Experimental closure of footpaths in a woodland national nature reserve in Scotland

Visitors' reactions to six types of path barrier were recorded both by observation and by means of a questionnaire survey. ‘Natural’ barriers such as logs or branches were not very effective. A plank with notice was the most efficient barrier, and also the type most preferred by visitors. Barbed wire was effective but disliked by visitors. Few people objected to the closure of paths. Children and bird watchers took less notice of barriers than did other categories of visitors.     

Development of a SNLP marker from the Pi-ta blast resistance gene by tri-primer PCR

The Pi-ta gene from indica introgressed into japonica rice has been used to control the blast disease caused by the fungal pathogen Magnaporthe grisea (Herbert) Barr. (anamorph Pyricularia oryzae Cav.) worldwide. A single nucleotide length polymorphism (SNLP) was identified at the intron region of the Pi-ta gene to develop a codominant Pi-ta gene marker suitable for genotyping with an automated machine. The DNA primer specific to the resistant Pi-taallele was labeled with blue dye (FAM, 6-carboxyfluorescein) as a forward primer, the DNA primer specific to the susceptible pi-ta allele was labeled with green dye (HEX, 4,7,2′,4′,5′,7′-hexachloro-6-carboxyfluorescein) as another forward primer and the DNA primer identical to both Pi-ta/pi-ta alleles was unlabeled as the reverse primer for polymerase chain reaction (PCR). Using these three primers, a 181-bp blue peak in homozygous resistant and a green peak of 182–183 bp in homozygous susceptible, and both peaks in heterozygous plants were produced by PCR. The utility of marker was verified using a segregating F₂ population, inbred cultivated lines, dominant markers and pathogenicity testing. A codominant Pi-ta marker was thus developed for effective Pi-ta assisted selection for crop improvement. Using highly homologous competitive primers for allele detection by PCR can benefit the study of genome organization of the complex locus. This revised version was published online in August 2006 with corrections to the Cover Date.     

The value of a craft brewery: On the relationship between craft breweries and property values

Recent literature and public discourse emphasize the role of craft breweries in the revitalization process of economically distressed neighborhoods across the U.S. With this, many are reporting rising property values in areas surrounding craft breweries. This research examines the impacts of craft breweries on both residential and commercial property values in a case study of Charlotte, North Carolina. Estimating a series of hedonic models which incorporate a difference‐in‐difference estimator, we find that craft breweries have a positive impact on residential property values. While many areas in close proximity to a craft brewery appear to have been associated with relatively higher price premiums even before the opening of the brewery, breweries tend to add to this premium, especially in center‐city neighborhoods. We find no significant impacts on commercial property values. These results are informative to policy makers considering revising zoning laws and other regulations in efforts to promote the growth of craft breweries and spur economic development in their local economies.     

Sources of Variation in Oat Kernel Size

Oat kernel size uniformity is important to the oat milling industry because of the size fractionations that occur in the milling process. We measured frequency of single, double, and triple kernel spikelets and kernel mass of primary, secondary, and tertiary kernels from each spikelet type (for a total of six kernel types) to determine relative influence of kernel type, panicle position, genotype, and environment on oat kernel size for 10 oat cultivars grown at four locations. Kernel type was the most important factor affecting kernel size. Primary kernels from triple kernel spikelets were larger than primary kernels from double kernel spikelets. Tertiary kernels were the smallest. Environments that produced larger kernels also produced higher frequencies of triple kernel spikelets. Some genotypes produced no triple kernel spikelets in any environment, whereas others produced varying proportions, depending on the environment. Kernels closer to the top of the panicle were larger than those near the base. The presence of tertiary kernels was neither associated with lower groat percentages nor with increased proportions of undersized kernels. Most undersized kernels were kernel types other than tertiary.     

Congruity backcrossing as a means of creating genetic variability in self pollinated crops: seed morphology of Phaseolus vulgaris L. and P. acutifolius A. Gray hybrids

Summary Seeds of early generations of three reciprocal congruity-backcross (CBC) pedigrees, developed by backcrossing Phaseolus vulgaris-P. acutifolius hybrids to each of the parent species in alternate generations, exhibited a preponderance of traits (size, shape, color, and pattern) of the cytoplasmic parent. The large size of Red Cloud (V₁), the P. vulgaris parent common to all of the pedigrees, dominated pedigrees with V₁ as the cytoplasmic parent, while the small size and rounded or square shapes of the tepary parents, wild P. acutifolius var. acutifolius PI 263590 or G400445 (A₁₉), wild P. acutifolius var. latifolius PI 406622 (A₁₀), or cultivated P. acutifolius var. latifolius Serowi PI 319443 (A₉), were the majority phenotypes when P. acutifolius was the cytoplasmic parent. Continuing through the second cycle of CBC, that is the second backcross with each of the parent species or the fourth backcross, began an amelioration of the apparent cytoplasmic effect on gene expression, as reciprocal pedigrees became more alike, usually with intermediate expression of parental traits or the appearance of new traits. The large seed size of V₁ was recovered in hybrids with P. acutifolius cytoplasm and the kidney shape of V₁ became rare in hybrids with P. vulgaris cytoplasm. Although the tepary-bean parents represented two subspecies and both cultivated and wild P. acutifolius, the three sets of reciprocal-hybrid pedigrees with P. vulgaris Red Cloud are surprisingly similar. It may be that the exotic parent used to develop a CBC pedigree should be selected more for combining ability in the interspecific cross than for specific economic traits. While the number of generations (six or more) required to produce fertile, intermediate CBC hybrids (that did not require embryo rescue) may preclude routine use of this method by practical plant breeders, the crossability of advanced hybrids with both parental species and the amount of variability apparent in advanced-hybrids progenies suggests that CBC would be valuable for maintaining exotic germplasm in immediately useful forms.     

