130 likes | 312 Views
Verticillium Wilt in the UK Project Update. Dr Peter Gladders ADAS UK Ltd. Review. History in the UK Disease surveys Effects on yield Varieties Management options. Introduction - Verticillium wilt. First confirmed in UK in 2007
E N D
Verticillium Wilt in the UKProject Update Dr Peter Gladders ADAS UK Ltd
Review • History in the UK • Disease surveys • Effects on yield • Varieties • Management options
Introduction - Verticillium wilt First confirmed in UK in 2007 Pathogen is Verticillium longisporum – specific for crucifers (mainly brassicas) Important in other parts of Europe with up to 50% yield loss Grey microsclerotia – key diagnostic feature Look for long streaks right up the stem – phoma similar Only evident late in season HGCA Research Review No 72 completed May 2009
Disease Cycle of OSR Verticillium Wilt Plant debris or soil from nearby infested fields
Disease Survey Samples – Variation by Field & Year Proportion of samples (fields) from Crop Monitor positive for V. longisporum Number of samples with various proportions (%) of stems positive
Distribution of Verticillium Wilt 2009-2011 Factors affecting distribution?
Yield Impacts Numerous reports of yield effects when crops ripen prematurely 2012 – significant yield impacts Single plants harvested from heavily infected crops Decreased TSW by 12-24% when verticillium affected >50% stem Further losses if seeds are shed
Varieties Differ in their Resistance to Verticillium Wilt LSD 10.2
Mean %verticillium by variety -Lincs 2010 & 2011(Limited variety experiments but main rankings have been consistent) LSD = 9.9
Managing Verticillium Wilt - Options Determine its prevalence on individual farms Good agronomy – a strong plant holds off verticillium Variety choice Extended rotations
HGCA Project reference RD-2009-3618 Importance and management of Verticillium wilt in winter oilseed rape ADAS UK Ltd, Warwick-HRI, FERA, Farmacy/Hutchinsons