Pest management for potatoes in Wisconsin— A pilot program

A potato integrated pest management program was conducted from 1979–82 by University of Wisconsin-Extension in two of Wisconsin’s major potato producing areas. The program utilized trained field scouts for intensive pest monitoring, and economic thresholds for pest control recommendations; also a grower fee to pay for the scouting service. The program scouted between 1360 ha and 3240 ha during 1979–1982 growing seasons on a weekly basis for pest problem development in the field and worked with approximately 50 commercial potato growers each year. In general, program participants used more fungicide applications and fewer insecticide applications than the control group. The pesticide usage pattern on potatoes by the IPM grower group supports the integrated pest management concept of ‘fine-tuning’ pesticide usage to individual fields, weather conditions and pest problems.     

Esters from Bacterial Oxidation of Olefins

Identification of esters isolated from culture fluids of bacteria growing upon terminal olefins indicates that bacteria oxidize olefins at the saturated methyl group, leaving the double bond intact. The yeast Candida lipolytica produces alpha-glycols from olefins, presumably by attacking the double bond.     

Ethane ocean on titan

It is proposed that Saturn's satellite Titan is covered by an ocean one to several kilometers deep consisting mainly of ethane. If the ocean is in thermodynamic equilibrium with an atmosphere of 3 percent (mole fraction) methane, then its composition is roughly 70 percent ethane, 25 percent methane, and 5 percent nitrogen. Photochemical models predict that ethane is the dominant end product of methane photolysis so that the evolving ocean is both the source and sink for continuing photolysis. The coexisting atmosphere is compatible with Voyager data.     

Inheritance of flowering time in six pea cultivars (Pisum sativum L.)

Summary The dates of flowering of six pea cultivars and their F₁ and F₂ generations grown under a moderate level of top-yellows virus infection were analysed by both Griffing's and Jinks' methods to assess the stability of the polygenic control of flowering period. Flowering period was shown to be under the control of an additive system with dominance for the late flowering characteristic. Some gene interaction was indicated in both analyses, mainly between the later-flowering cultivars, although tests for apparent over-dominance were insignificant. It was considered that the degree of virus infection within the experiment had little, if any, effect upon flowering times and that selections for flowering date in these circumstances should be almost as reliable as those made in a disease-free environment.Slightly increased earliness over the early parent was evident in five F₂ progenies and it appears possible to make further slight gains in earliness by selection in the present material.     

A descriptive spatial analysis of bovine tuberculosis in intensively controlled cattle farms in New Zealand

We describe the temporal and geographical distribution of confirmed cases of bovine tuberculosis (TB) in a population of cattle in the south-east of the North Island of New Zealand. Data were derived from routine TB testing conducted between 1980 and 2003 and included details for 69 farms. Four six-year periods were defined to coincide with changes in depopulation strategies against the wildlife TB reservoir, the brushtail possum Trichosurus vulpecula. For the periods 1980 to 1985 and 1986 to 1991 the median annual incidence rate of TB was 0.4 and 4.7 cases per 1000 cattle-years at risk, respectively. For the period 1992 to 2003 the median annual incidence rate of TB decreased to 1.8 cases per 1000 cattle-years at risk, coincident with the use of poisoning to control possums in the surrounding forest park (a major possum habitat area). We identified clusters of TB cases adjacent to the forest park and found no evidence of spatio-temporal interaction of TB risk among farms. Our findings support the hypothesis that possums living in the forest park are a source of bovine TB in this area and that farm-to-farm spread of disease was not an important infection mechanism.     

Hydrogen radicals, nitrogen radicals, and the production of O3 in the upper troposphere

The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected.     

Genome-wide insertional mutagenesis of Arabidopsis thaliana

Over 225,000 independent Agrobacterium transferred DNA (T-DNA) insertion events in the genome of the reference plant Arabidopsis thaliana have been created that represent near saturation of the gene space. The precise locations were determined for more than 88,000 T-DNA insertions, which resulted in the identification of mutations in more than 21,700 of the approximately 29,454 predicted Arabidopsis genes. Genome-wide analysis of the distribution of integration events revealed the existence of a large integration site bias at both the chromosome and gene levels. Insertion mutations were identified in genes that are regulated in response to the plant hormone ethylene.     

Characterization of mercury species in contaminated floodplain soils

The chemical form or speciation of mercury (Hg) in the floodplain soils of the East Fork Poplar Creek in Oak Ridge, Tennessee, a site contaminated from past industrial activity, was investigated. The speciation of Hg in the soils is an important factor in controlling the fate and effect of Hg at the site and in assessing human health and ecological risk. Application of three different sequential extraction speciation schemes indicated the Hg at the site was predominantly relatively insoluble mercuric sulfide or metallic Hg, though the relative proportions of each did not agree well between procedures. Application of X-ray and electron beam studies to site soils confirmed the presence of metacinnabar, a form of mercuric sulfide, the first known evidence of authigenic mercuric sulfide formation in soils.     

Report from the conference, ‘identifying obstacles to applying big data in agriculture’

Precision Agriculture - Data-centric technology has not undergone widespread adoption in production agriculture but could address global needs for food security and farm profitability. Participants...