Turkish Journal of Botany

Abstract: Vigna unguiculata is an important food legume crop in the semiarid tropics. It suffers from a host of agricultural constraints including damage due to diseases and pests. Judicious application of biotechnological methods can lead to considerable improvement in this important crop. Shoot regeneration from unsliced and longitudinally sliced cotyledon node explants obtained from 3-day-old to 5-day-old seedlings grown in vitro was achieved on Murashige and Skoog (MS) medium containing 1.11, 2.22, 3.33, and 4.44 mM benzylaminopurine (BA) supplemented with 1.0 mg/L polyvinylpyrrolidone and 500 mg/L bacteriostatic Augmentin. Callus induction was recorded in all culture media on both explants. The shoot regeneration frequency (%) of longitudinally sliced cotyledon node explants was 2-fold to 3-fold higher than that of unsliced cotyledon node explants. A maximum number of 9.92 shoots per longitudinally sliced cotyledon node explant was recorded on MS medium containing 3.33 mM BA. Each increase in the BA concentration of the culture medium proportionally decreased the mean shoot length on both explants. Maximum mean shoot lengths of 2.80 cm on unsliced cotyledon nodes and 3.04 cm on longitudinally sliced cotyledon node explant were recorded on MS medium containing 1.11 mM BA. Regenerated shoots were rooted on MS rooting medium containing 2.45 mM indole-3-butyric acid. In vitro regenerated plants were acclimatised at room temperature in growth rooms, where they produced viable seeds.

Key words: Auxin, cytokinin, in vitro, legume, micropropagation