Embryogenesis and plant regeneration of the perennial pasture and medicinal legume Bituminaria bituminosa (L.) C.H. Stirton

Abstract

Bituminaria bituminosa (common name tedera) is a drought-tolerant perennial pasture species of agronomic and pharmaceutical interest for Mediterranean climates. Considering the importance of this legume, in vitro experiments were conducted to develop protocols for plant regeneration from embryogenic calli of leaves, petioles and anthers to efficiently exploit and maintain selected important clones from the tedera breeding program. The type of explant was a key factor in the frequency of embryogenesis and the number of embryos per callus. For plant regeneration from cultured anthers, appropriate anther physiological state (uninucleate stage of microsporogenesis), stress treatments (electroporation, 25 Ω, 25 µF, 1500 V) and culture conditions were determined. A robust flow-cytometry method was developed to analyse the ploidy status of callus, in vitro shoots and in vivo acclimatised plants derived from anther and leaf explants.