Abstract:

The mature embryo of Pinus ponderosa was used as explants to induce adventitious buds on GD、SH、MS and N₆ medium supplemented with 0.5～4.0 mg·L^-1 6-BA and 0～1.0 mg·L^-1 NAA.The results showed that the basic medium played a determinative role in initiating the adventitious buds. GD was best, SH better, and MS and N₆ worst. The optimal combination of the medium was GD with 0.5 mg·L^-1 6-BA,on which 55% of explants was induced,average rate of propagation was six,the highest was ten. Addition of NAA would inhibit the formation of adventitious buds.A proper amount of active carbon promoted the formation and elongation of adventitious buds. The adventitious buds of P. ponderosa were used to induce adventitious roots on GD、SH、1/2 SH media supplemented with different concentration of NAA and IAA. The results showed that the basic medium played a determinative role in initiating the adventitious roots. Neither GD nor SH induced adventitious buds to form adventitious roots. Adventitious root was induced by 1/2 SH, on which 2.2% adventitious buds formed adventitious roots. The better combination of the medium was 1/2 SH with 0.5 mg·L^-1 NAA, on which 3.3% adventitious buds formed adventitious roots. In this paper, the experimental result was reported that root was successfully induced from cultured embryo of P. ponderosa.

Key words: Pinus ponderosa, Mature embryo, Adventitious buds, Adventitious root