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1.
Chrysochromulina quadrikonta (Prymnesiophyceae), a quadriflagellatespecies previously unrecorded in New Zealand, was isolated fromNelson Harbour, New Zealand, in autumn 1991. It bears unmineralizedplate and spine scales, which morphologically are most likethose of Chrysochromulina ericina. Chrysochromulina quadrikonta,Chrysochromulina camella (isolated from the Marlborough Sounds,New Zealand) and Chrysochromulina polylepis (an ichthyotoxicspecies originally isolated from Scandinavia) grew most rapidly(growth rates, or divisions per day, of 1.41, 1.49 and 1.43,respectively) when cultured in a seawater-based general-purposenutrient medium at a salinity of 24% and pH 7.9, with only C.camellastill growing at 42% Chrysochromulina quadrikonta and C.camellagrew optimally at 25°C. and C.polylepis between 15 and 20°C;only C.polylepis grew at 10°C. Chrysochromulina quadrikontagrew optimally with potassium nitrate and ammonium chlorideas nitrogen source, whereas C.camella and C.polylepis grew equallywell with urea as nitrogen source. Only C.quadrikonta and C.polylepishad a selenium requirement. Unlike C.polylepis, neither of theNew Zealand isolates was phagotrophic nor ichthyotoxic.  相似文献   

2.
通过测定赤眼蜂Trichogramma羧酸酯酶和乙酰胆碱酯酶的活性、对底物的亲和力以及对抑制剂的敏感度研究了繁殖寄主对松毛虫赤眼蜂T.dendrolimi和螟黄赤眼蜂T.chilonis的影响。柞蚕卵和米蛾卵繁殖的赤眼蜂羧酸酯酶对底物的亲和力有不同程度的影响,柞蚕卵繁殖的赤眼蜂羧酸酯酶对α-乙酸萘酯或β-乙酸萘酯的亲和力最高是米蛾卵的2倍以上。繁殖寄主对乙酰胆碱酯酶对底物亲和力没有明显的影响。米蛾卵繁殖的松毛虫赤眼蜂羧酸酯酶活性明显高于柞蚕卵繁殖的种群,而米蛾卵繁殖的螟黄赤眼蜂种群羧酸酯酶的活性明显低于柞蚕卵繁殖的种群。用柞蚕卵繁殖的松毛虫赤眼蜂种群对对氧磷的敏感度明显低于米蛾卵繁殖的种群,而增效磷则正好相反。繁殖寄主对松毛虫赤眼蜂吉林种群乙酰胆碱酯酶对DDVP和毒扁豆碱的敏感度没有明显的影响,而在松毛虫赤眼蜂广东种群和螟黄赤眼蜂中,柞蚕卵繁殖的种群乙酰胆碱酯酶对DDVP和毒扁豆碱的敏感度明显低于米蛾卵繁殖的种群。  相似文献   

3.
Changing distribution patterns of T. pisana and C. virgata atcoastal sites around South Australia suggest T. pisana is replacingC. virgata in some areas Under laboratory conditions C. virgata exhibits reduced survivaland growth, is less active and feeds less when kept in the presenceof T. pisana adults and/or their mucus and excrement. If thearea of cooccurrence is large relative to the population size,C. virgata may be displaced to the less favourable habitats.No inhibition of the fecundity of C. virgata was seen. Bothspecies also depress feeding intraspecifically T. pisana also preys on C. virgata under some conditions, notnecessarily when food is limiting It is suggested that these mechanisms act within co-occurringpopulations of the species and result in the exclusion of C.virgata from some areas *Present address: 9 Torrens Ave, West Hindmarsh, South Auustralia,5007 (Received 1 November 1986; accepted 15 November 1987)  相似文献   

