An Efficient Regeneration System and Optimization of the Transformation from the Cotyledonary Node of Jute (<i>Corchorus capsularis</i> L.)

The purpose of this study was to use cotyledonary nodes as explants to establish an efficient regeneration protocol for jute (<i>Corchorus capsularis</i> L.) on Murashige and Skoog (MS) basal medium. Research into the different growth regulators using the orthogonal design L16 (4⁵) revealed that the best shoot induction medium is MS medium containing 8% (w/v) agar and 3% (w/v) sucrose supplemented with 1.0 mg/L 6BA and 0.25 mg/L NAA. The average number of shoots per explant and the explant induction rate were 9.8 and 100%. After 3 weeks, 2–3 cm shoots were rooting on 1/2 MS medium containing 8% (w/v) agar and 3% (w/v) sucrose supplemented with 1.0 mg/L 6-BA + 0.2 mg/L NAA. Moreover, we optimized <i>Agrobacterium</i>-mediated transformation using the <i>GUS</i> gene transient expression system. The best condition for obtaining higher transformation rate consisted of the use of fresh explants to which 100 μM acetosyringone was added for a co-culture time of 10 min, the OD value of <i>Agrobacterium</i> liquid is 0.5 at 600 nm. These data provide an important basis for the application of other trait gene in the improvement of jute fiber quality.