New Zealand Plant Protection 68 (2015): 389-395
The asexual form of the grape powdery mildew, Erysiphe necator, has been present in New Zealand for over 100 years. In 2013 the sexual stage was reported for the first time in vineyards in Hawke's Bay associated with increased disease issues. This paper presents an initial genetic analysis of New Zealand populations compared to known populations overseas and tentatively identifies two haplotypes new to New Zealand. Initial analysis of mating-type ratios indicates only one of these haplotypes is sexually reproducing. A better understanding of the fundamental character of the New Zealand populations of Erysiphe necator is needed before an accurate assessment can be made of the practical impact that the introduction of the sexual stage has had on disease incidence and control.
Keywords: grape powdery mildew, Erysiphe necator, population structure, chasmothecia.
|Sexual state of grape powdery mildew (Erysiphe necator) newly recorded for New Zealand|
P.R. Johnston, J.A. Cooper, D. Park, P.W. Sutherland and P.N. Wood (2014)
New Zealand Plant Protection 67: 324
Copyright © 2015 New Zealand Plant Protection Society (Inc.).