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1.
Some effects of artificial mixing on the dynamics of phytoplankton populations in large limnetic enclosures 总被引:14,自引:0,他引:14
Reynolds C.S.; Wiseman S.W.; Godfrey B.M.; Butterwick C. 《Journal of plankton research》1983,5(2):203-234
Effects of a series of artificial mixings of part of the watercolumn of a limnetic enclosure (Lund Tube C, BlelhamTarn, Cumbria) upon the rates of net change in the standingpopulations of selected species of phytoplankton are described.Increase of Sphaerocystis and Anabaena was relatively fasterunder the quiescent, stratified conditions ofunmixed columns whereas mixing generally favoured the net increaseof diatoms (e.g., Fragilaria) or, at times, of Oscillatoria.The sequences corresponded closely to supposed successionalpathways, which are thus suggested to be naturally regulatedby seasonally-changing physical characteristics of the watercolumn. Performance characteristics of the mixing apparatusand a mathematical expression of the net rate of change in naturalFragilaria populations are appended. 相似文献
2.
《Journal of experimental botany》1977,28(6):1247
Effects of coupled solute and water flow in plant roots withspecial reference to Brouwer's experiment. Edwin L. Fiscus. p. 71 Abstract: Line 3 delete interval insertinternal. p. 73 Materials and Methods: line 6: delete diversion insert division line 9 equation should read Jv=Lp PRT(C0C1). 74 Last line of figure legend: 101 should read 1011. 75 Line 11: delete seems insert seem. le 1 column heading106 should read 1011. 77 delete ...membrane in series of... insert membranein series or... Delete final paragraph. 相似文献
3.
《Journal of Molluscan Studies》1953,29(6):258
Part 1, under the frontispiece portrait of Dr. N. B. Eales,the words President 19481951 should havebeen added. Page 103, line 49, for Newton Collection readNorman Collection (Canon Norman). 185, line 37, for capillaris read capillacca. 188, Table 1, for bemoralis. read nemoralis. 188, Table 2, for Cochlicella acuta (Müll)? ventrosa(Fér.) read Cochlicella ventrosa (Fér.). 191, line 24, for araheo- read archeo-. 相似文献
4.
In nodulated common bean (Phaseolus vulgaris L.), there is typicallya period of N stress between 15 and 20 d after emergence (DAE),due to a lack of synchronization between the depletion of Nin the cotyledons and the beginning of N2 fixation and transport.Screening trials identified some Rhizobium leguminosarum bv.phaseoli strains with which symptoms of N deficiency were notvisible (precocious strains). Cultivar Negro Argelwas then inoculated with two traditional strains(C-05 and CIAT 727) and two precocious strains(CNPAF 146 and CNPAF 512), and plants were harvested from 8to 30 DAE. There were no differences between the two groupsof strains in nodule dry weight or in the acetylene reductionrates between 8 and 16 DAE. However, nodules induced by theprecocious strains showed earlier onset of glutaminesynthetase (GS) (EC 6.3.1.2
[EC]
) and glutamate synthase (GOGAT)(EC 1.4.1.14
[EC]
) activities, and ureide synthesis. The N concentrationin the nodules formed by precocious strains variedfrom 4.2 to 4.5%, whereas with the traditionalstrains, it increased from 3.2% at 8 DAE to 65% at 18 DAE, atwhich time plants exhibited N-deficiency symptoms. By 21 DAE,GS and GOGAT activities in traditional noduleswere increased, as well as the ureide-N-concentration in thexylem sap, nodule N content declined to 4.5% and the leavesbecame green. These results suggest that the N stress with traditionalstrains is not a limitation in early N2 fixation activity butrather in the rates of expression of the processes of N assimilationand transport. Key words: Glutamate synthase, glutamine synthetase, nitrogen fixation, Phaseolus vulgaris, Rhizobium 相似文献
5.
