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1.
Chaffey  Nigel 《Annals of botany》2005,95(7):1253-1254
Over 40 years ago, in what is surelyone of the most famous ‘throw-away lines’ in botany,Ledbetter and Porter (1963) suggested that the similar orientationsof cytoplasmic microtubules and structures considered to becellulose microfibrils in the cell wall was not coincidental.This notion led almost single-handedly to the present and enduringinterest amongst certain plant cell biologists in understandingthe role of microtubules in wall formation. And as a resultof this intense interest in such matters, it has become clearthat microtubules are not only ‘just one’ componentamongst an ever-expanding array of  相似文献   

2.
Googling the term‘molecular ecotoxicology’ results in less than 1000hits compared to more than 8·5 million for ‘moleculargenetics’. Hence, we are dealing with a rather new orless well-defined and less propagated field of science. Springer'sbook Molecular ecotoxicology of plants edited by H. Sandermannmay therefore fill a gap and it is unique in focusing on plants.A first introductory chapter sets the stage and tries to definethe term for a broad  相似文献   

3.

Few areas of science have progressed as rapidly, or have hadsuch an impact on public consciousness and governments, as recentadvances in plant biotechnology. These exciting scientific discoveriesand their increasing application are continuing to generateconsiderable economic, social and ethical considerations. Particularconcerns have been expressed, however, about potential ‘foodsafety’ and ‘environmental impact’ implications,in particular, of this ‘revolution in biology’ inagriculture and the food  相似文献   

4.
PAROLIN  PIA 《Annals of botany》2005,95(6):1067-1068
‘Delight’ said CharlesDarwin in his diaries in 1832, ‘is a weak term to expressthe feelings of a naturalist who, for the first time, has wanderedby himself in a Brazilian forest’. These feelings musthave been those which drove Margaret Mee to explore the Brazilianjungles on numerous expeditions between 1958 and 1964, creatingwonderful pictures despite all kinds of difficulties encounteredin this hostile world. And these feelings were also those Ihad when I read this book: delight about her precise drawingsand life-like paintings, which are extremely expressive from  相似文献   

5.
Changes in the major alcohol-soluble, low molecular weight carbohydratesof P. purpurea, O--D-galactopyranosyl-(1-2)-glycerol (‘floridoside’)and O--D-galactopyranosyl-(1-1)-glycerol (‘isofloridoside’),have been examined in response to salinity variation. ‘Floridoside’is shown to vary in absolute amount, increasing in hypersalineand decreasing in hyposaline media. ‘Isofloridoside’content per cell does not change in a similar manner. Responsesare almost identical under light or dark conditions, ‘floridoside’changes being complete within 24 h. Decreasing the externalwater potential using ionic and non-ionic solutes has the sameeffect upon galactosyl-glycerol content. The amount of ‘floridoside’synthesized, and degraded under hypersaline and hyposaline conditionsrespectively is shown to be insufficient to restore cell volumeto its original value. It is therefore suggested that the primaryfunction of ‘floridoside’ increases in concentratedsea-waters is that of a compatible solute, serving to protectthe cell during periods when the external salt content is increaseddramatically.  相似文献   

6.
This book has beenwritten primarily as a text for a senior plant anatomy course.The initial phrase ‘An introduction to’ is somewhatmisleading as a student would need to have some elementary knowledgeof botany as well as cell structure and physiology to followthe information and the ideas without difficulty. The authordoes  相似文献   

7.
Plant nutritionis ultimately an applied subject that seeks to understand theprocesses and mechanisms that underpin the uptake, assimilationand internal redistribution of nutrients by plants and thento use this information to improve the yield or quality of harvestedplant parts, be they grains, storage roots or leafy vegetables.The subject now also encompasses the understanding of the responsesof plants to nutrient toxicities (e.g. salinity) as well asnew topics such as metal ‘hyperaccumulation’ and  相似文献   

