Medium-term seed storage of 50 genera of forage legumes and evidence-based genebank monitoring intervals

Genebanks maintaining seeds for long-term genetic resources conservation monitor seed lots to detect early loss in viability. Monitoring is costly and depletes valuable seed. Three decades of genebank seed germination test results of diverse forage species from 50 legume genera in the International Livestock Research Institute’s medium-term store (circa 8° C with 5 % moisture content) were analysed to determine whether advice on seed monitoring intervals could be derived. Cumulative normal distributions were fitted by probit analysis for each seed lot and compared within each genus. Six patterns of within-genus variation were identified: no detectable trend in germination test results during storage (4 genera); detectable trends, but variable (positive to negative) amongst lots (5); consistent slope of loss in viability amongst lots (17); consistent slope of increase in ability to germinate amongst lots (21); common loss in viability amongst lots (2); common increase in ability to germinate amongst lots (1). Seed lot monitoring intervals for the medium-term store were derived for each of 19 genera with consistent loss in viability across seed lots: three genera provided comparatively rapid deterioration, five met the general expectations for a medium-term store (2-10 years’ maintenance of high viability), whilst 11 provided much better survival. Moreover, 26 further genera provided no evidence as yet of seed deterioration; of these, 22 improved in ability to germinate during storage indicating confounding of hardseededness with viability in germination tests

Ectomycorrhizal fungal communities of native and non-native Pinus and Quercus species in a common garden of 35-year-old trees

Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan and novel fungi

Renal HIV Expression Is Unaffected by Serum LPS Levels in an HIV Transgenic Mouse Model of LPS Induced Kidney Injury

Acute kidney injury (AKI) is associated with increased rates of mortality. For unknown reasons, HIV infected individuals have a higher risk of AKI than uninfected persons. We tested our hypothesis that increased circulating LPS increases renal expression of HIV and that HIV transgenic (Tg26) mice have increased susceptibility to AKI. Tg26 mice harbor an HIV transgene encoding all HIV genes except gag and pol, and develop a phenotype analogous to HIVAN. Mice were used at 4–6 weeks of age before the onset of gross renal disease. Mice were injected i.p. with LPS or sterile saline. Renal function, tubular injury, cytokine expression, and HIV transcription were evaluated in Tg26 and wild type (WT) mice. LPS injection induced a median 60.1-fold increase in HIV expression in spleen but no change in kidney. There was no significant difference in renal function, cytokine expression, or tubular injury scores at baseline or 24 hours after LPS injection. HIV transcription was also analyzed in vitro using a human renal tubular epithelial cell (RTEC) line. HIV transcription increased minimally in human RTEC, by 1.47 fold, 48 hours after LPS exposure. We conclude that Tg26 mice do not increase HIV expression or have increased susceptibility to LPS induced AKI. The increased risk of AKI in HIV infected patients is not mediated via increased renal expression of HIV in the setting of sepsis. Moreover, renal regulation of HIV transcription is different to that in the spleen

Sustainable drainage system site assessment method using urban ecosystem services

The United Kingdom's recently updated approach to sustainable drainage enhanced biodiversity and amenity objectives by incorporating the ecosystem approach and the ecosystem services concept. However, cost-effective and reliable methods to appraise the biodiversity and amenity values of potential sustainable drainage system (SuDS)sites and their surrounding areas are still lacking, as is a method to enable designers to distinguish and link the amenity and biodiversity benefits that SuDS schemes can offer. In this paper, therefore, the authors propose two ecosystem services- and disservices-based methods (i.e. vegetation structure cover-abundance examination and cultural ecosystem services and disservices variables appraisal) to aid SuDS designers to distinguish and link amenity and biodiversity benefits, and allow initial site assessments to be performed in a cost-effective and reliable fashion. Forty-nine representative sites within Greater Manchester were selected to test the two methods. Amenity and biodiversity were successfully assessed and habitat for species, carbon sequestration, recreation and education ecosystem services scores were produced,which will support SuDS retrofit design decision-making. Large vegetated SuDS sites with permanent aquatic features were found to be most capable of enhancing biodiversity- and amenity-related ecosystem services. Habitat for species and recreation ecosystem services were also found to be positively linked to each other. Finally, waste bins on site were found to help reduce dog faeces and litter coverage. Overall, the findings presented here enable future SuDS retrofit designs to be more wildlife friendly and socially inclusive

