title: Suppression of Botrytis cinerea on necrotic grapevine tissues by early-season applications of natural products and biological control agents.
abstract: BACKGROUND
  Necrotic tissues within grape (Vitis vinifera) bunches represent an important source of Botrytis cinerea inoculum for Botrytis bunch rot (BBR) at harvest in vineyards. This research quantified the incidence of B. cinerea on necrotic floral and fruit tissues and the efficacy of biologically based treatments for suppression of B. cinerea secondary inoculum within developing bunches.
  
  
  RESULTS
  At veraison (2009 and 2010), samples of aborted flowers, aborted fruits and calyptras were collected, and the incidence and sporulation of B. cinerea were determined. Aborted fruits presented significantly higher incidence in untreated samples. Early-season applications of Candida sake plus Fungicover®, Fungicover alone or Ulocladium oudemansii significantly reduced B. cinerea incidence on aborted flowers and calyptras by 46-85%. Chitosan treatment significantly reduced B. cinerea incidence on calyptras. None of the treatments reduced B. cinerea incidence on aborted fruits. Treatments significantly reduced sporulation severity by 48% or more.
  
  
  CONCLUSIONS
  Treatments were effective at reducing B. cinerea secondary inoculum on necrotic tissues, in spite of the variable control on aborted fruits. This is the first report to quantify B. cinerea on several tissues of bunch trash and to describe the effective suppression of saprophytic B. cinerea inoculum by biologically based treatments.
authors.affiliation: Food Technology Department, Lleida University, XaRTA-Postharvest, Agrotecnio Center, Lleida, Catalonia, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Calvo-Garrido
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Viñas
authors.forename: Philip A G
authors.initials: PA
authors.lastname: Elmer
authors.forename: Josep
authors.initials: J
authors.lastname: Usall
authors.forename: Neus
authors.initials: N
authors.lastname: Teixidó
mesh_terms: D001203:Ascomycota / Q000502:physiology; D061046:Biological Control Agents; D001688:Biological Products; D020171:Botrytis / Q000187:drug effects*; D002175:Candida / Q000502:physiology*; D048271:Chitosan; D035264:Flowers; D005638:Fruit; D005659:Fungicides, Industrial; D010935:Plant Diseases / Q000382:microbiology / Q000517:prevention & control*; D013030:Spain; D027843:Vitis / Q000382:microbiology*
chemical_list: D061046:Biological Control Agents; D001688:Biological Products; D005659:Fungicides, Industrial; D048271:Chitosan
keywords: Candida sake CPA-1; Ulocladium oudemansii HRU3; Vitis vinifera; biological control; chitosan; floral debris