Anatomy, Growth and Survival of a Long-hypocotyl Mutant of Cucumis sativus Deficient in Phytochrome B

Plant dry matter (DM) partitioning, survival rates, stem anatomy,and stem water conductivity were investigated in wild-type (WT)and long-hypocotyl (lh) mutant seedlings of cucumber (Cucumissativus) grown as isolated individuals under natural radiation.The lh mutant is severely deficient in phytochrome B. Wild-typeseedlings accumulated more DM than lh seedlings over a 4-weekgrowth period in the glasshouse. Leaf and root DM were higherin the WT but stem DM was higher in the lh mutant. Stem DM perunit length was larger in WT than in lh mutant seedlings, evenwhen the two genotypes were compared at equal whole plant DM,which was achieved by growing the plants under different irradiance.In WT seedlings, the hypocotyl was shorter but thicker, withlarger average cell diameter than the lh mutant. In hypocotyltransverse sections the area occupied by load-bearing tissues(xylem and phloem fibres) and the number and diameter of xylemvessels were larger in WT than lh seedlings. Survival ratesof the lh mutant were normal in the glasshouse but very lowoutdoors due to hypocotyl fracture. The water conductivity ofhypocotyl sections was higher in WT than lh seedlings, but nosignificant differences in water conductivity were observedwhen the root remained attached to the hypocotyl. These resultssuggest (a) that compared to the WT, tall and slender lh plantsare more susceptible to mechanical stresses created by windimpact, and (b) that if the lh lesion affects the phyB geneonly, phytochrome B plays a role in the elicitation of anatomicaland morphological changes that specifically increase fitnessin open environments.Copyright 1994, 1999 Academic Press Cucumis sativus (cucumber), light phenotypes, phytochrome, photomorphogenesis, shade phenotypes, stem growth     

Stomatal Response of some Cultivated and Wild Tuber-bearing Potatoes in Warm Tropics as Influenced by Water Deficits

Leaf resistances of 14 cultivated potato genotypes (Solanumspp) and three tuber-bearing wild Solanum species were comparedwhen plants were grown under water stress at two tropical sitesFactors investigated were diurnal changes in leaf resistance,the effect of plant age, transient drought versus well-wateredconditions of potted and field-grown plants These measurementswere carried out in order to determine the stomatal behaviourof tuber-bearing genotypes and species Significant genotypic differences in leaf resistances were notedwithin the cultivated genotypes All genotypes had higher resistanceswhen water-stressed, but LT-7 appeared to have the lowest leafresistances Genetic differences in stomatal behaviour of tuber-bearingSolanum species were confirmed Abaxial stomatal resistancesof water-stressed plants of the species ranged between 1 74and 13 8 s cm^–1 Stomata of S chacoense were less affectedby drought (three-fold) than S tuberosum (four-fold) The greatesteffect was on S jungasense (five-fold) and on S raphanifoliumThese data show that stomata behaviour among tuber-bearing Solanumspecies is sufficiently different to warrant investigationsof drought-resistance in potato species under dry hot conditions Solanum tuberosum L., Solanum raphanifolium, Solanum chacoense, Solanum jungasense, leaf resistance     

长爪沙鼠寄生蚤指数和气象因子关系的研究

根据内蒙古自治区土默特平原1983～1985年长爪沙鼠 Meriones unguiculatus巢蚤、体蚤、洞干蚤指数和6项气象资料进行分析,得到如下结果。① 共获蚤11种, 其中秃病蚤蒙冀亚种Nosopsyllus laeviceps kuzenkovi(67.50%)是优势种, 二齿新蚤Neopsylla bidentatiformis(22.65%)为次优势种。② 3种蚤指数的均值差异显著(P<0.0001)。③ 体蚤与洞干蚤指数相关显著(P<0.05), 模型为(洞干蚤指数)=0.0049+0.0248(体蚤指数), 巢蚤与体蚤、巢蚤与洞干蚤指数的相关不显著(P>0.25)。④ 沙鼠密度与3种蚤指数的相关均不显著(P>0.10)。⑤ 在巢蚤中,月温度是影响巢秃病蚤唯一的气象因子(P<0.05)。⑥ 分别求出鼠体的秃病蚤和同形客蚤指名亚种Xenopsylla conformis conformis与气象因子的最优回归子集(P<0.003、P<0.05), 洞干的秃病蚤和二齿新蚤与气象因子的最优回归子集(P<0.0007、P<0.01), 月蒸发量是影响秃病蚤的最重要因子。⑦ 春季与冬季、夏季与冬季巢蚤指数差异显著(P<0.05); 春季与冬季、夏季与冬季体蚤指数差异显著(P<0.05); 春季与冬季、夏季与秋季、夏季与冬季洞干蚤指数差异显著(P<0.05)。     

Preliminary Characterization of Glutathione S-Transferases That Accumulate in Callus Cells of Pumpkin (Cucurbita maxima Duch.)

