不同pH条件下IBA和NAA对伴矿景天生根的影响研究

Effect of IBA and NAA on Root Development of Sedum plumbizincicola Under Different pH

为解决酸性环境中伴矿景天扦插苗生根难的问题,以河沙为基质,研究不同pH条件对伴矿景天扦插生根的影响,并进一步探究不同浓度吲哚丁酸IBA和萘乙酸NAA处理对酸性逆境环境下伴矿景天扦插苗生根的影响。结果表明:pH 5.5时,扦插苗虽能正常生长,但长势欠佳,当pH≤5.0时,植株根系发育不良,茎细短、叶片小,生物量不到正常生长(pH 6.5)时的40%,且pH越低植株死亡越快;用0.5~10.0 mg/L浓度的IBA和NAA溶液浸泡伴矿景天扦插苗可显著提高扦插苗成活率,主要表现为生根时间短、根系长、数量多。研究表明,pH≤5.0的扦插环境不利于伴矿景天扦插苗生长,扦插前使用浓度分别为2.0~3.0 mg/L和1.0~2.0 mg/L的IBA和NAA溶液浸泡伴矿景天扦插穗基部,可缩短扦插苗在酸性环境中生根时间、增加根系数量和根系长度,提高成活率。

To solve the negative impacts of the acidic environment on rooting of Sedum plumbizincicola cutting seedlings, a sand culture experiment was conducted in artificial climate chamber. In this experiment,both the influence of different pH conditions on rooting and plant growth of cutting seedlings and the effects of different concentrations of IBA and NAA on the rooting of cutting seedlings were studied. The results showed that, although cutting seedlings could grow normally, they did not grow well at pH 5.5. At pH≤5.0,the root system was underdeveloped, the stems were shorter and the leaves were smaller, eventually resulting in less than 40% of the normal biomass(pH 6.5), and the lower the pH, the faster the plant would die.Soaking the cutting seedlings with 0.5-10.0 mg/L IBA and NAA could significantly improve the survival rate through shortening rooting time and increasing rooting number and length. This research suggests that culture medium with pH≤5.0 is harmful to Sedum plumbizincicola cutting seedlings’ growth. Soaking the base of Sedum plumbizincicola cutting seedlings with 2.0-3.0 mg/L IBA and 1.0-2.0 mg/L NAA before cuttage can shorten the rooting time, increase the number and the length of the root system, and improve the survival rate.