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In order to establish the preferred shopping places for food, consumers were asked to indicate what shop they traditionally buy their groceries from. Six places were identified from past research as: supermarket, spaza shops (which are common in rural areas), Grocery stores, Farmers markets such as the Kei Fresh produce in Mthatha or the farmers market in Wilsonia, East London, Street vendors or the farm gate. Respondents’ were free to mark all the choices. An overwhelming majority of the respondents, 96% in the Transkei and 89.4% in the Ciskei, indicated that they bought their food. | New Phytologist Research The major volatile organic compound emitted from Arabidopsis thaliana flowers the sesquiterpene E -p-caryophyllene is a defense against a bacterial pathogen Mengsu Huang1 2 Adela M. Sanchez-Moreiras2 Christian Abel2 Reza Sohrabi1 Sungbeom Lee1 Jonathan Gershenzon2 and Dorothea Tholl1 department of Biological Sciences Virginia Tech Blacksburg VA 24061 USA 2Max Planck Institute for Chemical Ecology 07745 Jena Germany Author for correspondence Dorothea Tholl Tel 1 540 231 4567 Email tholl@vt.edu Received 12 October2011 Accepted 3 November 2011 New Phytologist 2012 193 997-1008 doi 10.1111 j.1469-8137.2011.04001.x Keywords antimicrobial defense Arabidopsisthaliana bacterial pathogen E -p-caryophyllene floral volatile Pseudomonas syringae stigma terpene. Summary Flowers have a high risk of pathogen attack because of their rich nutrient and moisture content and high frequency of insect visitors. We investigated the role of E -p-caryophyllene in floral defense against a microbial pathogen. This sesquiterpene is a common volatile compound emitted from flowers and is a major volatile released from the stigma of Arabidopsis thaliana flowers. Arabidopsis thaliana lines lacking a functional E -p-caryophyllene synthase or constitutively overexpressing this gene were challenged with Pseudomonas syringae pv. tomato DC3000 which is a bacterial pathogen of brassicaceous plants. Flowers of plant lines lacking E -p-caryophyllene emission showed greater bacterial growth on their stigmas than did wild-type flowers and their seeds were lighter and misshapen. By contrast plant lines with ectopic E -p-caryophyllene emission from vegetative parts were more resistant than wild-type plants to pathogen infection of leaves and showed reduced cell damage and higher seed production. Based on in vitro experiments E -p-caryophyllene seems to act by direct inhibition of bacterial growth rather than by triggering defense signaling pathways. E -p-Caryophyllene thus appears to
