Determination of the fluorescence spectrum of botrytis cinerea pers.:Fr. isolated from highbush blueberry (vaccinium corymbosum L.)

Abstract

The prompt diagnosis of an attack by phytopathogens associated with the deterioration of the quality and condition of highbush blueberry is of great interest, particularly when dealing with Botrytis cinerea in preand postharvest stages. Real-time technologies that complement traditional diagnostic methods during the processing, storage and transport of fruit are advisable. The aim of this study was to determine the fluorescence spectrum of the B. cinerea mycelium in culture medium as well as its temporal variation. Two evaluations were conducted daily for 18 days using a fluorimeter with a 100 mW, 405 nm laser light, which excited the mycelium of each of five isolates of B. cinerea in two fixed positions. The fluorescence emission of the malt agar culture medium and the emission obtained from the fungus Trichothecium roseum were quantified for comparative reference. It was found that B. cinerea fluoresces mainly in the red-infrared area of the spectrum and T. roseum does so with greater intensity in the green-red segment. The energy of the fluorescence spectrum did not vary significantly according to the development of the B. cinerea mycelium in artificial culture medium.