Rooting medium optimization of Carica papaya plantlets by using orthogonal design

Objective This research studied the different compositional effects of rooting medium on rooting induction of Carica papaya plantlets in order to provide references for further tissue culture and rapid propagation.Method Using the eighth generation tissue culture plantlets' lateral buds of the Carica papaya Tainong No.1 as test materials in this experiment,the plantlets were inoculated to the correspondent matching culture medium;different concentrations of IBA,NAA,and AC were applied as the rooting medium for rooting culture,and the best rooting medium were selected by using the orthogonal experiment design L9(34).Result In the MS,1/2MS,and 3/2MS culture medium,the rooting rate of plantlets showed significant difference,and the induction effects were ranked in the following order:MS1/2MS3/2MS.Different rooting rates of papaya with various IBA concentrations were ranked in the following order:2.0 mg/L2.5 mg/L 1.0 mg/L IBA and the optimal IBA concentration ranged between 2.0-2.5 mg/L.Different NAA concentrations on the rooting induction of papaya were ranked in the following order:0.05 mg/L 0.10 mg/L 0.00 mg/L,and the optimal concentration was 0.05 mg/L.The activated carbon effects on the rooting induction of papaya were ranked in the following order:0.002%0.005%0.000%,and the optimal concentration was 0.002%.Lastly,the MS culture medium,IBA,NAA,and AC on the papaya rooting rate were ranked in the following order:IBAACNAAMS culture medium.Conclusion The optimal medium combination for papaya rooting induction was MS+2.0 mg/L IBA+0.05 mg/L NAA+0.002% AC.