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1.
本文收集了近年来70种豆科植物种子形态学和消化道作用后萌发行为数据,利用植物亲缘系谱和整合分析,以阐明豆科植物种子经过草食动物消化道作用后萌发行为的变化。结果表明,豆科植物种子经过消化后,萌发率受到抑制(OR=0.89),但抑制效应和促进效应差异不显著(OR95%=0.61~1.28,P0.05);以亲缘关系为依据将70种豆科植物分为7个类群,其中消化作用对金合欢属、含羞草属、银合欢属、牧豆树属和角豆树属的第1类群种子萌发有显著的促进效应;而对包括木豆属、毛蔓豆属、爪哇大豆属、扁豆属、胡枝子属和距瓣豆属的第4类群有显著的抑制效应。将第3、5类群再划分成3个亚组进一步分析,结果表明,消化作用对苜蓿属种子萌发有显著促进,笔花豆属则受到显著抑制,三叶草属种子的抑制和促进效应之间差异不显著。车轴草族25种植物种子表现出质量中等种子经消化后萌发率显著提高,而过小或过大的种子经消化道作用后萌发率受到明显抑制。其他45种植物的种子重量与消化后的萌发效应存在不显著的负相关关系(R2=0.035,P0.05)。  相似文献   

2.
在实验室条件下研究了青藏高原东缘11种小檗属(Berberis)植物的种子萌发特性,并分析了种子萌发能力与种子大小和海拔之间的关系。结果表明,11种植物中,仅有5种植物(金花小檗、匙叶小檗、锥花小檗、鲜黄小檗和刺黄花)种子萌发率超过50%,其中金花小檗最高(86.7%);有2种植物(巴东小檗、华西小檗)种子始终没有萌发,其余4种植物种子萌发率均在10%以下;种子萌发开始时间均在10d以后,匙叶小檗种子萌发的持续时间最长(40d)。11种植物种子萌发率、萌发速率、萌发持续时间与种子大小均呈显著负相关,而萌发开始时间与种子大小之间具有显著的正相关关系。萌发率、萌发速率、萌发持续时间与海拔均有较弱的正关联,萌发开始时间与海拔有较弱的负关联。  相似文献   

3.
以3种肉苁蓉属(Cistanche)植物种子为材料, 研究了氟啶酮对肉苁蓉种子萌发和吸器发育的影响。结果表明: 氟啶酮处理10天后种子开始萌发, 然后, 胚根顶端膨大, 发育出吸器。管花肉苁蓉种子萌发率最高, 达到82%; 盐生肉苁蓉吸器诱导率最高, 达到52%; 对照处理的种子不萌发。这说明氟啶酮是有效刺激肉苁蓉种子萌发和吸器发育的信号物质。  相似文献   

4.
运用一种实验装置往往可以探究多个问题,而与萌发种子呼吸相关的问题也屡见不鲜.通过一种常见的实验装置对萌发种子呼吸中几个典型的问题进行了探究,分别从萌发种子呼吸作用的类型、种子萌发时的耗氧量以及萌发种子的呼吸商等3个方面阐述了其在探究萌发种子呼吸中的应用.  相似文献   

5.
猕猴桃属植物生物学特征特性观测   总被引:11,自引:2,他引:9       下载免费PDF全文
李瑞高  梁木源  李洁维  毛世忠   《广西植物》1996,16(3):265-272
观测了猕猴桃属41个种或变种、变型及2个种间杂交后代的幼苗、成年植株、花器、果实及种子等的植物学特征及物候期、开花结果习性等生物学特性,为该属植物的系统发育、杂交育种选择亲本、定向培育以及制定相应的栽培技术措施等研究提供了科学依据.  相似文献   

6.
26种树木种子的需光萌发特性,可归结为下列几种类型:(1)一次性感光萌发。如泡桐、木庥黄、四薮木和白千层等种子。(2)光周期性诱导萌发。如团花、八宝树、散沫花、文丁果、榕属、香果树和杜鹃等种子。(3)光促进萌发。如光叶天料木,桑树、赤杨、柏木、桉树属和紫薇等种子。  相似文献   

