Grasping the heterogeneity of kettle hole water quality in Northeast Germany

Riparian vegetation typically provides substantial allochthonous material to aquatic ecosystems where micro-organisms can play an important role in organic matter degradation which can support consumer biomass. We examined the effects of leaf litter quality (e.g., leaf nutrients, lignin and cellulose content), leaf species mixing, and microbial community diversity on in-stream breakdown rates of litter from dominant riparian trees (Melaleuca argentea, M. leucadendra, and Nauclea orientalis) in both a perennial and intermittent river in Australia’s wet-dry tropics. Leaf mass remaining after 82 days of in-stream incubation was negatively correlated (P < 0.05) with initial leaf N and P content while initial lignin and cellulose content had no statistically significant effect. Breakdown rates of incubated leaves of both Melaleuca and Nauclea were significantly higher in mixed litter bags compared with single species litter bags. Although it was expected that leaf N content would decrease from initial levels during decomposition, we found either similar or slightly higher N content following in-stream incubation suggesting microbial colonisation increased overall N content. Stable isotopes of δ¹³C and δ¹⁵N for the major sources and consumers in both rivers provide evidence that leaf litter was an important macroinvertebrate food source in the perennial river where heavy shading may limit algal production. However, in the intermittent river where riparian cover was low, benthic algae were the major organic carbon source for consumers. Our findings suggest that riparian tree species influence rates of in-stream organic matter processing, microbial community composition, and aquatic food web dynamics in tropical wet-dry streams.     

Riparian plant species loss alters trophic dynamics in detritus-based stream ecosystems

Riparian vegetation is closely connected to stream food webs through input of leaf detritus as a primary energy supply, and therefore, any alteration of plant diversity may influence aquatic ecosystem functioning. We measured leaf litter breakdown rate and associated biological parameters in mesh bags in eight headwater streams bordered either with mixed deciduous forest or with beech forest. The variety of leaf litter types in mixed forest results in higher food quality for large-particle invertebrate detritivores (‘shredders’) than in beech forest, which is dominated by a single leaf species of low quality. Breakdown rate of low quality (oak) leaf litter in coarse mesh bags was lower in beech forest streams than in mixed forest streams, a consequence of lower shredder biomass. In contrast, high quality (alder) leaf litter broke down at similar rates in both stream categories as a result of similar shredder biomass in coarse mesh bags. Microbial breakdown rate of oak and alder leaves, determined in fine mesh bags, did not differ between the stream categories. We found however aquatic hyphomycete species richness on leaf litter to positively co-vary with riparian plant species richness. Fungal species richness may enhance leaf litter breakdown rate through positive effects on resource quality for shredders. A feeding experiment established a positive relationship between fungal species richness per se and leaf litter consumption rate by an amphipod shredder (Gammarus fossarum). Our results show therefore that plant species richness may indirectly govern ecosystem functioning through complex trophic interactions. Integrating microbial diversity and trophic dynamics would considerably improve the prediction of the consequences of species loss.     

Food utilization of aphidophagous hoverfly larvae (Diptera: Syrphidae, Chamaemyiidae) on herbaceous plants in an urban habitat

We examined food utilization in a community of aphidophagous hoverfly larvae (Diptera: Syrphidae and Chamaemyiidae) in open lands in an urban habitat in central Japan for 3 years. The community consisted of 17 hoverfly species feeding on 20 aphid species occurring on 14 species of dominant herbaceous plants. In terms of larval prey preference, the dominant eight species of hoverfly were categorized into three groups: a polyphagous ‘generalist’ group consisting of four species,Episyrphus balteatus, Betasyrphus serarius, Syrphus vitripennis andSphaerophoria sp.; an oligophagous ‘specialist’ group consisting of three species,Metasyrphus hakiensis, Dideoides latus andParagus hemorrhous; andLeucopis puncticornis, which showed a preference for two aphid species on the plantTorilis scabra. The prey aphids of the second group have behavioral or morphological defense mechanisms that are effective for preventing attacks by generalist hoverflies; two prey aphids are aggressive toward generalist predators and the others are protected by ant-attendance. The specialist hoverflies seem to be adapted to overcome these defense mechanisms. The prey ranges overlapped little between the generalist and the specialist groups, while those within the generalist group overlapped greatly.     

