A ten-year review of commercial vaccine performance for control of tick infestations on cattle

Ticks are important ectoparasites of domestic and wild animals, and tick infestations economically impact cattle production worldwide. Control of cattle tick infestations has been primarily by application of acaricides which has resulted in selection of resistant ticks and environmental pollution. Herein we discuss data from tick vaccine application in Australia, Cuba, Mexico and other Latin American countries. Commercial tick vaccines for cattle based on the Boophilus microplus Bm86 gut antigen have proven to be a feasible tick control method that offers a cost-effective, environmentally friendly alternative to the use of acaricides. Commercial tick vaccines reduced tick infestations on cattle and the intensity of acaricide usage, as well as increasing animal production and reducing transmission of some tick-borne pathogens. Although commercialization of tick vaccines has been difficult owing to previous constraints of antigen discovery, the expense of testing vaccines in cattle, and company restructuring, the success of these vaccines over the past decade has clearly demonstrated their potential as an improved method of tick control for cattle. Development of improved vaccines in the future will be greatly enhanced by new and efficient molecular technologies for antigen discovery and the urgent need for a tick control method to reduce or replace the use of acaricides, especially in regions where extensive tick resistance has occurred.     

Comparing theoretical irrigation requirement and actual irrigation for citrus in Florida

Florida ranks first in citrus production, with nearly 68% of all U.S. citrus growing in the season 2005-2006. Most of the citrus groves are located from central to south Florida, and agricultural irrigation permitting is regulated by three of Florida's five water management districts. Most of the permitting for citrus production in Highlands, Polk and Hillsborough counties is conducted by the Southwest Florida Water Management District (SWFWMD), and quantities are based on the District's AGMOD computer program. In 2003, the SWFWMD implemented new permit criteria so that permitted amounts were more representative of actual water use. This paper compares grower reported citrus irrigation water use in Highlands, Polk and Hillsborough counties from 1994 through 2005 with permitted and theoretical irrigation requirements calculated by a daily water balance. Two different sets of crop coefficients (K_c's) developed for citrus in Florida were compared in the daily soil water balance calculation of theoretical irrigation requirements. The percentage of irrigated area considered in this study ranged from 40 to 60% to simulate a range of grower practices. Meteorological data from two weather stations and additional rainfall information from 50 locations within the three counties was used in the water balance. Missing and error values in the meteorological historical record data were filled with weather generators. The multiannual average water consumption (including cold protection water use) from growers ranged from 243 (Hillsborough) to 406 mm (Highlands) and the multiannual average permitted irrigation requirement (without cold protection) ranged from 295 to 557 mm. The simulated gross irrigation requirements under different scenarios of location-K_c-wetted area were variable but mostly lower than the limits established by the district, except for some scenarios in Polk County, whose maximum simulated irrigation value reached 578 mm year⁻¹. In general, permitted limits recommended by the SWFWMD seem to be reasonable for the actual water use by growers in these counties.     

Assessing freeze-tolerance in St. Augustinegrass: temperature response and evaluation methods

Winter hardiness is a major-limiting factor for St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] grown in the transitional climatic region of the United States. Lab-based freeze tests that mimic the range of field winter survivability in St. Augustinegrass can contribute to the selection of cold hardy genotypes. This study used a whole container method, four freezing temperatures, and two data collection systems to evaluate the freezing response of nine St. Augustinegrass genotypes ranging in their winter hardiness. Results indicated ?3 and ?4 °C with average regrowth ratings of 33.6 and 17.8% respectively, were more suitable temperatures for evaluating freeze survival in St. Augustinegrass than ?5 and ?6 °C with average regrowth ratings of 0.4 and 0%, respectively. Visual ratings of surviving green tissue and regrowth were generally well correlated when evaluated over a six week period post-freeze with Pearson correlation coefficients ranging of 0.17–0.62  for ?3 °C freeze tests and 0.79–0.93 for ?4 °C freeze tests. Additionally, measurement of percent green cover using digital imaging techniques commonly utilized in turfgrass field studies were significantly correlated (0.66) with visual ratings averaged across weekly post-freeze evaluation measurements for both ?3 and ?4 °C freezing temperatures. These results provide evidence that digital imaging analyses are useful in estimating surviving green tissue and regrowth in lab-based freeze tests. This study provides additional information regarding freezing temperatures, genotype responses, and data collection methods in St. Augustinegrass, which should aid breeders in the improvement of freeze tolerance in the species.     

