Callus cultures have been established from leaves and stem segments of perennial wild diploid species, namely H. giganteus L., H. trachclifolius Miller, H. nuttalli Torrey et A. Grey and H. maximiliani Schrad. The calli originated from leaves were weak and did not give rise to embryos. Callus growth in stem segments was intensive with 5x10-6-10-5 M 2,4-D and NAA. The calli were maintained in subcultures at 3x10-6 M level of NAA. Regular embyoid and shoot fornation was achieved with 10-6 and 3x10-6 M NAA in combination with BA. kinetin, zeatin and 2iP (10-6-10-5M). The highest number of embryoids and shoots has been obtained in all four spcrcies on solidified medium containing 3x10-6 M NAA+5x10-6 M BA. In agitated liquid medium containing 10-6 M NAA+5X10-6 M BA abundant mass of cell aggregates was produced which in turn, plated on solidified medium with 10-6 M NAA+ 10-6 M BA (or kinetin or zeatin) +40 mg/l adenine + 30g/l sucrose, gave rise to hundreds of embryoids and shoot like structures. Rooted plants were transformed to greenhouse.

Efttet of nitrogen and phosporus nutrition applied to leaves was studied in field experiments at differents stages of development of sunflower during 1987-1988. In 1987, 5, 10, 15 and 20 kg/ha N and 5+5, 10+10, 15+15, 20+20 kg/ha N was used as chemical leaf fertilizer at the stage of budding and budding+10% flowering, respectively. In the next year, at budding stage all the plots were sprayed with dose of 10 kg/ha N as a basic treatment with the aim to incrcase the achene yield. At full bloom, these plots have additionally been treatedwith 1, 3, 5 and 7 kg doses of P for increasing the oil content. The greatest head diameter, achene yield/head and oil yield/head heve been achicved with doses 10 kg/ha (at budding stage) and 10+10 kg/ha N (budding+10% flowering stage). Achene oil content was decreased by treatments with N, whereas doses of P applied at full bloom had no effect on it. Effect of increasing N-doses may be fitted to a quadratic equation.