Agrovista is advising bean and pea growers to find ways of getting the most from the pre-emergence herbicides that they intend to use, given that there are few post-emergence options available.
The chemical company has been looking at optimising herbicide programmes to suit most situations and to control the widest range of weeds possible, according to technical manager Dr Mark Palmer.
Growers have lost a whole range of pulse herbicides. “Familiar active ingredients such as cyanazine, fomesafen, simazine, terbutryn and now trifluralin are no longer available and so we need to look for effective alternatives,” said Palmer. “Most of these alternatives are pre-emergence as post-emergence options are restricted. We only have Basagran SG to rely on for post-emergence broad leaved weed control in beans.”
According to Palmer, one particularly useful alternative is the residual herbicide, Nirvana. Containing imazamox and pendimethalin, Nirvana is recommended pre-emergence in all varieties of vining peas, combining peas, winter and spring beans. “Nirvana provides a very comprehensive weed spectrum and we have been experimenting with it in order to achieve even better results and an even wider weed spectrum,” added Palmer. “Independent research and development work indicates that the specialist pre-emergence adjuvant, Grounded, helps the performance of Nirvana and other pre-emergence herbicides. Grounded improves the spray deposition pattern and increases adsorption onto soil particles, keeping the herbicide where it needs to be. This results in better overall performance and improved reliability of residual herbicides. It also reduces the risk of drift.”
Palmer reported that in BASF trials on spring beans, the addition of 0.2l per hectare of Grounded to 4.5l/ha of Nirvana applied pre-emergence improved the control of Black-bindweed, Redshank and Orache with the combination giving 100 per cent control.
Palmer has also investigated mixing Nirvana with other herbicides to make sure that the remaining weed species are adequately covered. “In spring field beans and combining peas, Nirvana at 2.5l/ha mixed with clomazone and Grounded gave improved control of Cleavers, Fool’s Parsley, Shepherd’s Purse, Groundsel and polygonums. We have also looked at Nirvana and Grounded with linuron. Previous dose response trials with linuron at 500g a.i/ha dose have demonstrated the additional control of weeds such as Chickweed, Hempnettle, Mayweeds and Small Nettle to the already comprehensive weed spectrum controlled by Nirvana.”
Palmer concluded: “With the high demand for protein and a lot more land available for spring cropping this year, we are anticipating a significant increase in the area of pulses being drilled, particularly spring beans. Day lengths are getting longer and hopefully we are due some dry weather, which will allow growers to get going with planting. One of their early priorities must be weed control. A well chosen pre-emergence spray applied under optimum conditions with an appropriate soil adjuvant will be the most cost-effective solution. One positive aspect of this year is that the soil will be sufficiently moist for residuals to work well.”
No comments yet