The cultivation of the grapevine, a pillar of Mediterranean agriculture, continuously faces new phytosanitary challenges. Among these, the presence of Cryptoblabes gnidiella, a polyphagous lepidopteran, is strongly emerging. Although not a classic major pest, it can cause significant damage if not managed properly.
What is Cryptoblabes gnidiella and how is it identified?
Cryptoblabes gnidiella is a small moth from the Pyralidae family. The adults are silver-gray, with a wingspan of about 12-15 mm. They are characterized by a light brown head and thorax and forewings with a distinctive pattern: a dark zigzag line. The most damaging stage for the crop is the larva, commonly known as a caterpillar.
The larvae, which vary in color from greenish to pink or brown, measure up to 15 mm and have a dark longitudinal band on their backs. These caterpillars are responsible for the direct damage to the grapes.
The biological cycle: key to effective control
The life cycle of Cryptoblabes gnidiella is typical of other lepidopterans: egg, larva, pupa, and adult. The adult females lay their eggs individually on the fruits or leaves. Once they hatch, the larvae go through five larval stages, during which they feed on the grapes. Pupation occurs inside a cocoon that the larvae weave on the fruit. The cycle’s duration depends on temperature and environmental conditions.
This lepidopteran has multiple generations throughout the year, which means its activity can extend through a large part of the growing season. The presence of the pest increases during the summer, with high temperatures, when it can coincide with classic grapevine pests like the grape berry moth (Lobesia botrana), which can make identification and management difficult.
Symptoms and damage from Cryptoblabes gnidiella
Unlike other pests that damage grapes from the outside, Cryptoblabes gnidiella larvae burrow into the inside of the berry or feed on the pulp. The main types of damage are:
- Perforation of berries: the larvae perforate the berries, causing juice loss and a damaged appearance of the bunch. This wound acts as an entry point for pathogens, especially fungi like Botrytis cinerea (gray rot) or Aspergillus.
- Webbing: one of the most characteristic symptoms is the presence of silky threads (webs) that connect the grapes and berries in the bunch. These webs, in addition to being a sign of infestation, hinder the action of phytosanitary treatments.
- Presence of droppings: the larvae leave behind black droppings, which are visible among the damaged berries.
Cryptoblabes gnidiella management and control strategies
Managing Cryptoblabes gnidiella requires an integrated approach, combining preventive and curative measures. Since its incidence can vary greatly, continuous monitoring of the pest is crucial.
1. Monitoring and detection
- Phytosanitary tools: the use of pheromone traps for adults is an effective tool for detecting the pest’s presence and monitoring the evolution of its populations. Identifying the first generation of adults is key to anticipating egg-laying and planning treatments.
- Field inspections: it is necessary to regularly inspect the grapes to detect the first symptoms of damage, such as webbing or perforations.
2. Biological control and sustainable measures
- Beneficial fauna: encouraging the presence of natural predators is fundamental in integrated pest management. Natural predators such as parasitoids and generalist predators help control Cryptoblabes gnidiella populations.
- Use of Bacillus thuringiensis (Bt): this bacterium is one of the most widely used bioinsecticides for controlling lepidopterans. Its selective action makes it an ideal option for sustainable agriculture, as it does not harm beneficial fauna or leave harmful residues. It should be applied preventively when the first caterpillars are detected.
3. Chemical control
- Selective insecticides: in cases of high populations, chemical insecticides can be used. It’s important to select products that are specific to lepidopterans and are highly effective against Cryptoblabes gnidiella.
- Application timing: the most effective time for applications is during the egg-laying phase or at the beginning of the larval hatching (L1-L2 larval stages), before the caterpillars enter the berries.
At Agroborges, we work alongside farmers to offer effective solutions adapted to each farm. Contact our technical team to establish a Cryptoblabes gnidiella control plan.