Changes in Pelagic Bacteria Communities Due to Leaf Litter Addition

In many limnetic systems, the input of allochthonous organic matter, e.g., leaf litter, is a substantial source of dissolved organic carbon (DOC) for pelagic bacteria, especially in fall and winter when autochthonous DOC production is low. However, relatively little is known about community changes of pelagic lake bacteria due to leaf litter input which includes both the release of leaf leachates and microorganisms from the leaf litter into the surrounding water. Therefore, we have experimentally studied the effects of different types of leaf litter (Betula pendula, Fagus silvatica, and Pinus silvestris) on the pelagic bacterial community composition by adding leaves to different treatments of epilimnic water samples (unfiltered, 0.2 μm and 5.0 μm-pre-filtered) from humic Lake Grosse Fuchskuhle (Northeastern Germany). The addition of leaf litter led to a significant increase in DOC concentration in lake water, and each leaf litter type produced significantly different amounts of DOC (p = <0.001) as well as of specific DOC fractions (p = <0.001), except of polysaccharides. DGGE banding patterns varied over time, between types of leaf litter, and among treatments. Bacteria belonging to known bacterial phylotypes in the southwest basin of Lake Grosse Fuchskuhle were frequently found and even persisted after leaf litter additions. Upon leaf litter addition, α-proteobacteria (Azospirillum, Novosphingobium, and Sphingopyxis) as well as β-proteobacteria (Curvibacter and Polynucleobacter) were enriched. Our results indicate that supply of leaf litter DOM shifted the bacterial community in the surrounding water towards specific phylotypes including species capable of assimilating the more recalcitrant DOC pools. Statistical analyses, however, show that DGGE banding patterns are not only affected by DOC pools but also by treatment. This indicates that biological factors such as source community and grazing may be also important for shifts in bacterial community structure following leaf litter input into different lakes.     

Effects of water quality on habitat use by lesser scaup (Aythya affinis) broods in the boreal Northwest Territories, Canada

The dynamics of Rhizophora mangle litter production and decomposition were studied in a tropical coastal lagoon on the Gulf of Mexico in Veracruz, Mexico over a year (October 2002–October 2003). This region is characterized by three seasons: northerly winds (called ‘nortes’), dry, and rainy. Annual litter production (1116 g m⁻²) followed a seasonal pattern with leaf litter as the main fraction (70%) with two peaks in the dry and one in the rainy season. Leaf decomposition was evaluated with two types of litter bag in each season: fine mesh (1×1 mm) and coarse mesh (3×7 mm). Decomposition data were adjusted to a single negative exponential model. The results indicated faster decomposition rates in the coarse litter bag and significant differences among seasons. However these differences occurred after the 60th day of decomposition, indicating that leaching and microbial action were responsible for more than 50% of mass loss. After this period, the effects of aquatic invertebrates were evident but depended on climatic conditions. In the rainy season, the gastropod Neritina reclivata was associated with increasing leaf decomposition rate. In the ‘nortes’ season, the effect of aquatic invertebrates was smaller, and there were no differences in the decay constants calculated for the two litter bag types. High litter production represents an important input of organic matter which, through decomposition, may represent an important source of C, N, and P in this aquatic system.     

Shifts in plant nutrient use strategies under secondary forest succession

In evergreen broad-leaved forests (EBLFs) in Tiantong National Forest Park, Eastern China, we studied the soil chemistry and plant leaf nutrient concentration along a chronosequence of secondary forest succession. Soil total N, P and leaf N, P concentration of the most abundant plant species increased with forest succession. We further examined leaf lifespan, leaf nutrient characteristics and root–shoot attributes of Pinus massoniana Lamb, the early-successional species, Schima superba Gardn. et Champ, the mid-successional species, and Castanopsis fargesii Franch, the late-successional species. These species showed both intraspecific and interspecific variability along succession. Leaf N concentration of the three dominant species increased while N resorption tended to decrease with succession; leaf P and P resorption didn’t show a consistent trend along forest succession. Compared with the other two species, C. fargesii had the shortest leaf lifespan, largest decay rate and the highest taproot diameter to shoot base diameter ratio while P. massoniana had the highest root–shoot biomass ratio and taproot length to shoot height ratio. Overall, P. massoniana used ‘conservative consumption’ nutrient use strategy in the infertile soil conditions while C. fargesii took up nutrients in the way of ‘resource spending’ when nutrient supply increased. The attributes of S. superba were intermediate between the other two species, which may contribute to its coexistence with other species in a wide range of soil conditions.     

