Limiting factor for the development of late agricultural crops in August remains the deficit of soil moisture

In August, agrometeorological conditions will be determined by temperatures above the climatic norms and precipitation – around and below the monthly norm. The deficit of soil moisture will remain a limiting factor for the development of late agricultural crops in August as well.

The precipitation that fell at the end of July, following the deepening drought, was local and insufficient to overcome the moisture deficit in late agricultural crops. In most of the field regions, productive moisture is absent in the 50 and 100 cm soil layers.

During most days of August, the forecasted relatively dry weather will necessitate the application of increased irrigation rates for second crops and late maize hybrids. Increased irrigation rates will also be required for fruit trees, which are in the process of forming flower buds for the next year.

The new generation of sunflower hybrids from DAI is a highly intensive format for yield management

In August, earlier than the usual timeframes for the country, the development of late spring crops will be completed. At the beginning of August, in sunflower crops in Southern Bulgaria, technical maturity will be observed (Plovdiv, Haskovo, Sliven, Yambol), and at the end of the first and the beginning of the second ten-day period - also in the stands in a large part of the field regions. The earlier maize hybrids grown under irrigated conditions will enter wax and full maturity during the first ten-day period. The medium-late hybrids will complete their development in the third ten-day period of August. 

Due to the unfavourable agrometeorological conditions in the first half of the summer, with prolonged drought and extremely high temperatures, low yields of maize and sunflower are expected.

The persistently high temperatures in July, which will continue in August, seriously threaten the harvest of spring crops.

The only sunflower breeding centre in the country is the Dobrudzha Agricultural Institute, where breeding efforts are focused on creating new sunflower varieties resistant to broomrape, downy mildew and drought. One of the new hybrids of the Institute – “Dara”, suitable for cultivation using the “Express” technology and resistant to downy mildew up to race 731 and to broomrape up to race G, performs very well under conditions of drought and high temperatures.

In August, maximum temperatures in the range of 35–40ºC are forecast. These values will have a negative impact on flowering and fertilisation in vegetable crops from late production (cucumbers, green beans, courgettes).

The meteorological conditions during the month will limit the development of fungal diseases, with the exception of powdery mildews on vegetable crops, fruit trees and vines. An increase in mite populations is expected. In vineyards, it is necessary to monitor the density of caterpillars of the third generation of the European grapevine moth. Where necessary, plant protection spraying in August should be carried out during the cooler hours of the day (at temperatures below 25ºC), using products with an appropriate pre-harvest interval, in accordance with the ripening period of the crops.

Source: NIMH