青藏高原的兰科植物

一、兰科植物在青藏高原的种子植物中是大科之一,共有99属,474种及9变种.属占我国国产属总数的61.5%,地生型54属,附生型37属,腐生型8属.种数占我国国产种总数的46.5%,属中含超过20种的属有:虾脊兰属、羊耳蒜属、杓兰属、舌唇兰属、玉凤花属和石豆兰属,含10-20种的属有石斛属、毛兰属、角盘兰属、无柱兰属、阔蕊兰属、红门兰属、贝母兰属和对叶兰属,而仅含1种的属有43属,含2种的属有15属.兰科植物在本地区的分布是以横断山     

茂兰的兰花

茂兰,顾名思义,到处生长着茂盛的兰花。位于黔桂交界的茂兰,有优越的水热条件、良好的森林植被,加之独特的喀斯特地表生境,为兰花的生长提供了十分有利的条件。因而这里的兰花种类丰富、类型繁多。据调查,茂兰现有野生兰科植物32属85种。 在茂兰,既有广布我国的兰属的一些种类,即我们常说的兰花,如春兰、蕙兰、多花兰、兔耳兰、建兰等地生兰花;也有常附生在岩石表面、树枝上的附生兰种类,如石槲、羊耳蒜、石仙桃、隔距兰等;既有属于热带的附生兰花,如多花脆兰、鸢尾兰、万带兰、馥兰等;还有常分布于温带的一些种类,如杜鹃兰、白芨、珊瑚兰、对叶兰、角盘兰等。 走进茂兰,你就会为茂兰兰花的繁多所惊叹。在浓荫蔽日、阴暗潮湿的漏斗洼地里,生长着端庄秀丽的虾脊兰、花大艳人     

中国西藏兰科植物新资料

中国西藏东南地区位于东喜马拉雅和印缅的交接处,是全球生物多样性的热点地区,尤其是位于该地区的墨脱,由于巨大的海拔高差,使该地区的植被类型呈显著的垂直地带性,且植物种类繁多、植被结构复杂。该文报道了西藏野生兰科植物新记录属3个,即线柱兰属(Zeuxine)、爬兰属(Herpysma)和槽舌兰属(Holcoglossum);新记录种27个,即白肋线柱兰(Zeuxine goodyeroides)、爬兰(Herpysma longicaulis)、小花槽舌兰(Holcoglossum himalaicum)、西南齿唇兰(Anoectochilus elwesii)、窄唇蜘蛛兰(Arachnis labrosa)、短足石豆兰(Bulbophyllum stenobulbon)、尖角卷瓣兰(B. forrestii)、南方虾脊兰(Calanthe lyroglossa)、泰国牛角兰(Ceratostylis siamensis)、金唇兰(Chrysoglossum ornatum)、格力贝母兰(Coelogyne griffithii)、云南贝母兰(C. assamica)、斑舌兰(Cymbidium tigrinum)、梳唇石斛(Dendrobium strongylanthum)、狭叶金石斛((D. angustifolium)、厚唇兰(D. mariae)、粗茎苹兰(Pinalia amica)、垂叶斑叶兰(Goodyera pendula)、绿花斑叶兰(G. viridiflora)、狭叶羊耳蒜(Liparis perpusilla)、小花羊耳蒜(L. platyrachis)、三裂羊耳蒜(L. mannii)、镰叶鸢尾兰(Oberonia falcata)、阔瓣鸢尾兰(O. latipetala)、凹唇石仙桃(Pholidota convallariae)、大苞兰(Sunipia scariosa)、滇南矮柱兰(Thelasis khasiana)。这些植物新资料的发现,对于丰富西藏植物种类以及对该地区物种多样性的保护和研究具有重要意义。     