Glutathione S-transferases (GSTs; EC 2.5.1.18 [EC] ) in sarcocarptissue of pumpkin (Cucurbita maxima Duch.) fruit and in callusinduced from the tissue were examined. The specific activityof GST in the callus was 6.9-fold higher than that in the tissue.The specific activity in the callus remained constant duringcultivation. Column chromatography on DEAE-cellulose, hydroxylapatite,and S-hexylglutathione-agarose was used to fractionate solubleproteins that were precipitated by ammonium sulfate at 30% to70% saturation from homogenates of the sarcocarp tissue of pumpkinfruit and the callus and GST activity was monitored. Two andseven isozymes of GST were identified in the tissue and in thecallus, respectively. Furthermore, column chromatography onSephadex G-200 and SDS-polyacrylamide gel electrophoresis, indicatedthat these GST isozymes were homo- and heterodimers of subunitsof M_r 22,000 (Puga), and 23,000 (Pugb), 24,000 (Pugc) or 24,500(Pugd). Puga and Pugb were predominant in the sarcocarp tissueand in the callus, respectively. Puga, Pugb, Pugc and Pugd hadacidic pI values of 5.45, 5.00, 5.35 and 5.75, respectively.Rabbit antiserum against Pugb did not cross-react with the threeother subunits of GST during immunoblotting. (Received July 15, 1993; Accepted December 14, 1993)     

Replicon Size, Mean Rate of DNA Replication and the Duration of the Cell Cycle and its Component Phases in Eight Monocotyledonous Species of Contrasting DNA C Values

Various aspects of the cell cycle were measured in the apicalmeristem of primary and seminal roots of eight monocotyledonousangiosperms: Oryza sativa (0.6 pg), Zea mays (2.4 pg), Pennisetumamericanum (2.5 pg), Aegilops umbellulata (5.1 pg), Hordeumvulgare (5.5 pg), Triticum monococcum (6.2 pg), Secale cereale(8.6 pg) and Tulipa kaufmanniana (22.6 pg), representing a 38-foldvariation in DNA C values. Using 4-d-old roots of the firstseven species and 21-d-old Tulipa roots, replicon size and ratesof replication were determined by DNA fibre autoradiography,and the duration of the cell cycle and its component phasesby the percentage labelled mitoses method. When tested withDNA C value, no significant relationships existed for repliconsize, rate of DNA replication or duration of G 1. Significantpositive linear relationships were found between DNA C valueand cell cycle duration, duration of mitosis and G2 durationwhen all data were tested, but not when the Tulipa data wereexcluded. The only characters significantly related to DNA C value whenthe Tulipa data were included or excluded were the durationof S-phase, and the ratio of the interval required for a repliconto replicate its allotted DNA (Rs) to the duration of S-phase(Ds). The Rs: Ds ratio is a measure of synchrony of repliconactivation, and the higher the DNA C value the lower this ratiobecame. We concluded that there was a nucleotypic effect ofDNA C value on this ratio and that the interval between activationof replicons became protracted and hence S-phase lengthenedas C value increased. Cell cycle, NA C value, DNA replication, replicon, S-phase     

Biogeographic study of the planktonic communities of the Prince Edward Islands (Southern Ocean)

