Induction of morphogenically competent callus and suspension cell cultures from leaf explants and mature seeds ofDigitaria sanguinalis

Digitaria sanguinalis (crabgrass) has recently been introduced as a high quality forage crop. We report here a tissue culture system showing a high level of regeneration developed to aid in a breeding program. Two morphologically distinct types of callus, compact opaque and friable translucent, were induced from leaf blade explants and mature seeds when cultured on MS medium containing 0.9 μM 2,4-dichlorophenoxyacetic acid. Proline (25 mM) inhibited induction of callus but was required for continued maintenance. Plants were readily regenerated from the compact opaque callus. Selectively subcultured friable translucent callus continued to produce colony sectors of the morphogenically competent compact opaque callus when transferred to regeneration medium. Suspension cell cultures derived from callus or directly from leaf blade explants also produced regenerable callus.