Mating disruption method against the vine mealybug,Planococcus ficus: effect of sequential treatment on infested vines

The vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), is a major pest of vineyards. Here, we tested the efficacy of the mating disruption method against the pest when applied during one or two successive years in high and low infestation levels. Following 1 year of treatment, at low initial infestation levels a shutdown of pheromone traps was observed, along with a significant reduction in infested vines. With initially high infestation levels, a gradual reduction in infested vines was observed, with a trap shutdown seen only after the second year of pheromone application. We discuss the implications of the male mating disruption method for this pest in which the wingless females are aggregated with limited movement among vines, offering multiple mating opportunities for the flying male.     

The biosynthesis of Dufour's gland constituents in queens of the honeybee (Apis mellifera)

Chemical analysis of queen Dufour's gland by GC/MS revealed the presence of long chain esters and hydrocarbons. To evaluate whether the biosynthesis of Dufour's gland components is modulated by physiological factors, we studied thede novo biosynthesis of esters and hydrocarbons in virgin and mated queen glandsin vivo andin vitro. Using [1-¹⁴C] sodium acetate as a precursor, it was shown thatin vivo, esters and hydrocarbons comprised the majorde novo products. The relative proportion of the hydrocarbon fraction was significantly higher in mated queens than in virgins, while in esters the situation was reversed. Comparision between reproductive and non reproductive virgin queens revealed that mating and not egg laying induced changes in glandular activity. Glands incubatedin vitro, on the other hand, synthesized mainly esters and alcohols but not hydrocarbons. These results suggest that either hydrocarbons are produced elsewhere and subsequently sequestered by Dufour's gland, or that the gland biosynthetic expressionin vivo is modulated. Differences between the gland activityin vivo andin vitro further support the hypothesis of a physiological mechanism in regulation of glandular performance.     

Effect of Metal-Rich Sewage Sludge Application on the Bacterial Communities of Grasslands

The effect of long-term application of heavy metal-laden sewage sludge on the total heterotrophic aerobic and the cadmium-resistant soil bacterial communities was studied. Gram-positive bacteria were completely absent from resistant communities. These findings suggest that this group is highly susceptible to Cd. Shannon's diversity indices estimated for total communities did not reveal negative effects on the communities that developed in the presence of sludge. However, Cd-resistant communities isolated from long-term sludge-amended soils were more diverse than the resistant communities from a control sample, suggesting that adaptation to Cd as a stressor had occurred in the presence of sludge constituents. This higher diversity was attributed to Cd resistance in pseudomonads and gram-negative fermenters. Resistance did not develop by dissemination of Cd resistance plasmids, because these were rarely detected in the genomes of resistant strains.     

Who is Responsible for Fission in a Free-ranging Troop of Baboons?

The study troop of chacma baboons (Papio cynocephalus ursinus) at Mkuzi Game Reserve, Zululand, South-Africa, comprised of about 76 members that split into two new troops. The events leading to this troop fission will be described and its possible causes will be discussed. Troop fission among baboons is generally attributed to the withdrawal of low-ranking females from the main group, as a result of the cost of food competition and its effect on their reproductive success. At Mkuzi, no evidence for food competition among females was recorded in terms of rank-related time spent feeding or other time—budget components, feeding-bout length, diet composition or context of female aggression. Moreover, no evidence for rank-related differential reproductive success was found in terms of inter-birth intervals or infant survival. Female mortality was, however, related to dominance rank, with circumstantial evidence suggesting that cause of mortality was predation by leopards. Rate of female disappearances, aggression levels among females, and the percentage of time they spent in proximity to other adult troop members increased after fission. Relatively short inter-birth intervals and extremely low infant mortality rate at Mkuzi resulted in a small number of receptive females at any one time, and therefore in high costs of male sexual competition as expressed in the high levels of male aggression and woundings, both reduced after fission. It is suggested that this troop fission may have been initiated by the resident males, triggered by the high cost of sexual competition, and forced on the females, who were, consequently, subjected to higher risk of predation. The troop fission was preceded by a long process of increasing tendency for sub-trooping. It was initiated by the four resident males who kept a large distance apart from each other, herded oestrous female associates away from others and were followed by other females. The females generally tended to stay close to associates, males and females. These parties were followed by the peripheral and immigrant males who had no female associates, and eventually two distinct daughter troops were formed.     

Interactive Visualization and Industrial Ecology: Applications,Challenges, and Opportunities

The emergence of increasingly complex data in industrial ecology (IE) has caused scholarly interest in interactive visualization (IV). IV allows users to interact with data, aiding in processing and interpreting complex datasets, processes, and simulations. Consequently, IV can help IE practitioners communicate the complexities of their methods and results, shed light on the underlying research assumptions, and enable more transparent monitoring of data quality and error. This can significantly increase the reach and impact of research, promote transparency, reproducibility, and open science, as well as improve the clarity and presentation of IE research. A review of current IV applications reveals that, while data exploration has received some attention among IE practitioners, IV applications in scientific communication are clearly lacking. With the help of a working example, we explore the value of IV, discuss its operationalization, and highlight challenges that the IE community must face during IV uptake. Such challenges include technical and knowledge limitations, limits on user interaction, and implementation strategies. With these challenges in mind, we outline key aspects needed to lift the IE field to the forefront of scientific communication in the coming years. Among these, we draft the basic principles of a “Hub for Interactive Visualization in Industrial Ecology” (HIVE), a point of encounter where IE practitioners could find an array of data visualization tools that are geared toward IE datasets. IV is here to stay, and its inceptive stage presents many opportunities to IE practitioners to shape its operationalization and benefit from early adoption.     

