Phytosanitary status of agricultural crops as of 09/01 Potatoes

In the first days of August, the agro-meteorological 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. By 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 concluded 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.

POTATOES

Phenophase: mid-early – "harvesting"
late – "tuber growth" - "wilting of the haulm" The abundant and prolonged rainfall during the potato vegetation period increased the percentage of rotten tubers as a result of excessive soil moisture.

Colorado Potato Beetle
During the vegetation period, 1 to 4 treatments against the pest were carried out on 120.2 thousand decares. In the Plovdiv province, hatching of larvae from the third generation of the Colorado potato beetle was reported from August 8.

Potato Tuber Moth
In the Blagoevgrad, Kyustendil, and Sofia provinces, a weak flight of the pest's moths on pheromone traps persists. In the Blagoevgrad region, treatment was carried out on 1.0 thousand decares.

Subterranean Cutworms
The beginning of hatching of caterpillars from the second generation was established in the Blagoevgrad province, AER-Razlog. Damage to plant stems was confirmed in the Sofia province, AER-Samokov, where the recorded density was very high – 5 caterpillars/sq.m. Treatment was carried out on an area of 4.7 thousand decares in the regions of: Blagoevgrad, Kyustendil, and Sofia province.

Potato Late Blight
The rainfall at the beginning of the month created conditions for further incubation periods of potato late blight in late potato varieties and for an increase in the degree of attack by the pathogen.

The recorded degree of attack in the Blagoevgrad, Vratsa, and Pleven provinces is 5-25% attack on leaves (score 1-2). In the Smolyan region, the attack on leaves reaches 30-40% (score 3), and in individual areas in AER Razlog and Pernik, leaves are affected from 30 to 75% (score 3-4). Already upon lifting the early potato varieties, damage to tubers from blight was confirmed in individual crops in the Gabrovo, Kyustendil, Pazardzhik, and other provinces. During the lifting of potatoes in August, up to 15-20% attacked tubers were recorded in the Sofia province, and up to 30% in the Blagoevgrad region. 119.3 thousand decares were treated from 1 to 8 times.

During August, the spread of brown leaf spots (Alternaria) continued. Infected areas were registered with a degree of attack in the Blagoevgrad region from 3 to 10% and in the Smolyan region from 10 to 15%. 94.142 thousand decares were treated from one to six times.