The effect of auxin type and cytokinin concentration on callus induction and plant regeneration frequency from immature inflorescence segments of seashore paspalum (Paspalum vaginatum Swartz)

Abstract

Seashore paspalum (Paspalum vaginatum Swartz) is a salt tolerant, fine textured turfgrass used on golf courses in coastal, tropical, and subtropical regions. A callus induction and plant regeneration protocol for this commercially important turfgrass species has been developed. Induction of highly regenerable callus with approximately 400 shoots per cultured immature inflorescence (1 cm in length) was achieved by culturing 0.2 cm segments on media with 3 mg l−1 3,6-dichloro-2-methoxybenzoic acid (dicamba) and 0.1 or 1.0 mg l−1 benzylaminopurine (BA). A multifactorial experiment demonstrated the combination of 3 mg l−1 dicamba and 1.0 mg l−1 BA for induction of callus resulted in 12 times higher plant regeneration frequency compared to 3 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) alone or ten times higher plant regeneration frequency than the combination of 3 mg l−1 2,4-D and 1.0 mg l−1 BA. These results are expected to support the development of a genetic transformation protocol for seashore paspalum.