Beetle’s responses to edges in fragmented landscapes are driven by adjacent farmland use,season and cross-habitat movement

Context

Farming practices influence the degree of contrast between adjoining habitats, with consequences for biodiversity and species movement. Little is known, however, on insect community responses to different kinds of edges over time, and the extent of cross-habitat movement in agricultural landscapes.

Objective

To determine temporal changes in beetle responses to different farmland-woodland edges, and document cross-habitat movement.

Methods

We examined species richness, abundance, and movement across edges between remnant woodlands and four farmland uses (plantings, fallow, annual crops, woody debris applied over crops post-harvest) in southeastern Australia. We used directional pitfall traps to infer movement, and sampled at edges, and 20 and 200 m on both sides of edges, during spring and summer.

Results

Detritivore and predator abundance varied between seasons across the edge between woodlands and all farmlands, but seasonal differences were weaker for fallow-woodland and woody debris-woodland edges. Detritivores moved from farmlands towards woodlands, but not across fallow-woodlands and woody debris-woodlands edges during summer. During summer, predators showed short-range movement towards edges from all farmlands except plantings, and towards woody debris from woodlands. Edges showed temporally stable predator richness and higher herbivore richness than adjoining habitats.

Conclusions

Farmland use and season interactively affect beetle abundance across farmland-woodland edges. Woody debris can reduce seasonal fluctuations in beetle edge responses and increase permeability for cross-habitat movement, while plantings provide habitat during summer. Edges provide important resources for beetles in adjoining habitats, however, seasonal movement of predators specifically into edges may affect prey assemblages—a link requiring further study.

     

PET AND CAPTIVE BIRDS AS POTENTIAL RESERVOIRS OF ZOONOTIC BACTERIA

Thermophilic Campylobacter spp. and Salmonella spp. are zoonotic bacteria, commonly harbored in the enteric tract of avian species. This survey aimed at verifying the presence of these microorganisms in a heterogeneous Italian population of pet birds and captive birds of prey (e.g., Passeriformes, Psittaciformes, Accipitriformes, Falconiformes, and Strigiformes) that live in close contact with humans. A total of 151 individuals were tested for thermophilic Campylobacter spp. and 444 for Salmonella spp. Six C. jejuni and one S. Livingstone were isolated from birds of prey: 4 Accipitriformes (2 Buteo regalis, 2 Parabuteo unicinctus), 1 Falconiformes (Falco peregrinus) and 1 Strigiformes (Strix aluco) were positive for C. jejuni, and 1 Falconiformes (Falco peregrinus) for S. Livingstone. Five C. jejuni strains were genotyped by Multilocus Sequence Typing (MLST) and identified as ST 2116, assigned to ST-353 CC. Results of this study suggest that these microorganisms are not common inhabitants of the digestive tract of pet birds and captive birds of prey, but occasional findings. However, as potential reservoirs of zoonotic bacteria, pet birds should be monitored in order to preserve human health.     

Fate of a water-soluble herbicide spray on foliage. Part Ii. Absorption and dissipation of foliar msma deposits: Mathematical modelling

MSMA (monosodium methylarsonate) was applied to rice (Oryza sativa L. cv. ‘Labelle’) plants at weekly intervals from the time the plants were 46 cm high until heading. Each application was to a different set of plants. The sprayed plant tops were analysed for MSMA immediately after spraying and at weekly intervals thereafter until heading. MSMA deposits became completely absorbed after one week and then the total residues declined exponentially to background levels with a half-life of about 15 days. Plant stunting effects depended on the amount of MSMA applied and the rate of growth at the time of application. Sterilisation effects depended on the amount of MSMA applied and the proximity in time of the application to panicle initiation. A mathematical model of the data showed that sterility symptoms were consistent with calculated MSMA concentration in tissue at the time of panicle initiation.     

Effect of seed treatment in preventing transmission of dwarf bunt of winter wheat to new areas

The effectiveness of various fungicide formulations containing carboxin and thiabendazole in eradicating teliospores of Tilletia controversa (dwarf bunt) from winter wheat seed was evaluated in the laboratory and the field. In the laboratory tests, the viability of teliospores washed from treated infested seed was greatly reduced as compared to the viability of teliospores washed from untreated infested seed, suggesting that carboxin and thiabendazole were primarily fungicidal. Field tests in two different years were established to determine if teliospores from treated infested seed could infect nearby untreated noninfested seed. Formulations containing carboxin were highly effective in reducing infection of healthy seed. No dwarf bunt infected plants developed in either year from seed treated with ‘Vitaflo 250’. Furthermore, seedborne common bunt caused by Tilletia foetida was nearly eradicated by carboxin-containing formulations in one field test. Carboxin treatment of winter wheat seed infested with dwarf bunt teliospores will greatly reduce the danger of introducing this pathogen into new areas.     