Primary and Secondary Induction Requirements for Flowering of Contrasting European Varieties of Lolium perenne 总被引:1,自引:0,他引:1
The flowering requirements of six European varieties of Loliumperenne L. were studied in controlled environments. In experimentson primary induction, flowering was recorded after transferto long days (LD) in a greenhouse at 1224°C. In experimentson secondary induction, primary induction was first accomplishedat 6°C/10 h daylength for 12 weeks. When evaluated by the50% heading criterion, the requirement for duration of primaryinduction at 6°C/8 h daylength was <3 weeks in Mediterranean,56 weeks in Central European and 78 weeks in Scandinavianvarieties. While Veyo (Italy) flowered profuselyregardless of temperature or daylength during primary induction,critical temperatures for primary induction in SD and LD were15 and 11°C in Baca (Czech Republic) and 11and 7°C in Falster (Denmark). The criticalphotoperiod for secondary induction at 15°C ranged from12 h in Veyo and 14 h in Baca to16.5 h in Falster and 17.5 in Kleppe(Norway). The critical number of LD cycles varied correspondingly.While the Central and North European varieties required fewerLD cycles for 50% heading at 18 than at 12°C, Veyoshowed the opposite response. It is concluded that the requirementsfor both primary and secondary induction of Lolium perenne increasewith increasing latitude of origin of the germplasm. In oneexperiment, 3987% of the inflorescences came from tillersthat were not visible on transfer from primary to secondaryinduction, thus it is also concluded that there is no juvenilestage in tillers of Lolium perenne. Copyright 2000 Annals ofBotany Company Daylength, flowering, juvenility, perennial ryegrass (Lolium perenne L.), primary induction, secondary induction, temperature, varieties, vernalization 相似文献
6.
SINGH N; SINGH S N; SRIVASTAVA K; YUNUS M; AHMAD K. J; SHARMA S C.; SHARGA A N 《Annals of botany》1990,65(1):41-44
Five Gladiolus cultivars, namely Aldebaran, BrightEye, Illusion, Manisha andManmohan, were exposed to 1 and 2 µg l1sulphur dioxide to test their relative-sensitivity toleranceto the pollutant Plants were fumigated experimentally for 2h daily Foliar injury symptoms were observed first in Manishafollowed by Aldebaran and Illusionat the higher dose Photosynthetic pigments and leaf extractpH were significantly decreased, particularly in Manishaand Illusion Overall disturbances in the plantmetabolism due to SO2 treatment led to retarded growth of plants,as evident from decreased shoot length and phytomass valuesThe order of sensitivity of the five Gladiolus cultivars toSO2 was as follows, with the greatest first Manisha, Illusion,Aldebaran, Bright Eye, Manmohan Cultivars, Gladiolus, sensitivity, sulphur dioxide, tolerance 相似文献
7.
The Nitrogen Content of Plants and the Self-thinning Rule of Plant Ecology: A Test of the Core-skin Hypothesis 总被引:3,自引:0,他引:3
The core-skin hypothesis postulates that secondarilythickened plants behave energetically as an inert corecovered by an active skin, the skinbeing two-imensional, the core three-dimensional.This would explain the self-thinning or3/2 rule of plant ecology, that is, the tendencyfor log (dry weight per plant) and log (number of plants perunit area) to progress along a straight line relationship, withslope = 3/2. The hypothesis was tested as follows. Plant nitrogen contentwas used as an estimate of the mass of skin perplant, and dry weight as an estimate of the mass of the core.As plants mature the slope of the relationship between y = log(mass of nitrogen per plant) and x = log (mass of dry matterper plant) is expected to decline from an initial value of 1.0towards a final value of 0.66. The intercept of the relationshipis expected to reflect the intrinsic content of skinper unit of core. Genotypic variation in thisparameter should cause genotypic differences in the maximumattainable yield of biomass per unit area. The expectations were investigated by fitting the function y= p+qx+r exp x to 30 sets of data on plant nitrogencontent, plant weight and time in 18 different vegetables. Simplelinear regressions of y on x were fitted to more limited setsof data on weights and nitrogen contents of mature trees. Theexpectations were, with some minor exceptions, confirmed. Nitrogen, yield, plant competition, self-thinning 相似文献
8.
