Duration of canopy protection required by spring barley post-anthesis
Experiments were conducted at two sites between 2009 and 2012 to investigate the duration of protection of canopy light interception required to maximise the yield of spring barley. Commencing at 50% ear emergence (Zadoks GS55), shades were erected at weekly intervals over disease-free plots to reduce incident radiation on the canopy by approximately 67% and left in place until harvest. The critical period requiring protection was between 3-5 weeks after GS55 (depending on the site-year) or approximately the first 75% of grain filling. Fungicide timing experiments showed that where disease pressure was low to moderate, a single application of prothioconazole plus pyraclostrobin at T1 gave sufficient canopy protection during grain filling to maximise yield. An additional T2 application at booting was required when disease was severe. Applications after ear emergence gave no further yield increase even though they resulted in a prolonged canopy lifespan, because the effects occurred late in the critical period.
Other Titles/Title of Conference
Crop Protection in Northern Britain - Environmental Management and Crop Protection, Dundee, UK
Journal Title/Title of Proceedings
The Dundee Conference: Crop Protection in Northern Britain 2014