Laccases produced by Botrytis cinerea during infection of grape bunches can lead to wineoxidation and subsequent detrimental effects on wine quality. The role of laccases in thedevelopment of Botrytis bunch rot has not been fully elucidated even though the researchsuggests the involvement of three genes (LAC1, LAC2, LAC3) in laccase production by B. cinerea.The expression of these genes during infection by B. cinerea on grapes was examined by selectingone botrytis isolate (TN080) following an initial screening of virulence. Sterilized wine grapes(Chardonnay) were inoculated with a 10µl spore suspension (107spores∙ml-1) and incubated at24°C. Berries were collected at different time intervals post-inoculation, frozen in liquid nitrogenand total RNA extracted, followed by cDNA synthesis, RT-qPCR with primers designed for the threeLAC genes. Relative gene expression was normalized to the internal control, actin. Laccase enzymeactivity was also assessed in berry extracts collected at the same time and expressed as U∙ml-1. Allexperiments were done using three biological replicates. The expression of LAC3 was greatest (15fold) at one day post-inoculation and reduced gradually up to day 3. No expression of LAC2 andLAC1 genes were observed. Despite this gene expression, laccase enzyme activity in infected berryextracts was not observed until 3 days post-inoculation. The expression pattern of laccasetranscripts implies the involvement of the LAC3 gene in disease development. LAC3 may also be adeterminant of virulence during the infection of B. cinerea on grapes. This study implies thatlaccases may be important during the early stages of B. cinerea infection on grape berries.
|Number of pages||1|
|Publication status||Published - 2016|
|Event||XVII International Botrytis symposium - Santa Cruz Plaza Hotel, Santa Cruz, Chile|
Duration: 22 Oct 2016 → 27 Oct 2016
|Conference||XVII International Botrytis symposium|
|Period||22/10/16 → 27/10/16|