8.
Smith  F. Andrew 《Annals of botany》2007,100(1):151-152
It is (or should be) self-evident that life on Earth dependsmainly on life in earth, and in this respect soil–plantinteractions are of key importance. This book brings togetherareas that are still often compartmented into fields such aschemical and physical aspects of soil science (where plantsare still sometimes regarded as a ‘black box’ ofuncertain relevance), plant physiology (now sometimes re-badgedas plant functional biology), and soil microbial ecology. Agriculturalscientists have, of course, rarely been guilty of ignoring soilfactors in relation to plant growth and productivity. Plantecologists sometimes have, and to some of them it's the soilthat is the ‘black box’ when it comes to understandingplant population and community ecology. Models of the  相似文献   

9.
ERRATA     
Page 806, Preparation of Mitochondrial Fraction, line 4: The following should be inserted between ‘centrifugedat’ and ‘20 000 g for’: 3000 for 10 mm. Thesupernatant was centrifuged at The following corrections are required: Page 104, line 20: ‘2-hydroxylation’ should read ‘2-ß3-hydroxylation’ Page 106, line 11: ‘of Ga8’ should read ‘to GA8’ Page 113, last line:‘length 50 µm’ shouldread ‘length 150 µm’ Formula 15 should read: Formula 17 should read: y(0)– y* = ß1V12V2 page 118: Formula 18 should read: Formula 23 should read: Formula 24 should read:   相似文献   

10.
This book (a translation fromSchulze et al., 2002) is one of the most comprehensive textbooksof plant ecology so far. The authors aim to ‘for the firsttime bring together and clearly organize the large subdisciplinesof plant ecology’ and, to a large extent they have succeeded.The book is well written, and its more than 500 illustrationsare beautifully laid out and well chosen to help the readerunderstand the theory. It is clearly suitable not only  相似文献   

11.
The motto of the PhotosynthesisCongress in Brisbane in 2001 was that ‘photosynthesissimply sustains all life on Earth’. For this reason, photosynthesisis a large, well-researched area, so it is especially ambitiousto put together a handbook that attempts to cover the wholesubject. This volume is definitely not a handbook in the sensethat it provides a compendium for the novice, but instead itis a conspectus of areas of  相似文献   

12.
Extracts of small and mature-size lupin pods yielded four substancesaffecting the growth of wheat-coleoptile sections: one acidpromotor (A), two acid inhibitors(B and X), and one neutralinhibitor(Y). Inhibitor B was extremely active, however, coleoptile sectionsshowed no signs of toxic effects; they resumed growth at a rapidrate after rinsing them and adding ß-indolylaceticand (IAA) to the medium. 1 µg of IAA was required to counteractthe effect of ‘B’ extracted from 230 mg. Of tissue.On an equal fresh weight basis the inhibiting action of ‘B’in lupin pods was 500–1,500 times more potent than thatof ‘inhibitor ß’ in etiolated pea seedlings. Small pods of plants infected with pea-mosaic virus yielded3 times the amount of ‘A’ of healthy plants (equivalentto 1 µg. IAA 0.3 µg. IAA per 25 g. of tissue respectively),and approximately the amount of ‘B’. Mature podsof virus-infected plants again yielded more‘A’,but also 2? times more ‘B’ than pods of healthyplants. Healthy pods yielded more ‘A’ than virus-infectedpods, and there was no difference in ‘X’. A lupin abscission test was developed and the effects of proximaland distal application of -naphthyl acetic acid (NAA) are presented,and discussed with respect to results of other abscission tests. ‘A’ accelerated abscission when applied proximally,and delayed or prevented it when applied distally. ‘B’strongly accelerated abscission when applied in either way.A possible mechanism explaining the abscission-inducing effectof developing pods on later flowers is discussed in terms ofthe substances ‘A’ and ‘B’. The partlyprevented abscission observed on virus-infected plants was foundto agree well with the proposed mechanism.  相似文献   

13.
14.
This book is the 11th volume inthe series ‘Annual Plant Reviews’, which is dedicatedto summarizing the most recent achievements in specific fieldsof plant biology. The volume comprises nine different thematicchapters, each written by distinguished experts  相似文献   