Microbial community shifts influence patterns in tropical forest nitrogen fixation

The role of biodiversity in ecosystem function receives substantial attention, yet despite the diversity and functional relevance of microorganisms, relationships between microbial community structure and ecosystem processes remain largely unknown. We used tropical rain forest fertilization plots to directly compare the relative abundance, composition and diversity of free-living nitrogen (N)-fixer communities to in situ leaf litter N fixation rates. N fixation rates varied greatly within the landscape, and ‘hotspots’ of high N fixation activity were observed in both control and phosphorus (P)-fertilized plots. Compared with zones of average activity, the N fixation ‘hotspots’ in unfertilized plots were characterized by marked differences in N-fixer community composition and had substantially higher overall diversity. P additions increased the efficiency of N-fixer communities, resulting in elevated rates of fixation per nifH gene. Furthermore, P fertilization increased N fixation rates and N-fixer abundance, eliminated a highly novel group of N-fixers, and increased N-fixer diversity. Yet the relationships between diversity and function were not simple, and coupling rate measurements to indicators of community structure revealed a biological dynamism not apparent from process measurements alone. Taken together, these data suggest that the rain forest litter layer maintains high N fixation rates and unique N-fixing organisms and that, as observed in plant community ecology, structural shifts in N-fixing communities may partially explain significant differences in system-scale N fixation rates.     

Development of an optimal sampling protocol for millipedes (Diplopoda)

This study determined a millipede sampling protocol that was efficient, replicable, and thorough, by testing commonly used methods (pitfall trapping, hand collection, and leaf litter collection with Berlese extraction) at sites where the fauna had been intensively sampled, so that the results of different sampling protocols (‘experimental sampling’) could be compared to the previously known fauna of each site (determined by ‘baseline sampling’). Two methods of collecting leaf litter were compared. One method allowed the collector to choose the locations from which to sample leaf litter, while the second method used randomly generated locations. Experimental sampling took place at both an upland site (Swallow Cliff Woods, Cook Co, IL) and a wetland site (Cedarburg Bog, Ozaukee Co, WI) where reliable baseline data was available. The optimal protocol for millipedes was found to consist of a combination of the hand collection and the a priori litter methods. In studies where there are constraints on time or resources devoted to sampling or processing, this protocol can be reduced to the single most effective method, hand collection. Overall, the a priori litter collection method was more effective than the random litter collection method.     

Upper Triassic reefs of the Oman Mountains: Data from the South Tethyan margin

Summary The Upper Triassic reefal limestones of the Oman Mountains were investigated with respect to their microfacies, palaeontology and community structure. The reef fauna described and figured for the first time occurs in parautochthonous slope deposits of the Arabian platform (Sumeini Group) and in allochthonous reefal blocks (‘Oman Exotics’, Hawasina Complex). The ‘Oman Exotics’ are tectonically dislocated blocks, derived from isolated carbonate platforms on seamounts in the Hawasina basin or in the South Tethys Sea. The lithofacies and fauna of these blocks comprise a cyclic platform facies with megalodonts, reef and reef debris facies. The reefal limestones are dated as Norian/Rhaetian by benthic foraminiferal associations (Costifera, Siculocosta, Galeanella) and typical encrusting organisms (Alpinophragmium, Microtubus). Some small ‘Oman Exotics’ are of Carnian age. The shallow-marine organisms include scleractinian corals of different growth forms, ‘sphinctozoans’, ‘inozoans’ chaetetids, spongiomorphids, disjectoporids and solenoporacean algae as the main reef builders, various encrusters like microbes, foraminifers, sponges and many different problematical organisms for the stabilisation of the reef framework and a group of dwellers including benthic foraminifers, gastropods, bivalves and a few dasycladacean algae. The reef communities are characterized by the coverage of organisms and distributional pattern. Analogies with the coeval reef deposits from the European part of the Tethys have been recognized. Some species, now collected in Oman, were also reported from American and Asian localities.     

In vitro screening for burrowing nematode, Radopholus citrophilus, tolerance and resistance in commercial Anthurium hybrids

Summary A reliable method to screen Anthurium for burrowing nematode resistance and tolerance in vitro was developed using 17 genetically distinct Anthurium cultivars. Based on nonparametric data analysis, tolerance and resistance were found to be independent traits to be evaluated separately. An effective parameter for tolerance evaluation was ranking of relative leaf retention, whereas an effective parameter for resistance evaluation was the ranking of nematode reproduction, log(Rf+1). A comparison of the ranking of leaf retention with ranking of nematode reproduction clustered the cultivar responses to burrowing nematode infection into four groups: intolerant and resistant, moderately tolerant but susceptible, intolerant and susceptible, and tolerant and susceptible. ‘Ozaki’ was identified as an intolerant reference, ‘Nitta’ as a susceptible reference. ‘Blushing Bride’ was the most tolerant cultivar among those screened, but it may not be an ideal tolerant reference due to its low vigor. Future screening for burrowing nematode-tolerant and-resistant cultivars in Anthurium should include ‘Ozaki’ and ‘Nitta’ as internal controls. Evaluation of resistance should be based on a resistance index obtained by log(Rf of hybrid tested +1) divided by log(Rf of ‘Nitta’ +1); tolerance should be based on ranking of relative leaf retention.     

b-D-glucosidase activity in pelargonium and poinsettia leaves infected by <Emphasis Type="Italic">Botrytis cinerea</Emphasis> Pers. ex Fr.