Microphytoplankton and zooplankton composition and distributionin the vicinity of the Prince Edward Islands and at the Sub-antarcticFront (SAF) were investigated in late austral summer (April/May)1996. Samples were collected for analysis of chlorophyll a concentration(Chi a), microphytoplankton and zooplankton abundance. Generally,the highest Chl a concentrations (up to 2.0 µg l^–1)and zooplankton densities (up to 192 ind. m^–3) were recordedat stations within the inter-island area while the lowest values(<0.4 µg l^–1) were observed at stations upstreamof the islands. High Chl a and zooplankton biomass values werealso associated with the SAF. Microphytoplankton were dominatedby chain-forming species of the genera Chaetoceros (mainly C.neglectus),Fragilariopsis spp. and the large diatom Dactyliosolen antarcticus.The zooplankton assemblages were always dominated by mesozooplanktonwhich at times contributed up to 98% of total zooplankton abundanceand up to 95% of total biomass. Among mesozooplankton, copepods,mainly Clausocalanus brevipes and Metridia lucens numericallydominated. Among the macrozooplankton euphausiids, mainly Euphausiavallentini, E.longirostis and Stylocheiron maximum, and chaetognaths(Sagitta gazellae) accounted for the bulk of abundance and biomass.Cluster and ordination analysis did not identify any distinctbiogeographic regions among either the microphytoplankton orzooplankton.     

Succession of bacterivorous protists on laboratory-made marine snow

Colonization and succession over time by bacterivorous protistson laboratory-made marine snow were analysed in five assaysduring 1994. Marine snow was made hom natural seawater usingrolling tanks. In all experiments, the macroaggregates werestable in size and consistency after the fourth day, and thecolonization and succession processes were similar. Newly formedmacre aggregates became colonized by heterotrophic nanoflagellateson the fourth day, mmt of them kinete plastids (Bodo designisand Rhynchomonns nasuta) and bicosoecids (Pseudobodo tremulansand Bicosoeca sp.). Sarcodines and ciliates appeared 1 day later.Among the former, the most abundant genus was Vannella sp.,while scuticociliates (Uronema marinum) and hypotrichs (Euplotesvannus and Aspidisca steini) were the most abundant ciliates.Most of the species observed in the study were more common tobenthic habitats than to pelagic ones. The planktonic existenceof the genera Bodo, Rhynchomonas, Bicosoeca, Euplotes and Aspidiscadepends on the presence of surfaces because they are poor swimmersor immotile, and Pseudobodo and Vannella need attachment forfeeding. The only pelagic protist observed was Uronema, probablybecause its opportunistic behaviour leads it to exploit enrichedenvironments such as marine snow. Flagellate and ciliate abundancesin laboratory-made macroaggregates were much higher than insurrounding water, which indicates that marine snow representsan enhanced habitat for protist growth.     

家蚕保存系统红色卵的遗传分析

用遗传背景清楚的家蚕Bombyx mori红卵（re）、白卵(w-2、pe)、第4褐卵（b-4）的标志基因系统和正常型黑卵系统与我国家蚕基因库保存的20个红色卵系统杂交,进行顺反测验,分析了它们的卵色支配基因及遗传规律。结果发现：①在03-310系统中存在家蚕卵色新突变pink egg,与红卵re 等位,基因符号为re^p,表型特征为：卵淡红色,成虫蛾眼也为淡红色;②6个系统为红卵（re）的纯合系统,还有５个系统除具有re／re基因型外,还具有支配白色卵或浅红色或橙红色卵的突变基因;③２个系统为第4褐卵（b4）的纯合系统; ④6个系统的红褐色卵为母性影响遗传;⑤发现家蚕卵色基因b-4和r-e的互补关系,b-4/b-4 re/re基因型表现为新的卵色——橙黄色。     

Intergeneric Hybridization between Species of Leymus, Psathyrostachys and Hordeum (Poaceae, Triticeae)

A total of 132 intergeneric crossing attempts (49 combinations)involving species of Leymus Hochst., Psathyrostachys Nevskiand Hordeum L. were performed, of which 103 were between Hordeumand Leymus. Embryo rescue was used throughout the experiment.Hybrids between Leymus and Psathyrostachys were difficult toobtain. Hybrid progeny were relatively easily obtained whencrossing Hordeum and Leymus. Plants from 20 different combinationswere obtained. Nineteen of these have not previously been reported.Meiotic analysis of three hybrid combinations of Hordeum x Leymusis reported. The high frequency of univalents in meiotic interphase(MI) indicates that allosyndetic chromosome pairing did notoccur, supporting the assumption that the genomes of Leymusare non-homologous to the H genomes of Hordeum.Copyright 1994,1999 Academic Press Taxonomy, Triticeae, Leymus, Psathyrostachys, Hordeum, intergeneric hybridization     

Ribulose-1,5-bisphosphate carboxylase from plants adapted to extreme environments

