RAPID MICROPROPAGATION OF HYBRID WILLOW (SALIX) ESTABLISHED BY OVARY CULTURE

A hybrid between Salix fragilis (female) x Salix lispoclados (male) wa s established by ovary culture. The hybrid seedlings were grown on Sch enk and Hildebrandt (SH) semi-solid medium containing 0.2 mg/L 6-benzy ladenine (BA). Shoot multiplication from nodal cuttings of in vitro hy brid seedlings was achieved on semi-solid Woody Plant (WP) medium with 0.2 mg/L BA. The shoot proliferation could be enhanced to 5-fold upon transfer of shoots to liquid WP medium supplemented with 0.2 mg/L BA and incubation on a rotary shaker. Shoots became hyperhydric and devel oped smaller and less expanded leaves when they remained in liquid med ium. Shoot vigor was restored upon transfer to semi-solid medium. Best rooting response of in vitro shoots was achieved on SH medium without hormone. The hybrid plantlets were successfully grown in the field.