Ecological correlates of seed dormancy differ among dormancy types: A case study in the legumes

Comment on Rubio de Casas et al. (2017) ‘Global biogeography of seed dormancy is determined by seasonality and seed size: a case study in legumes’. Seed dormancy, and seed dormancy classes. Seed germination and seedling survival are crucial in determining species distributions, and plant population and community dynamics (Larson & Funk, 2016). By controlling the timing of germination, seed dormancy plays an important role in seedling survival, particularly in seasonal environments (Willis et al., 2014). The recent paper by Rubio de Casas et al. (2017) examined the seed size and global distributions of dormant compared with nondormant (ND) members of the Fabaceae, finding that dormant seeds are typically smaller than ND seeds, and are clearly associated with, and evidently have adaptive value in, more seasonal environments. This paper has made a valuable contribution to our understanding of the ecology and evolution of seed dormancy within the Fabaceae. However, the term ‘seed dormancy’ (defined at its simplest as a ‘block to the completion of germination of an intact viable seed under favourable conditions’ (p. 502); Finch‐Savage & Leubner‐Metzger, 2006) encompasses a diverse range of different physiological and structural mechanisms, which can be broadly split into discrete dormancy ‘classes’ (e.g. Baskin & Baskin, 2014) and can differ in prevalence among habitats, climatic zones, and taxonomic lineages (Finch‐Savage & Leubner‐Metzger, 2006). Within the Fabaceae, species with ‘dormant’ seeds can be assigned one of three dormancy classes: physiological dormancy (PD; where dormancy is broken in response to particular environmental cues such as warm or cold temperature), physical dormancy (PY; where the seed coat is impermeable to water thereby preventing imbibition; i.e. ‘hard seededness’), and combinational dormancy (PYPD; where a seed has both physical and physiological dormancy) (Baskin & Baskin, 2014). PY is the dominant dormancy class within the Fabaceae, with PD and PYPD making up a small minority of species

Taxonomic affinity, habitat and seed mass strongly predict seed desiccation response: A boosted regression trees analysis based on 17 539 species

Background and Aims: Seed desiccation response plays an important role in plant regeneration ecology, and has significant implications for species conservation. The majority of seed plants produce desiccation-tolerant (orthodox) seeds, whilst comparatively few produce desiccation-sensitive (recalcitrant) seeds that are unable to survive dehydration, and which cannot be conserved in traditional seed banks. This study develops a set of models to predict seed desiccation response in unstudied species. Methods: Taxonomy, trait, location and climate data were compiled to form a global data set of 17 539 species. Three boosted regression trees models were then developed to predict species' seed desiccation responses based on habitat and trait information for the species, and the seed desiccation responses of close relatives (either members of the same genus, family or order, depending on the model). Ten-fold cross-validation was used to test model predictive success. The utility of the models was then demonstrated by predicting seed desiccation response for two floras: Ecuador, and Britain and Ireland. Key Results: The three models had varying success rates for identifying the desiccation-sensitive species: 89 % for the genus-level model, 79 % for the family-level model and 60 % for the order-level model. The most important predictor variables were the seed desiccation responses of a species' relatives, seed mass and annual precipitation. It is predicted that 10 % of seed plants from Ecuador and 1.2 % of those from Britain and Ireland produce desiccation-sensitive seeds. Due to data availability, prediction accuracy is likely to be higher for the British and Irish flora, where it is estimated that a desiccation-sensitive species had a 96.7 % chance of being correctly identified, compared with 80.8 % in the Ecuador flora. Conclusions: These models can utilize existing data to predict species' likely seed desiccation responses, providing a gap-filling tool for global studies of plant traits, as well as critical decision-making support for plant conservation activities