Peas can reap benefit from strobs
PEAS are set to reap similar benefits to strobilurin treatment as cereals do, following the approval of Amistar (azoxystrobin) for the pulse crop.
In company trials it has produced an average 27% yield response in combining peas when mixed with Bravo (chlorothalonil) in a two-spray programme, says Syn-genta technical manager Rod Burke.
Longer green leaf retention and improved disease control compared with current chemistry are claimed. However, there is no evidence of a delay in harvest date, he says.
For vining peas a one spray, stand-alone dose of 0.75-1 litres/ha is recommended. For the dry harvest crop the firm only recommends use with Bravo.
Although, FRAC guidelines would allow two applications of straight Amistar, from a resistance management point of view it is better to have two modes of action and the mixture provides more robust botrytis control, he says.
Cost of 0.5 litre/ha Amistar plus 1.5 litres/ha Bravo is expected to be £23/ha (£9/acre). That is much the same as a Ronilan (vinclozolin)/Bravo mix at the same rates, says Mr Burke. Both French and UK trials have shown about a 0.3t/ha (2cwt/acre) yield advantage from the strob regime.
• PGROs Anthony Biddle suggests a Ronilan-Bravo mix first to control pod rot or botrytis, then Amistar to give good control of leaf and pod spot – ascochyta. *