A global approach to crop wild relative conservation: securing the gene pool for food and agriculture

In light of the growing concern over the potentially devastating impacts on biodiversity and food security of climate change and the massively growing world population, taking action to conserve crop wild relatives (CWR), is no longer an option — it is a priority. Crop wild relatives are species closely related to crops, including their progenitors, many of which have the potential to contribute beneficial traits to crops, such as pest or disease resistance, yield improvement or stability. They are a critical component of plant genetic resources for food and agriculture (PGRFA), have already made major contributions to crop production and are vital for future food security; their systematic conservation in ways that ensure their continuing availability for use is therefore imperative. This is a complex, interdisciplinary, global issue that has been addressed by various national and international initiatives. Drawing on the lessons learnt from these initiatives we can now propose a global approach to CWR conservation, the key elements of which are: (1) estimating global CWR numbers, (2) assessment of the global importance of CWR diversity, (3) current conservation status, (4) threats to CWR diversity, (5) systematic approaches to CWR conservation, (6) CWR informatics, and (7) enhancing the use of CWR diversity.     

Differential physiological and biochemical responses of Quercus infectoria and Q. libani to drought and charcoal disease

The vast oak-dominated forests of the Zagros Mountains in southwestern Iran currently undergo large-scale dieback driven by a combination of drought and increasing incidence of charcoal disease caused by the fungal pathogens Biscogniauxia mediterranea and Obolarina persica. Here, we explore the interactive effects between drought and charcoal disease agents on the physiology and biochemistry of Quercus infectoria and Quercus libani seedlings. The combination of pathogen attack and water limitation hampered plant development, especially in Q. libani seedlings, negatively affecting growth, biomass production, photosynthetic efficiency, and leaf water potential. An increase in markers of oxidative damage together with the upregulation of the antioxidant defense revealed that drought stress and pathogen infection led to pro-oxidative conditions in both oak species, especially in Q. libani, where larger changes in malondialdehyde and hydrogen peroxide occurred. The upregulation of the antioxidant system was more prominent in Q. infectoria than in Q. libani, resulting in enhanced enzyme activity and accumulation of non-enzymatic antioxidants. Fungal infection stimulated the activity of chitinase, phenylalanine ammonia lyase and β-1,3-glucanase in Q. infectoria leaves and this response became more pronounced under water shortage. Our study highlights that drought stress greatly intensifies the effects of the charcoal disease. Moreover, our findings imply superior stress resistance of Q. infectoria conferred by a highly efficient antioxidant system, strong osmotic adjustment (through proline), and increases in resistance enzymes and secondary metabolites (phenols and flavonoids). Future investigations should focus on adult trees in their natural habitat including interactions with soil factors and other pathogens like nematodes, bacteria and other fungi. Because the present research was conducted on oak seedlings, the findings can be considered by forest nursery managers.     

Sampling Time and Performance in Rat Whisker Sensory System

We designed a behavioural paradigm for vibro-tactile detection to characterise the sampling time and performance in the rat whisker sensory system. Rats initiated a trial by nose-poking into an aperture where their whiskers came into contact with two meshes. A continuous nose-poke for a random duration triggered stimulus presentation. Stimuli were a sequence of discrete Gaussian deflections of the mesh that increased in amplitude over time – across 5 conditions, time to maximum amplitude varied from 0.5 to 8 seconds. Rats indicated the detected stimulus by choosing between two reward spouts. Two rats completed more than 500 trials per condition. Rats'' stimulus sampling duration increased and performance dropped with increasing task difficulty. For all conditions the median reaction time was longer for correct trials than incorrect trials. Higher rates of increment in stimulus amplitude resulted in faster rise in performance as a function of stimulus sampling duration. Rats'' behaviour indicated a dynamic stimulus sampling whereby nose-poke was maintained until a stimulus was correctly identified or the rat experienced a false alarm. The perception was then manifested in behaviour after a motor delay. We thus modelled the results with 3 parameters: signal detection, false alarm, and motor delay. The model captured the main features of the data and produced parameter estimates that were biologically plausible and highly similar across the two rats.     

Mathematical Models of Localized Muscle Fatigue: Sensitivity Analysis and Assessment of Two Occupationally-Relevant Models

Muscle fatigue models (MFM) have broad potential application if they can accurately predict muscle capacity and/or endurance time during the execution of diverse tasks. As an initial step toward facilitating improved MFMs, we assessed the sensitivity of selected existing models to their inherent parameters, specifically that model the fatigue and recovery processes, and the accuracy of model predictions. These evaluations were completed for both prolonged and intermittent isometric contractions, and were based on model predictions of endurance times. Based on a recent review of the literature, four MFMs were initially chosen, from which a preliminary assessment led to two of these being considered for more comprehensive evaluation. Both models had a higher sensitivity to their fatigue parameter. Predictions of both models were also more sensitive to the alteration of their parameters in conditions involving lower to moderate levels of effort, though such conditions may be of most practical, contemporary interest or relevance. Although both models yielded accurate predictions of endurance times during prolonged contractions, their predictive ability was inferior for more complex (intermittent) conditions. When optimizing model parameters for different loading conditions, the recovery parameter showed considerably larger variability, which might be related to the inability of these MFMs in simulating the recovery process under different loading conditions. It is argued that such models may benefit in future work from improving their representation of recovery process, particularly how this process differs across loading conditions.     

