Research Summary• The relationship between cool-season grasses and fungal endophytes is widely regarded as mutualistic, but there is growing uncertainty about whether changes in resource supply and environment benefit both organisms to a similar extent.• Here, we infected two perennial ryegrass ( Lolium perenne ) cultivars (AberDove, Fennema) that differ in carbohydrate content with three strains of Neotyphodium lolii (AR1, AR37, common strain) that differ intrinsically in alkaloid profile. We grew endophyte-free and infected plants under high and low nitrogen (N) supply and used quantitative PCR (qPCR) to estimate endophyte concentrations in harvested leaf tissues.• Endophyte concentration was reduced by 40% under high N supply, and by 50% in the higher sugar cultivar. These two effects were additive (together resulting in 75% reduction). Alkaloid production was also reduced under both increased N supply and high sugar cultivar, and for three of the four alkaloids quantified, concentrations were linearly related to endophyte concentration.• The results stress the need for wider quantification of fungal endophytes in the grassland-foliar endophyte context, and have implications for how introducing new cultivars, novel endophytes or increasing N inputs affect the role of endophytes in grassland ecosystems.

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Animal Ecology. Summary 1. The preference of sheep for two temperate grassland species, ryegrass and white clover, was tested by releasing flocks (of three ewes) onto swards (0-25 ha) that contained adjacent monocultures of grass and clover, and observing their intake behaviour over 6 days. The test paddocks contained either 20, 50, or 80% clover by ground area to distinguish partial preference from indifference. 2. To test whether recent diet affected preference, separate groups of dry (nonpregnant, non-lactating) ewes grazed prior to testing on one of three diet 'backgrounds': an all-grass sward, an all-clover sward, or a 50:50 grass/clover sward by area. To consider the effects of physiological state on preference, a further group of lactating ewes, also from a 50:50 grass/clover 'background', were tested. 3. In all cases, the mean diet obtained was a mixture of grass and clover, even though greater intake rates would have been obtained eating pure clover. There was a consistent temporal pattern to preference, with ewes showing the greatest preference for clover in the morning. The results suggest that previous diet 'background' can have lasting effects on preference. Ewes that had been recently grazing monocultures initially showed an increased preference for the opposite species to the one they had been grazing. Over 6 days these animals gradually reverted to a preference for their 'background' diet. 4. Despite major differences in the energy requirement and intake behaviour of dry vs. lactating ewes, no significant effects of physiological state on preference were detected. Sheep grazing from swards of 20% clover spent a smaller proportion of time grazing clover and had a smaller proportion of clover in their diet than those grazing from 50% or 80% clover swards though, in all cases, behaviour was consistent with a preference for a high proportion of clover: sheep were not grazing at random. 5. Overall, the results demonstrate that sheep sustain a mixed diet even in situations where a monospecific diet is readily possible. Several alternative hypotheses to explain this (partial preference, novelty, rarity, 'sampling') are discussed. We suggest the results provide evidence of partial and changing preference by sheep. Our results urge caution in infering long-term grazing behaviour from short-term tests of preference and suggest why knowledge of diet preference even in common herbivores remains equivocal. Journal of Animal Ecology (1994) 63, 465-478 Diet preference of sheepanimal grazing unselectively could take its entire daily intake of dry matter from a few square m...

Purpose -The purpose of this paper is to show how macro-social marketing and social engineering can be integrated and to illustrate their use by governments as part of a positive social engineering intervention with examples from the Canadian anti-smoking campaign. Design/methodology/approach -This is a conceptual paper that uses the case of the Canadian anti-smoking campaign to show that macro-social marketing, as part of a wider systems approach, is a positive social engineering intervention. Findings -The use of macro-social marketing by governments is most effective when it is coupled with other interventions such as regulations, legislation, taxation, community mobilization, research, funding and education. When a government takes a systems approach to societal change, such as with the Canadian anti-smoking campaign, this is positive use of social engineering.Research limitations/implications -The social marketer can understand their role within the system and appreciate that they are potentially part of precipitating circumstances that make society susceptible to change. Social marketers further have a role in creating societal motivation to change, as well as promoting social flexibility, creating desirable images of change, attitudinal change and developing individual's skills, which contribute to macro-level change. Practical implications -Social marketers need to understand the structural and environmental factors contributing to the problem behavior and focus on the implementers and controllers of society-wide strategic interventions. Social implications -Eliminating all factors which enable problem behaviors creates an environmental context where it is easy for consumers to change behavior and maintain that change. Originality/value -The value of this paper is in extending the literature on macro-social marketing by governments and identifying the broader strategy they may be undertaking using positive social engineering. It is also in showing how marketers may use this information.

