【作者】 唐兰；

【导师】 何平；

【作者基本信息】 西南大学 ， 植物学， 2006， 硕士

【摘要】 金荞麦(Fagopyrum dibotrys(D.Don)Hara)隶属寥科荞麦属,是一种多年生草本植物,为国家重点二级保护野生植物,有极大的药用价值,主要产在我国西南、华中、华南等地,生于海拔250-3200m的山谷湿地、山坡灌丛。本文将野生金荞麦移栽于模拟酸雨、盐碱和干旱三种逆境下,对其生理生化指标变化、形态指标变化、开花物候以及根茎药用成分变化进行了初步研究,旨在探讨金荞麦在不同逆境下的生理适应性以及逆境对其根茎药用成分的影响,为其合理开发利用提供科学依据。结果如下: 1)模拟酸雨处理下,单因素方差分析表明4种不同处理的生理生化指标在短期内差异不明显。POD为恢复前的主要膜保护酶,SOD则为恢复后的主要膜保护酶。后期的主要功能是繁殖和药用成分的积累,光合作用有所减弱。形态指标中叶片数、基径和第一叶长宽比差异显著,叶片受酸雨的影响较大,因酸雨直接洒在叶片和植株上,所以引起叶片脱落。植株的叶片数、幼芽数和基径受到了一定影响,但在恢复后基本能够正常生长;主茎长、主茎节数以及叶片的长宽比都没有受到太大影响。表明金荞麦已经基本适应了一定酸雨环境,不同处理植株之间没有明显的胁迫反应。 2)盐碱处理下,单因素方差分析表明4种不同处理的生理生化指标在短期内的差异不明显。处理周期的主要膜保护酶仍然是POD,恢复周期内则是SOD。高浓度的盐碱胁迫对金荞麦的生理功能有较大的影响,恢复周期时其体内仍然含有较多的有害毒素过氧化氢,叶片逐渐调亡,同时光合作用受到了一定影响。形态指标中基径和第三叶长宽比差异达到了显著水平。较低浓度的盐碱对其影响较更多还原

【Abstract】 Fagopyrum dibotrys (D.Don) Hara, a perennial herb of Fagopyrum Mill, in Polygonaceae, is recorded as the National Important Wild Conservative Plants in China. Its root contains many useful medicinal components. In this paper, we studied on physiological and morphological adaptations, the flowering phenology as well as and root medicinal components of Fagopyrum dibotrys under simulated stress conditions with acid rain, alkaline-salt and drought. We further put forward some suggestion for the conservation and exploiting of the species. The results show as followings:1) The one-way ANOVA shows that the differences of physiological characters of Fagopyrum dibotrys among 4 different simulated conditions with acid rain are not significant within short time. POD is the main membrane conservation enzyme before restoration, and SOD is that after restoration. The main function of the species is propagating and accumulating medicinal components during late period, and photosynthesis becomes weaker. The influences of acid rain on leaves number, basal stem diameter and 1 st-leaf length/width are significant. Because of the acid rain on the leaves, the leaves are easily falling off. Leaves number, young bud and basal stem diameter are affected by acid rain slightly, but they can grow normally after restoration. Caulis length, caulis node number and leaves length/width are not affected by acid rain. It shows that Fagopyrum dibotrys has strong capacity of adaptation to the simulated conditions with acid rain.2) The one-way ANOVA further shows that the differences of physiological characters of Fagopyrum dibotrys among 4 different alkaline-salt conditions are not notable within short time. POD is the main membrane conservation enzyme before restoration, and SOD is that after restoration. Fagopyrum dibotrys still contain many hydrogen peroxide, leaves become dying, and its photosynthesis is also affected duringrestore period. The differences of basal stem diameter and 3rd-leaf length/width are significant. Low concentration alkaline-salt conditions can’t affect it greatly, but high concentration alkaline-salt conditions (higher than 0.5%) can affect it greatly and causing dying of the plants. It shows that Fagopyrum dibotrys can’t adapt to the alkaline-salt conditions, especially high alkaline-salt conditions.3) The differences of SOD activity are significant before restoration. The function of SOD activity and POD activity is reciprocal. The plants become dry, and their photosynthesis function has been affected greatly under drought conditions. The differences of caulis length, 2nd-leaf length/width and 3rd-leaf length/width are significant mostly before restoration. Leaves number, young bud and basal stem diameter are affected, but caulis length and caulis node number are not affected. It shows that Fagopyrum dibotrys has certain capacity of adaptation to the drought conditions in short time.4) During the whole experiment period there are two flowering periods, i.e., the first ten days of June and from the last ten days of September to the first ten days of November. It shows that the flowering period of Fagopyrum dibotrys change ahead to June under the simulated stress conditions. The energy supplies for flowering has been spent partly ahead of the normal flowering period, while it can’t blossom completely comparing with the normal conditions during the 2nd flowering period. The differences of flowering phenology is significant under simulated conditions,. Though Fagopyrum dibotrys can blossom more or less normally under the simulated conditions with acid rain, it doesn’t blossom under higher concentration of alkaline-salt conditions. The differences of flowering phenology are not significant under the drought conditions. Short flowering time and higher mean flowering amplitude can guarantee the success of flowering of Fagopyrum dibotrys under the normal conditions.5) Low concentration of acid rain can seemingly accelerate the accumulation of the root medicinal components, which reveals that the Fagopyrum dibotrys has certain capacity of adaptation to the simulated conditions with acid rain. The differences of root medicinal components are significant under alkaline-salt conditions. High concentration of alkaline-salt can cause many soluble sugars storage in plants. Then those soluble sugars become medicinal components after restoration. But the total medicinal components content is not high. In terms of the contents of the total medicinalcomponents, alkaline-salt condition is not good for accumulating root medicinal components. Lower concentration of PEG can accelerate accumulating of root medicinal components under drought conditions, while higher concentration of PEG is not good for the accumulation of root medicinal component.6) Following procedures should be taken into consideration when conservation of this species is taken. Firstly, pay more attention to conserve medicinal plants resource and control excavating of Fagopyrum dibotrys. Secondly, consider the factors including acid rain, alkaline-salt, drought and so on, when ex-situs conservation of this species is taken. Thirdly, set up Fagopyrum dibotrys miniature conservation area.更多还原