VARIABILITY OF SUNFLOWER HEAD/CAPITULUM BY NEW MORPHOLOGICAL CHARACTERS

New studies on the morphological characteristics of sunflower plants could provide new systems and directions in the complex progress of the future improvement of hybrids. Through the complex (Encheva & Shindrova, 2014) and wide genetic dowry together with the concrete cultivation conditions of the sunflower, the characteristic expression of the plant morphology takes place. In the recent improved Hysun 162 IT hybrid, some new characters were found, specific to the semi-early maturity group. Thus, the diameter of the sunflower head/capitulum had an average of 17 cm. The weight of the sunflower head was 105 g together with the achenes produced and only 39 g empty head, without achenes. The average of number of achenes/ head was 1470, and their weight was 65 g. The percentage of empty achenes was 2-3%, and the mass of one thousand seeds was on average 44 g. The seeds had a length of 10 mm and width of 5 mm. Positive correlations were generally obtained between the morphological characters of the sunflower head. Though this study carried out on the components of the heads of this new sunflower hybrid, a good adaptability to the current zonal agriculture was found.