西藏地区13种虾脊兰植物花部表型及花粉形态特征研究

该研究对西藏地区13种虾脊兰植物花部表型及花粉形态特征进行观察比较,目的为虾脊兰植物的分类鉴定和种间亲缘关系的确定提供新依据。研究结果显示:①13种虾脊兰在花颜色大致可分为黄色、黄绿色、黄褐色、粉红色4种,以粉红色的花居多;②13种虾脊兰均为总状花序,花各部位(萼片、花瓣、唇瓣、子房、柱头)的长、宽度测量指标均表现出不同程度的差异,萼片长、花瓣宽、唇瓣宽和柱头长4个测量指标的差异性最大,在各个种之间的P值结果表现出显著性差异水平;③这13种虾脊兰的花粉块均由成千上万个单粒花粉组成,未见到萌发孔结构,有些虾脊兰植物的花粉粒之间可以看到有明显黏结物质。花粉块大小不一,整体形状多呈卵圆形、长椭圆形和梨形;④不同种的虾脊兰花粉块表面形态特征有所差异,花粉粒纵向或横向排列堆积在一起,花粉粒形状也各不相同;⑤不同种虾脊兰的花粉粒表面纹饰特征区别明显,可划分为凹陷型、光滑型、小孔型和穿孔型。以上结果表明花部表型及花粉形态特征可作为13种虾脊兰植物分类鉴定的参考性状,对这13种虾脊兰植物亲缘关系的确定和系统分类有补充价值。     

几种兰花种子无菌萌发及胚胎发育过程的几种途径

以虎头兰(黄色素花)×大雪兰、大雪兰×虎头兰(黄色素花)、虎头兰(黄色素花)×黄蝉兰、黄蝉兰×虎头兰(黄色素花)、冬凤兰、竹叶兰、窄唇蜘蛛兰、半柱毛兰、三褶虾脊兰和多花脆兰为材料,进行了杂交和自交种子无菌培养研究,并对胚胎发育进行了显微观察,结果表明:兰花种胚的发育途径有两条,一是种胚突破种皮后再转绿;二是种胚转绿后再突破种皮,且两条途径是同时进行的。种胚突破种皮的方式有3种:一是种子发育过程中,种皮慢慢消失,变成裸露的胚;二是种胚向种子的一端移动,最终突破种皮;三是种胚从种子的一侧突破种皮,形成裸胚。幼苗的发育途径有两条:一是小球体经圆球茎发育成小苗;二是小球体伸长成根茎后发育成小苗。     

贵州兰科植物的新记录

报道了贵州兰科的3个新记录属:羽唇兰属、坛花兰属、异型兰属;以及9个新记录种:羽唇兰、坛花兰、异型兰、等萼卷瓣兰、广西舌喙兰、广西鸢尾兰、勐海隔距兰、长足石仙桃、长距虾脊兰。凭证标本保存在茂兰保护区标本室(HML)。     

铁皮石斛不同授粉方式对蒴果发育及种子萌发的影响

为研究不同授粉方式对铁皮石斛蒴果发育以及无菌播种种子萌发的影响,选用健康的铁皮石斛植株花朵进行了自花授粉、异花授粉和自然授粉;选用不同种龄的种子在离体培养条件下进行萌发实验。研究结果表明:铁皮石斛自花授粉和异花授粉均能结实,异花授粉的结实率较高,达64.8%;铁皮石斛在开花的第2~3天授粉的结实率最高;120~210 d种龄的种子萌发率较高,均为90%以上。选择人工异花授粉和适宜种龄的种子离体培养,不仅可培育优良品种,还可缩短繁殖周期,为铁皮石斛遗传改良提供依据。     

无距虾脊兰花粉离体萌发及储藏条件的研究

以天目山野生无距虾脊兰的花粉为材料,采用离体萌发法研究了花粉的储藏性以及不同的培养基组分和培养条件对花粉萌发和花粉管生长的影响,并采用联苯胺-过氧化氢法测定了其柱头的可授性,以筛选无距虾脊兰花粉的培养方法以及储藏条件,为其种质资源保存等研究奠定基础。结果表明:(1)无距虾脊兰最适花粉液体培养基为200g·L-1蔗糖+50mg·L-1 H3BO3+40mg·L-1 Ca(NO3)2·4H2O,并且在pH 5.5~6.0、温度25℃恒温下培养48h,无距虾脊兰花粉萌发率(81.71%)和花粉管生长(247.42μm)最佳。(2)无距虾脊兰花粉在-80℃中低温干燥储藏360d后仍具有48.58%的萌发率。(3)无距虾脊兰的柱头在开花前5d内均具有可授性,花粉块在整个花期内均保持了28.96%~81.71%的生活力,但柱头可授性和花粉活力均随开花后时间的延长显著降低。     