The K_m and V_max of ribulose-1,5-bisphosphate carboxylase (RuBPCase)in selenium absorbing plants (Astragalus flavus Barn., Astragalusrafaelensis Barn. and Stanleya pinnata Bril.) were similar toRuBPCase from tomato (Lycopersicon esculentum L. var. tropic).The pH optima for RuBPCase activity was 8.0 for L. esculentumand A. flavus and 7.0 for A. rafaelensis and S. pinnata. TheActivation Energy (E) values for the enzymes were as follows:A.flavus (21.37), S.pinnata (19.85), A. rafaelensis (19.12)and L. escudentum (18.58). The energy of activation was higherfor the desert plants as compared to the tomato. The Arrheniusplot curves were linear to 50?C far the desert plants as comparedto 45?C for tomato. Enzyme kinetics of RuBPCase from halophytic plants (Salicorniapacifica Stand., var. utahensis (Tidestrom) Munz. and Salicorniarubra Nels.) indicated the enzyme was at least as sensitiveto NaCl concentrations as the enzyme from tomato. (Received November 9, 1976; )     

Nuclear DNA Content in Twelve Species of Alstroemeria L. and Some of their Hybrids

Nuclear DNA content (2C-value), estimated through flow cytometryusing propidium iodide (PI), was shown to vary from 36.5 pgto 78.9 pg among 29 accessions of 12Alstroemeria species (2n=2x =16). The extremes were found inA. magnifica ssp.magnificaand inA. ligtu ssp.simsii , both belonging to the Chilean speciesgroup. The four Brazilian species exhibited less variation innuclear DNA content (49.8–56.4 pg), than the eight Chileanspecies (36.5–78.9 pg). Nuclear DNA content was positivelycorrelated (r =0.92,n =7,P <0.01) with the total chromosomelength. It was also positively correlated (r =0.85,n =5,P <0.01)with the length of C-bands, when only the Chilean species wereconsidered. When both karyotype parameters, length of non-C-bandedchromosome regions (x) and length of C-bands (y) were determined,it was possible to predict the nuclear DNA content (z) withthe formula z=0.65x +1.31y-0.45 (R ²=0.97,P =0.004). The DAPI fluorescence of most accessions was proportional tothe PI fluorescence (r =0.98,P <0.001), except for one accessionofA. ligtu , that had a relatively high PI/DAPI ratio (1.88).The PI/DAPI ratios of the Brazilian species were lower (1.59–1.67)than those of the Chilean species (1.68–1.88), which mightreflect a difference in base pair composition. Four groups ofspecies could be distinguished on the basis of fluorescencevalues. Diploid interspecific hybrids were shown to have a DNAcontent intermediate to the values of the parents involved.Both the PI and the DAPI fluorescence values of these hybridsapproximated the mid parent values. Tetraploids, derived fromselfing of diploids, had PI and DAPI fluorescence values thatwere twice that of the diploid hybrids. It was possible to distinguishaneuploids from euploids based on fluorescence values. Alstroemeria ; aneuploidy; C-banding; DAPI; evolution; flow cytometry; genome size; geophytes; karyotypes; Inca Lily; nuclear DNA; propidium iodide     

Aggregation of avian predators and zooplankton prey in Otago shelf waters, New Zealand

In Otago shelf waters surface swarms of krill (Nyctiphanes australis),hyperiid amphipods (Parathemisto spp.) and galatheid crab larvae(Munida gregaria) provide an abundant summer food source forplanktivores. We tested the hypothesis that aggregation of avianplanktivores depends upon the spatial distribution of theirprey. Gulls (Larus scopulinus, L.bulleri, L.dominicanus), sootyshearwaters (Puffinus griseus) and white-fronted terns (Sternastriata) showed significantly aggregated distributions. Thedistribution of birds sitting on the sea surface was correlatedwith the abundance pattern of krill but was not correlated withthe distribution of smaller hyperiid amphipods. The distributionof flying red-billed gulls (L.scopulinus), black-billed gulls(L.bulleri) and sooty shearwaters was correlated with the krilldistribution but black-backed gulls (L.dominicanus) were not.Stomach contents of black-billed gulls were dominated by krill,in contrast to sooty shearwaters, which ate a higher proportionof Minida, and black-backed gulls, which contained Munida andfish. No amphipods were found in bird stomachs. There was nosignificant correlation between bird distributions and the hydrographicregime, water depth or distance offshore. The distribution ofprey rather than hydrographic regime was a more important determinantof bird distributions at this spatial scale (2.6–12 km)and location.     

