Study of the distribution and damage characteristics of mealybugs in vineyards under different ecological conditions of Azerbaijan

Considering the recent widespread occurrence of the mealybug, the distribution and harmfulness of the pest were investigated in the vineyards of Absheron, Gakh, Shamakhi, Samukh and Khojavend districts. In the Gakh district, the frequency of occurrence of the pest in the Sultani, Crimson seedless, Red Globe varieties was 86-97.0%, and the population density was 78.6-97.4%, which was higher than in other districts. In Absheron conditions, this pest is found in the perennial parts of the vines of other varieties, except for 4 out of 21 varieties (Moldova, Kyal uzum, Arna-grna, Medrese). The number of vines inhabited by the pest ranged from 3.03 (Kardinal) to 46.6% (Bandi). Although the settlement rate of the grape varieties studied in Absheron was relatively low, it was found that 3 varieties – Kardinal, Sabrani, Gara lkeni – were at a damaging level with a score of 2, and the other 14 varieties (Gyrmyzy merendi, Agadayi, Mahmudu, Ag tayfı, etc.) were at a high damaging level (26-90%) and within 3 points, depending on their population density or infection rate. The infection rate of the grape varieties studied in Khojavend and Shamakhi districts was low and was assessed at 1 point. The infection rate of the varieties in Samukh district varied, with no pests found in the Tabrizi variety, 2% in Rkasiteli, 8% in Khyndogny, and 12% in Bayanshira. According to our observations, one of the districts where the mealybug has developed more strongly in recent years is Salyan. The population density in the grapes inhabited by the pest is at a dangerous level, corresponding to 3 points and is 68.8% in Ag kishmish, 76.4% in Khalaj grapes, 78.4% in Ag Derbendi, 86.4% in Mahmudu, 90.3% in Ag shany, and 92.0% in Agadayi. Studies have shown that stems with strong development of the mealybug develop poorly, the color of the shoots weakens, the degree of shoots maturation and maturation coefficient are low, and this negatively affects the yield of the marketable product.