Abstract: Aim Campylobacteriosis is highly characterised by a strongly seasonal rate of incidence. Age is also known to be a risk factor for sporadic campylobacteriosis, but little has been done to quantify age-related rates of campylobacteriosis. This study investigates age-related incidence across countries and up to 12 years of data, as well as differences in seasonality within age groups.
Methods Graphical and statistical analysis of officially collected campylobacteriosis reports from three countries available from official websites.
Results For Australia, New Zealand and Canada, rates of campylobacteriosis show marked peaks at <4 years and 20–29 year age bands. These peaks indicate that stable age-related factors impact on campylobacteriosis epidemiology in all three countries. Seasonality is expressed differently across these age bands, and in years of extremes of incidence.
Conclusion Campylobacteriosis is highly seasonal, but overlying this is a stable age-related pattern of incidence, with two peaks approximately 20 years apart. Highest seasonal differences occur with ages between the two peaks.
Notes: See letter "Keep the focus on contaminated poultry to further curtail New Zealand's campylobacteriosis epidemic." http://www.ncbi.nlm.nih.gov/pubmed/21946979.1
Abstract: Three haplotypes of the recently discovered bacterium species “Candidatus Liberibacter solanacearum” are described and related to geographic ranges. The first two are associated with Zebra Chip/Psyllid Yellows of potatoes and other solanaceous plants, vectored by the tomato/potato psyllid Bactericera cockerelli in North and Central America and New Zealand. The third is associated with diseased carrots in Finland and vectored by the carrot psyllid Trioza apicalis. The haplotypes are described by SNPs on the 16s rRNA, 16s/23s ISR and 50s rplJ and rplL ribosomal protein genes. These SNPs are inherited as a package across the three genes. Haplotype “a” has been found primarily from Honduras and Guatemala through western Mexico to Arizona and California, and in New Zealand. Haplotype “b” is currently known from eastern Mexico and northwards through Texas to south central Washington. These haplotypes show some range overlap in Texas, Kansas and Nebraska. The haplotypes are not yet known to elicit biological differences in the plant or insect hosts. These apparently stable haplotypes suggest separate bacterial populations of long standing.
Abstract: Chelifers (Arachnida: Pseudoscorpionida), also known as pseudoscorpions, have been reported to be beneficial honeybee hive generalist pest predators for over 100Â years and are occasionally noted by beekeepers in their hives. We collected chelifers within or closely associated with beehives in New Zealand. Under video observation conditions, they predated upon varroa mites while studiously ignoring bee larvae. Varroa mites reproduce at exponential rates during the spring season, and current chemical miticides rely on single treatments aiming for at least 90% control. An alternate strategy, removal of mites at a rate matching their reproductive capacity, although mathematically obvious, fails unless a suitable biological control agent is available. Our observations build on over 100Â years of sporadic work to provide further evidence that chelifers show clear potential to be a suitable predator for varroa management in beehives. Approximately 25 chelifers can be expected to manage varroa populations in a single hive.
Abstract: AIMS: New Zealand has a very high rate of seasonal, sporadic campylobacteriosis compared to other OECD countries. Can the seasonality of New Zealand cases fit with an explanation of food-borne transmission (especially by chicken meat), and where does the fly-transmission hypothesis fit? METHODS: Analysis of seasonal campylobacteriosis reports at the District Health Board level compared to regional ambient temperatures, and chicken consumption data. Literature review particularly of food-associated disease risks and transmission routes. RESULTS: Campylobacteriosis rates in New Zealand show a national annual increase at a rate similar to chicken consumption. A drastic reduction in chicken consumption was associated with significantly reduced campylobacteriosis cases in two European countries, further strengthening the link between disease risk and chicken consumption. However, serotype analysis of the Campylobacter isolates is ambiguous regarding chicken meat itself as the major source of infection. The seasonal colonisation pattern in live chickens follows the seasonal increase in human cases. Flies are a plausible vector, associated with increasing overwintered fly foraging activity, rather than a summer increase in fly numbers. CONCLUSION: The typically sporadic rather than outbreak nature of campylobacteriosis, the disjoint between seasonal patterns of human and chicken infection, the seasonal pattern itself, and inconclusive serotype evidence indicates against chicken meat itself as the major source of infection. However, chicken consumption is a significant risk factor.
Abstract: lthough New Zealand tree plantations have traditionally been established by planting bare-root seedlings, there is now increased interest in the use of container-grown stock. Optimum container design is currently seen as one that incorporates lateral root-pruning. Size specifications for stock for planting out in New Zealand vary according to species.
Abstract: Seedlings of shining gum, Eucalyptus nitens [(Deane and Maiden) Maiden] were field planted during early summer near Christchurch, New Zealand. Half of the seedlings received 200 ml of water containing nutrients (Peters Excel at 2 g/l), applied to the soil surface around the root collar after planting. The other half received no treatment. Differences in height growth were readily apparent within 1 month and continued for the rest of the trial. Twenty-five percent of the unwatered plants died within 1 month, whereas 100% of the watered plants remained alive. The marginal increase in cost of applying water to seedlings immediately after planting should be easily justified in terms of improved seedling establishment and subsequent growth. Tree Planters' Notes 46(2):46-47; 1995.
Abstract: Root-pruning can be used to prevent root deformities typical of container-grown transplants. A combination of air- and chemical-pruning, using copper as the active component, has been used extensively in commercial practice for both forestry and horticultural transplants.
Copper root-pruning is considered to reduce tree instability after transplanting, eliminates a caged root structure, reduces the incidence of damping-off diseases and improves nursery labour productivity by making seedlings easier to extract from containers.
Chemical root-pruning products have been available, and used commercially, in South Africa since 1981. The first was Styrodip, superceded in 1990 by Plazdip which can be used on expanded polystyrene or plastic surfaces. Plazdip is currently in commercial use in Southern Africa, South America and Australasia.
Abstract: Two trials were conducted in an attempt to establish the effect of poor handling and transplanting techniques on subsequent root growth of containerised seedlings. Major root distortion was recorded where seedling root systems were transplanted with vertical pressure. Some distortion occurred after simulated poor transport conditions, even after the roots were teased straight. This source of distortion is unlikely to be the major cause of distorted roots after transplanting. Root systems were not distorted after pruning the bottom third off the root plug. It is recommended that container systems with shorter root plugs be chosen as this will help avoid the potential for transplanting-induced root deformities.
Abstract: The role of root pruning practices in containerised forestry seedling propagation is often ignored or poorly understood. Root pruning is used to reduce the incidence of potential container-induced deformities.
Typical root deformities of container-grown seedlings and methods of correcting them are reviewed. Correct practices are largely being followed by South African forest seedling propagation nurseries.
Abstract: Seaweed concentrate was applied to wheat plants either as a root drench or as a foliar spray. All seaweed treatments resulted in a marked increase in culm diameter. This increase was due mainly to an increase in cell size, especially of the vascular bundles. Seaweed concentrate also affected grain yield favourably. Similar observations resulting from other growth regulator usage and the significance of the findings are discussed.
