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Protecting, establishing and managing biodiverse semi-natural habitats is one strategy within the concept of ecological intensification of agriculture that supports insect pollinator abundance and diversity in agroecosystems. However, without accounting for species-level relationships between insects, crops and non-crop vegetation, diverse semi-natural habitats may not lead to improved crop pollination, and could create pest reservoirs. Possibly thousands of non-bee insect species contribute to global crop pollination, but research has largely focussed on bees. Thus, key information to best manage habitats that target wider crop pollinator diversity and abundance is lacking. We demonstrate the concept of designing mixed species native plantings (a type of semi-natural habitat) based on plant-insect interactions to increase abundance and diversity of non-bee and bee crop pollinators in an intensively managed agricultural landscape. We used existing refereed and grey literature to identify and anticipate interactions between pollinators, natural enemies and pests with native plants and crop species to design and establish plantings on three farms. We anticipated the designed plantings would support 21 pollinating species, 20 of which were verified in observational surveys 5 years post-establishment. While anticipated bee-plant species interactions were largely confirmed, actual networks of the non-bee pollinators, were larger and more complex than expected, indicating the plantings were particularly effective in supporting these interactions. Most immature life-stages of non-bee pollinators were not directly supported by plantings and separate strategies should consider larval requirements. Presenting the plant-pollinator networks to relevant industries has been a powerful tool for incentivising their support for designed habitats on farms. [ABSTRACT FROM AUTHOR]

The Japanese plum 'Black Doris' (Prunus salicina) is a self-infertile early-flowering crop so insufficient cross pollination and lack of pollinators could be factors to explain reported poor fruit set. This project assessed the relative abundance of flower visitors within a plum orchard and their movements among three orchards, as part of a wider study on plum pollination. Insect surveys conducted over three days across one orchard in 2014 identified a total of 479 individual pollinators. Honey bees represented 94.6% of all pollinators observed. To assess pollinator movement across the crop, 140 individual flower visitors were followed over a five-day period in 2014 and again in 2015 across three orchards. Bumble bees moved further within the orchard and visited more trees per minute than foraging honey bees, while silvereyes visited more than twice as many flowers per minute than any other insect flower visitor. [ABSTRACT FROM AUTHOR]

Different pollinators may vary in their temporal flower-visitation patterns within crops, potentially extending the period pollination may occur. To assess whether this could be the case in kiwifruit, we conducted standardised observational surveys of insects visiting kiwifruit flowers within 31 orchards at three times: 10:00-11:00, 12:00-13:00 and 14:00-15:00 hr. Honey bees (Apis mellifera) represented 92% of visitations (n=5474), but temporal abundances were uneven (predicted abundances were lower at 14:00-15:00 hr). Predatory hover flies (Melangyna, Melonostoma, Allograpta spp.) also showed an uneven temporal pattern. There were no significant differences in the temporal abundances for buff-tailed bumble bees (Bombus terrestris), rattailed hover flies (Eristalis, Helophilus spp.), March flies (Dilophis nigrostigma), flower longhorn beetles (Zorion guttigerum) or the native bees (Leioproctus and Lasioglossum spp.) although, in some cases, low numbers may have masked potential unevenness trends. Variation in diurnal flower-visitation patterns among insects suggests the potential for complementarity between different pollinators. [ABSTRACT FROM AUTHOR]

Insect pollination is key to ensuring adequate fruit yields within avocado orchards. Various bee and non-bee insect species have been considered as potential pollinators of avocado worldwide, but in New Zealand there has been little research into which insect species visit avocado flowers. In the Bay of Plenty, an important avocado production area, flower visitor abundance and diversity data were obtained by conducting observational surveys in four orchards in November 2015. Honey bees were the dominant flower visitors in all orchards surveyed, representing 92.9% of all insects recorded, but there was high variation in numbers among sites. Other common insects observed included the beetle, Zorion guttigerum (3.4%), and bumblebees Bombus spp. (1.6%). A better understanding of the interaction between honey bee stocking rates and flower visitor abundances within orchards could assist in improving pollination recommendations. [ABSTRACT FROM AUTHOR]

Blackleg disease caused by the fungus Leptosphaeria maculans is the most important disease of canola worldwide. The impact of this disease on the development of the Australian canola industry, particularly over the last 20 years, is discussed. Deployment of a range of disease control measures has resulted in a thriving canola industry with production now approaching 4 million tonnes annually. Discoveries about disease mechanisms and key plant and fungal genes are described. Analysis of the L. maculans genome sequence has enabled an understanding of how fungal populations can evolve rapidly to overcome disease resistance bred into canola cultivars. [ABSTRACT FROM AUTHOR]

