In vitro morphogenic events in culture of Lotus corniculatus L. seedling root explants

Abstract

The experiments were carried out on Lotus corniculatus (L.) seedling root explants of the cultivar varieties Skrzeszowicka, Caroll A10 and strain 175. Callus formation and shoot regeneration were the major explant response depended mainly on of the studied genotype and used plant growth regulators (PGRs). Primary cortex of proximal and distal end of explant was the most active tissue for callus proliferation. For shoot primordia differentiation deeper zones of cortex took a part. The process of meristematic centre initiation was not uniform and various level of shoot differentiation events were observed not earlier than 3 weeks of culture. Usually, the shoot primordia regeneration began on proximal rather than distal end of the explant. BAP rather than urea derivatives stimulated shoot proliferation in extended cultures. Increasing of BAP and TDZ concentrations brought about the explant polarity and expansion of the meristematic zones. The explant position in root did not have significant influence on the number of regenerated shoots. The cultures only had better bud formation by TDZ when compared to BAP. BAP stimulated bud formation and development of the shoots from them. Short term of TDZ treatment of explants stimulated meristem formation which developed into buds and shoots. CPPU stimulated callus proliferation and bud formation when explants pretreatment was prolonged from 12 to 36 hrs.