Diyan Georgiev and Maria Georgieva
Agricultural Academy, Research Institute of Mountain Stockbreeding and Agriculture (RIMSA), 5600 Troyan, Bulgaria
Georgiev, D. & Georgieva, M. (2025). Vegetative and reproductive potential of some highbush blueberry varieties grown in the Troyan region. Bulg. J. Agric. Sci., 31(4), 702–708
The highbush blueberry is a fruit crop with specific requirements for agroclimatic conditions. Limiting factors for its distribution are its increased demands for atmospheric humidity and soil acidity. It thrives successfully in mountainous and semi-mountainous regions of the country, where there is a higher amount of precipitation, increased air humidity, and relatively favorable temperatures for realizing its biological potential.
The growth and development of five american varieties of highbush blueberries: Bluecrop, Bluegold, Patriot, Spartan, and Toro, were monitored in a demonstrative plantation at the RIMSA in Troyan, during the period 2020–2022. Under the agroclimatic conditions of the Pre-Balkans, fruit ripening of the studied highbush blueberry varieties begins from the second ten-day period of June, with no significant differences in timing between them. The quantity of plant pigments (chlorophyll a, chlorophyll b, and β-carotene) in leaf samples from the studied varieties was analyzed during the three-year experimental period. The highest levels of chlorophyll a and β-carotene in leaf samples were found in the second year of the experiment in the Patriot variety (1.31 mg/g and 0.83 mg/g, respectively).
The tallest average bush height was recorded in the Spartan varieties – 113.39 cm and Bluecrop – 110.11 cm during the experimental period.
The best results in terms of average yield were recorded in Toro (103.85 g/bush) and Bluecrop (99.94 g/bush).
The fruit weight had the highest average values in the Toro varieties – 1.69 g and Bluecrop – 1.45 g, while the fruits of the Spartan – 1.02 g and Patriot – 1.12 g varieties had the lowest weight.