Volatile chemical cues guide host location and host selection by parasitic plants

The importance of plant volatiles in mediating interactions between plant species is much debated. Here, we demonstrate that the parasitic plant Cuscuta pentagona (dodder) uses volatile cues for host location. Cuscuta pentagona seedlings exhibit directed growth toward nearby tomato plants (Lycopersicon esculentum) and toward extracted tomato-plant volatiles presented in the absence of other cues. Impatiens (Impatiens wallerana) and wheat plants (Triticum aestivum) also elicit directed growth. Moreover, seedlings can distinguish tomato and wheat volatiles and preferentially grow toward the former. Several individual compounds from tomato and wheat elicit directed growth by C. pentagona, whereas one compound from wheat is repellent. These findings provide compelling evidence that volatiles mediate important ecological interactions among plant species.     

Effect of selection for pollen grain size on various traits in common bean

Summary Selection among microgametophytes usually exploits variation in pollen grain germination. Studies of variation in pollen grain size in common bean (Phaseolus vulgaris L.) suggested that selection for size might lead to changes in sporophytic traits. To determine whether microgametophytic selection based on size would affect pollen grain size in subsequent generations or sporophytic traits that were correlated with pollen grain size, pollen grains from three crosses were separated into two size categories by sieving and then used to pollinate cv. Diacol Calima. Selection resulted in changes in pollen grain diameter for pollen from F₁, F₂ and F₃ plants for all crosses. In vitro germination indicated no differences between vigor of large and small grains, but extraction and sieving reduced germinability. F₁ seed from two of the crosses with size-selected pollen varied in weight according to pollen grain size, but in subsequent generations, the effect disappeared. Both size categories of selected pollen resulted in F₂ progeny with reduced numbers of seeds per pod as compared to controls, suggesting that the size selection process may have resulted in indirect selection for traits reducing seed set. The overall results suggested that genes determining pollen grain size in bean have little or no effect on sporophytic traits such as seed size and seed yield.     

Volatile components and key odorants of fennel (Foeniculum vulgare Mill.) and thyme (Thymus vulgaris L.) oil extracts obtained by simultaneous distillation-extraction and supercritical fluid extraction

Volatile oil extracts of fennel seeds (Foeniculum vulgare Mill.) and thyme leaves (Thymus vulgaris L.) were obtained by simultaneous distillation-extraction (SDE) and supercritical fluid extraction (SFE) and analyzed by gas chromatography-mass spectrometry (GC-MS). In general, fennel oil extracted by SDE and SFE showed similar compositions, with trans-anethole, estragole, and fenchone as the main components. In contrast, thymol and p-cymene, the most abundant compounds in thyme leaves, showed big differences, with generally higher amounts of monoterpenes obtained by SDE. However, in this case, the differences between the extracts were higher. Key odorants of fennel seeds determined by gas chromatography-olfactometry (GC-O) showed similar patterns when applying SDE and SFE. trans-Anethole (anise, licorice), estragole (anise, licorice, sweet), fenchone (mint, camphor, warm), and 1-octen-3-ol (mushroom) were the most intense odor compounds detected in fennel extracts. Thymol and carvacrol, with oregano, thyme, and spicy notes, were identified as key compounds contributing to the aroma of thyme leaves.     

