不同降水量处理时5种蒿属植物瘦果粘液溶出

用粘沙法对科尔沁沙地西部5种蒿属植物冷蒿(Artemisiafrigida)、差巴嘎蒿(A.halodendron)、大籽蒿(A.sieversiana)、黄蒿(A.scoparia)、乌丹蒿(A.wudanica)进行了瘦果粘液溶出及粘沙量的比较。主要模拟埋深5mm、降水量为1、2、4、8mm时瘦果的粘液溶出。5种供试植物均有粘液瘦果。在降水量1mm时,供试植物的粘液瘦果就能溶出粘液。当降水量达到2～4mm时,典型的沙生植物乌丹蒿和差巴嘎蒿的粘液瘦果粘沙量平均值分别达到7.31～13.56mg、0.63～2.55mg。除冷蒿外,其它4种植物均有随降水增多、粘液溶出量加大的趋势。粘液瘦果比例从大到小的排序是冷蒿>乌丹蒿>差巴嘎蒿>大籽蒿>黄蒿。在各种处理时,粘沙瘦果百粒瘦果粘沙量由大到小的顺序是乌丹蒿>差巴嘎蒿>大籽蒿>冷蒿>黄蒿。溶出粘液粘沙后,冷蒿瘦果所形成沙团重量达到瘦果重量的5～7倍,差巴嘎蒿2～9倍,大籽蒿3～5倍,黄蒿5～8倍,乌丹蒿5～29倍。流沙先锋植物乌丹蒿和差巴嘎蒿百粒瘦果粘沙量较其它植物大、在较低降水量时这两种植物粘液瘦果粘沙量较大表明瘦果溶出粘液粘沙是植物针对沙地流动性的进化适应之一。     

小车前（Plantago minuta Pall.）种子表面粘液物质的吸水特性及其对种子在干旱环境中萌发的影响

为了理解荒漠短命植物小车前(Plantago minuta Pall.)种子表面的粘液物质对种子在干旱环境中萌发的作用,在室内控制条件下研究了粘液物质的吸水保水特性、剥离粘液物质的种子(无粘液种子)和保留粘液物质的种子(粘液种子)在-1.15～-0.15 MPa不同渗透胁迫条件下的萌发状况.结果表明: (1)小车前种子表面的粘液物质干重占粘液种子干重的5.6%;在去离子水中,粘液物质可以吸收相当于其自身干重217.1倍的水分;粘液物质的存在使得小车前种子的吸水倍数由2倍增加至14倍,从而保证为种子萌发提供充足的水分;(2)干燥的粘液种子吸水2h后即达到饱和,而吸水饱和后的粘液种子在室温下晾置,经过48h后又干燥失水恢复至原重;(3)在去离子水中或低渗透胁迫(-0.33～-0.15 MPa) 条件下,粘液物质吸水作用能促进小车前种子萌发,粘液种子3d的发芽势和10d的总萌发率均显著高于无粘液种子;在高渗透胁迫(-1.15～-0.73MPa)条件下,粘液种子3d的发芽势显著低于无粘液种子的,而10d的总萌发率与无粘液种子的没有显著差别,表明粘液物质在干旱条件下可能从种子而非外界环境中吸取水分,减缓了种子萌发速率.通过上述结果可以认为小车前种子表面的粘液物质在早春干湿交替剧烈的荒漠生境中起到通过调节水分来调节种子萌发的作用,这种萌发策略大大降低了因大批种子同时萌发导致幼苗受旱甚至种群灭亡的潜在风险.     

