Forced to change tack for effective weed control in pulses‏

Pea and bean growers are facing enforced change to their weed control programmes this year, as a consequence of the loss of a number of key active ingredients. But Agrovista has been devising new and effective herbicide programmes that will suit most situations and control the most difficult weeds, according to Dr. Mark Palmer, Technical Manager of Agrovista.

Mark points out that growers have lost several popular and effective pulse herbicides this year. "Cyanazine, fomesafen, simazine and terbutryn have all had their use revoked and so we need to look for effective alternatives."

According to Dr. Palmer, one useful alternative is the residual herbicide, Nirvana. Containing imazamox and pendimethalin, Nirvana was introduced to the UK market last year and is recommended pre-emergence in all varieties of vining peas, combining peas, winter and spring beans. "We have seen excellent results from Nirvana in both beans and peas, particularly when used with the specialist pre-emergence adjuvant system, Grounded. Grounded works by reducing spray drift, improving spray deposition pattern and increasing adsorption onto soil particles, which keeps the herbicide where it should be. This results in better performance and improved reliability of residual herbicides."

Mark reports that in BASF trials in spring beans the addition of 0.2 l/ha of Grounded to 4.5 l/ha of Nirvana applied pre-emergence improved the control of Black-bindweed by an additional 8% to 100%, Redshank by 4% to 100%, and Orache by 2% to 100% control.

Mark Palmer will be recommending Nirvana at dose rates of between 3.0 to 4.5 l/ha according to soil type when used alone or at 2.5 l/ha in mix with 0.25 l/ha of Cirrus CS (clomazone) and Grounded for improved control of Cleavers, Fools Parsley, Shepherds Purse and Groundsel in spring field beans and combining peas. In vining peas Nirvana will be recommended at 2.5 l/ha with Grounded.

"When it comes to peas, Nirvana and Grounded is the preferred pre-emergence option and once again the addition of Grounded has been shown to lift the control of some difficult weeds, including Black-bindweed, Redshank and Orache," reports Mark.

"It looks to be a more normal year when it comes to seedbeds and soil moisture and growers should be in a good position to get their pulse crops in and their pre-emergence herbicides on. Last year the dry soils made life more difficult for residual herbicides to work to best effect," reminds Dr. Palmer.

"Nirvana controls the most important weeds in peas and beans, including Black-bindweed, Charlock, Common Poppy, Fat-hen, Knotgrass, Orache and Redshank as well as Common Chickweed, Fumitory, Henbit Dead-nettle, Speedwells, Red Dead-nettle and Scarlet Pimpernel. Imazamox enhances the control of several key weeds, such as Charlock, Black-bindweed, Cleavers and Volunteer Oilseed rape, compared with equivalent rates of straight pendimethalin. Nirvana as a consequence offers a broader weed spectrum than straight pendimethalin," explains John Young, BASF Legume Product Manager.

Background Notes - Nirvana contains 16.7 g/l of imazamox and 250 g/l of pendimethalin, formulated as an emulsifiable concentrate, packed in 10 litre containers. It is recommended in combining peas, vining peas, spring field beans and winter field beans for the control of broad-leaved weeds including Black-bindweed, Charlock, Common chickweed, Common Field Speedwell, Common Fumitory, Common Poppy, Fat-hen, Henbit Dead-nettle, Ivy-leaved Speedwell, Knotgrass, Orache, Red Dead-nettle, Redshank and Scarlet Pimpernel. Nirvana is applied pre-emergence of the crop at a dose rate between 2.5 – 4.5 l/ha in 200 – 300 litres of water per hectare, with the dose rate depending on the crop, weed pressure, weed spectrum and length of persistence required.