4.
A cytokinin-nonrequiring strain (T22) was isolated from a cytokinin-requiringcallus strain T2 of tobacco (Nicotiana tabacum var. Bright Yellow). Strain T22 grew rapidly on the medium without added kinetinat 26?C. But its growth was completely suppressed at 16?C. Thisgrowth suppression at 16?C was partially recoverable by supplyingkinetin. Benzyladenine, geranylaminopurine and 2-methyl-8-benzylamino-s-triazolo[l,5-a]pyrazinewere also effective in removing growth suppression at 16?C.Adenine, which was unable to remove growth suppression of T22at 16?C, promoted the growth of T2 at 26?C, but not at 16?C.Physiological differences between cytokinin-requiring and -nonrequiringcalluses are discussed. 1Part II in the series "Studies, on Plant Tissue Cultures";for Part I, See Plant & Cell Physiol. 9: 103–114 (1968). (Received May 29, 1970; )  相似文献   

5.
The genus Tambja previously included 24 described species. Fournew species, T. tentaculata n. sp., T. gabrielae n. sp., T.zulu n. sp. and Tambja victoriae n. sp., from the Indo-Pacificare described. Tambja tentaculata n. sp., from Guam, is theonly known species in the genus with well developed, dorsolaterallygrooved, oral tentacles. Its inner lateral teeth have a bifidinner cusp with two long, sharp denticles. The oral tentaclesof T. tentaculata are more typical of Roboastra species, whilethe shape of the inner lateral teeth is more typical of Tambja.Nevertheless, the arrangement of the two cusps of the innerlateral teeth and the presence of a rachidian tooth withoutdenticles and with a central notch at the anterior edge, typicalof the species of the genus Tambja, suggest the placement withinthis genus. Tambja gabrielae n. sp., from Indonesia and PapuaNew Guinea, has dark green to dark brown ground colour withbright yellow patches scattered on the body. Tambja zulu n.sp. from Durban, South Africa, is characterized by a black groundcolour with slender yellow longitudinal lines. Tambja victoriaen. sp. is a new species from Papua New Guinea and Australiathat has frequently been misidentified as Roboastra arika, characterizedby its blue body colour and yellow lines. The four species aredistinguishable based on differences in body coloration, ofcharacters of the radula and of the reproductive system. Anoverview on distinguishing features of all known Indo-PacificTambja species is presented. (Received 21 June 2004; accepted 20 January 2005)  相似文献   

6.
SYNOPSIS. This paper develops a model based on egg-laying ratesand female oviposition temperature preferences in two speciesof cicada, Cacama valvata and Tibicen bifidus, from a centralNew Mexico desert grassland habitat. Output from the model indicatesthat C. valvata achieves maximal daily egg production (eggsfemale–1 day–1) on days when maximum shade ambienttemperatures reach 41°C; the corresponding value for T.bifidus is 33°C. These differences correlate with the thermalregime experienced by each species in its respective typicalhabitat. Simulations of the effects of variation in mean habitatambient temperature on egg production demonstrated that knowndistributional limits for T. bifidus correspond to thermal conditionsthat reduce daily egg production by only about 5–10% relativeto long-term means at the study site. The same is true for C.valvata only in lower-ambient temperature habitats. In higher-temperaturehabitats, C. valvata exhibits an unusual plasticity in the timingof adult activity and reproduction that allows it to occupya much wider geographic range than T. bifidus. Contrary to expectations,frequency distributions of predicted daily egg production rateswere negatively skewed in each species' respective ‘typicalhabitat’, and Gaussian only in thermally marginal habitats.The findings are discussed in the context of attempts to modelpopulation- and community-level effects of climatic change.  相似文献   