The Importance of Light Intensity for Pollen Tube Growth and Embryo Survival in Wheat x Maize Crosses 总被引:1,自引:0,他引:1
The success of Triticum aestivumxZea mays crosses, used to producewheat doubled haploids, is influenced by light intensity. Toexamine the basis for this response, pollen tube growth, embryosurvival and indicators of photosynthetic rate were measuredin two wheat cultivars (Karamu and Kotuku)crossed with maize at two irradiance levels (250 or 750 µmolm-2s-1, PAR). Pollen tube growth was significantly affectedby light intensity in Karamu plants but not inKotuku plants, despite both cultivars being pollinatedby the same maize source. The percentage of pollen tubes reachingthe cavity between the ovarian wall and integuments, or in themicropyle of Karamu plants at high light intensity(65%) was nearly three-times greater than that at low lightintensity (22%). Thus, either low light intensity can affectthe maternal wheat plant in a way that inhibits pollen tubegrowth and/or high light intensity may promote pollen tube growthin Karamu plants. Significant differences in ratesof electron transport in plants grown at the two light intensitiesindicated that the rate of photosynthesis may also have an effecton pollen tube growth. These results have importance for improvingthe efficiency of wheat x maize crosses and other wide cerealcrosses. Copyright 2001 Annals of Botany Company Intergeneric hybridization, light intensity, pollen tube growth, embryo survival, Triticum aestivum, wheat,Zea mays , maize 相似文献
9.
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 Bin lupin pods was 5001,500 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 moreA,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. Bstrongly 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
10.
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 nitrateuptake 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 uptakewhilst 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
11.
The copepods Calanus australis and Calanoides carinatus developedfrom egg to adult in 20.3 and 18.3 days respectively at 15.5?Cand 16.0 and 12.0 days at 19.5?C. For both species the durationof the first two naupliar stages was short, <1 day. The thirdnaupliar stage was prolonged in C.australis but short in C.carinatus. Isochronal development was approximated from fourthnauplius through third copepodite; fourth and fifth copepoditestages were relatively long. Only female C.australis were produced;60% of the C.carinatus were female. Equiproportional developmentwas found for C.carinatus but not for C.australis. For bothspecies the variance in stage duration was established at thethird nauplius then remained unchanged through the older stages.In calculating developmental rates several commonly used methodswere compared. The method of first appearance of an individualof a given stage and mean time of appearance ofa stage both yielded estimates of development time thatwere 1015% faster than the more commonly used methodof median development time. We suggest that allfuture work on developmental rates of copepods should use astandardized method for the calculation of stage-specific developmentalrates and that median development time be themethod of choice.
3Present address: Marine Sciences Research Center, SUNY, StonyBrook, NY 11794-5000, USA 相似文献
12.
Mitochondria from 1-day-old bean cotyledons were isolated bya slow isolation procedure involving a wash andby a rapid procedure. The mitochondria isolatedby the rapid procedure were more tightly coupledthan those isolated by the slow procedure. Anexogenous supply of cytochrome c or NAD was shown to improvethe activity of mitochondria isolated by the slowprocedure, but not those isolated by the rapidprocedure. The phosphorylative abilities of the latter weremuch greater than the former and were retained for longer periods.It was found that there was a leakage of NAD out of the mitochondria. 相似文献
13.