Distribution and habitat of Spanish populations of the subtribe Hordeineae; improved views following germplasm collecting activities

A complete study was made of 20 Spanish herbaria and of the literature concerning the regional flora of Spain in order to define the geographical limits of the different genera of the subtribe Hordeineae found in Spain. Accordingly, several expeditions were undertaken to the greater part of the Spanish mainland and its islands in order to collect samples of wild populations of the genera Hordeum L., Taeniatherum Nevski and Hordelymus Jessen. This paper, which contains information garnered from both collection activities and the study of herbaria, describes the distribution and ecological characteristics of the habitats where populations of H. bulbosum, H. secalinum, H. murinum subsp. murinum, H. murinum subsp. leporinum, H. marinum subsp. marinum, H. marinum subsp. gussoneanum, Taeniatherum caput-medusae and Hordelymus europeus grow.The bioclimatic and geographical characteristics of the populations of the different genera and species from which samples were taken during collect ing expeditions are also described.     

Are landscapes over-irrigated in Southwest Florida? A spatial�Ctemporal analysis of observed data

Monthly water billing records for eleven cities in Hillsborough County Florida were available from 2001 through 2007. Irrigation was estimated from total water use based on two different methods to estimate basic indoor water use and assumed impervious areas. Estimated irrigation use was compared with a calculated irrigation requirement by a water balance to test if homeowners were over-irrigating. Results showed that on average, the mean estimated irrigation was lower than the calculated irrigation requirements in most of the cities and years given the uncertainties in this analysis. The calculated irrigation ranged from 612 to 744 mm year⁻¹, whereas the average estimated irrigation ranged from 264 to 684 mm year⁻¹. However, there were some homeowners that greatly exceeded the calculated irrigation requirement. The estimated irrigation increased temporarily in areas under urban development, which was evidenced by built landscape expansion. Good correlation was found between the annual estimated irrigation and the annual calculated irrigation requirements, when the per capita method was used, but not between the annual estimated irrigation and the annual rainfall. Future conservation programs can use this methodology to identify users where substantial opportunity for water savings exists.     

Classification of wine and alcohol vinegar samples based on near-infrared spectroscopy. Feasibility study on the detection of adulterated vinegar samples

Near-infrared (NIR) spectroscopy was used to discriminate between wine vinegar (red or white) and alcohol vinegar. One orthogonal signal correction method (OSC) was applied on a set of 73 vinegar NIR spectra from both origins and artificial blends made in the laboratory in order to remove information unrelated to a specific chemical response (tartaric acid), which was selected due to its high discriminant ability to differentiate between wine vinegar and alcohol vinegar samples. These corrected NIR spectra, as well as raw NIR spectra and 14 physicochemical variables, were used to develop separate classification models using the potential functions method as a class-modeling technique. The aforementioned models were compared to evaluate the suitability of NIR spectroscopy as a rapid method for discriminating between vinegar origins. The transformation of vinegar NIR spectra by means of an orthogonal signal correction method prompted a notable improvement in the specificity of the constructed classification models. The classification model developed was then applied to artificial vinegar blends made in the laboratory to test its capacity to recognize adulterated vinegar samples.     

Lead dietary intake in a Spanish population (Canary Islands)

For most people diet is the main route of exposure to trace metals, so information about dietary intake is also important to assess risks to human health for these elements. The purpose of this study was to determine the levels of Pb in the foods and drinks of highest consumption in the authors' our community to estimate daily intakes of Pb for each of the seven Canary Islands. Four hundred and twenty samples were analyzed using GFAAS. The total Pb intake of the Canarian population is 72.8 microg/day, 29.12% (for a person of 70 kg body weight) of the provisional tolerable weekly intake limit of 25 microg/kg fixed by the FAO/WHO. The island that presents the highest lead intake is La Gomera, followed by Lanzarote, Tenerife, and Gran Canaria islands. These four islands present a lead dietary intake over the mean Pb intake for the whole archipelago. The islands with lower Pb intakes are La Palma and Fuerteventura, with intakes under 70 microg/day. These results have also been compared with the values found for other national and international communities.