7.
水菖蒲活性物质β-细辛醚对四种储粮害虫的熏蒸活性   总被引:2,自引:0,他引:2  
植物性次生物质在植物-害虫的关系中起着非常重要的作用, 植物中的一些成分对害虫具有熏蒸、触杀和驱避等作用。水菖蒲Acorus calamus L.是一种常用中药, 它的主要杀虫活性成分为β-细辛醚。本研究通过室内生测试验研究了水菖蒲根茎提取物β-细辛醚对玉米象Sitophilus zeamais Motschulsky、谷蠹Rhyzopertha dominica (Fabricius)、赤拟谷盗Tribolium castaneum (Herbst)和四纹豆象Callosobruchus maculatus (Fabricius) 4种储粮害虫的熏蒸击倒和致死作用。结果表明: β-细辛醚对4种试虫的熏蒸击倒和致死作用明显。以50 μL/L的浓度处理120 h后, 对玉米象、谷蠹和四纹豆象的击倒作用均达到100%, 而对赤拟谷盗击倒率为50%; 玉米象、谷蠹和四纹豆象的死亡率分别为81.23%, 97.78%和100%, 而赤拟谷盗死亡率仅为8.89%。处理24 h, β-细辛醚对玉米象、谷蠹、赤拟谷盗和四纹豆象的KC50分别为49.38, 102.96, 124.04和1.07 μL/L; 处理120 h, β-细辛醚对玉米象、谷蠹、赤拟谷盗和四纹豆象的LC50分别为17.82, 4.42, 116.48和0.73 μL/L。结果显示水菖蒲根茎提取物β-细辛醚对4种储粮害虫均具有明显的熏蒸效果, 具有开发为储粮害虫熏蒸剂的潜力。  相似文献   

8.
In south-eastern France, Trochoidea geyeri (Soós) todaycharacterizes open upland environments from about 1000 m abovesea level. At lower altitude it is replaced by Candidula unifasciata(Poiret)—another member of the Helicellinae—whilethe other members of the community remain almost the same. Duringthe cold stages of the Quaternary, T. geyeri was also an importantelement of lowland gastropod communities in Provence, whileit was always replaced by C. unifasciata during the interglacialstages. Thus, T. geyeri seems to be a valuable cold indicatorspecies for palaeoclimatic reconstructions. Some anomalies in this pattern, however, show that each of thesespecies can live in bioclimatic conditions which characterizethe area of the other. This suggests a competitive dominancephenomenon from a threshold situated around 1000 m on the altitudinalgradient. The influence of competitive interaction is demonstratedusing similar altitudinal gradients in which T. geyeri is missingbecause of historical factors: in such cases, C. unifasciataoccupies the entire gradient, up to 2250 m. Quaternary climaticchanges produced altitudinal shifts of the contact zone betweenT. geyeri and C. unifasciata, and, correlatively, repeated isolationsof T. geyeri populations. (Received 26 December 1992; accepted 4 February 1993)  相似文献   

9.
A new genus of Assimineidae, Conassiminea, is described fromestuarine habitats in southeastern Australia (New South Wales,Tasmania and Victoria). Two new species, C. studderti and C.zheni, are included in the genus, the former being the typespecies. Conassiminea is distinct from all other assimineidgenera in two autapomorphies in the female reproductive system:the seminal receptacle has two ducts and the bursal duct isextremely wide. The phylogenetic relationships of the new genuswere examined using a morphological dataset. (Received 26 February 2005; accepted 22 April 2005)  相似文献   

10.
The intertimdal gastropod Thais malayensis n.sp. (Neogastropoda,Muncidae) is described from Singapore and peninsular Malaysia.Although a common species, it may have been previously overlookedor mistaken for other species found in and near mangroves. Anotherpoorly known species, T javanica (Phdippi) may also have beenconfounded with the new species. New data on their soft parts,radulae, opercula, and egg capsule morphology are presentedto distinguish between these closely related species. (Received 26 February 1996; accepted 15 May 1996)  相似文献   