Predator–prey relationships in a middle Asian Montane steppe: Persian leopard versus urial wild sheep in Northeastern Iran

Management controversies arise when both of the prey and predator in an ecosystem are species of conservation concern. We investigated trophic interactions between the endangered Persian leopard (Panthera pardus saxicolor) and a declining mountain ungulate, urial wild sheep (Ovis vignei), on a high-altitude steppe of Iran. During two consecutive photo-trapping seasons of 1,300 nights in total, a minimum population of four adult leopards (one female and three males) was documented. Scat analysis indicated that urial wild sheep was the staple of the leopard diet with 48.44 % of total biomass consumed. Remains of domestic livestock in leopard scats were negligible yet alarming (14.53 % biomass consumed), followed by wild pigs (8.13 %) and wild goat (1.26 %). Financial costs of leopard depredation to livestock breeders during our study period were comparatively lower than livestock–leopard conflict hotspots across Iran. Using distance sampling, urial density was 15.8 individuals km^?2 (±SE 6.2), and a total biomass of 47,621.5 kg for wild ungulates in the study area was estimated. We estimated that the annual removal rate of urial by leopards during our study period was 9.4 % of the total urial population. We suggest that continuous monitoring of the leopard and prey populations to assess predation impact should be considered, particularly in areas where a single species comprises a remarkable proportion of the leopard diet. In the meantime, assessing probable conflicts with local communities is recommended as a parallel management action to ensure long-term human–leopard coexistence. Our findings will aid wildlife managers in prey-depleted arid environments of western Asia to identify susceptible wild prey populations to predation by large carnivores; hence, significantly contribute in development and implementation of effective conservation measures to mitigate management conflicts.     

APOA2 ?256T>C polymorphism interacts with saturated fatty acids intake to affect anthropometric and hormonal variables in type 2 diabetic patients

Recent studies have established the interaction between APOA2 −256T>C polymorphism and dietary saturated fatty acids intake in relation to obesity on healthy individuals. In the current study, we investigate the effects of this interaction on anthropometric variables and serum levels of leptin and ghrelin in patients with type 2 diabetes. In this cross-sectional study, 737 patients with type 2 diabetes mellitus (290 males and 447 females) were recruited from diabetes clinics in Tehran. The usual dietary intake of all participants during the last year was obtained by validated semiquantitative food frequency questionnaire. APOA2 genotyping was performed by real-time PCR on genomic DNA. No significant relation was obtained by univariate analysis between anthropometric variables and APOA2 genotypes. However, after adjusting for age, gender, physical activity and total energy intake, we identified a significant interaction between APOA2-saturated fatty acids intake and body mass index (BMI). After adjusting for potential confounders, serum levels of ghrelin in CC genotype patients were significantly higher than T allele carriers (p = 0.03), whereas the case with leptin did not reveal a significant difference. The result of this study confirmed the interaction between APOA2 −256T>C polymorphism and SFAs intake with BMI in type 2 diabetic patients. In fact, homozygous patients for the C allele with high saturated fatty acids intake had higher BMI. The APOA2 −256T>C polymorphism was associated with elevated levels of serum ghrelin.     

The Physiological,Biochemical, and Molecular Modifications of Chickpea (Cicer arietinum L.) Seedlings Under Freezing Stress

Journal of Plant Growth Regulation - Fall cultivation of field crops such as chickpea is prone to the risk of freezing stress. It is required to identify the mechanisms through which plants can...     

Electronic properties and stability phase diagrams for cubic BN surfaces

This contribution investigates structural and electronic properties as well as stability phase diagrams of surfaces of the cubic boron nitride (c-BN). Our calculated parameters for bulk c-BN agree reasonably well with both experimental and computed values available in the literature. Based on the energies of the three experimentally recognised phases of bulk boron, i.e. α-B₃₆, β-B₁₀₅ and γ-B₂₈, we estimate enthalpy of formation of c-BN to be ?2.8 eV. The c-BN(1?0?0) surface offers separate B and N terminations (denoted as c-BN(1?0?0)_B and c-BN(1?0?0)_N), whereas c-BN(1?1?1) and c-BN(1?1?0) are truncated with combinations of boron and nitrogen atoms (denoted as c-BN(1?1?1)_BN and c-BN(1?1?0)_BN). Optimised geometries of surfaces display interlayer displacements up to the three topmost layers. Downward displacement of surface boron atoms signifies a common geometric feature of all surfaces. Bulk c-BN and its most stable surface c-BN(1?0?0)_N possess no metallic character, with band gaps of 5.46 and 2.7 eV, respectively. We find that, only c-BN(1?0?0)_B configuration exhibits a metallic character. c-BN(1?1?0)_BN and c-BN(1?1?1)_BN surfaces display corresponding band gaps of 2.5 and 3.9 eV and, hence, afford no metallic property.