Alterations in Life-History Associated With Non-target-site Herbicide Resistance in Alopecurus myosuroides.

The evolution of resistance to herbicides is a classic example of rapid contemporary adaptation in the face of a novel environmental stress. Evolutionary theory predicts that selection for resistance will be accompanied by fitness trade-offs in environments where the stress is absent. Alopecurus myosuroides, an autumn-germinating grass weed of cereal crops in North-West Europe, has evolved resistance to seven herbicide modes-of-action, making this an ideal species to examine the presence and magnitudes of such fitness costs. Here, we use two contrasting A. myosuroides phenotypes derived from a common genetic background, one with enhanced metabolism resistance to a commercial formulation of the sulfonylurea (ALS) actives mesosulfuron and iodosulfuron, and the other with susceptibility to these actives (S). Comparisons of plant establishment, growth, and reproductive potential were made under conditions of intraspecific competition, interspecific competition with wheat, and over a gradient of nitrogen deprivation. Herbicide dose response assays confirmed that the two lines had contrasting resistance phenotypes, with a 20-fold difference in resistance between them. Pleiotropic effects of resistance were observed during plant development, with R plants having a greater intraspecific competitive effect and longer tiller lengths than S plants during vegetative growth, but with S plants allocating proportionally more biomass to reproductive tissues during flowering. Direct evidence of a reproductive cost of resistance was evident in the nitrogen deprivation experiment with R plants producing 27% fewer seed heads per plant, and a corresponding 23% reduction in total seed head length. However, these direct effects of resistance on fecundity were not consistent across experiments. Our results demonstrate that a resistance phenotype based on enhanced herbicide metabolism has pleiotropic impacts on plant growth, development and resource partitioning but does not support the hypothesis that resistance is associated with a consistent reproductive fitness cost in this species. Given the continued difficulties associated with unequivocally detecting costs of herbicide resistance, we advocate future studies that adopt classical evolutionary quantitative genetics approaches to determine genetic correlations between resistance and fitness-related plant life history traits.

The relative benefits of green versus lean office space: three field experiments.

Principles of lean office management increasingly call for space to be stripped of extraneous decorations so that it can flexibly accommodate changing numbers of people and different office functions within the same area. Yet this practice is at odds with evidence that office workers' quality of life can be enriched by office landscaping that involves the use of plants that have no formal work-related function. To examine the impact of these competing approaches, 3 field experiments were conducted in large commercial offices in The Netherlands and the U.K. These examined the impact of lean and "green" offices on subjective perceptions of air quality, concentration, and workplace satisfaction as well as objective measures of productivity. Two studies were longitudinal, examining effects of interventions over subsequent weeks and months. In all 3 experiments enhanced outcomes were observed when offices were enriched by plants. Implications for theory and practice are discussed.

We can work it out: Group decision-making builds social identity and enhances the cognitive performance of care residents.

Group-based interventions have been argued to slow the cognitive decline of older people residing in care by building social identification and thereby increasing motivation and engagement. The present study explored the identity-cognition association further by investigating the impact of a group decision-making intervention on cognition. Thirty-six care home residents were assigned to one of three conditions: an Intervention in which they made decisions about lounge refurbishment as a group, a Comparison condition in which staff made these decisions, or a no-treatment Control. Cognitive function, social identification, home satisfaction, and lounge use were measured before and after the intervention. Participants in the Intervention condition showed significant increases on all measures, and greater improvement than participants in both Comparison and Control conditions. Consistent with social identity theorizing, these findings point to the role of group activity and social identification in promoting cognitive integrity and well-being among care residents.

The relative merits of lean, enriched, and empowered offices: an experimental examination of the impact of workspace management strategies on well-being and productivity.

Principles of lean management encourage managers to exert tight control over office space and the people within it. Alternative, design-led approaches promote the value of offices that are enriched, particularly by plants and art. On the basis of a social identity perspective, we argue that both of these approaches may compromise organizational outcomes by disempowering workers and failing to give them input into the design of their office space. This hypothesis is tested in two experiments (ns = 112, 47). The first was conducted in an interior office in a psychology department, the second in a commercial city office. In 4 independent conditions we examine the impact of space management strategies in which the office is either (a) lean, (b) decorated by the experimenter (with plants and art), (c) self-decorated, or (d) self-decorated and then redecorated by the experimenter. We examine the impact of these conditions on organizational identification, well-being, and various forms of productivity (attention to detail, information processing, information management, and organizational citizenship). In both experiments, superior outcomes are observed when offices are decorated rather than lean. However, further improvements in well-being and productivity are observed when workers have input into office decoration. Moreover, these effects are attenuated if this input is overridden. Implications for theory and practice are discussed. In particular, findings point to the need to question assumptions about the merits of lean office space management that have been dominant throughout the last century.