The long-term effects of catchment liming and reduced sulphur deposition on forest soils and runoff chemistry in southwest Sweden

Whole catchment liming or forest liming has been proposed and implemented as a countermeasure to the effects of elevated sulphur deposition. Since the end of the 1980s the Swedish Forest Agency has undertaken experimental forest liming experiments in selected catchments in southern Sweden. These studies were with low doses (3 tonnes ha⁻¹) of lime (CaCO₃) and dolomite (CaMg(CO₃)₂). Data from both soil samples and stream water samples have been collected for the 16 years following treatment. The stream data has been complemented with data from untreated catchments, from the Swedish monitoring stream network. Significant differences due to treatment were seen for Ca, cation exchange capacity (CEC) and base saturation (BS) in the humus layer, none of these variables showed a statistically significant change in the mineral soil due to treatment alone. Soil samples from both the treated and untreated sites showed temporal changes in both the humus layer and the mineral soils with increases in pH, Ca and CEC and decreases in BS and Al which were independent of treatment. A combination of treatment and time, gave significant changes in BS and TA down to 10 cm in the mineral soil. In the stream water samples no statistically significant differences were observed between treated and untreated sites. Regardless of treatment, the streams exhibited a general pattern of declining concentrations of SO₄, Ca, sum of base cations (BC) and increasing acid neutralizing capacity (ANC). In summary, the application of a low dose of lime (3 tonnes ha⁻¹) did not result in significant changes in surface water chemistry in the study catchments and changes in soil chemistry were mainly restricted to the humus layer during the 16 years following treatment. The natural recovery, as a result of reductions in sulphur deposition, dominated the effects and was clearly seen in both the treated and untreated study sites. MAGIC simulations indicate that this recovery will continue in the coming decades.     

Periparturient Arterial Rupture in Mares: A Postmortem Study

There are limited reports characterizing the occurrence of rupture of uterine and other arteries associated with pregnancy in mares. Cases were retrieved from the records of horses submitted for necropsy to the University of Kentucky Veterinary Diagnostic Laboratory over a 15-year period (1993-2007). Five hundred thirteen horses were diagnosed with periparturient arterial rupture, representing 1.5% of the total equine necropsy cases. Arterial rupture was diagnosed predominately in older mares, with 78% of the horses being ≥15 years of age. Ruptures occurred most commonly during parturition but also were diagnosed before and after parturition. Additionally, during a consecutive 3-year period within this time interval, an extensive workup of cases was performed. In these 71 cases, the area of the arterial rupture was carefully dissected, and the location, size, and appearance of the arterial tear were determined. The uterine artery was the most commonly affected vessel. Although there was overlap, mares with uterine artery rupture tended to be older than those with rupture of other arteries. There was no predilection for the left or right sides, and the uterine artery rupture occurred most often in the first 20 cm from the origin.     

Homogeneous habitat can meet the discrete and varied resource requirements of hares but may set an ecological trap

In common with other farmland species, hares (Lepus spp.) are in widespread decline in agricultural landscapes due to agricultural intensification and habitat loss. We examined the importance of habitat heterogeneity to the Irish hare (Lepus timidus hibernicus) in a pastoral landscape. We used radio-tracking during nocturnal active and diurnal inactive periods throughout one year. In autumn, winter and spring, hares occupied a heterogeneous combination of improved grassland, providing food, and Juncus-dominated rough pasture, providing refuge. In summer, hares significantly increased their use of improved grassland. This homogeneous habitat can fulfil the discrete and varied resource requirements of hares for feeding and shelter at certain times of year. However, improved grassland may be a risky habitat for hares as silage harvesting occurs during their peak birthing period of late spring and early summer. We therefore posit the existence of a putative ecological trap inherent to a homogeneous habitat of perceived high value that satisfies the hares’ habitat requirements but which presents risks at a critical time of year. To test this hypothesis in relation to hare populations, work is required to provide data on differential leveret mortality between habitat types.