Mycorrhizal Response of Two Tomato Genotypes Relates to their Ability to Acquire and Utilize Phosphorus 总被引:3,自引:0,他引:3
The purpose of this study was to determine how a plant's responseto colonization by mycorrhizal fungi relates to its abilityto acquire and utilize phosphorus for growth and reproduction.Two tomato genotypes previously found to be either responsive(LA1709) or unresponsive (large cherry)to mycorrhizal colonization during early vegetative growth wereexamined in detail. Plants were grown at four levels of addedphosphate or with mycorrhizal inoculum. Vegetative and reproductivegrowth, phosphorus uptake and root length density were measuredduring the course of plant development. Mycorrhizal symbiosissignificantly increased above-ground dry mass, root length,phosphorus content and yield under low phosphorus conditionsin LA1709, while it had less effect on these characteristicsin large cherry. When uninfected, however, LA1709grew and reproduced poorly unless high amounts of phosphoruswere added to the soil, while large cherry grewwell under very low phosphorus conditions. This was becauselarge cherry had significantly higher root lengthdensities than LA1709, enabling plants from thisgenotype to explore more soil volume and acquire greater amountsof phosphorus when grown without mycorrhizal fungi in low phosphorussoil. Large cherry also had higher phosphorususe efficiency and allocated a greater proportion of phosphorusto reproduction when uninfected than LA1709. Itappears traits that affect a plant's ability to acquire andutilize phosphorus efficiently for growth and reproduction canalso affect its response to mycorrhizal colonization in tomato.Copyright1998 Annals of Botany Company. Tomato,Lycopersicon esculentum,mycorrhiza,Glomus etunicatum,phosphorus, reproduction, lifespan. 相似文献
14.
The metabolic fate of [U-14C]sucrose in suspension culturesof Catharanthus roseus cells was monitored for 96 h after thecells were transferred to fresh complete (+Pi)or to phosphate-deficient Murashige and Skoog (Pi)medium. Sucrose was hydrolysed extracellularly to glucose andfructose. The rate of uptake of sugars by the cells was 1.53times higher in +Pi culture than in Piculture. Little difference in the rate of incorporation of radioactivityinto the ethanol-soluble fraction was found between the +Piand Pi cultures during the initial 24h of culture, but after 48 h the rate in +Picultures was higher than that in Pi cultures.Incorporation of radioactivity into ethanol-insoluble macromoleculeswas always significantly higher in the cells in +Picultures than in those in Pi cultures.The results suggest that Pi strongly affects the utilizationof sugars by cultured plant cells through the stimulation oftransport of sugars as well as through the activation of metabolism. Catharanthus roseus, Madagascar periwinkle, suspension culture, inorganic phosphate, sucrose, transport, metabolism 相似文献
15.
《Journal of Molluscan Studies》1965,36(6):323
WARBURG, M. R., 1965. On the water economy of some Australianland snails. Proc. malac. Soc. Lond. 36, 297305. Page 298: second line from bottom, should read within± 1 µg for Themapupa. Page 300: Fig. 2 legend, should read Evaporative waterloss from Sinumelon remissum (a), Pleuroxia sp. (b) and Themapupaadelaidae (c). Page 300: section 4 heading, should read Continuous curvesfor water loss. Page 301: second line, for Fig. 9 read Fig.3. Page 301: Table 1, last line, for 0.120024 read0.12024. Present address: Israel Institute for Biological Research, Ness-Ziona,Israel. 相似文献
16.
Angioy Anna M.; Barbarossa Iole Tomassini; Liscia Anna; Usai Maria L.; Orru Sergio; Muroni Patrizia; Crnjar Roberto 《Chemical senses》1990,15(2):145-150
Stimulation of single largest or marginallabellar chemosensilla can evoke ipsi- and contralateral labellarlobe spreading responses in Protophormia. Measurements of reflexlatencies indicate that the response is triggered by messagescoming from the largest ipsilateral chemosensilla.Input from the marginal chemosensilla would playa role in maintaining the already triggered response. 相似文献
17.
