1- What is the piral of the vine?
According to the different areas, it receives different names such as “Papeletero”, “Sapo”, “Worm of the vineyard”, “Worm of the head”, … however the most widespread is that of “Piral”.
2- What are the symptoms it produces?
The most visible symptoms appear on the leaves. The oldest ones appear gnawed and pierced, with the middle and terminal part bent and as if glued by means of silk.
The underside becomes more visible and gives a silvery appearance to the vineyards with Piral attack.
In the clusters you can see glomeruli larger than those produced by the “moth”. The most important damages are those that it causes to the youngest leaves. From budding until just before flowering.
3- Biological cycle of la Piral.
The Piral at rest is 1 to 1.5 cm long and its visible wings have a straw-colored background crossed by dark bands. The coloration is more intense and the drawing much sharper in the male than in the female.
The laying of eggs is in small plates that look like drops of wax, with about 60 eggs placed in the bundle of the leaves closest to the trunk of the strain.
The coloration of these plastas is light green at first, evolves to dirty brown as incubation progresses and ends up being pearly white when the eggs have hatched. Newly hatched Piral larvae are yellowish in color, with a black head and about 2mm.
The monitoring of the cycle can be started at any time, but for practical purposes it is more advisable to start it at the time of laying and it looks very good and risk levels can be established for the following season.
The monitoring method already in spring consists of observing weekly (from the beginning of the vegetation) a determined number of strains (5-10) and carefully looking for the larvae.
4- Preventive measures and ecological treatments:
Observation of ooplacs in July and of larvae of the wintering generation in spring, on 4% of the strains.
Intervene to overflow if a threshold is reached higher than an average oplate per strain in those observed.
Use sexual traps to capture adults, in order to know the volume of the pest and its behavior.
5- Chemical control of La Piral:
Active matter recommended for treatments against Piral:
Some of these products may no longer be available on the market.