Sharing economy rebound: The case of peer-to-peer sharing of food waste

The digital sharing economy is commonly thought to promote sustainable consumption and improve material efficiency through better utilization of existing product stocks. However, the cost savings and convenience of using digital sharing platforms can ultimately stimulate additional demand for products and services. As a result, some or even all of the expected environmental benefits attributed to sharing could be offset, a phenomenon known as the rebound effect. Relying on a unique dataset covering over 750,000 food items shared in the United Kingdom through a free peer-to-peer food-sharing platform, we use econometric modeling, geo-spatial network analysis, and environmentally extended input–output analysis to quantify how much of the expected environmental benefits attributed to sharing are offset via rebound effects under seven re-spending scenarios. We find that rebound effects can offset 59–94% of expected greenhouse gas (GHG) emission reduction, 20–81% of expected water depletion benefits, and 23–90% of land use benefit as platform users re-spent the money saved from food sharing on other goods and services. Our results demonstrate that rebound effects could limit the potential to achieve meaningful reductions in environmental burdens through sharing, and highlight the importance of incorporating rebound effects in environmental assessments of the digital sharing economy.     

Non-indigenous insect species in Israel and adjacent areas

Non-indigenous species cause great damage worldwide. Non-indigenous insects are known as harmful in many regions, but few comprehensive works have investigated non-indigenous insects as a group. We compiled a comprehensive database of established non-indigenous (ENI) insects in Israel and adjacent regions to investigate how they arrived, their biological characteristics, and the attributes of areas they invade. Of 218 species of ENI insects in this region, 124 are widespread. Most species came as stowaways, but 38 were brought intentionally for biological control. Most ENI insects in this region are in the Coleoptera, Diptera, Hymenoptera, Lepidoptera, and Homoptera. Species from various orders differ in their tendency to be localized or widespread, and in biogeographic origins. The distribution of species among orders differs between native and ENI insects. The Coastal Plain houses the most ENI insect species and the Negev and Judean deserts the fewest. Most ENI insects spread from the Coastal Plain to other regions. Absence of roads, settlements and presence of nature reserves are negatively correlated with occurrence of ENI species. Seventy-nine species are categorized as pests that damage produce, merchandise, forestry, etc. Despite a general dearth of knowledge on impacts of ENI insects on natural systems, 42 species are known to feed on native plants, some of conservation concern. Biological control agents are usually more limited in their distribution than other ENI insects. Further research, legislation, and enforcement are required to minimize effects of these species on agriculture and natural habitats.     

Neocentromeres Form Efficiently at Multiple Possible Loci in Candida albicans

Centromeres are critically important for chromosome stability and integrity. Most eukaryotes have regional centromeres that include long tracts of repetitive DNA packaged into pericentric heterochromatin. Neocentromeres, new sites of functional kinetochore assembly, can form at ectopic loci because no DNA sequence is strictly required for assembly of a functional kinetochore. In humans, neocentromeres often arise in cells with gross chromosome rearrangements that rescue an acentric chromosome. Here, we studied the properties of centromeres in Candida albicans, the most prevalent fungal pathogen of humans, which has small regional centromeres that lack pericentric heterochromatin. We functionally delimited centromere DNA on Chromosome 5 (CEN5) and then replaced the entire region with the counter-selectable URA3 gene or other marker genes. All of the resulting cen5Δ::URA3 transformants stably retained both copies of Chr5, indicating that a functional neocentromere had assembled efficiently on the homolog lacking CEN5 DNA. Strains selected to maintain only the cen5Δ::URA3 homolog and no wild-type Chr5 homolog also grew well, indicating that neocentromere function is independent of the presence of any wild-type CEN5 DNA. Two classes of neocentromere (neoCEN) strains were distinguishable: “proximal neoCEN” and “distal neoCEN” strains. Neocentromeres in the distal neoCEN strains formed at loci about 200–450 kb from cen5Δ::URA3 on either chromosome arm, as detected by massively parallel sequencing of DNA isolated by CENP-A^Cse4p chromatin immunoprecipitation (ChIP). In the proximal neoCEN strains, the neocentromeres formed directly adjacent to cen5Δ::URA3 and moved onto the URA3 DNA, resulting in silencing of its expression. Functional neocentromeres form efficiently at several possible loci that share properties of low gene density and flanking repeated DNA sequences. Subsequently, neocentromeres can move locally, which can be detected by silencing of an adjacent URA3 gene, or can relocate to entirely different regions of the chromosome. The ability to select for neocentromere formation and movement in C. albicans permits mechanistic analysis of the assembly and maintenance of a regional centromere.