Phytosanitary status of agricultural crops as of 09.01 Corn

During the first days of August, the agrometeorological conditions in Western Bulgaria remained unstable. This further hindered the wheat harvest and worsened the grain quality. By the end of the month, the wheat harvesting had still not concluded in the higher areas of the Kyustendil, Pernik, and Sofia provinces. In mid-August, the atmosphere stabilized, temperatures rose, and in different parts of the country the maximums reached between 33-38°C.

In the second half of August, part of the spring crops finished their development. The sunflower harvest and the rapeseed sowing began. In Southern Bulgaria, in areas with less rainfall during the season, the harvesting of early hybrid corn also started.

CORN

Phenophase: "early waxy maturity" – "full maturity"

European Corn Borer

Currently, harmful activity from the pest's second generation is being observed. The recorded density in the Vidin, Montana, Pleven, Plovdiv, etc., provinces is below the Economic Injury Level (EIL) and reached up to 25% infested plants (at EIL: grain corn – 90% infested plants by larvae with 3-4 damages per plant). The corn hybrids used in Bulgaria in recent years are capable of withstanding significant damage from the pest's larvae without this affecting the yield. Given the established low density, chemical control is not economically justified. Nevertheless, the optimal conditions for larval development during the summer months of this year, temperatures below 34°C and humidity of 70-100%, concerned farmers, and insecticide treatments against the second generation of the European corn borer were carried out on 163.6 thousand decares.

Cotton Bollworm

Damage from third to fifth instar larvae of the pest's second generation has been confirmed on corn cobs in the regions of Vidin, Vratsa, Plovdiv, and Targovishte. An infestation of 5 to 15% damaged cobs was recorded. Treatments were carried out on 163.6 thousand decares in the Vidin, Montana, Pleven, and Plovdiv provinces. The conducted sprayings were combined for simultaneous control against leaf aphids and the European corn borer.