7.
5种野生无髯鸢尾种子休眠与萌发特性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
以5种野生无髯鸢尾种子为材料,从种子的吸水率和发芽率两个方面分析休眠原因与打破休眠促进萌发的方法,为中国鸢尾属植物的种质资源保护与应用提供技术支持。结果表明:(1)5种野生无髯鸢尾种子的吸水率比较显示,玉蝉花和山鸢尾的种皮透水性最好,其次是燕子花的种皮透水性,溪荪的种皮透水性最差;种皮的透水、透气性差及致密的胚乳是抑制马蔺种子萌发的主要原因;另外,变温可增加野生无髯鸢尾种子种皮和胚乳的透水性。(2)马蔺和溪荪种子的种皮对萌发存在强烈的抑制作用,而燕子花、山鸢尾和玉蝉花种子的种皮抑制作用不显著;珠孔端胚乳是5种野生鸢尾种子休眠的主要因素。(3)温度对5种野生无髯鸢尾种子萌发影响很大,变温处理显著提高了马蔺、溪荪、玉蝉花种子的萌发率,且最适条件为:变温30℃/20℃、8h光照/16h黑暗,但该条件对山鸢尾和燕子花种子萌发的影响不显著,即单一因子不能打破燕子花和山鸢尾种子的休眠。研究发现,5种野生无髯鸢尾种子休眠和萌发特征各异,主要影响因素也不尽相同,但珠孔端胚乳是5种野生无髯鸢尾种子休眠的主要因素;低温层积处理与变温30℃/20℃相结合能明显提高野生无髯鸢尾属种子的发芽率,是其种子打破休眠的有效措施。  相似文献   

8.
野生花卉大百合属植物繁殖技术研究进展   总被引:2,自引:0,他引:2  
大百合属(Cardiocrinum)植物是一类具有重要应用价值的野生花卉,对其繁殖技术体系的研究旨为推广应用奠定基础。从引种栽培、种子生理、组织培养等方面综述了大百合属繁殖技术的研究进展,认为利用种子和组培进行大量繁殖已成为可能,对其杂交育种还需进一步深入研究,今后也应对其进行现代生物技术的应用研究。  相似文献   

9.
某些兰科植物的种子成熟前,在无菌萌发过程中有较高的萌发率,而成熟后萌发率急剧下降。本研究针对这一现象,对三种兜兰属植物种子的发育过程进行了解剖学观察,并对授粉后不同时期的种子进行无菌播种,80d后统计其萌发率,以探究种子发育过程中的解剖学特征与萌发率之间的关系。研究结果表明种胚刚发育到椭球形胚的时候,胚柄尚存,种皮细胞尚未皱缩,此时三种兜兰的萌发率都能达到较高水平,表明这是适合兜兰属植物萌发的最佳时期;此后,种皮开始皱缩,木质素类物质积累导致种皮透水性下降,推测这可能是导致其后期萌发率下降的主要因素之一。  相似文献   

10.
一种刺激肉苁蓉种子萌发和吸器发育的方法   总被引:7,自引:1,他引:6  
以3种肉苁蓉属(Cistanche)植物种子为材料,研究了氟啶酮对肉苁蓉种子萌发和吸器发育的影响。结果表明:氟啶酮处理10天后种子开始萌发,然后,胚根顶端膨大,发育出吸器。管花肉苁蓉种子萌发率最高,达到82%;盐生肉苁蓉吸器诱导率最高,达到52%;对照处理的种子不萌发。这说明氟啶酮是有效刺激肉苁蓉种子萌发和吸器发育的信号物质。  相似文献   

11.
黄檗的更新特点及食果实鸟类对其种子的传播   总被引:20,自引:5,他引:15  
在帽儿山实验林场和哈尔滨实验林场 ,黄檗母树下没有幼苗分布 ,不能进行天然更新 ,需要靠食果实鸟类等将果实和种子传播至远离母树的其他林下。捕食黄檗果实的食果实鸟类有 9种。其中 6种是食果肉鸟类 ,吞入果实后 ,消化果肉 ,而种子完整地随粪便排出而得以传播。其余 3种是食种子鸟类 ,没有传播作用。果实在鸟类消化道内的滞留时间达 2 0~ 30min ,具有很长的潜在传播距离。将鸟类消化后的种子与完整果实和人为去果肉种子进行萌发对比实验 ,消化后种子的累计萌发率与其余二者之间均没有显著性差异 ,说明食果实鸟类的消化 (道 )过程对种子萌发没有明显影响 ,同时证明果肉对种子萌发率没有显著影响 ,果肉中不含萌发抑制物质。黄檗提供多种鸟类以食物 ,而鸟类也同时以多种肉质果植物为食物。因此食果实鸟类和肉质果植物 (包括黄檗 )之间形成了松散的互利共生关系  相似文献   

