Detection of Botrytis cinerea on Helianthus annuus (Sunflower)

摘要

This method was originally published in the ISTA Handbook of Seed Health Testing in 1981 as Working Sheet No. 44 prepared by C. Anselme and R. Champion, La Miniere, France. The method was incorporated into the newly revised Annexe to Chapter 7 in 2002from the 1999 edition of the ISTA Rules. The method was reviewed by the ISTA-Seed Health Committee in 2006 (Cockerell & Koenraadt, 2007) with the recommendation to accept for a further five years. An ISTA Proficiency test for Method 7-003 highlighted problems with both over- and underestimation of Botrytis cinerea by laboratories. Confusion with saprophytes may have caused overestimation by some laboratories, while differences in the criteria as to when a seed is infected (presence of one conidiophoreversus soft rot on roots) led to underestimation of S. cinerea by some laboratories. The ISTA SHC agreed that an experiment be carried out to establish whether the use of a malt solution exacerbates the proliferation of saprophytes, leading to incorrectassessments by laboratories. The results showed when malt solutions of 1% and 3% were used, B. cinerea levels were significantly higher than the true value after 9 days' incubation, and also after 7 days with 3% malt. The malt solution was also shown toincrease the saprophyte count compared to no malt.