Chelifers (Pseudoscorpions) are generalist predators of small prey such as mites. Their occasional presence in honeybee hives suggests potential to exploit them as part of a management programme against Varroa mites ( Varroa destructor), a significant pest of honeybees. Two species of native New Zealand chelifers Nesochernes gracilis and Heterochernes novaezealandiae, shown to consume Varroa mites, were collected from commercial nucleus hives or in litter surrounding the hives. Methods for mass-rearing the chelifers were developed to provide specimens for research and introduction into beehives for biological control of Varroa. Cultures were fed aphids and fruit fly larvae in vented containers containing sand and bark. N. gracilis was maintained at 14°C, 18°C, and 22°C. At 18°C, 1423 nymphs were reared from 140 N. gracilis adults, with 84.8% of all nymphs produced at this temperature. H. novaezealandiae was maintained at 18°C and 22°C, with 5 nymphs raised from 12 adults at 18°C and none at the higher temperature. [ABSTRACT FROM AUTHOR]

Many insect species can contribute to crop pollination; however, most growers remain highly dependent on the managed honey bee ( Apis mellifera L.) for this service. The European Blue Blow Fly Calliphora vicina Robineau-Desvoidy, 1830 is one species with potential use as a pollinator. It occurs worldwide and is easy to rear. Caged trials conducted within a hybrid carrot ( Daucus carota L.) seed crop found C. vicina to be an effective pollinator. Seed yield (number and weight) from field-grown carrot plants caged with C. vicina, but excluding all other large flower visitors (body width > 3 mm), was similar to seed yield from uncaged plants in the presence of honey bees ( Apis mellifera L.) and other insects. In contrast, caged plants without C. vicina produced 10-fold less seed. Under open field conditions, C. vicina spent an average of 71.0 s per umbel compared to 54.4 s for honey bees; however, under caged conditions, C. vicina spent more time on average per umbel (128.9 s). Counts of C. vicina and honey bees on umbels outside of cages and C. vicina inside cages found that honey bees were most abundant on days with maximum temperature > 25°C, while C. vicina was more abundant on cooler days around 20°C. C. vicina may therefore be a useful pollinator of crops grown in isolation cages for plant breeding purposes as well as in open fields when climatic conditions are less favourable for optimal honey bee activity. [ABSTRACT FROM AUTHOR]

The article focuses on a research conducted in order to evaluate the species diversity and abundance of small arthropods in onion, Allium cepa (A. cepa) seed fields in the New Zealand and its potential role in pollination. It discusses the use of pollinator exclusion experiments in assessing the contribution of small arthropods to A. cepa pollination. The study revealed the occurrence of insects belonging to the orders Diptera and Thysanoptera as the most abundant species.

Understanding the role of unmanaged arthropod flower visitors as crop pollinators is critical if robust and reliable long-term alternatives are to be found for honey bee pollination. However, data on pollinator assemblages can be scant. Field observation of crop flower visitors is a common data collection technique but it can be inadequate for species identification and is labour-intensive if used across many sites. Trapping may reduce this problem, but trap performance and sampling consistency over long distances (sites separated by >100 km) are rarely examined. Window traps were designed to collect flower-visiting arthropods from peak-flowering onion ( Allium cepa) and pak choi ( Brassica rapa var. chinensis) fields across several regions throughout New Zealand. Trap efficacy was evaluated by comparing trapped samples with observations of flower visiting arthropods during the same trapping period, from dawn (6:00 to 7:00 hours) through to dusk (20:00–21:00 hours) at the same locations. Similar types of larger arthropods (length ≥3 mm) were observed and trapped within both crops, with the hymenopteran genera Apidae, Colletidae and Halictidae and the dipteran families Syrphidae, Calliphoridae, Anthomyiidae, Stratiomyidae, Sarcophagidae, Bibionidae, Tachinidae and Muscidae the most commonly recorded. The total counts of these taxa across fields were strongly correlated between the two methods; however, the ratio of trapped to observed individuals could vary greatly between taxa. Trapping allowed more arthropods to be identified to the species level and also helped record more small arthropods (body length <3 mm) when compared with observation. Window traps can be effective for assessing the relative diversity of flower visitor assemblages and the abundance of specific taxa in specific cropping systems at the regional scale, but variation in trap efficiency between arthropod taxa must be assessed for a true measure of assemblage composition. [ABSTRACT FROM AUTHOR]

Canopy crane-based studies have been carried out to quantify the sets of arthropods that visit the flowers of a suite of common species of trees, palms and vines within the Cape Tribulation study area. Those Orders that increase significantly in abundance between the budding and flowering stages of inflorescences are identified, and multivariate and univariate comparisons have been made first, among coflowering plant species and second, at different seasons for the same plant species. The analysis has been repeated for both the profile of higher arthropod taxa in the samples and for the relative abundances of families of Coleoptera: one of the Orders most frequently suggested as critical in the pollination biology of Australian rainforests. In all cases significant differences are identified among species confirming that the visitor profile is a plant species-specific phenomenon. Profiles within plant species at different times also differed. At the ordinal level significant differences in visitor profiles associated with coflowering plants, were observed, variously, in Thysanoptera, Diptera, Lepidoptera, Coleoptera and Hymenoptera. Within the Coleoptera significant differences occurred in relative abundances of Scarabaeidae, Phalacridae, Latridiidae and Curculionidae. Seasonal differences in visitation to Syzygium gustavioides, Normanbya normanbyi and Calamus radicalis, reflected differences in Diptera, Lepidoptera, Homoptera, Thysanoptera, Hymenoptera and Araneida. Within the Coleoptera, the Elateridae and Curculionidae varied significantly between occasions. The various forms of flower/arthropod interaction that may be represented in these results are discussed, as are the implications for pollination. [ABSTRACT FROM AUTHOR]