丹参种子的吸水特性及发芽条件研究

丹参(Salvia miltiorrhiza Bunge)种子具有快速吸水的生物学特性,在10℃和25℃下,种子入水10min后吸水量即可达到种子原重的4．5倍左右,至2h吸水量分别达到原重的10．5和11．7倍。温度对种子的吸水速率无明显的影响。丹参种子发芽的最适宜温度在25～30℃,在实验室条件下,采用滤纸床25℃时,一级种子发芽率可达83％,混级种子为74％。同时发现,预先冷冻、PEG—4000引发和GA3浸种处理可以明显提高丹参种子的发芽率。采用超声波处理和PEG引发技术可以使贮藏1a的陈种子发芽率达到45％以上。     

奶牛排卵前后宫颈粘液中氨基酸含量的变化

为了研究母体排卵前后受精环境的变化,测定了27头奶牛排卵前和排卵后宫颈粘液中的氨基酸含量,测定结果表明,宫颈粘液的氨基酸含量排卵前平均为1032μg/mL,排卵后平均为2380μg/mL,排卵后为排卵前的2．3倍（Table 1)。排卵前,宫颈粘液中含量比例最高的氨基酸是谷氨酸和苏氨酸,分别占氨基酸总量的12．8％和12．2％,含量比例最低的最组氨酸,只占2．2％,这种比例在排卵前后都是比较稳定的（Table2)。排卵后,宫颈粘液中氨基酸比较普遍下降的是苏氨酸,比排卵前平均下降19％,排卵后普遍增加的是赖氨酸,比排卵前平均增加25％（Table 3)。Fig.1表明：排卵前后,宫颈粘液中均不含游离氨基酸。体液中的氨基酸代谢是一种重要的生理活动,排卵后宫颈粘液中苏氨酸含量普遍降低,赖氨酸含量普遍增加的生理活动反映了这些氨基酸相关的蛋白成分发生了变化,这些蛋白成份的变化有否生理意义,是否对卵与X或Y精子的结合产生影响,有待深入研究。     

盐生野大豆的异黄酮积累及其生态学意义

以自然生长在盐碱地上的野大豆(Glycine soja)和不耐盐的栽培大豆(G. max)为材料,测定了它们在不同盐度条件下叶片、根部和种子的异黄酮含量,并测定了它们叶片的L-苯丙氨酸含量和苯丙氨酸裂解酶(PAL)活性,还测定了它们根部的结瘤量和固氮酶活性。通过两者比较,分析了它们的大豆异黄酮代谢和盐渍环境的关系。结果表明:盐渍处理不抑制盐生野大豆PAL酶的活性,其大豆异黄酮大量积累;相反,盐渍处理明显抑制栽培大豆PAL酶活性,其大豆异黄酮含量减少,而大豆异黄酮合成前体L-苯丙氨酸积累。结果还显示:在盐渍条件下,盐生野大豆根部异黄酮积累的同时,其根瘤结瘤量较多,且固氮酶活性也较高;而栽培大豆随着其根部异黄酮的减少,其根瘤结瘤量大大减少,且固氮活性大大下降。野大豆和栽培大豆的这些差别说明:盐生野大豆积累大豆异黄酮有其生态学意义,这很可能是野大豆通过异黄酮次生代谢途径适应盐渍环境的一种重要机制。     

濒危植物银杉种子特征的研究

同一株银杉的不同珠果的出种量没有明显差异,说明就同一植株而言,其有性生殖是同步,球果的发育程度比较接近。银杉种子的平均重量０．００１９７ｇ,仅为乔木树种种子平均重量的６％。种子中空粒比例达１６．２４％,反映出较高的种子败育率,饱满的种子中有生活力者仅占５３．５％,银杉种子的吸水过程有３个明显的阶段,０－１ｈ是急剧吸水阶段,１－９ｈ吸水基本停滞９ｈ到１４ｄ吸水果又呈递增趋势。在同样贮藏条件下,播种环     

盐生车前根液泡膜ATPase对盐胁迫的响应

用蔗糖密度梯度离心法从对照和盐处理的盐生车前根中分离出液泡膜,并对其ＡＴＰａｓｅ某些特性进行了比较研究,蔗糖连续密度梯度离心后ＮＯ＾－３敏感的ＡＴＰａｓｅ活性主要分布在２２％－３５％蔗糖浓度之间,用不连续密度梯度离心法从２２％－３５％界面收集到的膜主要源于液泡膜。因为,这种膜ＡＴＰａｓｅ活性受到Ｃｌ＾－的促进和ＮＯ＾－３的强抑制,而叠氮化钠和正钡酸钠只抑制酶活性的１０％左右,最适ｐＨ８．０。     