Developmental control of xylem hydraulic resistances and vulnerability to embolism in Fraxinus excelsior L.: impacts on water relations 总被引:3,自引:0,他引:3
Welbaum G.E.; Bian D.; Hill D.R.; Grayson R.L.; Gunatilaka M.K. 《Journal of experimental botany》1997,48(3):655-663
The freezing tolerance of many plants, such as pea (Pisum sativum),is increased by exposure to low temperature or abscisic acidtreatment, although the physiological basis of this phenomenonis poorly understood. The freezing tolerance of pea shoot tips,root tips, and epicotyl tissue was tested after cold acclimationat 2C, dehydration/rehydration, applications of 104M abscisic acid (ABA), and deacclimation at 25C. Tests wereconducted using the cultivar Alaska, an ABA-deficientmutant wil, and its wildtype. Freezinginjury was determined graphically as the temperature that caused50% injury (T50) from electrical conductivity. Endogenous ABAwas measured using an indirect enzyme-linked immunosorbant assay,and novel proteins were detected using 2-dimensional polyacrylamidegel electrophoresis. The maximum decrease in T50 for root tissuewas 1C for all genotypes, regardless of treatment. For Alaskashoot tips and epicotyl tissue, exogenous ABA increased thefreezing tolerance by 1.5 to 4.0C, while coldtreatment increased the freezing tolerance by 7.5 to14.8C. Cold treatment increased the freezing toleranceof shoot tips by 9 and 15C for wiland wild-type, respectively. Cold acclimationincreased endogenous ABA concentrations in Alaskashoot tips and epicotyls 3- to 4-fold. Immunogold labeling increasednoticeably in the nucleus and cytoplasm of the epicotyl after7 d at 2C and was greatest after 30 d at the time of maximumfreezing tolerance and soluble ABA concentration. Cold treatmentinduced the production of seven, three, and two proteins inshoot, epicotyl, and root tissue of Alaska, respectively.In Alaska shoot tissue, five out of seven novelproteins accumulated in response to both ABA and cold treatment.However, only a 24 kDa protein was produced in wiland wild-type shoot and epicotyl tissues aftercold treatment. Abscisic acid and cold treatment additivelyincreased the freezing tolerance of pea epicotyl and shoot tissuesthrough apparently independent mechanisms that both resultedin the production of a 24 kDa protein. Key words: Pisum sativum, cold acclimation, immuno-localization 相似文献
18.
Influence of Flooding on Net CO2Assimilation, Growth and Stem Anatomy of Annona Species 总被引:1,自引:0,他引:1
NUNEZ-ELISEA ROBERTO; SCHAFFER BRUCE; FISHER JACK B.; COLLS ANGEL M.; CRANE JONATHAN H. 《Annals of botany》1999,84(6):771-780
A series of experiments was conducted to assess net CO2assimilationand growth responses to waterlogging of grafted and seedlingtrees in the genus Annona. Seedlings of A. glabra, A. muricataandA. squamosa L., and scions of Gefner atemoya(A. squamosaxA. cherimola Mill.), 49-11 (GefneratemoyaxA. reticulata L.), 4-5 (PriestleyatemoyaxA. reticulata), A. reticulata grafted onto either A.glabra, A. reticulata orA. squamosa rootstocks were floodedfor up to 60 d. Soil anaerobiosis occurred on the third dayof flooding. Seedlings ofA. glabra and A. muricata, and thescions 49-11, Gefner atemoya, andA. reticulata grafted onto A. glabra rootstock were consideredflood tolerant based on their ability to survive and grow inflooded conditions. Scions of the normally flood-sensitive A.reticulata, Gefner atemoya, and 49-11tolerated root waterlogging when grafted onto the flood-tolerantspecies, A. glabra. In contrast, flooding of A. squamosa seedlingsand rootstocks, and A. reticulata rootstocks greatly reducedgrowth and net CO2assimilation rates, and resulted in 2080%tree mortality. Stem anatomical responses to long-term flooding(12 continuous months) were assessed in seedlings of A. glabraand A. muricata, and trees of 49-11 grafted ontoA. glabra. Flooded trees developed hypertrophied stem lenticels,particularly in A. glabra, and enlarged xylem cells resultingin thicker stems with reduced xylem density. Flooding did notincrease air spaces in pre-existing xylem near the pith or inxylem tissue that was formed during flooding. Thus, flood tolerancedid not involve aerenchyma formation in the stem. Copyright1999 Annals of Botany Company Flood tolerance, net CO2assimilation, photosynthesis, stem anatomy, shoot growth, anaerobiosis, Annonaceae. 相似文献
19.