11.
Seven new species of the nudibranch genus Trapania Pruvot-Fol,1931 (Goniodorididae) are described from the Indo-West Pacificand an eighth species, T. japonica (Baba, 1935), originallydescribed from one preserved specimen from Japan, is redescribedfrom specimens collected in Hong Kong and tropical eastern Australia.Three of the new species are from temperate south-eastern Australiaand one from tropical eastern Australia. Two species are knownonly from Hong Kong and a third is recorded from the SudaneseRed Sea as well as Hong Kong. Only ten other species of Trapania have been described, sixof those from Europe, and one each from Brazil, California,Japan and New Zealand. The anatomy and external colour patternof these species is compared with that of the seven new species. (Received 12 December 1986;  相似文献   

12.
The genus Tricolia(Phasianellidae) in the Eastern Atlantic andMediterranean is reviewed on the bases of radular morphology,shell characters and polychromatism. The taxa included within the T. pullus (L.) group are not clearlyseparable and are treated as geographical subspecies:T. pulluspullus (L.), T. pullus picta (da Costa), T. pullus azorica (Dautzenberg),T. pullus canarica Nordsieck. The case of T. tenuis (Michaud)is problematic since it is clearly separable from sympatricT. pullus pullus in most parts of the Mediterranean but transitionalto T. pullus picta, towards the Atlantic. Other taxa are considered as having specific status since theyare consistently separable when found in sympatric populations.These include T. speciosa (Muhlfeldt), T. miniata (Monterosato),T. tingitana n.sp., T. petiti (Craven), T. nordsiecki (Talavera)and T. algoidea (Pallary). The last two species are stated forthe first time as belonging to the Phasianellidae. The genusEpheriella Pallary, based on T. algoidea, is synonymized withTricolia. (Received 6 April 1981;  相似文献   

13.
The New Zealand Pulmonate fauna contains 22 naturalized terrestrialspecies. For each, a bibliography is given for the New Zealandliterature and comment made on its biology and distribution.Vertigo ovata SAY and Oxychilus draparnaldi (BECK) are newlyrecorded from New Zealand. (Received 11 February 1981;  相似文献   

14.
15.
The effect of UV-B radiation on the vertical distribution ofthree calanoid copepod species (Tortanus dextrilobatus, Acartiuraspp. and Acanthacartia spp.) and three larval stages of Pacificherring, Clupea pallasi (1-, 7-, and 14-day-old larvae) wasinvestigated. A series of 2 m high columnar tanks equipped withinfra-red light and video-microscopy was used to investigatethe vertical distribution of zooplankton in the presence andabsence of UV-B radiation. In the presence of UV-B radiation,T.dextrilobatus and 1-day-old C.pallasi resided about 50 cmdeeper than in the absence of UV-B, while Acartiura spp. andAcanthacartia spp. showed no (or only minimal) change in verticaldistribution. Mortality experiments were also conducted outdoorsin which each copepod species was exposed to full or reducednatural radiation levels. Only T.dextrilobatus showed an increasein mortality when exposed to full radiation. Our results showedthat T.dextrilobatus and 1-day-old C.pallasi larvae were sensitiveto UV radiation (UVR), and to reduce or eliminate UV-inducedstress, they avoided the surface of the water column when UV-Bradiation was present. Copepod species were chosen to span arange of pigmentation: T.dextrilobatus (heavily pigmented),Acartiura spp. (moderately pigmented) and Acanthacartia spp.(not pigmented). The pigmentation did not appear to play a rolein UVR tolerance of the copepods, but may be a factor determiningUV tolerance of C.pallasi.  相似文献   