Summary 1 The degree of discrimination shown by a herbivore when selecting oviposition sites has been suggested as a key factor to understanding herbivore population dynamics. Chrysophtharta bimaculata (Coleoptera: Chrysomelidae) is a primary pest of Tasmanian eucalypt forests and can cause severe defoliation. Previous work suggests that females show discrimination when selecting oviposition sites. Our aim was to test the degree of oviposition discrimination exhibited by C. bimaculata with regards to leaf toughness, a character that is critical to neonate survival. 2 We conducted an experiment examining the leaf toughness critical for neonate survival and found that significant larval mortality occurs above a toughness of 46.9 g. We also determined that the maximum toughness of leaves upon which larvae established in the field was 48.2 g, supporting the laboratory result. 3 Field surveys showed that although the majority of eggs were laid on leaves suitable for larval establishment, many eggs were laid on unsuitable, tougher leaves. However, all eggs were normally placed within 20 cm of suitable leaves and glasshouse trials demonstrated the neonates could move this distance without mortality occurring. 4 We conclude that egg batch distribution and larval performance of C. bimaculata will influence the population dynamics of C. bimaculata in two ways. Firstly, the availability of expanding/newly expanding leaves of eucalypt hosts will determine larval carrying capacity. Secondly, at a more localized level, the deposition of large numbers of egg batches on both suitable and unsuitable leaves followed by successful neonate migration increases the risk of resource depletion and poor larval development. [ABSTRACT FROM AUTHOR]

A survey of health districts in England and Wales was carried out at the end of 1984 to ascertain among other things the range of current programmes for preschool vision screening. The response rate was 81.3%. Altogether 94% of districts reported screening for both reduced visual acuity and squint; two districts screened for neither. A great variety of different types of tests were in use and screening was carried out at a variety of different ages. A high proportion of districts were screening children for reduced visual acuity in infancy, although screening tests applicable at this age have not been shown to be effective. Districts screened for squint between one and four times. Collection of routine monitoring information by districts was poor. [ABSTRACT FROM AUTHOR]

Ninety diabetic children each provided at least one 24-hour blood glucose profile at home using an impregnated filter paper strip. The mean 24-hour blood glucose level correlated significantly with urine control, height velocity, and Hb A1. The correlation coefficient for individual blood glucose values (r = 0.61) and for mean 24-hour blood glucose values (r = 0.73) repeated within 14 days showed an acceptable degree of reproducibility for the blood glucose profiles. Mean 24-hour blood glucose values fell significantly overall (11.4 to 9.8 mmol/l; 205 to 176 mg/100 ml) in 47 children who had repeated profiles more than 2 weeks apart. Unrecognised nocturnal hypoglycaemia (less than 3.0 mmol/l; 54 mg/100 ml) was found in 19% of children on twice-daily Semitard insulin. The study shows that children over age 7 years manage home blood glucose monitoring without difficulty. It shows that the results are reproducible and correlate with other indices of control, and that it provides a practical basis for the improvement of diabetic control. [ABSTRACT FROM AUTHOR]

Chelifers (Arachnida: Pseudoscorpionida), also known as pseudoscorpions, have been reported to be beneficial honeybee hive generalist pest predators for over 100 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 100 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 FROM AUTHOR]

The infection by Leptosphaeria maculans of Brassica napus cultivars with major gene resistance derived from Brassica rapa subsp. sylvestris was studied in southeastern Australia. Following the commercial release of these cultivars in Australia in 2000, plants with stem cankers were first reported in 2002 at two geographically isolated regions in South Australia and New South Wales. In 2003, this study showed that the major gene resistance had been overcome in an area of approximately 50,000 ha in South Australia and in two fields in New South Wales (0.5 and 30 ha). There was no relationship between disease severity and incidence in 2003 and the proximity to the sites where resistance breakdown occurred in 2002. At some locations, the frequency of isolates able to overcome the B. rapa subsp, sylvestris-derived resistance had increased between 2002 and 2003. Isolates cultured from canola cultivars with either B. rapa subsp, sylvestris-derived resistance or polygenic resistance showed host specificity when inoculated onto cultivars with B. rapa subsp, sylvestris-derived or polygenic resistance, respectively. The most likely cause of the resistance breakdown was the rapid increase in frequency of L. maculans isolates virulent on this particular resistance source. The selection pressure leading to this increased frequency was probably mediated by the planting of cultivars harboring the major resistance gene in the same locations for a 3-year period, and the ability of the pathogen to produce large numbers of asexual and sexual spores. [ABSTRACT FROM AUTHOR]