PGRO Crop Update (11.07.13)

Becky Ward, PGRO principal technical officer, gives the latest update on pests and diseases for peas and beans ...

PESTS

Bruchid beetles in beans
Bruchid beetles are still active in both winter and spring beans, although the risk in winter beans will be lower as flowering ends.

With current high temperatures, spring beans will be susceptible whilst flowers are still present at the tops of plants. Second sprays should be applied 7-10 days after the first.
 
Pea moth
Pea moth activity is still very high and peas remain susceptible to damage whilst pods are green. It is likely in many areas that second insecticide applications will be necessary and these should be applied 10-14 days after the first application.

Forecast spray dates can be obtained through the PGRO pea moth forecasting service on our website forum at www.pgro.org.

See PGRO technical update 149, available on the website, for details.
 
Aphids
Both pea aphid and black bean aphid colonies are present in crops and feeding impact may be high where crops are developing later than normal, particularly where temperatures remain high.

To prevent yield loss caused by direct aphid feeding, combining peas should be sprayed when around 20% plants are infested and vining peas when 15% plants are infested.

In beans, where a general infestation of 10% of plants are colonised, spraying should be carried out as soon as possible. Applications at early flowering or when 5% plants are infested reduces infections of aphid-transmitted viruses.
 
DISEASES

Disease risk in pea and bean crops remains low as the weather continues to be settled in most regions.