摘要
In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundata, one D. cayenensis and two D. trifida). Medium S contained 0.6 μM benzyl adenine, 1.07 μM naphthalene acetic acid and 0.23 μM gibberellic acid while medium EBR contained 0.23 μM gibberellic acid and 0.1 μM 24-epibrassinolide. After 2 months of culture, oxidation level was significantly reduced on medium EBR compared to medium S for four of the five accessions tested. By contrast, medium EBR did not have any positive effect on shoot length since length of shoots produced after 2 months of culture on medium S and EBR were similar, except with accession 3-45T, for which shoot length was shorter on medium S compared to medium EBR. These results underline the potential of 24-epibrassinolide to reduce oxidation phenomena during in vitro culture and call for its utilization for regeneration of cryopreserved yam shoot tips, which is often impeded by oxidation phenomena.
In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundata, one D. cayenensis and two D. trifida). Medium S contained 0.6 μM benzyl adenine, 1.07 μM naphthalene acetic acid and 0.23 μM gibberellic acid while medium EBR contained 0.23 μM gibberellic acid and 0.1 μM 24-epibrassinolide. After 2 months of culture, oxidation level was significantly reduced on medium EBR compared to medium S for four of the five accessions tested. By contrast, medium EBR did not have any positive effect on shoot length since length of shoots produced after 2 months of culture on medium S and EBR were similar, except with accession 3-45T, for which shoot length was shorter on medium S compared to medium EBR. These results underline the potential of 24-epibrassinolide to reduce oxidation phenomena during in vitro culture and call for its utilization for regeneration of cryopreserved yam shoot tips, which is often impeded by oxidation phenomena.
