Sunday 27 May 2012
Headlines
Did you find this story interesting? (0) (0)
20/06/2005
Mix fungicides to match mildew pressure in onions
The first signs of Downy Mildew infection have recently been identified in spring set onion crops, and disease is predicted to quickly move into spring drilled crops, now at the four to five true leaf stage.
Andy Richardson of the Allium & Brassica Centre reports high disease pressure in overwintered crops. Whilst relatively cold, dry conditions in April and May held significant early-season mildew attacks at bay, current warm, showery weather has increased spore production and disease pressure, he warns.
With the increasing problems of Downy Mildew over recent years, Mr Richardson now advocates growers use a fungicide mixture for each spray throughout the season, aiming to provide both eradicant and preventative properties with each application.
"Previously growers would typically start the programme with two or three applications of preventative Bravo (chlorothalonil), before switching to an eradicant mid-season. We now know mixing Bravo with Invader (dimethomorph + mancozeb), and alternating that with a powerful Folio Gold + Amistar mix, gives the best chance of keeping disease out of the crop," he advises. Crops will typically receive three applications of each mix in a six-spray programme.
If any Downy Mildew lesions are identified at an early stage, he recommends the two eradicants - Folio Gold (chlorothalonil + mefenoxam) plus Invader - can be mixed as a double hit, with the aim of drying up lesions before they become established.
Mr Richardson highlights the warm showery weather conditions since late May that have brought Downy Mildew back with a vengeance in the over-wintered crop. Although it will have little effect now - the crop is currently being harvested and destined for processing - infection of spring crops could have serious consequences for skin quality and yield, as well as providing an entry point for damaging bacterial and neck rot infections. The mixed programme with Bravo and Amistar should prevent Botrytis leaf spot and reduce Cladosporium leaf blotch infection, he adds.
Spray interval timing will be dictated this season by disease pressure warnings from Warwick HRI, linked to in-field weather monitoring. Mr Richardson believes spray intervals may be extended to a maximum of 14 days in settled, dry conditions, but will be reduced down to seven days when infection risk is high.
With the UK onion crop area down by around 17% this year, he calculates home production is likely to match demand at around 400,000t, assuming average rainfall. With similar acreage cuts across Europe, after massive overproduction and poor prices in 2004/5 there is potential for better prices and returns for UK growers this season.
 |
Andy Richardson of the Allium & Brassica Centre reports high disease pressure in overwintered crops. Whilst relatively cold, dry conditions in April and May held significant early-season mildew attacks at bay, current warm, showery weather has increased spore production and disease pressure, he warns.
With the increasing problems of Downy Mildew over recent years, Mr Richardson now advocates growers use a fungicide mixture for each spray throughout the season, aiming to provide both eradicant and preventative properties with each application.
"Previously growers would typically start the programme with two or three applications of preventative Bravo (chlorothalonil), before switching to an eradicant mid-season. We now know mixing Bravo with Invader (dimethomorph + mancozeb), and alternating that with a powerful Folio Gold + Amistar mix, gives the best chance of keeping disease out of the crop," he advises. Crops will typically receive three applications of each mix in a six-spray programme.
If any Downy Mildew lesions are identified at an early stage, he recommends the two eradicants - Folio Gold (chlorothalonil + mefenoxam) plus Invader - can be mixed as a double hit, with the aim of drying up lesions before they become established.
Mr Richardson highlights the warm showery weather conditions since late May that have brought Downy Mildew back with a vengeance in the over-wintered crop. Although it will have little effect now - the crop is currently being harvested and destined for processing - infection of spring crops could have serious consequences for skin quality and yield, as well as providing an entry point for damaging bacterial and neck rot infections. The mixed programme with Bravo and Amistar should prevent Botrytis leaf spot and reduce Cladosporium leaf blotch infection, he adds.
Spray interval timing will be dictated this season by disease pressure warnings from Warwick HRI, linked to in-field weather monitoring. Mr Richardson believes spray intervals may be extended to a maximum of 14 days in settled, dry conditions, but will be reduced down to seven days when infection risk is high.
With the UK onion crop area down by around 17% this year, he calculates home production is likely to match demand at around 400,000t, assuming average rainfall. With similar acreage cuts across Europe, after massive overproduction and poor prices in 2004/5 there is potential for better prices and returns for UK growers this season.
No Comments
Nobody has posted any comments on this story.
|
Farming items for Sale
|
Deutz Agrofarm 100 - Stirling(GBP 31800)
Same Silver 90 - Darlington(GBP 13500)
John Deere - 7930 - Byfield
(Price on Application)
(Price on Application)
John Deere - 8530 TRACTOR - Norwich(GBP 91000)
Landini R85 2wd - Omagh(GBP 9000)
Related News
Mildew fungicide flexity offers bonus of useful reduction of eyespot - 22 Jan 2004This season, cereal growers in the UK are to be the first in the world to benefit from a new, powdery Mildew fungicide with a unique mode of action th...
Managing mildew – an essential need for sugar beet fungicide programmes this year - 24 Jun 2007Powdery mildew is by far the most yield damaging disease in sugar beet, causing up to 20% yield loss. It adversely affects yield by draining the plant...
Crops are set up to benefit from three-pronged fungicide mix at flag leaf - 17 May 2006BE sure to monitor crop growth closely over the coming weeks in order to achieve correct spray timings for forthcoming flag leaf (T2) fungicides, whea...
Olympus mounts new high for onion disease control - 11 Apr 2008A new vegetable fungicide with a unique crop-safe formulation provides onion growers with exceptional broad-spectrum disease activity. Olympus is in a...
New SOLA’s for Quell Flo on poppies, bulb onions and shallots - 02 Sep 2008The protectant mancozeb fungicides Quell Flo and Laminator FL have new SOLA's for use on poppies grown for morphine production, bulb onions and sh...
New Off-label Approvals for Flumioxazin in carrots, parsnips and bulb onions - 05 May 2009The residual and contact-acting herbicide, flumioxazin, available as SumiMax, Digital and Guillotine, has several new and significant off label approv...
Know your onion SOLAS - 06 Jun 2009Without the current range of Specific Off-Label Approvals (SOLAs) now available for onions, UK growers would not be in a position to grow this crop, a...
Time to consider applying Fazor in onions - 29 Aug 2009Growers are reminded that Fazor (maleic hydrazide) is approved for use on bulb onions in order to suppress internal sprouting in-store. Its use maint...
Onion variety ‘Vision’ wins NIAB Award - 25 Nov 2009The National Institute of Agricultural Botany has awarded its Variety Cup to the onion variety Vision bred by Syngenta Seeds. NIAB chief executive ...
Dacthal granted SOLA for salad onions - 29 Jan 2010Growers now have a new option for pre emergence weed control with the granting of a specific off-label approval (SOLA) for the use of residual herbici...
