山木通扦插繁殖及生根机制

Cutting propagation technology and rooting of Clematis finetiana

以山木通Clematis finetiana 1年生枝条为材料,针对植物生长调节物质种类和质量浓度、浸泡时间、扦插基质等4个因素,采用L9(34)正交试验设计扦插试验,研究山木通扦插繁殖技术及生根过程中相关氧化酶[氧化物酶(POD),吲哚乙酸氧化酶(IAAO),多酚氧化酶(PPO)]活性,可溶性糖、可溶性蛋白、淀粉质量分数的动态变化。结果表明:山木通属于皮部生根类型,不同外源植物生长调节物质及质量浓度、浸泡时间和扦插基质4个因素对山木通插穗生根的影响均达到极显著水平(P<0.01),以河沙扦插基质,100 mg·L^(-1)吲哚丁酸(IBA)浸泡2 h处理的山木通扦插的生根质量最佳,生根率达21.67%。生根过程中,可溶性糖质量分数在不定根诱导期和根系生长期下降,根系表达期和生长后期糖质量分数有所回升;淀粉质量分数持续下降;可溶性蛋白质量分数在扦插后逐渐下降,插穗大量生根期达到谷值,然后又逐渐上升。插穗内POD,PPO,IAAO活性的变化均呈现"上升—下降"的趋势,在不定根表达初期达到峰值。经IBA处理的插穗营养物质质量分数变化幅度较对照组显著,且酶活性到达峰值时间较对照组早10 d,说明外源生长调节物质能够提高营养物质的利用率和氧化酶活性。

To study cutting propagation techniques with one-year-old cuttings of C lematis finetiana and to investigate the dynamic changes in activity of related oxidative enzymes [peroxidase（POD）,indoleacetic acid oxidase（IAAO）,and polyphenol oxidase（PPO）] as well as the content of soluble sugar,soluble protein,and starch,an L_9（3~4） orthogonal experiment was conducted with four treatments of exogenous hormones,hormone concentration,soaking time,and cutting matrix.Results indicated that rooting of C.finetiana was derived from the cortex.The effects of different exogenous hormones,hormone concentration,soaking time,and cutting matrix on rooting were notable by variance analysis.The best rooting formula was as follows：a matrix of river sand processed with Indole-3-butyric acid（1H-Indole-3-butanoic acid（IBA） 100 mg·L^-1 for 2 h producing a rooting rate of 22.7%.In the rooting process,the content of soluble sugar increased during the induction and root growth periods,but decreased during the expression period and the late growth stage.Soluble protein content decreased gradually after cutting reaching a low point when most cuttings rooted.Starch content declined throughout the process.Also,the POD,IAAO,and PPO activities all increased first and then decreased reaching a peak in the early stages of expression.Additionally,greater nutrient content for the test group was found than the control,and peak oxidase activities of test groups arrived 10 d earlier than the control.This demonstrated that exogenous hormones could improve the nutrient utilization and oxidase activities of cuttings.