四种石斛兰种胚发育进程研究

以玫瑰石斛、尖刀唇石斛、短棒石斛、兜唇石斛种子为材料,进行种胚非共生萌发研究,并对其种子形态和胚的发育进程进行了显微观察。结果表明:处于球形胚阶段的石斛兰种子,种胚吸胀后突破种皮,发育至吸收毛和芽生长点出现后,种胚形成原球体;种子萌芽后胚尚未成熟,只进入心形胚阶段。呈纺锤形种子的种皮两端形状不同,一端存在结点,呈弯曲状的尖形,另一端种皮呈收拢的圆口形。4种石斛兰种子,玫瑰石斛种子最长,为两端狭长的纺锤形;兜唇石斛种子最短,呈两端稍细的纺锤形。玫瑰石斛、短棒石斛、尖刀唇石斛种子胚培养需要5～10 d萌发;兜唇石斛种子和胚皆偏小,萌发需要30 d。石斛兰种胚和种皮吸水膨胀后,种胚向种皮的一端移动、脱出或种胚撕裂种皮中央后突破而出,形成裸胚。玫瑰石斛种子撕裂种皮后主要从种皮中央突破;短棒石斛、尖刀唇石斛、兜唇石斛部分种胚从种皮一端脱出,部分种胚则从中央撑破种皮脱出。充分膨胀、变绿后萌芽的裸胚,存在极性,顶部芽生长点萌动,下部出现成群散射状吸收毛。     

铁皮石斛种子的室内共生萌发

由于人为的采挖和原生境的破坏,使得铁皮石斛野生资源已濒临灭绝。因此,保护铁皮石斛野生资源及其生境,加快其野生资源的繁殖显得非常重要。以铁皮石斛种子(TTC染色显示种子生活力为77.65%)为材料,与分离自2种野生兰科植物根部的4株共生真菌 (C20来自铁皮石斛,L12,L24b 和 L28来自美花石斛)在燕麦培养基上进行共生萌发。经过18周的共生培养,4株真菌均不同程度地促进了铁皮石斛种子的萌发,其中菌株L24b (Epulorhiza)和L28 (Epulorhiza)显著提高了种子的萌发率,分别比对照高出26.51%和12.20%,但未形成幼苗,只是处于原生分生组织阶段(阶段3);菌株C20(Epulorhiza)和L12 (Alternaria) 虽没有显著提高种子的萌发率,但对原球茎的发育和幼苗的生长有明显的促进作用;而对照的种子仍然处于膨大转绿期,即萌发阶段(阶段2)。同时发现,TTC染色显示的铁皮石斛种子生活力要高于种子共生萌发的萌发率(除了菌株L24b)。研究结果表明:种子生活力染色检测的活力值只代表种子所具有的潜在的萌发能力,而不能代表实际的萌发率。在异地条件下,铁皮石斛与共生真菌间没有严格的专一性,可以与瘤菌根菌属、链格孢属真菌形成共生关系。菌株C20和L12能促进萌发后的种子进一步分化成幼苗。这两个菌株为铁皮石斛的人工优质栽培和野外种群的建立提供了可能。     

