Preadapted for invasiveness: do species traits or their plastic response to shading differ between invasive and non‐invasive plant species in their native range?

Aim Species capable of vigorous growth under a wide range of environmental conditions should have a higher chance of becoming invasive after introduction into new regions. High performance across environments can be achieved either by constitutively expressed traits that allow for high resource uptake under different environmental conditions or by adaptive plasticity of traits. Here we test whether invasive and non‐invasive species differ in presumably adaptive plasticity. Location Europe (for native species); the rest of the world and North America in particular (for alien species). Methods We selected 14 congeneric pairs of European herbaceous species that have all been introduced elsewhere. One species of each pair is highly invasive elsewhere in the world, particularly so in North America, whereas the other species has not become invasive or has spread only to a limited degree. We grew native plant material of the 28 species under shaded and non‐shaded conditions in a common garden experiment, and measured biomass production and morphological traits that are frequently related to shade tolerance and avoidance. Results Invasive species had higher shoot–root ratios, tended to have longer leaf‐blades, and produced more biomass than congeneric non‐invasive species both under shaded and non‐shaded conditions. Plants responded to shading by increasing shoot–root ratios and specific leaf area. Surprisingly, these shade‐induced responses, which are widely considered to be adaptive, did not differ between invasive and non‐invasive species. Main conclusions We conclude that high biomass production across different light environments pre‐adapts species to become invasive, and that this is not mediated by plasticities of the morphological traits that we measured.     

Internode length in Pisum. Action of gene lw

Jolly, C. J., Reid, J. B. and Ross, J. J. 1987. Internode length in Pisum. Action of gene lw.
Mutant K29 of Pisum sativum L. is shown to possess a recessive gene at a new locus, lw , which results in reduced internode length, delayed flowering and increased symptoms of water congestion compared with the parental cv. Torsdag. The interaction of gene lw with the internode length genes na, le, la and cry ⁵ is examined. Extracts from the shoots of Iw plants are shown to contain similar levels of gibberellin (GA)-like substances to comparable Lw plants, but Iw plants do not elongate to the same extent as Lw plants when treated with GA₁₉ GA₁₉, or GA₂₀. The effect of gene Iw is not graft-transmissible. Unlike essentially isogenic dwarf lines possessing the GA-synthesis genes le, Ih or Is, lw plants show a relative increase in elongation similar to Torsdag in response to photoperiod extensions from sources rich in far-red light. These results suggest that gene lw probably does not reduce elongation by influencing GA-synthesis and that the response to photoperiod extensions with far-red light may depend on the level of GA.     

The effect of a chemical deterrent, released from the frass of caterpillars of the garden pebble moth, on cabbage root fly oviposition

The cabbage root fly, Delia radicum (L.), was deterred from laying eggs on cauliflower plants that had been sprayed with a suspension of the frass of caterpillars of the garden pebble moth, Evergestis forficalis (L.). Polar extracts of the frass deterred oviposition irrespective of the cruciferous plant species on which the caterpillars had been feeding. Non-polar extracts of the frass had no effect. Spraying plants with macerates from Brassica leaves stimulated fly oviposition whereas spraying plants with macerates from garlic mustard leaves deterred fly oviposition. Macerates from the leaves of all other plants tested had no effect. In field experiments the deterrent effect persisted 2–3 days after leaves were sprayed with frass extracts. Plants infested with feeding caterpillars and contaminated with only a few discrete frass pellets were as deterrent to the fly as those sprayed with frass suspensions.

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Résumé D. radicum a évité de pondre sur des pieds de chou-fleur, qui avaient été pulvérisés avec une suspension d'excréments d'E. forficalis. Les extraits polaires de ces excréments empêchent la ponte quelle que soit l'espère de crucifère sur laquelle les chenilles se sont alimentées. Les extraits non polares sont sans effet. Dans la nature, l'action dissuadante persiste 2 à 3 jours après la pulvérisation des feuilles avec les extraits d'excréments. La pulvérisation tous les deux jours a maintenu l'action dissuadante. Des plantes contaminées par des chenilles en train de s'alimenter et souillées par quelques crottes sont aussi dissuadantes pour la mouche que celles pulvérisées avec une suspension d'excréments.

