These are lepidoptera larvae, as well as adult weevils of otiorhunchus species and other coleoptera, appearing during this period and feeding at night upon the outer edges of leaves, completely damaging them. Their activity can be later extended to juvenile vegetation. During years, when their presence is heavy, the damage they cause on the outer edges of leaves, and, thus, the production, can be considerable. During this period, the regular inspection of buds and vinestocks is recommended, in order for the damaged buds, as well as any larvae, to be traced. In case of infestation, such inspection is recommended also at nights, in order to detect a potential presence and activity of adult weevils (beetles) of otiorhunchus species. It should be noted, that otiorhunchus species are active during the night. In case that the buds were affected the year before, the inspection should be carried out at least twice a week during this period. In case of a confirmed infestation, the immediate application of a proper and approved insecticide is recommended. If any presence of otiorhunchus species is detected, the application should be carried out at night. Since an infestation usually occurs at the vineyards, the spraying of the infected vinestocks alone, their neighbouring ones, as well as the surface of the ground around the throat of the plant is recommended.
MITES: COLOMERUS VITIS – CALEPITRIMENUS VITIS
They are very tiny vermiform mite species of the genus Eriophyidae. From the bud scales to the shoots, they cause necrosis of the buds and strong malformation of the stems and leaves. Measures to combat these herbivorous mites are usually unnecessary, since they are effectively controlled by natural enemies (Phytoseiidae and thrips). Strong malformation of the young roots due to the vermiform mite species Eriophyidae. In the case, when considerable damages (mainly necroses of buds and strong malformations of stems and leaves) have occurred during the previous growing period, the taking of measures is recommended. These measures involve spaying with 1% wettable sulfur at the bulge of the bud. Following the budburst and for toxicity purposes, the rate should be reduced to 0,8-0,6%. This spraying is of significant importance, since latter interventions after the emergence of symptoms are proved to be ineffective. It should be noted, that this spraying has beneficial effect towards not only uncinula necator, but also phomopsis viticola and macrophoma flaccida.
Any appearance of thrips during the budburst can cause serious damages to juvenile and rapidly growing vegetation, as well as strong malformation of the stems and leaves and development freeze for emerging buds. During this period, the winegrowers should inspect their vineyards for a potential presence of thrips on the emerging vegetation. In case that an insect infestation had occurred during the previous year, then inspection is deemed necessary. It is also recommended that young stems be shaked gently and carefully over a white paper. It is preferable that the inspections are carried out randomly and throughout the vineyards during cool days. The inspections can be simplified through the use of a yellow adhesive trap per 0,3-0,4 hectares. A measure that contributes significantly to combating the thrips is the scrupulous destruction of the wild vegetation in and around the vineyards, since thrips have a large circle of hosts, many of which are parasites. In case that any presence of this population of thrips is detected, an immediate intervention by a proper and approved, preferably more selective and environmentally-friendly, insecticide is recommended.
PHOMOPSIS VITICOLA – MACROPHOMA FLACCIDA
They are closely related fungal diseases with similar symptoms. Μore favourable for cytospora to affect the juvenile vegetation is the period from the budburst until the stems reach a length of about 15cm. In vineyards and areas with a history of infection by these diseases, the carrying-out of precautionary spayings with a proper and approved fungicide is recommended. The first spaying shall be carried out during the budburst, the second one just after the formation of the first leaf and the third one at the stage, when 2-3 leaves have been emerged. The number of the interventions depends on the weather conditions and the variety susceptibility. Rainfall and relatively low temperatures contribute positively to the release of cytospora and disease infectiveness. A characteristic symptom of these diseases on tender vine shoots.
ATTENTION: In any case, the instruction for use of plant protection products shall be strictly followed, concerning the use rate, the blending, the risk for phytotoxicity, the time interval between the last intervention and harvesting and the protection measures for the prevention of food poisoning. All of our reports are available at the website of the Ministry of Agricultural Development and Food.
ΠΡΟΣΟΧΗ: Σε κάθε περίπτωση να τηρούνται αυστηρά οι οδηγίες χρήσης των φυτοπροστατευτικών προϊόντων για την αναλογία χρήσης, την συνδυαστικότητα, τον κίνδυνο φυτοτοξικότητας, το διάστηµα µεταξύ τελευταίας επέµβασης και συγκοµιδής και τα µέτρα προστασίας για την αποφυγή δηλητηρίασης. Όλα τα δελτία µας υπάρχουν στην ιστοσελίδα του Υπουργείου Αγρ. Ανάπτυξης & Τροφίµων στο διαδίκτυο.
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