry     

Detrital Zircon Link Between Headwaters and Terminus of the Upper Triassic Chinle-Dockum Paleoriver System

New detrital-zircon geochronologic data reveal that a through-going paleoriver connected Texas with Nevada in Late Triassic time. Sandstone from the Upper Triassic Santa Rosa Sandstone (Dockum Group) from northwestern Texas contains a detrital zircon suite nearly identical to that found in western Nevada in the Upper Triassic Osobb Formation (Auld Lang Syne Group, correlative with the Chinle Formation). The Santa Rosa Sandstone was derived in large part from the eroded Cambrian core of the Amarillo-Wichita uplift, as evidenced by abundant zircons with ages of 515 to 525 million years. Other zircon grains in the sandstone are Permian, Devonian, Proterozoic, and Archean in age and, with the exception of the Archean grain, are also matched by the population in the Nevada strata.     

Comparison of different inoculating methods to evaluate the pathogenicity and virulence of Aspergillus niger on two maize hybrids

A two-year field study was conducted to determine the effects of artificial inoculation techniques on the pathogenicity and virulence of Aspergillus niger kernel infection on two maize hybrids. Test plants included in the study were hybrids resistant and susceptible to Aspergillus flavus to determine if the host resistance mechanisms that limited A. flavus infection would also suppress A. niger infection. Ears were inoculated with the silk-channel, side-needle, and spray techniques 7?days after midsilk (50% of the plants in a plot had silk emerging). Ears were also inoculated with a modified-pinbar technique 21?days after midsilk. Kernel infection in 2008 in inoculated plants ranged from 2% to 11% and from 2% to 45% in the resistant and susceptible hybrids, respectively. In 2009, kernel infection in inoculated plants ranged from 13% to 32% and from 10% to 67% in the resistant and susceptible, respectively. The silk-channel, side-needle, and modified-pinbar techniques produced significantly higher levels of kernel infection in the susceptible hybrid in both years than the spray technique. When hybrids were compared, the silk-channel, side-needle, and modified-pinbar techniques induced significantly higher levels of infections in the susceptible hybrid than in the resistant hybrid in 2008 and 2009. The level of A. niger pathogenicity and virulence increased when conidia were placed inside the husks of developing ears by wounding (modified-pinbar and side-needle techniques) or non-wounding (silk-channel technique) inoculation methods. Although A. niger kernel infection was significantly lower in the A. flavus resistant hybrid compared to the A. flavus susceptible hybrid, A. niger infection levels were much higher than A. flavus infection levels typically observed in both of these hybrids in past studies.     

Effect of Wheat Moisture Content on Meal Apparent Particle Size and Hardness Scores Determined by Near-Infrared Reflectance Spectroscopy

The AACC Approved Method for near-infrared reflectance (NIR) spectroscopy to produce a wheat hardness score for wheat market classification can be corrected for variation in wheat moisture content. The cause of the variation in NIR spectra resulting from variation in wheat moisture was investigated. Ten samples each of soft red winter, soft white winter, hard red winter, and hard red spring wheats were stored at 20, 40, 60, and 80 equilibrium relative humidity. Wheats were then ground on a cyclone grinder as required by the standard method. Variation in unground wheat kernel moisture content resulted in variation in NIR data. NIR log 1/reflectance values increased at all wavelengths as wheat moisture content increased. Spectral changes were related to changes in the apparent particle size of ground wheat meal as it was influenced by moisture content. Higher moisture contents produced slightly higher apparent particle size in meal, suggesting larger particles of pericarp that became more pliable at higher moisture (temper) levels. The apparent particle size of meal of high moisture wheats resulted in greater NIR radiation scattering and decreased reflectance. Meal moisture content itself had no effect on the two NIR wavelengths used to evaluate wheat hardness.     

Assessment of organoleptic postmortem inspection techniques for bovine offal

Objective To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys.
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns.     

Diallel analysis for aflatoxin accumulation and fall armyworm leaf-feeding damage in maize

Two major impediments to profitable maize, Zea mays L., production in the southern United States are from feeding by fall armyworm, Spodoptera frugiperda (J.E. Smith), and losses from the production and accumulation of aflatoxin in maize grain. A diallel cross was produced by making all possible crosses among five germplasm lines developed as sources of resistance to fall armyworm leaf feeding and five lines developed as sources of resistance to aflatoxin accumulation. For resistance to both leaf feeding and aflatoxin accumulation, general combining ability (GCA) was a significant source of variation. Specific combining ability (SCA) was significant for fall armyworm feeding only. Estimates of GCA effects for reduced aflatoxin accumulation were significant for Mp715 and Mp719, two lines selected for resistance to aflatoxin accumulation. The GCA effects for reduced fall armyworm damage were significant for all five lines selected for fall armyworm resistance: Mp707, Mp708, Mp713, Mp714, and Mp716.     

Optimal Geometries for the Development of Rice Quality Spectroscopic Chemometric Models

Three sample geometries, two different instrument types, and two spectral collection modes (reflectance and transmission) were used to assess rice quality and develop chemometric models for composition and sensory characteristics. Rice samples (120) including three cultivars, two growing locations, five drying treatments, two moisture levels, and two levels of milling were scanned in two locations. Data collected for modeling included amylose, protein, moisture, whiteness, transparency, and milling degree. Taste and texture were determined with the use of separate trained sensory panels. The NIR models show that composition is best modeled in the 1,100–2,500 nm range, while the physical properties of whiteness, transparency and milling degree are best modeled in the 750–1,050 nm range. Additional models were developed using limited data subsets of the spectral data points. In some cases, adequate models were generated with as few as 20 wavelength data points. Results show that no one spectroscopic protocol is best for all analytes in rice and that for any complex food matrix more than one preprocessing or spectral range protocol is needed.