     

湿地松与茶树间作根系分布状况的研究

湿地松(Pinus elliottii)是阳性乔木,茶树(Camellia sinensis)是阴性灌木。这两种树种间作,形成针阔、乔灌两层树冠结构的茶园复合生态系统,可以改善茶树生态条件,提高茶叶的产量和品质。但间作存在胁地现象。一般认为这是上层树木的过度遮荫和根系间的竞争造成的。为了解这两种树种根系的分布状况和相互关系,并为间作茶园的合理配置和加强这种茶园的耕作管理提供依据,我们进行了湿地松与茶树间作根系分布状况的研究。     

Internode length and anatomical changes in Pisum genotypes crys and cryc in response to extended daylength and applied gibberellin A1

Dwarf pea (Pisum sativum L.) plants with genotypes cry^c and cry^s responded differently when an 8 h photoperiod (8 h daylight, 16 h dark) was extended to 24 h (8 h daylight, 16 h incandescent light). Genotype cry^c showed up to a 4-fold increase in internode length, sustained by increases in both cell length (particularly of epidermal cells) and cell number (particularly of cortical cells) while cry^s plants showed up to a 2-fold increase in internode length sustained mostly by an increase in cell number. Under an 8 h (daylight) photoperiod the two genotypes did not differ in their sensitivity to applied gibberellin A₁ (GA₁) and they showed a similar pattern of response. GA₁ significantly increased internode length, cell length and cell number in both genotypes. Incandescent light did not increase the size of the response to GA₁ except for cry^s plants at high dose rates of GA₁ (29–58 nmol). At saturating doses of GA₁ the two genotypes attained a similar peak internode length; incandescent light increased the peak by about 40%. GA₁ increased the rate of leaf appearance by up to 33% while incandescent light reduced the rate by 4–7%. The elongation response of the more mature internodes of cry^c plants to GA₁ or incandescent light was due primarily to an increase in cell length whereas increased cell number made a significant contribution in the case of internodes which were relatively immature at the time the stimulus was applied. The progressive increase in internode length of both genotypes during ontogeny was due primarily to an increase in cell number. In conclusion, alleles cry^c and cry^s (background le La) do not confer a difference in sensitivity to GA₁ and the increase in internode length in response to incandescent light is probably not the result of a real or perceived increase in GA₁ level. Allele cry^s may partially block a phytochrome mediated response to light and the key difference between genotypes cry^s and cry^c may lie in the greater elongation (extensibility?) of cry^c epidermal cells in incandescent light.     

迎接廿一世纪——记中国无锡第十一届国际植物园协会大会

第十一届国际植物园协会（IABG）大会于1993年9月7日在中国无锡开幕,经苏州、杭州,于9月12日在上海闭幕。9月6日部分与会代表参加了在南京举行的“中国南京国际植物园俱乐部”奠基仪式及江苏省重点实验室南京中山植物园“植物迁地保存实验室”扩建部分开放使用等一系列庆祝活动。参加大会的有来自23个国家和地区的199名代表。大会收到论文74篇,其中板报42篇,大会报告13篇。本次会议的主要议题为“植物园与国家发展”。经过大会报告和交流,明确了世界植物园在继续发挥其保护物种和保护环境的功能之外,必须进一步密切植物园与国家发展的关系。全面发展植物园的十项功能,不仅可以增加植物园对社会的贡献,也有利于提高植物园自身的活力和生存能力。大会选出了以主席岩（木规）邦男,副主席李蔼娃、贺善安、安德列也夫,秘书长艾斯特万为领导核心的新一届理事会。世界植物园两大组织国际植物园协会（IABG）和国际植物园保护组织（BGCI）在无锡签署的合作备忘录标志着国际植物园运动进入了一个新的历史时期。理事会的第一次会议于9月11日在由杭州开往上海的火车上举行。讨论了整顿组织、会员登记、出版IABG通讯及与BGCI合作开展活动等问题。会议确认1994年将在印尼召开IABG-AD第二次会议。第十二届IABG大会将于1     

Comparison of carbohydrate utilization and energy charge in the yellow flag iris (Iris pseudacorus) and garden iris (Iris germanica) under anoxia

Carbohydrate and energy metabolism of the flooding- and anoxia-tolerant Iris pseudacorus and the intolerant Iris germanica rhizomes were investigated under experimental anoxic conditions. Rhizomes of I. pseudacorus and I. Germanica were incubated in the absence of oxygen from 0 to 60 and 16 days, respectively. Amounts of glucose, total reducing sugars and non-reducing sugars (starch, fructan and oligosaccharides) in the rhizomes were measured. Ethanol concentration and adenylate energy charge were determined enzymatically. Glucose content of I. pseudacorus rhizomes decreased gradually during the first 30 days under anoxia and then increased at the same time as adenylate energy charge values started to decline. In I. germanica rhizomes the changes were more dramatic and the time scale was much shorter than in I. pseudacorus but the changes were similar. Non-reducing sugar content of I. pseudacorus rhizomes decreased rapidly during the first 15 days under oxygen deprivation and then increased again, to near starting levels at 35 days. In I. germanica the amount of non-reducing sugars decreased gradually during the anoxic incubation. Under aerobic control conditions, adenylate energy charge (AEC) of I. pseudacorus and I. germanica rhizome tissue was 0.87±0.01 and 0.81±0.01, respectively. In I. pseudacorus AEC remained high until 30 days under anoxia. In contrast, the energy charge of I. germanica rhizome tissue remained above 0.6 for 4 days only. Large amounts of ethanol were found in anoxic rhizome tissues of I. pseudacorus (up to 0.21 M ) and I. germanica (0.06 M ) after 45 days and 8 days, respectively. The results are discussed in relation to flooding tolerance of these species.     