Wide-Range Distribution of Insertion Sequences Identified in B. halodurans among Bacilli and a New Transposon Disseminated in Alkaliphilic and Thermophilic Bacilli

All of the insertion sequences (ISs) except for IS663 and agroup II intron identified in the alkaliphilic Bacillus haloduransC-125 genome were also detected in nine other strains of thesame species by PCR and Southern blot analysis. The transposaseof IS653 identified in the genomes of the 10 strains of B. haloduranswas found to have become the most diversified of all ISs identifiedin the genomes of 10 strains. A new IS element designated IS661belonging to the IS1380 family with inverted repeats (IRs) 17bp in length was present within IS658 identified in the genomeof B. halodurans A59. In addition, a new transposon designatedTn3271bh was identified within the IS642 element in the A59genome, which is similar to a transposon identified in thermophilicGeobacillus stearothermophilus T-6. The new transposon, Tn3271bh,generated an 8-bp duplication of the target site sequence andcarries a 21-bp IR. On the other hand, all kinds of ISs exceptfor IS643 and IS658 were distributed in the genome of obligatelyalkaliphilic Bacillus alcalophilus. Three ISs (IS652, IS653,and IS660) and a group II intron (Bh.Int) were widely dispersedin other Bacillus species without a correlation with the phylogeneticplacement based on 16S rDNA sequences.     

Changes in Levels of Cytokinins in Etiolated Squash Seedlings after Illumination

When etiolated seedlings of squash (Cucurbita maxima Duch. cv.Houkou-aokawaamaguri) were exposed to light, their cotyledonsbegan to accumulate chlorophyll at a low rate for the firsthour but at a high rate therafter. After 0, 1 and 2 h of illumination,cytokinin levels in cotyledons, hypocotyls and roots were analyzedby ELISA (enzyme-linked immunosorbent assay) and GC-SIM (gaschromatography-selected ion monitoring). Cytokinin levels measuredby ELISA were about 10 times higher than those measured by GC-SIM,suggesting that ELISA was not suitable for the measurementsof cytokinin levels in the extracts from these tissues. Cytokininsfound by GC-SIM were t-RZ (t-ribosyl zeatin), c-RZ, t-Z (t-zeatin),c-Z, RiP (ribosyl isopentenyladenine) and iP (isopoentenyladenine).Levels of biologically active cytokinins (t-RZ and t-Z) didnot show marked changes after illumination. Levels of c-RZ andc-Z did, however, decrease in cotyledons and increase in hypocotylsafter illumination. Promotion of the accumulation of the chlorophyllin detached squash cotyledons by exogenously applied t-Z waspartially inhibited by the addition of c-Z, suggesting thatthe decrease in the endogenous level of c-Z in cotyledons ofintact seedlings after illumination permits the light-inducedformation of chlorophyll. (Received August 8, 1990; Accepted April 4, 1991)     

Study of Biomphalaria Tenagophila Tenagophila, B. t. Guaibensis and B. Occidentalis by Polymerase Chain Reaction Amplification and Restriction Enzyme Digestion of the Ribosomal RNA Intergenic Spacer Regions

Biomphalaria tenagophila tenagophila, B. tenagophila guaibensisand B. occidentalis are indistinguishable on the basis of shellmorphology and the majority of organs of the genital system.Only B. t. tenagophila is susceptible to infection with Schistosomamansoni. The identification of this species is important forepidemiological studies of schistosomiasis. Snails from differentsites in Brazil, Argentine and Uruguay were studied using thePolymerase Chain Reaction (PCR) and Restriction Fragment LengthPolymorphism (RFLP) of the Ribosomal RNA Internal TranscribedSpacers (ITS) using seven enzymes. Profiles resulting from digestionwith AluI showed some invariant species-specific products allowingcorrect identification of B. t. tenagophila, B. occidentalisand B. t. guaibensis. Profiles obtained with other enzymes didnot permit species identification as extensive intraspecificpolymorphism or invariant RFLP profiles were observed. Restriction profiles obtainedwith all enzymes were used to calculate the percentage of bandsharing between all individual snails and these data were usedfor a cluster analysis. A closer relationship between B. occidentalisand B. t. guaibensis than B. t. tenagophila and the subspeciesB. t. guaibensis was observed. Based on previous morphologicaldata and these molecular data, we propose grouping B. t. tenagophila,B. occidentalis and B. t. guaibensis into a B. tenagophila complex. (Received 22 December 1997; accepted 26 May 1998)     