野皂荚豆及其化学成分的研究

经测定野皂荚豆中粗蛋白含量达２２．１２％,内胚乳占种子组成的４１．３７％。通过纸层析、高效液相色谱及药外光谱分析表明内胚乳中含有６６．７％的半乳甘露聚糖,半乳糖与甘露糖配比为１：３．２。本文为综合开发利用野皂荚豆资源提供了科学依据。     

罗布麻播种方法试验报告（摘要）

罗布麻种子细小,幼芽顶土力较弱,在适宜的温度下播种深度3mm左右,保持土表湿润疏松,才能保证正常出苗。试验用陕西红麻,分两期播种：（1）4月14日;（2）5月6日。处理分：1．蓄水撒播法：播前灌足水,后整地,再将催分物种子与沙混合筛入畦内。2．蓄水点播法：灌水整地同上,种子点地畦内。3．垄播沟灌法;种子播垄上,然后灌水。4．干播覆沙洒水勤浇法,播前细致整地,播后浅覆沙,出苗前经常用喷壶酒水。5．落水播种法（对照）;整地后灌水10－15cm深,在水未渗下时,将催分芽的种子放入盆内水中,用手将种子与水泼撒和畦内,等地面稍干后再覆盖细土或沙。试验结果：（1）期播种,出苗率以垄播沟灌最高（90．1％）,保苗率以蓄水点播最高（87．0％）。（2）期播种,出苗率以落水播种最高（75％）,保苗率以蓄水点播最高（91．8％）。根据苗期生长情况（包括茎高,根长,苗鲜重等）综合考虑,则以干播覆沙洒水勤浇法最优,其次为蓄水点播法,其它播种方法也都有一定的应用价值。罗布麻的落水播种法是在新疆,甘肃等内陆干旱区总结出的成功经验,并且在实践中一贯采用,由于内陆干旱区大气与土壤均较干旱,水分供应是首要条件,又因当地土壤下层含盐量大,生长季节蒸发量大,勤浇势必造成盐分上升。落水播种法在播前一次将水灌中,出苗前不再浇水,所以有利出苗,保苗,但在陕西关中以及沿海等地区,雨水较多,土壤较湿润,若春季土壤湿度过大,土温上升缓慢,对出苗反为不利。在（1）,（2）两次播种期比较时,亦看出这种趋势。因此,在陕西关中平原地区采用干播洒浇法或蓄水点法播法有一定的优越性。在低湿易涝处,更有进行垄播的必要。总之,罗布麻的播种方法,可根据捉苗要领,在具体条件下灵活掌握。     

福州地区桑白蚧发生动态和药剂防治试验

桑白蚧在福州地区一年发生4代．以雌成虫在寄主枝干上越冬．越冬代(第4代)一雌虫产卵量多的达278粒．少的36粒,平均171粒,比第2代产卵量多2．6倍．比第3代多4．5倍．药剂防治试验结果,在2龄幼蚧高峰期,用25％扑虱灵可温性粉剂1500倍液,40％氧化乐果乳油800-1000倍液和95%机油乳剂50—100倍液喷雾．防治效果可达90％左右．用25％扑虱是可湿性粉剂1000-1500倍液．喷酒幼蚕触杀试验和喷洒桑叶喂蚕胃毒试验结果．对幼蚕安全．用扑虱灵防治桑树上的桑白蚧,对养蚕业无不良影响。     