贵州毕节喀斯特地区优势植物种子萌发特性初步研究

对采自贵州毕节地区的11种植物的种子萌发特性进行了初步研究,结果表明：①盐肤木、火棘、化香、云贵金丝桃与白栎种子在4周之内能够萌发;除云贵鹅耳枥胚坏死之外（萌发实验前后对种子进行解剖）,其他5种植物的种子都未萌发,处于不同的休眠状态。②盐肤木、化香、云贵金丝桃的种子光照时的萌发率远高于黑暗时的萌发率,具有显著差异,尤其是云贵金丝桃,因此3种植物种子均属于喜光性种子;而火棘与白栎种子有无光照都可以萌发,而且萌发率没显著差异,因此属于光不敏感或光中性种子。③盐肤木、云贵金丝桃的种子在30℃较高温条件下萌发最好;白栎、火棘种子在15℃、20℃低温条件下萌发更好;化香种子萌发温度既不能低于20℃也不能高于25℃。④刺异叶花椒种子吸水率高达85%,胚包埋在胚乳之中非常微小、未分化,因此可以初步判定属于形态休眠或者形态生理休眠;而平枝荀子、西域旌节花、云南旌节花种子吸水率都在20%以上,胚长/种子长都超多1/2,并且胚已发育完全,应属于生理休眠;小果蔷薇种子吸水率约27%,胚长/种子长都达2/3,并且通过对种子的解剖发现胚还未发育,应属于形态生理休眠。     

紫翅猪毛菜的种子多型性及其结实格局

紫翅猪毛菜(Salsola affinis)主要分布于新疆准噶尔荒漠, 具有很强的抗干旱和耐盐碱能力, 其种子具有多型现象。我们对紫翅猪毛菜的种子形态、萌发特性及结实格局进行了观测研究。结果表明: (1) 紫翅猪毛菜3种类型的种子在形状、大小、颜色、着生方式及包被其花被片背部是否具翅方面均有明显不同; (2) 3种类型的种子具有不同的散布特性和萌发行为: A型种子容易从母体脱落, 发达的果翅能够借助风进行远距离传播; B、C型种子成熟时紧连母体, 不易脱落。在变温下A型种子和B型种子能够快速萌发, 且B型种子比A型种子的萌发速度快; 而C型种子萌发缓慢, 最终萌发率小于10%, 表明其处于休眠状态; (3)随植株个体的增大, A型种子所占比例逐渐增多, 由0.43%增加到51.07%; B型种子所占比例逐渐减少, 由65.80%减少到18.06%; C型种子所占比例没有显著变化, 约为30–35%。紫翅猪毛菜的种子多型性以及种子输出的灵活性有利于其在荒漠异质环境中成功定居。对种子多型性及其结实格局的研究将为探讨其生态适应机制及生活史进化研究提供科学依据。     

散枝猪毛菜的种子多型性及其萌发行为

散枝猪毛菜(Salsola bracchita)主要分布于新疆准噶尔荒漠,具有很强的抗干旱和抗盐碱能力。该文对散枝猪毛菜的果实进行了观察,表明散枝猪毛菜具有4种类型的散布单位和果实,这4种果实在形状、大小、颜色和着生方式上均有显著差异。A型果实绿色、球形、大,着生方式为横生,宿存花被革质,背部有紫红色翅状附属物,直径为(2.161±0.138) mm,单粒重为(3.810±0.113) mg;B型果实绿色、大、扁平、长圆形,着生方式为直立,宿存花被革质,背部有翅状附属物,长为(2.062±0.188) mm,宽为(1.720±0.148) mm,单粒重为(2.665±0.113) mg;C型果实绿色、大、扁平、长圆形,着生方式为直立,宿存花被膜质,背部无翅状附属物,长为(2.239±0.277) mm,宽为(1.844±0.150) mm,单粒重为(2.723±0.559) mg;D型果实黄色、小、扁平、长卵形,着生方式为直立,宿存花被膜质,背部无翅状附属物,长为(1.678±0.163) mm,宽为(1.390±0.110) mm,单粒重为(0.928±0.025) mg。A型、B型和C型种子(果实)在5 ℃/15 ℃、5 ℃/25 ℃、15 ℃/25 ℃(暗12 h/光12 h)变温条件下萌发率>68%,且B型和C型种子比A型种子有较高的萌发率和萌发速率。D型种子在3种变温条件下萌发缓慢,最终萌发率始终维持在较低水平(<20%),划破果皮和种皮能够显著提高D型种子的萌发率和萌发指数,表明D型种子处于生理休眠状态。散枝猪毛菜的种子多型性是对荒漠异质环境的一种适应。     