Annual cycle of tintinnids in Admiralty Bay with an emphasis on seasonal variability in Cymatocylis affinis/convallaria lorica morphology

In water samples collected from the middle of Admiralty Bay(King George Island 62°08'S 58°25'W) between February1990 and January 1991, 17 Tintinnina species were noted. TotalTintinnina numbers in summer were very high (up to 5000 cellsm^–3), but species diversity was low, consisting mainlyof Cymatocylis affnislconvallaria, forma convallaria. Duringaustral winter, cell numbers were very low, but species compositionwas diverse. Cymatocylis affnislconvallaria, forma affinis,and C.affmis/convallaria, forma convallaria, the polymorphicforms of one species C.affinis/convallaria, appear to be interchangeableduring the year. The transition from one form to the other occursin the spring and autumn. The typical Tintinnina polymorphismcan be attributed to the prevailing environmental conditions.     

Leaf Properties Related to the Photosynthetic Response to Drought in Upland and Lowland Rice Varieties

Four upland and two lowland varieties were grown on floodedand dry soil in pots in a glasshouse. Photosynthetic rate (P),transpiration rate (T), and water content (W) of the secondexpanded leaf from the top of the main stem were measured undercontrolled aeration and illumination in a leaf chamber in thelaboratory, together with leaf area (La), dry matter content(DM), nitrogen content (N), stomatal frequency (Sf), and totalvessel cross-sectional area at the base of the leaf blade (Va).P/La was positively related to T/La and Sf/La among six varietieswhen they were grown on flooded soil. IR 8, a semidwarf indicalowland variety, showed the highest P/La with the highest Sf/Laand T/La. When grown on dry soil P/La was positively correlatedwith W/DM, the latter being negatively related to T/Va. Twoupland varieties, African Moroberekan and Brazilian IAC 1246,showed the highest P/La on dry soil, keeping a higher W/DM witha lower T/La and a lower T/Va. Daytime leaf diffusive conductance(l/r_L) and leaf water potential (_L) measured on the same orthe same stage leaf in the glasshouse were positively correlatedwith the W/DM measured in the laboratory among varieties grownon dry soil. Simultaneous observation of P, T and W in the laboratoryindicated nonstomatal reduction in P/La due to leaf water deficitin sensitive varieties, although these varieties also showeda markedly lower daytime l/r_L in the glasshouse as comparedwith resistant varieties. Oryza sativa L., rice, drought resistance, photosynthesis, transpiration, water deficit, stomatal frequency, vessel size     

Polyamines in Nodules from Various Plant-Microbe Symbiotic Associations

Polyamine compositions of root or stem nodules collected fromvarieties of nitrogen-fixing leguminous (22 species) and non-leguminous(5 species) plants were investigated. Relatively high concentrationsof homospermidine were observed in root or stem nodules of allthe leguminous plants. Based on the ratio of homospermidineto spermidine, legume nodules were generally characterized intotwo major groupes; one containing almost equal amounts of homospermidineand spermidine, and the other a high homospermidine/spermidineratio. Root nodules from pigeon pea (Cajanus cajan L. Millsp)was the only exception which exhibited very low homospermidine/spermidineratio. Amongst the legumes, nodules of adzuki bean (Vigna angularis),siratro (Macroptilium atropurpureum DC. Urb.), pea (Pisum sativumL.), and hairly vetch (Vicia hirsuta S.F. Gray) were rich indiamine putrescine. Such characters of nodule polyamine compositionwere inherent characteristics of each legume species, and notrelated to the type of infected rhizobia (Rhizobium or Bradyrhizobium).In contrast to herbaceous leguminous plants, nonleguminous woodyplants, which symbiotically associate with actinomycete Frankiaspecies, contained little polyamines in their root nodules.Root nodules of non-leguminous Parasponia andersonii infectedby bradyrhizobia were found to contain large quantities of putrescineand homospermidine. No significant differences in polyaminecomposition were observed between root and stem nodules bothin Aeschynomene indica and Sesbania rostrata. (Received June 13, 1994; Accepted August 17, 1994)