Seed Morphology of Plantago in China and Its Taxonomic Significance

Studied in this work was seed morphology of the genus Plantago (2 subgenera, 8 sections, 17 species and １ variety )in China. The sculpture was observed under scanning election microscope. Four forms of seed morphology are recognized as follows: (1)Multi-angular type: seeds are variously angulate, yellow-brown or black, 6-30 in a fruit; seed-coat sculpture ranges from reticulate to papillate. It occurs in Subgen. Plantago Sect. Polyneuron: P. scheideri, P. denstflorus, P. major, P. hostifolia, P. asiatica, P. erosa and P. centralis. (2) Navicular type: seeds are navicular, yellow, brown to black, 2 in a fruit; seed-coat sculpture is reticulate. It was found in Subgen. Plantago Sect. Novorbis: P. virginica; Sect. Arnoglossum: P. lanceolata; Sect. Leucopsyllium: P. minuta, P. lessingii and P. aristata and Subgen. Psyllium Sect. Psyllium: P. indica. (3)Ovoid type: seeds are long-ovoid, yellow-brown, black and lustrous. Seed-coat sculpture scali-ratiform. P. maxima in Subgen. Plantago Sect. Lamprosantha belongs to this type. (4)Recti-circular type: seeds are recti-circular, yellow-brown, black, 1-2 or 4-5 in a fruit; seed-coat sculpture is reticulate and papillate. It was found in P. maritima var. salsa of Subgen. Plantago Sect. Coronopus and P. depressa, P. camtschatica and P. arachnoidea of Sect. Mesembrynia. The seed morphology and seed-coat sculture exhibit specific characters, by which some of confused species can be clarified and a new species, P. densiflorus J. Z. Liu. is established. The present author’s seed morphology classification is in accordance with Pilger’s systemof the genus, which was established using other features.     

Karyotypes and C-values of Two Plantago Species from the Qinghai Tibet Plateau,China

The chromosome numbers, karyotypes and C values of 18 populations of Plantago depressa and 2 populations of Plantago major from the Qinghai Tibet Plateau, China, were reported in the present study. The results were as follows: the chromosome numbers of P. depressa populations from Yadong County and Nyingchi County of Tibetan Autonomous Region (TAR) were 2n=4x=24, other populations of Pdepressa and Pmajor were 2n=2x=12, and the basic chromosome number of all populations was x=6. All karyotype types were 1A, and the karyotype constitutions were not completely consistent with previous reported results. The 2C value of Pdepressa was reported for the first time, and the 1Cx vaule tended to decrease with increasing ploidy levels. Meanwhile, the 2C value of Pmajor was not identical with previous existing results. The results showed that the variation of 2C value occurred at the inter population level of Pdepressa and Pmajor, also flow cytometry couldn′t be used to estimate the ploidy of the genus Plantago Linn.     

Male sterility, protogyny, and pollen-pistil interference in Plantago maritima (Plantaginaceae), a wind-pollinated, self-incompatible perennial

Evolution and maintenance of male sterility in seed plants can be explained by the maternal inheritance of mitochondria, which encode the trait, and by adaptive functions that enhance female fecundity in male-sterile compared to hermaphrodite individuals. Protogyny and male sterility can independently decrease the negative effect of pollen-pistil interference in self-incompatible species. In Plantago maritima, which possesses both traits, protogyny increases seed set in hermaphrodite individuals. This is shown both by a significantly positive association between seed set and retarded dehiscence of the anthers and by a more than 50% reduction in seed set following self-pollination. Male sterility does not seem to increase seed set further, as female and hermaphrodite plants do not differ significantly in mean seed set per capsule. Bagging experiments demonstrate strong self-incompatibility in the study populations. Hence, in P. maritima male sterility seems neither to prevent selfing nor to reduce the effect of pollen-pistil interference. Females had significantly larger stigmas than hermaphrodites, but seed set varied negatively with stigma length among females, indicating that the evolution of unisexuality in P. maritima is not due to prefertilization sex allocation. I therefore conclude that the genetical system of nucleocytoplasmic determination of gender is the main cause for maintenance of male sterility in P. maritima.     