Effects of bird ingestion on seed germination of Sorbus commixta

To determine the effects of ingestion by birds on seed germination, we performed germination experiments in the field and laboratory with Sorbus commixta. The germination of four groups of seeds was compared: ingested seeds, seeds defecated in feces after feeding of fruits to birds; extracted seeds, seeds deliberately extracted from the fruit pulp; juiced seeds, seeds plus the juice of the pulp after seeds had been deliberately extracted from the pulp; intact seeds, seeds in untreated intact fruits. In the laboratory, intact and juiced seeds hardly germinated, but ingested and extracted seeds germinated. Thus, the pulp and its juice appeared to inhibit germination, but seeds could germinate without ingestion by birds once the seeds had been manually extracted from the pulp. In the field, intact fruits did not germinate in the first spring, because the seed was still covered with pulp. The pulp of intact seeds decomposed during the first summer, and thus, the seeds had the potential to germinate during the second spring. In fact, most intact seeds do not germinate during the second spring either, since they lose their viability during the first summer. Thus, under natural conditions, most seeds of Sorbus commixta cannot germinate without bird ingestion. Received: 5 July 1997 / Accepted: 7 November 1997     

蝴蝶兰红花系品种杂交种子形态及胚培养研究

对21个蝴蝶兰自交或杂交组合的种子形态进行观察和无菌培养,结果表明,蝴蝶兰不同组合的种子形态有一定差异,平均种子长、宽及种胚长、宽分别为0.292±0.025 mm、0.073±0.003 mm及0.151±0.009 mm、0.069±0.003 mm。种子萌发率及萌发所需时间因组合而异,平均萌发率为72.4%,原球茎及第一片叶出现所需时间分别为22±3 d、78±6 d,杂交组合启动萌发早、萌发率高。种子启动萌发所需时间、萌发率与果实、种子大小相关不显著,而种子启动萌发所需时间与种胚长、宽呈极显著负线性相关,表明种胚越大,萌发越快。     

Recovery of cassava (Manihot esculenta Crantz) plants from culture of immature zygotic embryos

An embryo culture protocol using immature cassava seeds has been developed to enhance successful seed germination and reduce time for population establishment. Embryonic axes were excised from seeds 40 days after pollination and placed on 1/3 MS medium supplemented with growth factors. Fruits were either air-dried at 20 °C to aid dehiscence, or dissected immediately after harvest. Culture of embryonic axes from seeds obtained from mature fruits (90 days after pollination) served as control. Average percent germination and plantlet recovery rate were higher for embryos cultured from non air-dried immature seeds than from air-dried immature seeds. Immature seeds that were air-dried before germination had ≥50% reduction in germination rate and ≥75% reduction in plantlet recovery rate, indicating that cassava immature zygotic embryos are susceptible to osmotic pressure changes. Genotypic effects were observed in shoot elongation, formation of internodes, and vigor of cultures from both mature and immature seeds. The high percentage of plants recovered from immature seeds through embryo culture opens up opportunities for genetic stock development in cassava that has been previously unexplored. This revised version was published online in June 2006 with corrections to the Cover Date.     

Selection of somaclonal variants with low-temperature germinability in melon (Cucumis melo L.)

Summary Plants were regenerated from adventitious buds and somatic embryos (R₀) of melon (Cucumis melo L.), the cultivar Andes. Somaclonal variants of melon with low temperature germinability were selected from the progenies (R₁) of R₀ plants. Among 5,618 R₁ seeds harvested from 23 R₀ plants that were regenerated from adventitious buds 4 seeds germinated after 5 days of culture at 15 °C (selection rate; 0.07%). However, among 374 R₂ seeds harvested from 2 R₁ plants no seed germinated after 7 days of culture at 14 °C. Among 9,181 R₁ seeds harvested from 50 R₀ plants regenerated from somatic embryos 110 seeds germinated after 5 days of culture at 15 °C (selection rate; 1.20%). Among 3,717 R₂ seeds harvested from 17 R₁ plants 113 seeds germinated after 7 days of culture at 14 °C (selection rate; 3.04%). R₃ seeds were collected from these R₂ plants following self-pollination. Forty-five of the 47 lines (R₃) originated from 10 R₀ plants showed higher germination rates than that of the original cultivar. Selected lines with low-temperature germinability showed greater fruit growth rate than the original cultivar during the middle stage when they were cultivated in a greenhouse under low-temperature conditions. Of fruits harvested from 31 lines, 15 lines showed greater fruit volume than the original cultivar.     