15.
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17.
This book is a collection of papersfrom the major researchers involved in physiological, molecularand genomic research on bryophytes, mainly, although not exclusively,using the moss Physcomitrella patens. This is a growing areaof research and the book aims to provide ‘... a synopsisof the outstanding basic research being conducted using mossesas a model multi-cellular eukaryote’. Bryophytes (mosses, liverworts and hornworts) are an importantand often neglected group  相似文献   

18.
RICKETTS  T. R. 《Annals of botany》1988,61(4):451-458
When nitrate, ammonium, or urea were the sole nitrogen sourcesfor the growth of Platymonas striata there was a short initiallag period, after which uptake/assimilation occurred at a constantrate. Glycine ‘uptake’ was however non-linear withtime. Addition of ammonium or urea markedly inhibited nitrate‘uptake’ whereas although glycine was initiallytotally inhibitory, nitrate ‘uptake’ recommencedabout 1 h after addition, but at a greatly reduced rate. Ammoniumtotally inhibited urea ‘uptake’, but did not inhibitglycine ‘uptake’. When ammonium, urea, or glycinewere present at the same time as nitrate the total rate of nitrogen'uptake/assimilation was within 40% (or closer) of that of nitratenitrogen ‘uptake’ alone. In the first two casesthis reflected a total switching off of nitrate ‘uptake’whilst the new substrate was assimilated at a rate similar tothe initial nitrate rate, whereas in the case of glycine, bothsubstrates were used simultaneously. Once the concentrationof any of the inhibitory nitrogen sources had been reduced toa low level the ‘uptake’/assimilation of nitraterecommenced. It is suggested that the ability of P. striatato maintain a more or less constant rate total nitrogen ‘uptake’/assimilationirrespective of the mixture of utilizable nitrogen sources presentedto it, is not due to controls at the level of the entry of substrateinto the cell, but to intracellular actions at the enzyme level.The relative constancy of, and high rate of ‘uptake’,irrespective of nitrogen source and over a wide range of extracellularconcentrations, is tentatively considered to be due to saturationof the assimilatory mechanisms under the conditions employed;all the sources lead, either directly or indirectly, to theproduction of amino groupings for entry into nitrogenous metabolism.This homeostasis of nitrogen ‘uptake’/assimilationwould clearly be of considerable benefit to the alga in nature,enabling it to maximize growth in changing environmental conditions. Platymonas striata, nitrogen update, nitrogen assimilation  相似文献   

19.
Editorial     
The first 150 words of the full text of this article appear below. THE RICH DIVERSITY OF GENOMICS—A REPORT ON THE ‘COMPARATIVE AND FUNCTIONAL GENOMICS (BITS) WORKSHOP’, HINXTON, UK, 27–30 OCTOBER 2005 The Comparative and Functional Genomics (BITS) Workshop hasa history that in many ways reflects the changing face of moderngenomics. Started 15 years ago under the banner of ‘Identificationof the Transcribed Sequence’, the meeting was designedto bring together leading researchers from around the worldwho were pioneering new global approaches to gene discoveryin a small workshop setting. As more and more transcribed sequencesbecame known, the emphasis of the meeting, like the communityit served, focused on how to characterize the function of allthe newly acquired genes. A decision was therefore made to changeits name to ‘Beyond the Identification of the TranscribedSequence Workshop’, or BITS for short. As the years havepassed the meeting has continued to diversify and change (ashas its name), but it has continued to attract scientists tothe cutting edge of genomics research. At this year's meeting,hosted . . . [Full Text of this Article]  相似文献   

20.
Cellulose Microfibril Orientation in Rubbery Wood   总被引:1,自引:0,他引:1  
The fibre length L and average helical angle of microfibrilorientation in fibres from successive growth rings in both normaland ‘rubbery’ wood of stems of apple var. Lord Lambournehave been measured. It has been shown that the normal relationship,L = A+B cot , does not hold for ‘rubbery wood’.There is a tendency for the helix to remain flat, the angle fairly constant independently of fibre length. This, togetherwith abnormalities in the lignin chemistry, causes the rubberywood to have low tensile strength and high extensibility.  相似文献   

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