三种药用车前的染色体数目和核型的研究

<正> 车前为常用中药材,《神农本草经》和明李时珍的《本草纲目》中列为上品,以干燥全草及种子入药,有清热、明目、利尿、止泻、降低血压和镇咳祛痰等功效。 本文报道了作为“车前”中药材的三种车前属Plantago L.植物:大车前P. major L.车前P. aslatica L. 和平车前P. depressa Willd.染色体数目和核型的资料,旨在为探讨车前属内的分类和进化及为提高车前中药材的产量和质量的研究提供必要的细胞学资料。     

朱唇种子吸水特性及其在干旱胁迫下萌发特性

种子粘液质是植物在长期适应环境过程中形成的,该物质对于种子的扩散、定居、生存力的改善、萌发、幼苗生存乃至抵御有毒化学物质毒害等都具有重要的生态学意义。朱唇为唇形科鼠尾草属多年生草本植物,原产美洲热带地区,现已广泛栽植于世界各地。为了理解朱唇种子表面的粘液物质吸水特性和种子在干旱胁迫下的萌发特性,该研究以朱唇种子为材料,运用光学显微镜和扫描电子显微镜观察以及种子萌发试验的方法,对种子和粘液层的形态结构、粘液质对种子萌发的影响进行了研究。结果表明:朱唇种子为卵形,表面为负网状结构,千粒重为(1.611±0.0084)g,无粘液种子吸水倍数为3,粘液种子吸水倍数为25,粘液层吸水倍数为122。粘液和无粘液种子及粘液层的重量都随吸水时间的延长而增长,但脱水过程要远长于吸水过程。朱唇种子吸水2 h达到饱和,经过36 h可干燥失水恢复原重。不同浓度PEG对朱唇种子的萌发均有影响,发芽势随PEG浓度升高而显著降低。朱唇种子在5%PEG胁迫下发芽率最高达(90.00±8.66)%,20%PEG胁迫下发芽率最低为(76.67±10.41)%,低浓度PEG对朱唇种子萌发有一定促进作用。这说明朱唇种子为速萌型种子,其粘液质在种子吸水过程中起到举足轻重的作用,能保证短时间内有充足的水分供其萌发。     

Effects of mucilage on seed germination of the desert ephemeral plant Plantago minuta Pall. under osmotic stress and cycles of wet and dry conditions

To test the role of the seed mucilage of Plantago minuta Pall. in regulating germination under osmotic stress and cycles of hydration and dehydration, two experiments were carried out using seeds with intact mucilage and mucilage‐free seeds. In Experiment 1 seeds were immersed in a range of iso‐osmotic polyethylene glycol solutions (?1.15 to 0 MPa) for 14 days; any ungerminated seeds were transferred to deionized water to investigate the recovery germination. In Experiment 2 seeds were immersed in deionized water for 24 h, and were then incubated on filter paper for an additional 13 days to ensure complete desiccation before reimbibition to test the germination recovery percentage. Under mild osmotic stress (?0.73 to 0 MPa), the intact seeds with mucilage were shown to have higher germination rates than the mucilage‐free seeds, indicating that the mucilage led to a “fast sprouting” germination strategy under mild osmotic stress. However, when seeds were exposed to high osmotic stress (?1.15 MPa), the mucilage apparently slowed the germination rate, resulting in a “risk‐balancing” germination strategy. Extreme drought induced by polyethylene glycol solution and the desiccation pretreatment accelerated germination rates compared to non‐pretreated seeds; both germination potential and recovery percentage of the mucilage seeds were significantly higher than that of the mucilage‐free seeds. Our results revealed that the seed mucilage of P. minuta plays a crucial role in regulating seed germination rates and the germination strategies adopted by controlling seed water absorption when the seeds experience different osmotic stresses or alternating wet and dry conditions.     

