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1.
Using diploid strains of Saccharomyces cerevisiae and S. ellipsoideus,the following facts were found:
  1. Indole-3-acetic acid, 2,4-dichlorophenoxyacetic acid and -naphthaleneaceticacid produced stable variants differing in the cell form andin the response to the actions of auxin to elongate cells, toinduce respiration- deficient mutation and to promote sporulation.
  2. The auxins also produced stable variants differing in theabilityto form spores.
  3. Acetic acid had no above-menthionedactions of auxin.
  4. Spore-formation and cell elongation of someof auxin-inducedvariants were controlled by auxin.
Biological significance of the auxin-induced variation is discussedand the usefulness of some of these variants as experimentalmaterial for auxin physiology in general is pointed out. (Received November 1, 1966; )  相似文献   

2.
植物生长调节剂对龙眼内源激素及花芽分化的影响   总被引:17,自引:0,他引:17  
研究了PP333和GA对龙眼(DimocarpuslonganaLour),成花的作用及其与内源激素的关系。结果表明,PP333处理后,iPA含量明显高于GA的处理,而GA含量则呈现由高到低逐渐下降的趋势,GA处理正好相反,PP333处理后芽中的ABA含量明显低GA处理,表明高含量的GA和ABA不利于花芽分化,而高含量的细胞分裂素则有利于花芽分化,外施P333可缩短花序长度,提高着果率和增加产量。  相似文献   

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In order to enhance phytoremediation efficiency, we investigated the effects of dual inoculation with ectomycorrhizal fungi and the ectomycorrhiza associated bacteria Micrococcus luteus and Sphingomonas sp. on the growth and metal accumulation of willows (Salix viminalis x caprea) on contaminated soil. The bacterial strains were previously collected from sporocarps of ectomycorrhizal fungi. The bacteria increased plant growth and the mycorrhizal dependency of willows colonized with the ectomycorrhizal fungus Hebeloma crustuliniforme. The total cadmium (Cd) and zinc (Zn) accumulation in the shoot biomass was increased after inoculation with the fungal strain Hebeloma crustuliniforme in combination with Micrococcus luteus up to 53% and in combination with Sphingomonas sp. up to 62%, respectively. The dual inoculation in combination with Laccaria laccata did not increase the accumulation of Cd and Zn in the willows. We conclude that associated bacteria can enhance the ectomyorrhiza formation and growth of willows and, thereby, the Cd and Zn accumulation in the plant biomass. The results suggest that bacterial support of root growth promoting ectomycorrhizal fungi may be a promising approach to improve the remediation of metal-contaminated soils by using willows.  相似文献   

5.
本文就赤霉素、细胞分裂素、乙烯利对果实生长发育的调控作用进行了较为系统的论述,并对其在果树上的利用方法、时期、浓度等作了说明。  相似文献   

6.
金钱松胚外植体在培养过程中由于外源激素的种类和配比的不同而存在着几种发育途径:直接从胚外植体表面分化不定芽;先诱导愈伤组织,再从愈伤组织分化不定芽;还可由愈伤组织分化出胚状体。激素BA对外植体不定芽的诱导起着关键作用。激素2,4-D则诱导愈伤组织,BA与2,4-D配比恰当诱导的愈伤组织分化出体细胞胚状体。 LP’附加低浓度的BA或KT(<0.5mg/L)促进不定芽茎的伸长; LP’附加浓度的IBA(<0.5mg/L)诱导不定根的发生。愈伤组织在基本培养基浓度为 ×LP’或1×LP’的分化培养基上不定芽诱导率相似。  相似文献   

7.
水位梯度对湿地植物生长、繁殖和生物量分配的影响   总被引:46,自引:2,他引:46       下载免费PDF全文
本文考察了水位梯度对武夷慈姑(Sagitariawuyiensis)、小慈姑(S.potamogetifolia)、野荸荠(Eleocharisplantagineiformis)和锐棱荸荠(E.acutangula)植物幼苗生长、繁殖器官干重、生物量及其分配式样的影响。实验表明:植物高度、生物量及其分配对水位梯度的反应在种间有一定差异,而慈姑属植物的叶数、荸荠属植物的秆数、繁殖器官干重等对水位梯度处理的反应在种间有一定相似性。综合植物生物量和繁殖的反应特点,可以认为武夷慈姑和锐棱荸荠适宜生长在0~5cm水深处,小慈姑在20cm水深处生长较佳,而野荸荠适宜于0~20cm范围。结果提示:湿地植物的空间分布与其对水位反应的差异性有一定关系。  相似文献   

