Cytokinins affect shoot regeneration and modulate the expression of IPT and CKX genes of in vitro cultured Eleocharis dulcis (Brum.f.) Trin

Abstract

ABSTRACT The Chinese water chestnut (Eleocharis dulcis (Brum.f.) Trin.) is conventionally propagated by underground corm with a lower propagation rate. In the present study, we attempted to develop a simple and efficient protocol for in vitro shoot regeneration, corm formation, and the generation of plantlets, on MS medium supplemented with BA, TDZ, NAA, and IAA. Additionally, the effect of BA on the expression of EdIPT and EdCKX genes was determined. The highest number of shoots (10.9) was produced by 0.5 mg/L BA, while that was the 0.1 mg/L TDZ (11.9), followed by the combination of 0.1 mg/L TDZ and 0.5 mg/L IAA (10.6), and shoot produced root spontaneously in these treatments. 60 g/L of sucrose was optimal for inducing the shoots while the highest corm number (5.8) was achieved by 90 g/L sucrose. 1.0 mg/L BA was optimal for corm formation with the highest number of corm (3.5) and the largest diameter (7.4 mm). NAA or IAA at 0.1 mg/L was optimal for rooting. Furthermore, we found the expression of EdIPT gene was up-regulated by the application of BA at a relatively lower level, and a high concentration of BA promoted expression of EdCKX gene.