The Impact of Herbivory and Competition on Flowering and Survival during Saltmarsh Succession

Abstract: For succession, the establishment and turnover of plants, in terms of generative spreading and renewal, is of crucial importance. Especially the success of seedling establishment into the existing vegetation might be of prime importance for the further development of plant species composition. Flowering, on the other hand, is the necessary first step towards generative output and later seed set. In a chronosequential gradient of a saltmarsh succession, we investigated the performance of transplants of three common species under different conditions: Artemisia maritima, Atriplex portulacoides and Plantago maritima were transplanted as seedlings and mature plants into plots in early-, mid-, and late-successional stages (15, 30 and 40 years) on the Dutch island of Schiermonnikoog. Natural herbivory (by hares and geese) and neighbourhood competition were excluded in a factorial design. Flowering and survival rates of the three species were generally greatly reduced under natural conditions, compared to competition- and herbivory-free plots. The survival rates of Artemisia maritima and Plantago maritima reflect their position as early-successional species: early in succession, both show their highest survival and abundance. For late-dominant Atriplex portulacoides a different explanation has to be invoked for the medium-high survival and low abundance: probably winter grazing by hares and the importance of a high nitrogen supply rate, rather than flowering and survival, determine its low abundance in the early and mid-phase of this saltmarsh succession. Some long-term impacts of herbivores affecting flowering and survival are discussed.     

Na+/H+ antiport activity in tonoplast vesicles from roots of the salt-tolerant Plantago maritima and the salt-sensitive Plantago media

Plantago species differ in their strategy towards salt stress, a major difference being the uptake and distribution of Na⁺ ions. A salt-sensitive ( Plantago media L.) and a salt-tolerant ( P. maritima L.) species were compared with respect to Na⁺/H⁺ antiport activities at the tonoplast. After exposure of the plants to 50 m M NaCl for 6 days isolated tonoplast vesicles of P. maritima showed Na⁺/H⁺ antiport activity with saturation kinetics and a K_m of 2.4 m M Na⁺, NaCl-grown P. media and the control plants of both species showed no antiport activity. Selectivity of the antiport system for Na⁺ was high and was determined by adding different chloride salts after formation of a Δ pH in the vesicles. Specific tonoplast ATPase activities were similar in the two species and did not alter after exposure to NaCl stress.     

新疆短命植物抱茎独行菜种子粘液质特性的研究

以新疆荒漠植物抱茎独行菜为材料,运用光镜与扫描电镜观察以及紫外吸收光谱法、化学反应及种子萌发实验等方法,对粘液质的形态和结构,物理化学特性,粘液质对种子萌发及萌发后的影响进行了研究.结果显示:(1)完整干种子表面覆盖着一层膜状物质(完全脱水的粘液质),并呈同一走向的山脊状突出的网状结构,遇水后粘液物质呈射线状向外发射出来,化学反应实验结果表明,粘液质的组成可能是某种多糖,如β-葡聚糖.(2)粘液质约占干种子重量的1/4,有很强的吸水能力,完全浸润10 min后,种子重量增加约30~40倍,种子长度、宽度、厚度的增加分别多于1倍、2倍、4倍;完全润湿的种子能够粘附相当于其干种子重量68倍的沙粒.(3)种皮粘液质对于不同土壤基质中的种子萌发有重要作用,但是对萌发后幼苗的生长没有作用.     

Population size, female fecundity, and sex ratio variation in gynodioecious Plantago maritima

Theory predicts that the sex ratio of gynodioecious populations (in which hermaphrodites and females coexist) will be affected by the relative female fitness of females and hermaphrodites, and by founder events and genetic drift in small populations. We documented the sex ratio and size of 104 populations of the gynodioecious, perennial herb Plantago maritima in four archipelagos in eastern Sweden and western Finland (from latitude 53 to 64 degrees N). The sex ratio varied significantly both among and within archipelagos (range 0-70% females, median 6.3% females). The frequency of females was highest in the northernmost archipelago and lowest in the southernmost archipelago. As predicted, females were more frequently missing from small than from large populations, and the variance in sex ratio increased with decreasing population size. The relative fecundity of female plants (mean seed output per female/mean seed output per hermaphrodite) ranged from 0.43 to 2.16 (median 1.01, n = 12 populations). Among the 12 populations sampled for seed production (four in each of three archipelagos), the frequency of females was positively related to relative fecundity of females and negatively related to population size. The results suggest that the local sex ratio is influenced both by the relative fecundity of females and hermaphrodites and by stochastic processes in small populations.