16.
粘虫中肠α-淀粉酶活性测定方法的参数优化   总被引:1,自引:0,他引:1  
孔玉萍  黄青春  刘曼慧  丰俊  刘扬 《昆虫学报》2007,50(10):981-988
针对粘虫Mythimna separata中肠α-淀粉酶筛选了11种不同参数组合的3,5-二硝基水杨酸活性测定方法,并对其中最适组合的各个参数进行了优化。结果表明:在离体测定条件下,粘虫中肠α-淀粉酶活性的最优化测定参数为0.03 mol/L 磷酸盐缓冲液(pH 8.0,含有55 mmol/L NaCl)、温度45℃、吸收波长480 nm。Ca2+对α-淀粉酶活性具有抑制作用。该优化法能够显著降低粘虫、德国小蠊Blattella germanica、黄粉虫Tenebrio molitor、淡色库蚊Culex pipiens pallens和家蝇Musca domestica等昆虫α-淀粉酶的米氏常数Km值,且粘虫和德国小蠊α-淀粉酶的Vmax值增大,但黄粉虫、淡色库蚊和家蝇α-淀粉酶的Vmax值均明显减小。结果说明,在该优化体系下,粘虫α-淀粉酶与底物的亲和力增强,最大反应速度增大,测定酶活性的准确性和灵敏度显著提高;同时该优化体系也可作为测定德国小蠊α-淀粉酶活性的优化方法,但不适合作为黄粉虫、淡色库蚊和家蝇α-淀粉酶的最优化测定方法。  相似文献   

17.
Diurnal patterns of CO2 exchange and fluctuations of tissuemalic acid concentrations were investigated in three speciesof Commelinaceae: Callisia fragrans and Tripogandra multiflorafrom Jamaica, and Tradescantia brevifolia from southern Texas.Very low levels of CAM gas exchange were induced by droughtstress in C. fragrans and T. multiflora. In addition, past indicationsof CAM-cycling in the two Jamaican species were confirmed indrought-stressed plants; however, only C. fragrans exhibitedCAM-cycling under well-watered conditions. CAM-cycling underdrought stress was also found in T. brevifolia. This constitutesthe first report of CAM (sensu lato) in the genus Tradescantia.The importance of low-level CAM in these three species is discussedas a potential adaptation to drought.Copyright 1994, 1999 AcademicPress Callisia fragrans, Tradescantia brevifolia, Tripogandra multiflora, Commelinaceae, CO2 exchange, Crassulacean acid metabolism, CAM-cycling, CAM-idling, drought stress, malic acid fluctuations  相似文献   

18.
14CO2 assimilation was studied with diploid, tetraploid, hexaploidspecies of the genera Triticum and their wild relatives Aegilops.Attached mature leaves of 3–4 weekold plants were allowedto undergo photosynthesis under air at ambient temperature.The pattern of distribution of 14C was notably similar in Triticumand Aegilops species whatever the level of ploidy. Sucrose wasthe sink for photosynthetic carbon. 14C for sucrose synthesis was supplied either through the glycolatepathway by glycolate, the product of the photorespiration orby the Calvin cycle intermediates exported into the cytoplasm.Depending on the species, the glycolate pathway provided 40to 75%of the sucrose 14C. The higher labeling of sucrose was associated with the greaterparticipation of the glycolate pathway in the wild diploid (DD)A. squarrosa and in the cultivated hexaploid (AABBDD) T. aestivum.The results suggest that the expression of the male D genomeis dominant over the female AB genome in T. aestivum. In T. aestivum under ambient conditions lowering (low temperature)or hindering (1% O2 ) photorespiration, sucrose labeling decreased,but serine and glycine labeling was favoured. We propose thatin wheat leaves, the role of photorespiration is to drain artof the carbon exported from the chloroplast as glycolate, towardssucrose synthesis. (Received March 16, 1979; )  相似文献   

19.
20.
HEPPER  C. M. 《Annals of botany》1978,42(1):109-115
Five to 7 per cent of plants of Trifolium repens L. and T.pratenseL. and 100 per cent of plants of T. subterraneum L. were nodulatedby Rhizobium leguminosarum but none of T. hybridum L., T. glomeratumL. or T parvifirum Ehrh. The frequency of nodulation of T. pratenseby R. leguminosarum was much increased by breeding from susceptibleplants. Such plants were not nodulated by bacteria isolatedfrom any other cross-inoculation group, but remained fully susceptibleto R. trifolii. The nodules formed by R. leguminosarum are generallyassociated with lateral roots and are ineffective.  相似文献   

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