A bacterium against the tiger: further evidence of the potential of noninundative releases of males with manipulated Wolbachia infection in reducing fertility of Aedes albopictus field populations in Italy

BACKGROUND

Incompatible insect technique (IIT) is a population suppression approach based on the release of males with manipulated Wolbachia infection inducing egg inviability in wild females. We here present results of multiple field releases of incompatible ARwP males carried out in 2019 in a 2.7-ha green area within urban Rome (Italy) to assess the effect on Aedes albopictus egg viability. Data are compared with results obtained in 2018, when the approach was tested for the first time in Europe.

RESULTS

An average of 4674 ARwP males were released weekly for 7 weeks, resulting in a mean ARwP:wild male ratio of 1.1:1 (versus 0.7:1 in 2018). Egg-viability dynamics in ovitraps significantly varied between treated and control sites, with an estimated overall reduction of 35% (versus 15% in 2018). The estimated proportion of females classified as mated with ARwP males was 41.8% and the viability rate of eggs laid by these females (9.5%) was on average significantly lower than that of females only mated with wild males (87.8%); however, high variability in fertility was observed. Values of ARwP male competitiveness were 0.36 and 0.73 based on the overall viability rate of eggs in ovitraps and on female fertility, respectively; thus, well above the conventional 0.2 threshold for an effective suppressive impact in the field.

CONCLUSIONS

Results further support the potential of IIT as a tool to contribute to Ae. albopictus control in the urban context, stressing the need for larger field trials to evaluate the cost-efficacy of the approach in temperate regions. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Improving Genetic Engineering Secondary Education Through a Classroom-Ready Online Resource

Genetic engineering has long been used in food production in the United States. However, consumers' science literacy in genetic engineering is poor. Teacher knowledge, time, and resources are lacking in science curriculums on genetic engineering. Through interviews conducted with six high school agriculture teachers we show how a new online resource, The Journey of a Gene, addresses these barriers to help improve their knowledge and increase time spent on genetic engineering. The positive outcomes support funding for genetic engineering education. Education is key to help consumers make informed purchasing decisions and societal decisions about advancing genetic engineering research.     

A new phoretic association: Bursaphelenchus minutus (Nematoda: Parasitaphelenchidae) and Orthotomicus erosus (Coleoptera: Scolitydae) recorded on Pinus pinea (L.)

A new phoretic association between Bursaphelenchus minutus and the bark beetle Orthotomicus erosus collected on Pinus pinea is described for the first time. Nematode identification was based on morphological observation and biometric measurements of males and females. Moreover, B. minutus was characterized by ITS sequences and RFLP profile.     

The Allometric Quarter-Power Scaling Model and Its Applicability to Grand Fir and <Emphasis Type="Italic">Eucalyptus</Emphasis> Trees

The use of the allometric model \(y = \beta x ^{\alpha }\) to describe the relative growth of morphological traits of trees is a source of contention in ecology. This is particularly so in a specific form, the West, Brown and Enquist model, which predicts values of \(\alpha \) that are multiples of 1/4 for various allometric relationships—the quarter-power scaling law. We use statistical techniques to test the appropriateness of the quarter-power scaling allometric model in a number of different relative growth relationships of trees. Two separate datasets are used, one of repeated measures of Abies grandis (Grand fir) trees, another of independent measures of Eucalyptus trees. Nonlinear mixed-effects modelling is used to fit allometric models to the datasets. Generalised additive models, equivalence testing and traditional significance testing are used to assess the adequacy of the allometric models fitted and the values of the estimated exponents relative to those predicted by the WBE model. In only one of the five models fitted was there empirical evidence for the WBE-predicted quarter-power exponent. However, the adequacy of the allometric models was generally supported, though a need for further analysis over a larger range of tree ages/sizes is indicated.Supplementary materials accompanying this paper appear online.