A general modelling approach was used to predict the changesresulting from dehydration in the Young's modulus (E) of a tereteorgan with a simple anatomy (e.g. hypodermis of thick-walledtissue surrounding a parenchymatous core of ground tissue).Two general anatomical models were investigated: (1) an apoplastmodel in which each cross section through the organ wasconsidered as a composite elastic material consisting of a solid(cell wall) and liquid (protoplasm) phase; and (2) a core-rindmodel in which the organ consisted of a thick-walledand a thin-walled tissue. For each of these two anatomical models,two composite material models were considered, i.e. a Voigtor Reuss equation was used to predict the changes in E attendingdehydration. The predictions from the variants of the generalmodel were evaluated on the basis of observed changes in E ascylindrical segments of the pseudopetioles of Spathiphyllumwere allowed to desiccate at room temperature. Statistical comparisonsbetween predicted and observed values of E revealed that oneof the simple variants of the model, the Voigt apoplastmodel, was the most successful in predicting the observedtrend seen in the changes in E. However, when the Voigt andReuss apoplast models were combined, the hybridmodel provided estimates of changes in E that were statisticallyindistinguishable from those observed. Based on the hybrid model,it was estimated that roughly 76.7% of the tissues with a representativeSpathiphyllum pscudopetiole operated according to a Voigt apoplastmodel. Young's modulus, dehydration, plant tissues 相似文献
20.
Welbaum G.E.; Bian D.; Hill D.R.; Grayson R.L.; Gunatilaka M.K. 《Journal of experimental botany》1997,48(3):643-654
The freezing tolerance of many plants, such as pea (Pisum sativum),is increased by exposure to low temperature or abscisic acidtreatment, although the physiological basis of this phenomenonis poorly understood. The freezing tolerance of pea shoot tips,root tips, and epicotyl tissue was tested after cold acclimationat 2C, dehydration/rehydration, applications of 104M abscisic acid (ABA), and deacclimation at 25C. Tests wereconducted using the cultivar Alaska, an ABA-deficientmutant wil, and its wildtype. Freezinginjury was determined graphically as the temperature that caused50% injury (T50) from electrical conductivity. Endogenous ABAwas measured using an indirect enzyme-linked immunosorbant assay,and novel proteins were detected using 2-dimensional polyacrylamidegel electrophoresis. The maximum decrease in T50 for root tissuewas 1C for all genotypes, regardless of treatment. For Alaskashoot tips and epicotyl tissue, exogenous ABA increased thefreezing tolerance by 1.5 to 4.0C, while coldtreatment increased the freezing tolerance by 7.5 to14.8C. Cold treatment increased the freezing toleranceof shoot tips by 9 and 15C for wiland wild-type, respectively. Cold acclimationincreased endogenous ABA concentrations in Alaskashoot tips and epicotyls 3- to 4-fold. Immunogold labeling increasednoticeably in the nucleus and cytoplasm of the epicotyl after7 d at 2C and was greatest after 30 d at the time of maximumfreezing tolerance and soluble ABA concentration. Cold treatmentinduced the production of seven, three, and two proteins inshoot, epicotyl, and root tissue of Alaska, respectively.In Alaska shoot tissue, five out of seven novelproteins accumulated in response to both ABA and cold treatment.However, only a 24 kDa protein was produced in wiland wild-type shoot and epicotyl tissues aftercold treatment. Abscisic acid and cold treatment additivelyincreased the freezing tolerance of pea epicotyl and shoot tissuesthrough apparently independent mechanisms that both resultedin the production of a 24 kDa protein. Key words: Pisum sativum, cold acclimation, immuno-localization 相似文献