一株抗茶炭疽菌和魔芋镰刀菌的淀粉酶产色链霉菌的分离、鉴定及生防潜能

【背景】放线菌是一类重要的生防菌,具有强大的代谢活性,能产生抗生素、酶、酶抑制剂和激素等天然产物抑制病原物生长。【目的】从茶树根际分离得到放线菌,研究候选放线菌对茶炭疽菌和魔芋镰刀菌的抑菌活性及其生防潜能。【方法】分别以茶炭疽病致病菌Colletotrichum camelliae和魔芋茎腐病致病菌Fusarium solani为指示菌,采用土壤稀释涂布法、平板对峙法和菌丝生长速率法,从茶树根际土壤中分离、筛选拮抗放线菌,并根据菌株的形态特征、生理生化特性和系统发育分析结果对其进行分类鉴定,并开展候选放线菌的产促生相关物质和分泌细胞壁水解酶能力的定性检测试验。【结果】共分离得到14株拮抗放线菌,菌株A-dyzsc04-2的拮抗效果最强,被鉴定为淀粉酶产色链霉菌（Streptomyces diastatochromogenes）。该菌株的活菌体对C. camelliae和F. solani的抑制率分别为66.71%±1.23%和71.59%±2.46%,其无菌发酵滤液对2种指示菌的抑菌率均大于90%;此外,菌株A-dyzsc04-2还具有产嗜铁素和葡聚糖酶以及溶解无机磷的能力。【结论】菌株A-dyzsc04-2是一株优良的生防菌,具有较高的开发利用价值,研究结果为菌株A-dyzsc04-2防治茶炭疽病和魔芋茎腐病提供了理论支撑。     

白毫早茶园3种害虫与其捕食性天敌的数量、时间和空间关系

为了合理利用和保护天敌进行卵形短须螨、双斑长跗萤叶甲和假眼小绿叶蝉的综合防治,用灰色系统分析方法和生态位分析法对合肥地区白毫早茶园3种主要害虫与其捕食性天敌在数量、时间、空间等方面关系进行分析,利用害虫与天敌关系密切指数之和综合评判9种天敌与3种害虫关系密切的前四位天敌。2015年卵形短须螨的前四位天敌是鳞纹肖蛸(5.3079)、三突花蟹蛛(5.1716)、锥腹肖蛸(4.8367)和草间小黑蛛(4.7869);2016年前四位天敌依次是三突花蟹蛛(5.3975)、鳞纹肖蛸(4.9414)、茶色新圆蛛(4.8757)、锥腹肖蛸(4.6815)。对两年结果综合分析,卵形短须螨的前四位天敌依次是三突花蟹蛛(10.5691)、鳞纹肖蛸(10.2493)、茶色新圆蛛(9.6353)和锥腹肖蛸(9.5182)。2015年双斑长跗萤叶甲的前四位天敌依次是锥腹肖蛸(5.6926)、异色瓢虫(5.6976)、八斑球腹蛛(5.5101)和斜纹猫蛛(5.4552);2016年依次是茶色新圆蛛(5.2909)、锥腹肖蛸(5.2710)、鳞纹肖蛸(5.1063)和斜纹猫蛛(5.0703)。对两年结果综合评判,双...     

不同培肥措施对红壤茶园土壤微生物量碳的影响

研究了经过4年不同培肥措施后红壤茶园土壤微生物量碳变化.结果表明:稻草覆盖后不同比例有机无机肥配施、间作三叶草以及全施化肥处理对土壤微生物量碳均有明显提高;全年土壤微生物量碳年变化都呈现"低-高-低-高"的趋势,且在不同时期对微生物量碳的影响不同;与对照(CK)相比,稻草覆盖 100%有机肥(T1)、稻草覆盖 75%有机肥 25%化肥(T2)、稻草覆盖 50%有机肥 50%化肥(T3)、稻草覆盖 25%有机肥 75%化肥(T4)、100%化肥(T5)和间作三叶草 不施肥(T6)土壤微生物量碳全年平均值分别高出17.05%、32.38%、32.05%、24.30%、26.23%和24.63%,且差异均达到显著水平(P＜0.05);土壤微生物量碳与活性有机质、土壤全氮、微生物量氮、微生物量磷呈显著正相关,与速效氮、土壤全磷、土壤全钾、土壤含水量之间关系不显著;与单施化肥和全量投入有机物料相比,有机物和化肥配合施用更有利于提高土壤肥力.