几种影响沙棘组织培养外植体褐化因子分析

Factors affecting explant browning in tissue culture of Hippophae rhamnoides L.

为解决沙棘组织培养中易褐变死亡的问题,本研究通过对沙棘组织培养中外植体取材类型、无机盐浓度、光照和培养温度、不同的6-BA浓度、转接周期、培养基硬度以及活性炭7种影响外植体褐化因子进行分析。结果表明:选取沙棘水培2周以后休眠芽做外植体褐化率与取1年生枝条和2年生枝条作外植体的褐化率之间差异显著;使用1/4MS+6-BA 0.5 mg/L+NAA 0.2 mg/L的低盐和低6-BA浓度的培养基可以降低褐化且促进植株生长;接种后进行5 d的低温暗处理可以推迟褐变产生的时间,褐化率降低30%左右;在培养基中加入6～7 g/L的琼脂可使褐化率降低为12.67%,接种后在没有出现褐变物质前转接一次,然后慢慢延长转接时间比每14 d转接一次降低了30%,比每25 d转接一次降低了50%左右;附加1～2 g/L的活性炭可以减小褐变物的直径,推迟褐变始出物出现的时间,进而降低褐化率。

To control the browning and dying of the Hippophae rhamnoides L. tissue cultures, the analysis of seven factors which influence the rate of browning of explants, such as the concentration of inorganic salt, temperature and light, the different concentration of 6 - BA, the length of cycle, the hardness of medium and AC. The results indicate that the rate of browning was significantly different when we choose dormancy buds, which have been cultured in water for two weeks, and annual or biennial as explant respectively. The medium 1/4MS ＋ 6 - BA 0.5 mg/L ＋ NAA 0.2 mg/L reduces the rate of browning and promotes growth. Five days dark processing after inoculation delayed the time of browning, and the rate of browning reduced by 30% or so. After putting 6-7 g/ L agar in medium, the rate of browning reduced to 12.67%. Before browning occurs at the beginning, inoculation was performed first, then every fourteen days, when the rate of browning reduced by 30 %, and it reduced by 50 % while innoculation was done every twenty-five days. The adding of 1-2 g/L AC shortened the diameter of browning substance and delayed the exudation time of browning, so it decreased the rate of browning.