STUDIES REGARDING THE PRODUCTIVE POTENTIAL OF CERTAIN SUNFLOWER HYBRIDS IN THE CURRENT AGROPEDOCLIMATIC CONDITIONS OF THE DOBROGEA PLATEAU PUBLISHEDLiliana Panaitescu, Marius Lungu, Simona Niţă, Anca Nicoleta Albu, Georgeta Beleniuc, Mihaela Şonel, Florentina Malancu
According to FAO, sunflower is cultivated in 65 countries, being present on all the continents. The global surface cultivated with this plant is continually increasing. In 2002 it was cultivated on over 19 million ha, while in 2008 it was cultivated on over 25 million ha. The average international production is also on the increase (12.6 q/ha in 2002, 14.2 q/ha in 2008). In Europe, the situation is similar to the international one, both the cultivated surfaces and the productions obtained being on the increase. Taking into account the particular importance held by this plant at international and European level, this paper presents the behavior of certain sunflower hybrids, which exist in the official list of types and hybrids of cultivated plants in Romania. The paper follows the manifestation of the productive potential of this plant in the current agropedoclimatic conditions of the Dobrogea Plateau. It is known that sunflower has the highest water consumption from the occurrence of inflorescence to seed formation, when water consumption can rise to 5 mm/day and even more. From the calendar point of view, the critical phase in regards to water is in July and the first part of August. However, in Dobrogea Plateau, this period is poor in precipitations. Considering that all the technological elements contribute to the manifestation of the productive potential of a hybrid/type, but also that sunflower has the capacity to adapt to different environmental conditions and to high temperature oscillations (it resists at low temperatures, especially at the beginning of the vegetation period, as well as at drought), the paper refers to the manifestation of the productive potential of certain sunflower hybrids, depending on morpho-physiological characters, such as size, calathidium diameter, seed size or duration of the vegetative cycle, which depend to a large extent on temperature, photoperiod, humidity, but also agrotechnical means used. Knowledge of the reports between the vegetation factors and plants offers the cultivator the possibility, by means of the technical elements he has, to control, regulate and direct their action within certain limits, to provide the optimum conditions for the normal biological cycle and thus to obtain the estimated harvest.
floarea soarelui; hibrizi; potenţial productiv; condiţii agropedoclimatice