12.
温度是影响种子萌发的重要的环境因素之一。该文以青藏高原东缘的12种菊科植物为研究对象, 结合Logistic函数和积温公式, 通过非线性回归方法估算种子萌发的最低温度和积温, 研究了种子萌发对不同温度的响应。研究结果表明: (1)青藏高原东缘的12种菊科植物种子萌发的最低温度的平均值为0 ℃, 积温的平均值为94.5 ℃·d。与前人的研究相比, 该研究中萌发的最低温度较低, 积温较高, 这是该区域菊科植物长期适应青藏高原特殊的温度环境的结果; (2)种子萌发的最低温度与积温之间存在着显著的负相关关系(p = 0.04)。萌发最低温度较低的物种积温较高, 避免了种子在多变的温度环境下较早萌发所遇到的风险; (3)种子大小与积温之间存在着显著的正相关关系(p = 0.01)。在萌发最低温度差别不大的情况下, 与大种子相比, 小种子萌发所需的积温较低, 萌发较快, 在群落演替的早期占有优势。  相似文献   

13.
Worldwide, there is relatively little information on seed dormancy and germination of tropical montane species. Our aim was to help fill this knowledge gap by conducting seed dormancy/germination studies on woody species from this vegetation zone in Hawai`i. All species had water-permeable seeds with a fully developed embryo. Seeds of 29 species (23 genera) were incubated in light/dark at 15/6, 20/10 and 25/15°C and germination monitored at 2-week intervals for 16–128 weeks. Seeds of Chenopodium oahuense, Dubautia menziesii and Silene lanceolata were non-dormant (ND) and those of 26 other species had physiological dormancy (PD); 10 of the 26 species had conditional PD. The optimum germination temperature regime(s) was (were) 25/15°C, 17 species; 25/10 and 20/10°C, 2; 20/10°C, 6; 20/10 and 15/6°C, 2; and 15/6°C, 2. Worldwide, PD in the woody genera included in our study is more common than ND. In addition to its contribution to the world biogeography of seed dormancy/germination, this study will be useful to conservation biologists who need to germinate seeds of tropical montane species.  相似文献   

14.
Exposure of dormant seed to cold smoke derived from burnt native vegetation had a positive influence on germination in one or more seed provenances in 45 out of 94 species of native Western Australian plants that are normally hard to germinate. When tested under controlled conditions some species showed earlier germination in smoke treatments than controls; in others smoke-treated seeds continued to germinate for several weeks after controls had achieved full germination. In the remainder, treated and control seeds germinated to similar time schedules. A group of 23 species which responded positively had previously been recorded as extremely difficult or impossible to germinate using conventional techniques. These included members of the genera Geleznowia (Rutaceae), Hibbertia (Dilleniaceae), Stirlingia (Proteaceae), Verticordia (Myrtaceae), Actinostrobus (Cupressaceae) and Pimelea (Thymelaeaceae). Both large- and small-seeded species were encountered amongst the positively responding taxa, which encompassed representatives of 15 families and 26 genera of dicotyledons, 5 families and 8 genera of monocotyledons and the gymnosperm Actinostrobus acuminatus. Sowing seeds on smoke-fumigated filter papers or watering with aqueous eluates of smoke elicited similar degrees of stimulation of germination, as did exposure to gaseous smoke in a readily germinating species Anigozanthos manglesii (Haemodoraceae) and the normally intractable species Lysinema ciliatum (Epacridaceae). Exposing recently burnt and unburnt natural bushland sites to smoke, smoked water or smoked dry sand elicited a significant germination response in 15 species. Over one third of the species sampled in the burnt site exhibited germination additional to that caused by the fire. Data are discussed in relation to previous germination studies on Australian and other taxa.  相似文献   

