Pest · pea

Pea beetle

Bruchus pisorum (Linnaeus)EPPO code BRCHPI

Ukrainian: гороховий зерноїд · Держпродспоживслужба, НААН, НАН
English: pea beetle · European and Mediterranean Plant Protection Organization

How to recognise it

Damage: The larva lives inside the pea. Before pupating, it gnaws a ring-shaped groove and so prepares an exit hole for the young beetle.
During pea flowering, the beetles feed on pollen and petals.
The damage is spoilt grain: the larva eats out large cavities in it and destroys about half of the endosperm or more.

When to look: In spring and summer, legume crops are surveyed periodically to detect the pea weevil in time.
Colonisation of pea crops begins at the branching stage. In most oblasts, mass colonisation is observed from budding to flowering.
How to count: Beetles in the crop are counted with a sweep net, recording the number caught per 100 sweeps.

Agronomy: Follow the crop rotation and sow resistant varieties. The pea weevil damages green-seeded varieties less than yellow-seeded ones.
Harvest early and within a short period. Immediately after harvest, carry out stubble cultivation and deep autumn ploughing.
Thoroughly clear threshing sites of plant residues. Use up pea chaff, straw and oat-legume hay before the beetles emerge.
Early trap sowings of peas make it possible to destroy the pest on a small area.
Seed damaged by the pea weevil and the pea moth is unfit for sowing.
Destroying the debris and plant residues that build up where grain legumes are dried and threshed limits the number of beetles going into overwintering.
Stubble cultivation and deep autumn ploughing of fields where annual grain legumes were grown reduce the pest population.
Biological control: It is worth sowing phacelia around the pea field: it helps build up effective parasites of the pea weevil.

Harvest quality: Larval excrement contains the alkaloid cantharidin, so damaged grain cannot be used as food or as livestock feed.
Damaged seed loses its germination capacity.

Favourable conditions: An optimal temperature of +24..+26 °C and moderate air humidity favour larval feeding, passage through the pupal stage and subsequent satisfactory overwintering.
Where it is found: It remains the most dangerous pest of peas everywhere.

Every fact rests on a quote from its source, and each quote was checked against the page it is printed on.

Зайцева І. А., «Сільськогосподарська ентомологія. Курс лекцій», навчальний посібник, 237 с. · Дніпровський державний аграрно-економічний університет, Дніпро, 2021 · p. 115, 119, 120
EPPO Global Database · European and Mediterranean Plant Protection Organization
Прогноз фітосанітарного стану агроценозів України та рекомендації щодо захисту рослин у 2025 році · Держпродспоживслужба, НААН, НАН · p. 71, 72
Photos: Malte, Wikimedia Commons, CC BY-SA 3.0 · nitsuga74, iNaturalist, CC BY 4.0 · John Green, CSIRO, Wikimedia Commons, CC BY 3.0

How to recognise it

Damage: The larva lives inside the pea. Before pupating, it gnaws a ring-shaped groove and so prepares an exit hole for the young beetle.
During pea flowering, the beetles feed on pollen and petals.
The damage is spoilt grain: the larva eats out large cavities in it and destroys about half of the endosperm or more.

When and with what to treat

When to look: In spring and summer, legume crops are surveyed periodically to detect the pea weevil in time.
Colonisation of pea crops begins at the branching stage. In most oblasts, mass colonisation is observed from budding to flowering.
How to count: Beetles in the crop are counted with a sweep net, recording the number caught per 100 sweeps.

Without chemicals, and prevention

Agronomy: Follow the crop rotation and sow resistant varieties. The pea weevil damages green-seeded varieties less than yellow-seeded ones.
Harvest early and within a short period. Immediately after harvest, carry out stubble cultivation and deep autumn ploughing.
Thoroughly clear threshing sites of plant residues. Use up pea chaff, straw and oat-legume hay before the beetles emerge.
Early trap sowings of peas make it possible to destroy the pest on a small area.
Seed damaged by the pea weevil and the pea moth is unfit for sowing.
Destroying the debris and plant residues that build up where grain legumes are dried and threshed limits the number of beetles going into overwintering.
Stubble cultivation and deep autumn ploughing of fields where annual grain legumes were grown reduce the pest population.
Biological control: It is worth sowing phacelia around the pea field: it helps build up effective parasites of the pea weevil.