Purpose -The purpose of this paper is to examine the role of atmospherics in the creation of an hedonic retail experience by comparing the perceived differences between a retail environment attempting to provide an hedonic experience and one with a more utilitarian focus. Design/methodology/approach -A qualitative methodology was employed, using protocol analysis and in-depth semi-structured interviews that were conducted with ten participants. Findings -The paper highlights several atmospheric cues and their influence on the hedonic retail experience. The first category of cues -attractive stimuli -were those cues that attracted attention, exciting the participant and eliciting approach behaviours. The second category -facilitating stimuliincluded those cues that were necessary in order to facilitate product engagement. Originality/value -The paper provides a broad categorisation of atmospheric cues, providing factors that shop designers can be aware of when creating a store with the hedonic experience in mind.

A previously described model of grass growth was used to analyse the effect of the severity of defoliation and the duration of the subsequent regrowth on the overall balance between photosynthesis, gross tissue production and leaf death and so on the amount that could be harvested/consumed per hectare under intermittent defoliation. Maximum yield per hectare was shown to be achieved whenever the fluctuations in LAI during regrowth and defoliation led lo the same low average LAI that was previously shown to give maximum yield (amount harvested/consumed per hectare) under continuous grazing. Thus, it is suggested that production under both continuous and intermittent defoliation may best be characterized, and diverse managements may be rationalized, on the basis of the average sward state, the average achieved. The analysis leads us to reconsider some widely held concepts of the growth and utilization of grass applied in both agronomic and ecological theory, and the provision of practical guidelines for management.

Lolium perenne cultivars differing in their capacity to accumulate water soluble carbohydrates (WSCs) were infected with three strains of fungal Neotyphodium lolii endophytes or left uninfected. The endophyte strains differed in their alkaloid profiles. Plants were grown at two different levels of nitrogen (N) supply in a controlled environment. Metabolic profiles of blades were analyzed using a variety of analytical methods. A total of 66 response variables were subjected to a principle components analysis and factor rotation. The first three rotated factors (46% of the total variance) were subsequently analyzed by analysis of variance. At high N supply nitrogenous compounds, organic acids and lipids were increased; WSCs, chlorogenic acid (CGA), and fibers were decreased. The high-sugar cultivar 'AberDove' had reduced levels of nitrate, most minor amino acids, sulfur, and fibers compared to the control cultivar 'Fennema', whereas WSCs, CGA, and methionine were increased. In plants infected with endophytes, nitrate, several amino acids, and, magnesium were decreased; WSCs, lipids, some organic acids, and CGA were increased. Regrowth of blades was stimulated at high N, and there was a significant endophyte 3 cultivar interaction on regrowth. Mannitol, a fungal specific sugar alcohol, was significantly correlated with fungal biomass. Our findings suggest that effects of endophytes on metabolic profiles of L. perenne can be considerable, depending on host plant characteristics and nutrient supply, and we propose that a shift in carbon/N ratios and in secondary metabolite production as seen in our study is likely to have impacts on herbivore responses.

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Pastoral-based animal production systems are under increasing pressure to provide the high quantity and quality of feed needed for optimal ruminant performance. The capacity of farmers to increase forage yield further, solely by increasing fertilizer inputs or through improved pasture management, is limited. Emerging requirements to balance industry production targets against the need to reduce greenhouse gas emissions and N losses pose further challenges. Plant breeding is being asked to deliver results more urgently than at any time previously, and this review attempts to highlight issues that might limit the prospects for future progress by seeking lessons from four past examples: (i) white clover breeding gains and the need to consider the complexity of the grazed grass-clover mixed sward, with its tendency for cycling in plant species composition; (ii) a systems field trial of new and old grass ⁄ clover cultivars, and how the complexity of growth of perennial forage crops, and the dynamic optimality required for sustainable harvesting might limit our ability to breed for 'yield' per se; (iii) the manipulation of a physiological trait (low 'maintenance' respiration) and the implications of such changes for plant fitness and G · E interactions; and (iv) an hypothesis-driven development of a trait (high-sugar grasses) and the value of 'proof of concept' studies, the requirement of scientific understanding of the mechanisms of trait expression, and how one might in future go about assessing breeding achievements. We discuss the general ecological considerations around shifts in the frequency distribution of traits in new populations, whether altered conventionally or by genetic modification, and how selection for a particular trait might inadvertently reduce both fitness and persistence. A major priority for breeding, we propose, might be to revisit previously abandoned traits that affected the physiological performance of forage species, armed now with a capacity to monitor gene expression at the molecular level, and so unravel ⁄ control the G · E interactions that limited their benefits. We also discuss how a 'loss of yield advantage' of new cultivars, seen when tested several years after sowing, requires urgent investigation and propose this might be associated with fitness costs of perenniality. Finally, we argue for a careful reconsideration of what are realistic expectations for systems field trials and that focus on forage breeding might be shifted more to 'proof of concept' studies, critical experimental design, comparing 'traits' rather than 'cultivars', and the wider ecological assessment of fitness and function of traits in the plant, community and ecosystem.