The involvement of β-D-glucosidase activity in grey mould was studied in two ornamental plant species attacked by Botrytis cinerea. β-D-glucosidase activity in the susceptible pelargonium cultivar ‘Shiva’ gradually increased with the disease development in the leaf spots and their surroundings. The endogenic level of the studied hydrolase in the resistant pelargonium ‘Cascade’ was several times higher than in the susceptible cultivar ‘Shiva’ and in principle underwent no changes after inoculation. The postinfection increase in the activity of β-D-glucosidase noted in the leaves of the susceptible poinsettia cultivar ‘Malibu Red’ was evidently weaker in the intensity, but its tendencies were similar to those of the susceptible pelargonium cultivar. In the leaves of the medium-resistant poinsettia ‘Coco White’ the constitutional level of β-D-glucosidase was 2-3-fold higher in that cultivar than in the susceptible cv. ‘Malibu Red’. In attacked leaves of ‘Coco White’, the enzyme activity continued to increase temporarily until the 3^rd h after inoculation. The process of healthy leaf senescence in both species had no significant influence on the change of the studied enzyme activity which was generally low. A high activity of β-D-glucosidase was also observed in the homogenate prepared from mycelium and in the fungal spores.     

Infraspecific variability ofJuniperus L. (Cupressaceae) based on monoterpenoid compositions

The compositions of leaf monoterpenoids from 11 species in the Juniperus section (Juniperus chinensis var. chinensis,J. virginiana, J. communis var. montana,J. rigida, J. chinensis var. globosa,J. chinensis var. sargentii,J. chinensis ‘Kaizuka Variegata’,J. squamata ‘Wilsonii’,J. x media ‘Shimpake’,J. x media ‘Plamosa Aurea’, andJ. squamata ‘Aloderi’) were comparatively analyzed by GC-MS. Of the 24 compounds identified, α-pinene, myrcene, limonene, terpinolene, and bornyl acetate were common to all, but particular combinations differed remarkably among taxa. The simplest composition (eight compounds) was found in.J, chinensis var. chinensis; the most complex (19 compounds), inJ. x media ‘Shimpake’. Cluster analysis generated four distinctive clades within the Juniperus section. The minimum spanning network revealed thatJ. squamata ‘Wilsonii’ andJ. x media ‘Shimpake’ were most similar in their chemical makeup.     

Habitat requirements for the conservation of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) on the Isle of Wight, UK

In the UK, wood cricket (Nemobius sylvestris) is a ‘Species of Conservation Concern’, being restricted to only three areas in southern England. Little information is available on the specific habitat requirements of this species. In 2006, a field investigation within three woodlands on the Isle of Wight was undertaken to identify its habitat preferences. Factors positively influencing wood cricket presence within woodlands included the presence of a well-developed leaf litter layer, relatively low ground vegetation cover and height, low canopy cover and relatively short distances between individual populations. Regression models identified the degree of isolation and variables describing vegetation structure as the main predictors for wood cricket presence within woodland fragments. The results of this study indicate the preference of wood cricket for open wooded edges. Conservation efforts for this species should focus on continuation of regular management activities aimed at providing permanent open edge habitat within woodlands, to maintain viable populations.     

Hybrid origin of some ornamentals of Allium subgenus Melanocrommyum verified with GISH and RAPD

 Random amplified polymorphic DNA (RAPD) and genomic in situ hybridization (GISH) methods have been used to verify the hybridogenic origin and to identify the parental species of some ornamental cultivars in the subgenus Melanocrommyum of the genus Allium. The cultivars had been selected from seed obtained after uncontrolled pollination in breeders’ fields. The combination of GISH analysis with RAPD markers is very suitable for testing the hybridogenic origin of plants and to ascertain the parental species of the hybrids in such cases. As suspected, A. macleanii and A. cristophii are the parental species of ‘Globemaster’. The parental species of cultivar ‘Globus’ are A. karataviense and A. stipitatum, and not A. cristophii and A. giganteum as has been assumed on morphological grounds. Cultivars ‘Lucy Ball’ and ‘Gladiator’ are of hybrid origin, though only one of the parental species, A. hollandicum, could be confirmed. The cultivars ‘Purple Sensation’, ‘Mount Everest’, ‘White Giant’, ‘Michael H. Hoog’ and ‘Mars’ are not hybrids since neither GISH nor RAPD suggest the presence of a second genome. ‘Purple Sensation’ belongs to A. hollandicum, ‘Mount Everest’, ‘White Giant’ and ‘Mars’ to A. stipitatum,‘Michael H. Hoog’ to A. rosenorum. Received: 3 July 1997 / Accepted: 9 October 1997     

