Somatic Embryogensis and Plant Regeneration from Immature Inflorescences of Hyparrhenia hirta (L.) Stapf

The study was conducted to determine an efficient system for in vitro culture and Hyparrhenia hirta, The effects of 2 different auxins (2,4-D and dicamba) at 3 concentrations (4.5 µM, 22,6 µM and 45,2 µM) and 2 ecotypes with different chromosome numbers (2n= 36 and 2n • 54) on callus induction and plantlet regeneration from immature inflorescences of Hyparrhenia hirta were investigated. Inflorescence segments of 5 mm length from greenhouse-grown plants were cultured on a modified Linsmaier and Skoog medium supplemented with 30 g/1 agar, Large differences In frequency of callus induction and callus weight were observed among lhe different ecotypes of Hyparrhenia hirta, but the regeneration rate was not influenced by ecotypes, Callus induction and callus weight were not affected by the ecotype chromosome numbers. The auxins tested were not statistically different In the effectiveness for lhe callus induction. Dicamba produced higher mean callus weights than 2,4-D, In contrast, 2,4-D was more effective than dlcamba for plant regeneration, and the highest averaged regeneration rate was obtained from the explants cultured on medium with 22.6 µM 2,4-D.