15.
The seed size and number theories have been proposed to explain the advantages of having many small versus a few large seeds in plants. In particular, seed germination is predicted to be shaped by temperature, and may differ for small and large seeds. In this study, we experimentally test germination at different temperatures in 12 species of arid zone plants in the genus Frankenia L. that differ in seed mass. Seed mass was categorized as “smaller-seeded species” versus “larger-seeded species” for analysis (six species per category). Many of these species co-occur geographically and hence experience similar abiotic conditions (unpredictable rainfall, extremes in temperature, poor soil conditions). The results demonstrated differences in germination as a result of the temperature*seed mass(species) interaction effect. There were significant differences in germination rates across seed mass categories during the first eight days of germination. Germination rates were higher in the larger-seeded species than the smaller-seeded species. Smaller-seeded species had lower germination success but had higher germination rates at lower temperatures, and had a more stringent temperature as a germination cue. These findings are discussed in the context of life-history strategies in arid zone plants.  相似文献   

16.
Summary The establishment of direct seeded revegetation is well researched. However, there is little understanding of whether revegetation simplifies with age and loses many of the short‐lived understorey shrub species that provide critical resources for birds and other fauna, or regenerates sufficiently to be self‐sustaining. We sought to address this by investigating the change in structure and composition of 33 direct seeded sites established by Greening Australia between 1990 and 1996 in the Southern Tablelands of NSW. Transects were used to collect data describing the abundance and richness of woody plants in 1998 and 2008, and the abundance of woody plant regeneration in 2008. Our analysis showed the predicted number of live stems per metre declined exponentially from 5.8 stems/m (~17 000 stems/ha) at age 1.5 years to 1.5 stems/m (~4500 stems/ha) at age 17.5 years. Predicted woody plant species richness also declined with age, with a linear relationship. The number of species in the seed mix affected predicted woody plant species richness. However, large increases in seed mix richness produced relatively small increases in predicted species richness. Regeneration (new stems) was present at high levels (>100 stems/ha); however, 82% of regeneration appeared to originate from delayed germination of sown seed rather than seed from established plants (recruitment). The predicted abundance of new stems (delayed germination and recruitment) declined with age, and for a given age increased with row width. Young stands (11.5 years), seeded with wide rows (4 m), had approximately six times the new stems of similar aged stands seeded with narrow rows (2 m). Our results indicate direct seeded stands simplify with age, becoming less dense and containing fewer species. Maintaining a diversity of shrub species in direct seeded sites may therefore require ongoing disturbances (scarifying, scalping, fire, thinning) of established sites and changes to establishment techniques for new sites. We suggest further research to establish the status of soil seed banks in direct seeded sites, testing different forms of disturbances to trigger regeneration in older revegetation sites and establishing new sites using wide rather than narrow rows and seed mixes enriched with species from genera other than Eucalyptus or Acacia.  相似文献   

17.
Germination in 35 species from 15 legume genera of southeastern Australia was promoted by a heat treatment which broke the seed coatcaused dormancy. Once the critical temperature was reached, most seeds had their dormancy broken, independent of the duration of heating. Species fell into three classes according to whether their dormancy was broken by a temperature of 40, 60 or 80°C. Highest germination in all species was achieved by heating in the temperature range 80–100°C, although long durations (120 min) at 100°C caused seed death in several species. At 120°C, seeds of most species were killed at all but one minute's duration. A proportion of seeds from 7 species (Acacia myrtifolia, Pultenaea daphnoides, P. incurvata, P. linophylla, P. polifolia, Dillwynia floribunda and Sphaerolobium vimineurn) was not killed at 120°C and had their dormancy broken. This proportion varied markedly and resultant germination levels were significantly less than those at 80 and 100°C, except in S. vimineum. Between-site variations in the 4 species tested (A. myrtifolia, A. suaveolens, A. terminalis and A. ulicifolia) were small. These variations concerned: (i) the minimum temperature required to break seed dormancy in 2 species: 60°C in one population of A. myrtifolia and A. suaveolens, and 80°C in the other; and (ii) the intensity of the germination response. Duration of heating was less important than temperature as a determinant of germination. Ordination techniques revealed that results from one duration across temperatures were comparable with data from multiple durations. This has significant applications in studying rare species, where seed may be in short supply. Predicted germination levels after a moderate intensity fire should far exceed those after a low intensity fire. Little germination was predicted for many species after a low intensity fire and for one species, A. elongata, no germination was predicted. The potential role of indicator species in relation to the maintenance of species in a community is suggested.  相似文献   

