Development of PCR assays to Tri7 and Tri13 trichothecene biosynthetic genes, and characterisation of chemotypes of Fusarium graminearum, Fusarium culmorum and Fusarium cerealis

Fusarium graminearum, Fusarium culmorum and Fusarium cerealis are major causal agents of Fusarium Head Blight (scab) which is a disease of global significance in all cereal growing areas. These fungi produce trichothecene mycotoxins, principally nivalenol (NIV) and deoxynivalenol (DON). Genes Tri13 and Tri7 from the trichothecene biosynthetic gene cluster convert DON to NIV (Tri13) and NIV to 4-acetyl-NIV (Tri7). We have developed positive–negative PCR assays based on these two genes, which accurately indicate a DON or NIV chemotype in F. graminearum, F. culmorum and F. cerealis. These assays are useful in assessing the risk of trichothecene contamination, and can be informative in epidemiological studies. All NIV chemotype isolates studied have functional copies of both Tri13 and Tri7, and all DON-producing isolates have both genes disrupted or deleted. We have identified several mutations in these genes, which are conserved across F. graminearum lineage, RAPD and SCAR groupings and between the three species. There appears to be evidence of inter-species hybridisation within the trichothecene biosynthetic gene cluster.     

Rural innovation systems and networks: findings from a study of Ethiopian smallholders

Ethiopian agriculture is changing as new actors, relationships, and policies influence the ways in which small-scale, resource-poor farmers access and use information and knowledge in their agricultural production decisions. Although these changes suggest new opportunities for smallholders, too little is known about how changes will ultimately improve the wellbeing of smallholders in Ethiopia. Thus, we examine whether these changes are improving the ability of smallholders to innovate and thus improve their own welfare. In doing so, we analyze interactions between smallholders and other actors to provide new perspectives on the role played by smallholder innovation networks in the agricultural sector by drawing on data from community case studies conducted in 10 localities. Findings suggest that public extension and administration exert a strong influence over smallholder networks, potentially crowding out market-based and civil society actors, and thus limiting beneficial innovation processes. From a policy perspective, the findings suggest the need to further explore policies and programs that create more space for market and civil society to participate in smallholder innovation networks and improve welfare. From a conceptual and methodological perspective, our findings suggest the need to incorporate rigorous applications of social network analysis into the application of innovation systems theory.     

Standard fare or fairer standards: Feminist reflections on agri-food governance

In 2007 new meat inspection regulations standardizing meat production throughout the Province of British Columbia (BC), Canada came into effect moving food for local consumption closer to continentally harmonized production standards. Critics argue that the economic viability of small-scale livestock farmers is threatened. Small-scale women farmers are central to the creation of alternative local agri-food networks in BC. Using gender as an analytically enabling tool this paper argues that public food-safety regulation can create the conditions for the dominance of private agri-food governance. The discursive creation of a feminized privileged consumer legitimates much non-democratic agri-food governance. The paper argues that more just and ecologically sustainable futures require a ‘gender troubling’ of agri-food governance in which the privileged identity of the food consumer is reconstructed as global citizen in the context of the food sovereignty of the farmers who produce their food.     

Chemical composition and antispasmodic effect of Casimiroa pringlei essential oil on rat uterus

The Casimiroa pringlei essential oil was analyzed to determine its chemical composition. Its effect on rat uterine smooth muscle was studied and compared with verapamil. Pure commercial piperitone, eucalyptol, and alpha-terpineol, the major constituents of C. pringlei essential oil, were tested on the uterine tonic contraction induced by high-potassium depolarizing solution (KCl 60 mM).     

Berries: Improving Human Health and Healthy Aging, and Promoting Quality Life—A Review

The importance of the diet in relation to human health has increased the interest of consumers on nutraceuticals rich foods, and especially on fruits and vegetables. Berries are rich sources of a wide variety of antioxidant phenolics; these phytochemicals include flavonoids, stilbenes, tannins, and phenolic acids. Reactive oxidant species and free radicals are produced in an extensive range of physiological processes. In addition to the antioxidant defenses produced in the body, there are exogenous sources supplied by the diet; this is the case of berry fruits, among others. The insufficiency of antioxidant defense mechanisms is associated to the pathology of chronic disorders such as cardiovascular diseases, inflammation, and diabetes. Therefore, the enforcement of the latter mechanisms is of the utmost importance. The isolation and characterization of compounds that may delay the onset of aging is receiving intense research attention; some berry phenolics are being associated with this functional performance. Berry phenolics may also act as antimicrobials which may be of help in the control of the wild spectra of pathogens, in view of recent problems associated with antibiotic resistance. Most of the research works on the antioxidant activity of bioactive constituents of berries has been carried out using in vitro assays. In view of this, the human studies investigating the bioavailability and potential toxicity of phenolics are receiving more attention. Finally, we would like to emphasize the necessity of associating new plant breeding and genetic studies of berries with the expression and overexpression of compounds for human health and healthy aging.