Insecta, Lepidoptera, Tortricidae .
Description, Biology, Life Cycle, Damage, Common Names, Images
- Host plant: vine but also Daphne gnidium, a wild plant extremely common to the south of France and which seems to be its original host, as well as ivy (Hedera), privet (Ligustrum vulgaris), black currant, currant.
- Adult: active at night, the moth can fly several hundred metres and looks for dry places. The flights take place when the temperature is at least 14°C but under 31°C.
Lifespan: 10 to 12 days. Mating begins at nightfall and egg laying starts 2 to 3 days later. The first generation eggs are laid on the flower bud, sometimes on the bracts, the vine-shoots or the leaves, those of later generations on the grains.
Fecundity: 40 to 60 eggs.
- Egg: development lasts 6 to 9 days for the first generation; it lasts only 4 to 6 days for the later generations, the temperature being higher.
- Larva: the first generation larva has a "strolling stage" of a few hours. After having slipped between 2 or 3 flower buds, it spins a few theads then perforates the flower envelopes and penetrates the bud (*) ; it may enter the peduncle of the bunch of grapes and cause the drying up of the bunch.
The caterpillar is active and spins a relatively large sheath, difficult to detect. The caterpillar of later generations move about for only a few minutes and attack fruits: they web several fruits together with silk threads then nibble them or penetrate them (*) .
- Pupe: development lasts 10 to 14 days. Overwintering occurs in the pupal stage, under the bark of the stump or in support-stake cracks.
- 2, 3 and sometimes 4 generations depending on the region and whether the summer has been hot.
- The moths appear from the end April until the end May depending on the regions, generally when the vine has 3 or 4 leaves. They emerge at intervals and the flights spread over 2 to 3 weeks. The caterpillar finishes its development at the time of flowering then pupates. The second flight takes place end of June-July; the more advanced caterpillars pupate and the third flight occurs between mid-August and the end of September.
Damage can be important: the caterpillars gnaw the almost ripe fruits and various moulds, in particular Botrytis, develop very rapidly on the wounds; the attacked fruits turn brown at the place of attack and rot (*) . The presence of larvae and rotten fruits lowers the quality of the crop; moulds render vine making difficult and may require the crop to be harvested prematurely.
HYPPZ on line : Species (scientific name), Pests (common names), Glossary, Crops.