THE YIELD AND OIL POTENTIAL OF SUNFLOWER HYBRIDS TESTED IN THE CZECH REPUBLIC

The aim of the publication is to evaluate results of introduced sunflower hybrids of foremost world breeders and to test their suitability for climatic and soil conditions in the Czech Republic. Large-scale and small-plot field trials were carried out in five localities. Concise results of hybrids location are brought in Tabs I - V. The 1991 trials have confirmed a high yielding level of hybrids Viki and Fundulea 206 which remain principal hybrids in the Czech Republic. Suitable for given conditions are also HNK 173, NS-8-52 and Davil. A low oil content was found in the hybrid Frankasol. Prospective hybrids needing a further verification are the Hungarian ones Union 55 and 74, Albena from Bulgaria, Pionier's hybrids Emil and Kamil, Northrup King's hybrids S 268 and S 281, as well as Cargill's SC 066 and AGC hybrids from the company Agrigenetic. Complementary characteristics (Tab. IV) prove a low oil content of Cargill's hybrids, mainly of Eurosol and Frankasol. The Oscar hybrid was the most affected by diseases. Among high yielding hybrids, there was a low affection: with diseases and at the same time, a high oil content in hybrids Union 55, Albena, Fundulea 206, Emil, Kamil and Davil, as well as in all the three AGC hybrids. The most productive among the Moldavian hybrids was MPK 8506. Hybrids with a high content of oleic acid xF produced by Pionier showed a good yielding ability, as well as a high oil content. Alimentary hybrid Toma remains for the Czech Republic the sole hybrid with achenes directly suitable for consumption. It is well resistant to diseases.