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芒萁植株浸出液对几种植物生长的影响   总被引:12,自引:0,他引:12       下载免费PDF全文
 芒萁在天然植物群落中具有较强的竞争能力和对其它植物的排斥作用。在研究中必须注意其化学分泌物对其它植物的抑制作用,以利荒山灌木草丛的经济利用。作者选取马尾松、猪屎豆、天兰苜蓿、紫苜蓿、葛藤、红车轴草、白车轴草及禾本科的牛尾草、块茎虉草进行栽培试验证明,芒萁植株的浸出液对马尾松以外的其它试验植物均有抑制作用。  相似文献   

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Allelopathic effects of submerged macrophytes on the growth and photosynthesis of different unialgal cultures of planktonic cyanobacteria, a diatom, and a green alga were tested in coexistence experiments using dialysis cultures. The method applied allowed measurements under conditions similar to that in lakes but without nutrient and light limitation. Growth and photosynthesis were measured with a pulse amplitude modulated fluorometer as an increase of chl a fluorescence and activity of PSII, respectively. Eurasian water milfoil Myriophyllum spicatum L. and rigid hornwort Ceratophyllum demersum L. proved to inhibit the PSII activity and then growth of the investigated phytoplankton species, whereas sago pondweed Potamogeton pectinatus L. showed no effect. Growth inhibition was dependent on biomass of M. spicatum. Considerable differences between phytoplankton groups and among species of cyanobacteria were found regarding their response to M. spicatum. Members of the Oscillatoriales and Microcystis aeruginosa Kütz. emend. Elenkin were more sensitive than the cyanobacterium Aphanizomenon flos‐aquae Ralfs ex Born. et Flah., the diatom Stephanodiscus minutulus (Kütz) Cleve et Möller, and the green alga Scenedesmus armatus Chodat. A possible contribution of this result to changes in the phytoplankton succession of lakes after loss of macrophytes is discussed.  相似文献   

13.
许纲  钦俊德 《昆虫学报》1987,(4):359-366
实夜蛾属(Heliothis)的棉铃虫(H. armigcra)和烟青虫(H. assulta)是近缘种,幼虫期取食多种相同的植物,其中含有不同的次生物质.本项工作是在人工饲料中分别加入0.5%的烟碱、番茄苷、棉子酚、丹宁酸等饲养早期六龄的幼虫,测定它们对生长和食物利用的影响.结果表明这些次生物质对两种幼虫有不同的作用:烟碱对棉铃虫没有明显影响,但对烟青虫的取食却有一定的刺激作用.丹宁酸、棉子酚、番茄苷可抑制两种幼虫的生长,而以番茄苷抑制烟青虫的生长最为显著.番茄苷主要通过抑制取食来影响幼虫的生长,而丹宁酸和棉子酚则具有降低消化率的作用.通过次生物质对这两种幼虫效应的比较可知,棉铃虫有较大的忍耐力.  相似文献   

14.
30种园林植物对短期大气污染的生理生态反应   总被引:39,自引:0,他引:39       下载免费PDF全文
 30种2~3年生园林植物分别盆栽于不同污染强度的工业生产区、交通繁忙区和相对清洁区,在第一生长季结束后对各试验区植物叶片气体交换特征参数进行测定,评价了大气污染对不同植物种类的可能影响效果。结果表明:工业污染区和交通繁忙区均有较高的SO2浓度,交通繁忙区NOx浓度明显高于其它试验区。根据综合污染指数,3个试验区污染强度为交通繁忙区>工业污染区>相对清洁区。生长在污染区的大多数植物的净光合速率(Pn)、蒸腾速率(E)和气孔导度(gs) 均出现不同程度的下降,下降幅度因植物种类不同而有较大差异。植物Pn、E与gs之间存在显著线性相关关系,表明多数植物能够感应污染胁迫和调节气孔开张度,是植物对胁迫环境的一种适应策略。但是污染胁迫下Pn、E与gs线性相关的显著程度被削弱,表现出污染胁迫下不同植物种类Pn和E的变化与gs变化的不协同性和复杂性。根据Pn下降程度可将植物分组为轻度敏感(11种)、中度敏感(11种)和高度敏感植物(8种)。   相似文献   

