白花延龄草种胚后熟休眠机理的研究

Research on Post maturation Mechanism of the Embryo of Trillium camschatcense

本文对白花延龄草新鲜种子和层积两年的白花延龄草种子进行变温处理,25/15℃条件下不同浓度的赤霉酸处理,利用智能光照培养箱(5/1℃、15/6℃、20/10℃、25/15℃、30/15℃)控制发芽温度,测定对比胚生长和发芽百分率同时进行根茎繁殖实验,研究其种胚后熟机制和根茎繁育特性。结果表明,白花延龄草新鲜种子无论在变温还是不同赤霉酸处理下均不发芽,层积两年后的种子在25/15℃条件下,变温25/15℃条件下,种胚在42天达到极限长度(0.68±0.083 mm),发芽率达到85±1%。在赤霉酸浓度为100 mg/L和200 mg/L处理下,球形的种胚在42天达到极限长度(0.68±0.083 mm),在浓度300 mg/L处理下,种胚生长迅速,56天达到极限长度(0.68±0.12 mm),发芽率达到最高为89±3%。层积两年的种子发芽百分率显著高于新鲜种子发芽百分率,即白花延龄草种子需采用冷层积和温度层积交替处理两年,完成形态后熟和生理后熟方可萌芽。另外,两年生根茎具有很强的生命活力,经过冬季漫长的休眠期,春季可发芽继续生长,即使将根茎种植在温室里,也不会缩短生长期而发芽。

This study investigates the post-ripening mechanism of seed embryos and rhizome propagation characteristics of Trillium camschatcense by subjecting fresh seeds and two-year stratified seeds to temperature fluctuation treatment and gibberellic acid(GA3)treatment at different concentrations under 25/15℃conditions.The germination temperature was controlled using an intelligent light incubator(5/1℃,15/6℃,20/10℃,25/15℃,30/15℃),and the embryo growth and germination percentage were measured and compared.Additionally,rhizome propagation experiments were conducted.The results showed that the fresh seeds of Trillium tschonoskii did not germinate under either temperature fluctuation or different GA3 treatments.For the two-year stratified seeds,the embryo reached its maximum length(0.68±0.083 mm)and a germination rate of 85±1%at 42 days under the temperature fluctuation condition of 25/15℃.When treated with GA3 at concentrations of 100 mg/L and 200 mg/L,the spherical embryos also reached their maximum length(0.68±0.083 mm)at 42 days.However,under a GA3 concentration of 300 mg/L,the embryo grew rapidly,reaching its maximum length(0.68±0.12 mm)at 56 days,with the highest germination rate of 89±3%.The germination percentage of two-year stratified seeds was significantly higher than that of fresh seeds,indicating that the seeds of Trillium tschonoskii require alternating cold stratification and temperature stratification for two years to complete morphological and physiological post-ripening before germination.Furthermore,the two-year-old rhizomes exhibited strong vitality,able to germinate and continue growing in spring after a long dormant winter period.Even when planted in a greenhouse,the rhizomes did not shorten their growth period or germinate prematurely.