Agri-Shop Ltd
Farminguk
30 April 2016 | Online since 2003
Auto Trader Ltd


19 September 2012 09:44:29|

Persistent pyrethroid needed for BYDV prevention


Exceptionally high levels of BYDV showed up in cereal crops earlier this year and the wet weather this summer has helped to create a green bridge of cereal volunteers and grass-weeds which is now acting as a reservoir for BYDV vectors.
This means that growers can expect significantly higher levels than normal of infection risk this autumn. A programmed approach will be needed with well-timed autumn applications of a persistent pyrethroid, even when an effective seed treatment is used, to prevent this yield-damaging virus getting into crops this autumn.
Dr. David Stormonth, Technical Manager for Interfarm UK, explains that there are two distinct approaches to the prevention of BVDV, depending on whether the crop has received a seed treatment or not. “The first approach is for cereals that haven’t had an insecticide seed treatment - this is most winter barley and around half of winter wheat crops sown. Autumn-sown crops with no insecticide seed treatment are at high risk from aphids causing BYDV infections from emergence onwards and will need treatment sooner rather than later with an effective pyrethroid.”
He explains that temperature is the key indicator for spray timing.
“Last autumn some foliar-applied aphicides were applied too late, hence the high incidence of Virus Yellows symptoms seen in the spring. It is a good idea to use the ADAS system of accumulated temperatures from crop emergence onwards when aphids colonise plants, in order to calculate when a foliar treatment is needed."
"This temperature-based system can also be used in cereals that have received a seed treatment to calculate when the follow up foliar-applied pyrethroid spray should be timed. In this instance the temperature calculation starts six weeks after sowing, rather than from crop emergence. This is because an effective seed treatment such as clothianidin gives around 6 weeks protection from drilling, not from crop emergence, as some think. Aphids can fly onto newly emerged crops at temperatures above 11°C.”
“To prevent the bird cherry aphid transmitting BYDV, an insecticide with rapid initial activity, good repellancy and long-lasting effects gives the necessary protection. Containing esfenvalerate, Sumi-Alpha offers the best persistence of all pyrethroids as well as having strong repellancy activity on aphids."
"High risk situations include early drilled crops, crops grown after grass or grassy stubbles, crops in the South and West, crops in sheltered fields close to hedges and coastal areas and in fields with green bridges of weeds and volunteers. For medium risk situations, a dose rate of 125 mls/ha can give four weeks protection and for low risk BYDV situations 100 mls/ha would give similar persistence to cypermethrin. Growers should ask their distributor for the right dose rate to suit the individual farm and field situations,” explains Dr. Stormonth.

Download





0 Comment


Name

Please enter your name


Email

Comment

Please enter your comment


Post Comment

Your comment submitted successfully.Please wait for admin approval.


Comments

No comments posted yet. Be the first to post a comment

World News

United Kingdom | 29 April 2016
Banned pesticides 'not equally harmful' to bees

The largest field study so far in to the group of pesticides called "neonicotinoids" has concluded that each acts differently on the brains of the bees. One of the chemicals widely considered as be...


Canada | 29 April 2016
Competing ethical meat standards leave Alberta beef farmers in crossfire

Colleen Biggs and her husband, Dylan, own an award-winning livestock operation in Alberta. TK Ranch produces beef without antibiotics, drugs, added hormones, animal by-products and chemical insecticid...


India | 29 April 2016
Govt plans to use quarter of farmland for horticulture

In a bid to gain from Haryana's close proximity to the national capital, the state government has planned to use major chunks of agriculture land for horticulture in the state. The state governmen...


Austria | 29 April 2016
Negative effect on Austrian agriculture

The trade agreement between the US and Europe, TTIP, will have negative effects on employment and the biggest losses in jobs will be in the agricultural and food producing sectors. This is one of ...


New Zealand | 29 April 2016
Suicide concerns rise for farmers as dairy downturn takes its toll

A rise in substance abuse and domestic violence in Golden Bay's rural community raises concerns over suicide as the dairy downturn continues to bite, mental health workers say. Community Mental Hea...



Trending Now

Viewed
Discussed

Farms and Land for sale


Holiday Rentals search



Top stories you may have missed
Username
Password