15.
我们推导了一个为达到一定的P_(AO_2)所需要的计算公式。据此对被试者制定了在5km高度上P_(AO_2)=5.9kPa和在7km高度上P_(AO_2)=4.4kPa的引导呼吸曲线。引导被试者有意识地控制呼吸,使呼吸频率和幅度尽量同引导曲线一致。结果表明,引导呼吸同自然呼吸相比,被试者的和Sao_2有显著提高。心电图T波幅度降低较少,在5km降低了循环功能障碍发生率,在7km降低了意识障碍发生率,减轻了缺氧症状。  相似文献   

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Eight diatom species (Chaetoceros pseudocurvisetus Mang ., Stephanodiscus hantzschii Grun ., Skeletonema costatum ( Grev.) Cleve , Asterionella formosa Hass ., Thalassiosira nordenskioeldii Cleve , Detonula confervacea ( Cleve) Gran , Chaetoceros sp., and Nitzschia frigida Grun.) were isolated from various temperature environments ranging from temperate to the Arctic, and their growth responses to temperature were determined. Each species grew over a different temperature range. The lower and upper limits of each species varied from −1.8° to 20° C and from 2° to 30° C, respectively. The width of the growth range of each species. also varied from 3.8° to 25° C, and the growth of these species was observed, as a whole, between a wide temperature range from −1.8° to 30° C .
Within the growth temperature ranges, the growth rate of each species increased with temperature until reaching a maximum, which was followed by a steep decrease up to the upper limit of the growth range. As a result, each species showed a maximum rate at the temperature very near to the upper limit, which was generally higher than the isolation temperature. The specific growth rates were compared among the eight species. The interspecific maximum rate at each temperature exhibited an exponential increase with a Q10 = 1.48. The relative growth rates of each species were calculated by normalizing the specific growth rates with the interspecific maximum rate at each respective temperature. The higher relative growth rates tended to occur at the isolation temperature of each species, suggesting that temperature is a significant control on species distributions in nature .  相似文献   

19.
Abstract  Electroantennogram responses (EAGs) to 39 plant volatiles from Aphis glycines, A. gossypii and Myzus persicae were recorded. The olfactory system of these three aphid species differentially responded to green leaf, aromatic, mono-and sequiterpene chemicals. The EAG depolarizatin to green leaf chemicals and their isomers were more pronounced than to terpenes, alcohols and aldehydes, 6 carbon atom compounds being the most effective. It was shown that there was certain difference in the olfactory spectra of these three aphid species to plant volatiles. Higher responses in A. glycines and A. gossypii were elicited by the leaf aldehydes and esters than by the corresponding alcohols, which are in contrast with those in M. persicue . The activity of aphid olfactory system was related to molecular structures of the compounds. The responses to saturated alcohols and aldehydes were higher than those to unsaturated. The responses of spring emigrants of A. glycines to terpene derivatives (alcohols, aldehydes and esters) were higher than those of A. gossypii , but were lower to terpene hydrocarbons. The dissimilarity in olfactory spectra of the aphid species reflected the evolution of their host plant selection specificity. In the evolution, their chemosensory system adapted to perceive host plants. The shapes of the EAGs evoked by the various components were consistently different, with the slowest recovery for geraniol, 1-decanol and (±)-β-cit-ronellol, and ware related to number of carbon atoms in straight chain saturated alcohols.  相似文献   

20.
用触角电位法研究了大豆蚜、棉蚜和桃蚜对39种挥发性次生化合物的反应,结果如下:1)绿叶气味化合物及其异构体的去极化电压远强于萜烯类;具有6个碳原子的醇类和醛类是最有活性的化合物.2)大豆蚜和棉蚜对醛类和脂类的反应要比对相应的醇类强,这与桃蚜的实验结果刚好相反.3)蚜虫嗅觉系统所显示的活性与刺激化合物的结构有关,醇类和醛类刺激所引起的EAG饱和的要比不饱和的强.4)大豆春迁蚜对萜烯衍生物(醇、醛、脂)的触角电位反应高于棉蚜,而对萜烃化合物的反应刚好相反.5)各种化合物引起的EAG峰形不同;牛儿醇、癸醇和香茅醇刺激所引起的波形回复最慢,而在直链饱和醇中随着碳原子数的增加而回复速度减慢.  相似文献   

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