Ecological significance of the aerial seed pool of a desert lignified annual,Blepharis sindica (Acanthaceae)

Reproductive traits of a lignified annual plant, Blepharis sindica were studied in relation to the formation of an 'aerial seed pool' on dead plants in an arid grassland in the Thar Desert of northwestern India. The dead plants remained standing on the soil surface and retained fruits for more than one year. Aerial seed pools developed about 6 cm above the ground. There were no seed pools on or below the ground surface. Only 5.7% of seeds died on dead plants because of insect predation or fungi infection during one year. Seed release was cued by rainfall, and a fraction of seeds on the aerial seed pools was released in each rainfall event. After 13 rainfall events during the monsoon season, 25% of seeds was still retained on the plants. Seed predation on the ground surface was intensive; all cones placed on the soil surface were removed within four days, and 97% of fruits were removed within 10 days. Fifty percent of seeds germinated within 3.5 h, and there were no differences in viability and time required for germination between first year seeds and older seeds. The results indicate that the aerial seed-holding on dead plants is an available way to avoid seed predation in harsh desert environments where seed predation is intense and favorable periods for growth are temporally limited and unpredictable.     

Does perianth colour affect the seed germination of two desert shrubs under different storage periods and conditions?

Haloxylon salicornicum and Salsola vermiculata (Amaranthaceae) are two perennial shrubs producing fruits with differently coloured perianths (yellow vs pink) on separate individuals. To test the impact of different storage periods (four, eight and twelve months) and temperature conditions (freezing, room temperature and natural field temperatures) on the seed germination of the two seed categories, germination tests were carried out on both species. For both species, collected from wild plants in the Arabian desert (Qatar), seed germination was tested under two photoperiods (light 12/12; dark 24 hours) at 20/30°C for winged (intact) and de‐winged seeds. For each species, all the considered factors (perianth colour, wing presence, photoperiod, storage period and storage conditions) had significant effects on seed germination (p < 0.001), while the interactions among factors varied in their level of significance depending on the species. In both species, yellow seeds germinated considerably better than the pink ones, the presence of wings slowed the germination, and both storage period and temperature conditions highly influenced their germination ability. Our results indicate that seeds from different perianth colours have different germination strategies to delay their germination and distribute the species through time by escaping germination time by imposing some kind of after‐ripening or seed dormancy. The variation in storage time and storage conditions might help in extending their germination period, where one set of seeds germinate immediately, and the other set of seeds becomes dormant and thus contributes to the formation of a soil seed bank for the long‐term recruitment of seedlings. This study highlights an ecological advantageous strategy for these two species growing in the unpredictable desert habitat.     

福建厦门几种乡土香化植物的人工繁殖试验

选取4种观赏芳香植物进行人工繁殖试验以提高繁殖效率。播种试验中,深山含笑种子以50 ℃ GA3 300 mg·L^-1溶液人工催芽效果最好,发芽率、发芽势分别比去皮种子增加22.7%和17.3%;单叶蔓荆种子以50 ℃ GA3 1.0 g·L^-1溶液浸泡催芽效果最好,发芽率、发芽势分别比对照增加46.7%和25.4%。以植物生长调节剂预处理扦插枝条,栀子插穗用NAA 100 mg·L^-1 + IBA 100 mg·L^-1预处理,生根率、平均生根数、成活率最高,其生根率和成活率分别比对照增加18.7%和15.8%,平均生根数比对照提高58.9%;络石插穗用NAA 200 mg·L^-1＋IBA 200 mg·L^-1 预处理的生根效果最好,生根率、成活率分别比对照增加24.5%和19.1%,平均生根数比对照提高66.7%。