Rotation: in general, peas should not be grown on the same land more often than
every 3–5 years, to minimise the increase of soil-borne pests and diseases.
Pests: these can cause big problems, both in the field and in storage:
- Pea Aphid—causes stunting and also transmits more than 20 different virus
diseases. Control: some varieties have some resistance, or spray with organo-
phosphorus insecticides, nicotine sulphate or rotenone.
- Pea Cyst Eelworm—plants are stunted, turn yellow and may die. Control is
difficult, and a crop rotation with a 10–12 year break is the only practical method.
safe, though parathion may also work.
cause big problems, and can be controlled with sevin or malathion.
Diseases: these can also cause large losses in yield:
on the leaves and sometimes on the stems and pods. Control: dust regularly with
sulphur, and crop rotation.
widespread and major problem. Control: use clean seed and/or 3–4 year crop
rotation.
- Pea Wilt—plants are stunted, with yellow leaves. Control: resistant varieties.
- Bacterial Blight—all plant parts above the ground show water-soaked lesions,
which can kill young plants, especially in humid conditions. No known control.
this disease. Sclerotia develop in the soil, and produce spores which infect bean
stems (and linseed, oilseed rape and spring beans). New sclerotia develop here and
interfere with the plants water conduits, so that all plant parts above the infection die
of “thirst”.
with resistant varieties; failing this, the aphid vectors must be destroyed.
- Deficiency diseases—Molybdenum is essential for nodulation of the roots.
Manganese deficiency, occurring mainly in alkaline soils, causes the seed centre to
darken (Marsh Spot).
YIELD
The yield of field peas varies enormously:
Dried Peas—2 MT/ha is considered satisfactory; 4–5 MT/ha is common in northern
Europe. Global average yield quoted by FAO for 2004 was 1.9 MT/ha, from a low
of 268 kg/ha in Croatia to a high of 5.8 MT in the Netherlands.
Green Peas—a good average yield of green peas in the pod is 6.5–7 MT/ha,
and 4.5 MT/ha of shelled green peas.
UTILISATION
ground into flour or made into soup. There is a huge industry for canning (both
green and dried peas), dehydrating and freezing peas. The grain is sometimes
also used for animal food, when its price is similar to cereals, either whole, split
or as flour. This practice is becoming more common in recent years, with GM
- Pea Weevil—larvae feed on the seed. Control: rotenone dust works well and is
- Pod Borer and Leaf-eating Caterpillar (Lesser Armyworm)—both of these can
- Powdery Mildew—this is the most widespread and serious. A white dust appears
- Ascochyta Blight (Leaf Spot, Pod Spot)—a seed-borne disease which is a
- Virus diseases—there are more than 20 of these, some of which can be controlled
Stem Rot (Sclerotinia sclerotiorum)— although not common, field peas may develop
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Dried grain (seed)—this is a valuable and nutritious food, which is often
GROWING FOOD – THE FOOD PRODUCTION HANDBOOK