18.
The mode of germination of representatives of 89 genera of the Cactaceae, 4 genera of Portulacaceae and 1 genus of Phytolaccaceae was studied. Most of the species of the Cactaceae germinate by means of a seed lid (operculum). In the Cactaceae studied 11 kinds of germination could be distinguished, 3 of which were with, and 8 without, operculum formation.
Opercula are restricted in their occurrence to the subfamilies Cactoideae (Cereoideae) and Pereskioideae and are not found in the subfamily Opuntioideae. Within the subfamily Cactoideae operculum formation was found to occur in all tribes and in all investigated subtribes. Opercula were also found in two genera of the related family of the Portulacaceae. In the Phytolaccaceae no operculum formation was observed.  相似文献   

19.
蚌湖湖滨带的土壤种子库特征   总被引:1,自引:0,他引:1  
采用幼苗萌发法,在湿润和淹水两种水位萌发条件下,研究了蚌湖(鄱阳湖子湖)湖滨带5个水位梯度区的土壤种子库特征。结果表明,种子库中共萌发了33个物种,分属15科29属。物种组成以一年生草本为主,其中莎草科、禾本科、菊科、玄参科和水鳖科的物种数最多。不同水位区种子库的物种组成和幼苗密度差异不显著。种子库在两种水位条件下萌发的结果有显著差异,湿润条件下种子库萌发的物种以湿生和挺水植物为主,而在淹水条件下萌发的沉水植物种类和幼苗数量显著增多,其幼苗密度占总幼苗数的36%。t检验表明种子库在淹水条件下每个萌发盒中萌发的物种数(7.2±2.8)显著多于湿润条件(4.2±2.0)。  相似文献   

20.

Background and Aims

Sapindaceae is one of 16 angiosperm families whose seeds have physical dormancy (PY). However, the extent and nature of PY within this family is poorly known. The primary aims of this study were: (1) to evaluate seed characteristics and determine presence (or not) of PY within nine genera of Australian Sapindaceae; and (2) to compare the frequency of PY across the phylogenetic tree within Australian Sapindaceae.

Methods

Viability, imbibition and seed characteristics were assessed for 14 taxa from nine genera of Sapindaceae. For five species of Dodonaea, optimal conditions for germination and dormancy break were evaluated. An in situ burial experiment was performed on D. hackettiana seeds to identify the factor(s) responsible for overcoming PY. Classes of dormancy and of non-dormancy for 26 genera of Sapindaceae were mapped onto a phylogenetic tree for the family.

Key Results

Mean seed viability across all taxa was 69·7 %. Embryos were fully developed and folded (seven genera) or bent (two genera); no endosperm was present. Seeds of all five Dodonaea spp. and of Distichostemon hispidulus had PY. Hot-water treatment released PY in these six species. Optimal germination temperature for seeds of the four Dodonaea spp. that germinated was 15–20 °C. Following 5 months burial in soil, 36·4 % of D. hackettiana seeds had lost PY and germinated by the beginning of the winter wet season (May). Laboratory and field data indicate that dormancy was broken by warm, moist temperatures (≥50 °C) during summer.

Conclusions

PY occurs infrequently in genera of Sapindaceae native to Australia. Seeds of Dodonaea and Distichostemon had PY, whereas those of the other seven genera did not. Seeds of these two genera and of Diplopeltis (a previous study) are the only three of the 20 native Australian genera of Sapindaceae for which germination has been studied that have PY; all three belong to subfamily Dodonaeoideae.Key words: Dodonaea spp., physical dormancy, Sapindaceae, seed ecology, seed germination  相似文献   

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