Differences in abscisic acid concentration in roots and leaves of two young Olive (<Emphasis Type="Italic">Olea europaea</Emphasis> L.) cultivars in response to water deficit

Differences in abscisic acid (ABA) accumulation between two olive cultivars were studied by enzyme-linked immunosorbent assay in roots and leaves, leaf water potential (Ψ_l), stomatal conductance (g _s) as well as photosynthetic rate (A) were also determined in well-watered (WW) and water-stressed (WS) plants of two olive cultivars ‘Chemlali’ and ‘Chetoui’. ‘Chemlali’ was able to maintain higher leaf CO₂ assimilation rate and leaf stomatal conductance throughout the drought cycle when compared with ‘Chetoui’. Furthermore, leaf water potential of ‘Chemlali’ decreased in lower extent than in Chetoui in response to water deficit. Interestingly, significant differences in water-stress-induced ABA accumulation were observed between the two olive cultivars and reflect the degree of stress experienced. Chemlali, a drought tolerant cultivar, accumulated lower levels of ABA in their leaves to regulate stomatal control in response to water stress compared to the drought sensitive olive cultivar ‘Chetoui’ which accumulated ABA in large amount.     

In vitro assay of native Iranian almond species (<Emphasis Type="Italic">Prunus</Emphasis> L. spp.) for drought tolerance

Eight native Iranian almond species from three sections, ‘Euamygdalus’ (Prunus communis; Prunus eleagnifolia and Prunus orientalis); ‘Lycioides’ (Prunus lycioides and Prunus reuteri) and ‘Spartioides’ (Prunus arabica, Prunus glauca and Prunus scoparia) were in vitro screened for drought tolerance using sorbitol and polyethylene glycol (PEG) as an osmoticum. Different levels of water stress were induced using five concentrations of either sorbitol or polyethylene glycol in Woody Plant Medium (WPM). Water potential of various media ranged from −0.80 to −2.05 MPa and water stress in culture medium adversely affected plantlet growth. Wild species from ‘Spartioides’ were less affected than ‘Lycioides’ and ‘Euamygdalus’. At the same level of water potential, sorbitol had lower adverse effects than PEG; the latter being severe. Prunus × sorbitol and Prunus × PEG interactions were significant. At 0.2 M sorbitol and 0.003 M PEG, ‘Spartioides’ produced significantly more roots with higher total root length and root volume, as well as root-dry weight than those of ‘Lycioides’ and ‘Euamygdalus.’ It is concluded that in vitro screening of native Iranian almond species under specific and limited water-stress conditions may provide a system for effectively differentiating the wild species of almond for their expected root mass production under field conditions.     

Description ofAvesicladiella gen. nov. (hyphomycetes) for two undescribed leaf litter microfungi

The new hyphomycete genusAvesicladiella with two species,A. britannica sp. nov., type species, andA. microsperma sp. nov., is described and illustrated. Both species are leaf litter microfungi. The genus closely resemblesVesicladiella, Circinotrichum, Gyrothrix, Ceratocladium andVermiculariopsiella, several hyphomycete genera with comparable characters such as superficial hyphal networks; production of setae; absence of conidiophores; lageniform or ampulliform conidiogenous cells; and hyaline aseptate conidia produced in clusters around the apices of conidiogenous cells. The new genus differs from these by its hyaline, septate setae, typical ‘phialidic’ conidiogenous cells, and hyaline, aseptate cylindrical conidia.     

Isolation,Characterization, and Expression Analysis of an <Emphasis Type="Italic">SKP1-</Emphasis>like Gene from ‘Shatian’ Pummelo (<Emphasis Type="Italic">Citrus grandis</Emphasis> Osbeck)

Plant s-phase kinase-associated protein 1 (SKP1) genes have diverse functions in plant developmental and physiological activities. Herein, we described a novel SKP1 gene, designated as CgSKP1, from ‘Shatian’ pummelo (Citrus grandis Osbeck). The cDNA sequence of CgSKP1 was 603 bp and contained an open reading frame of 477 bp. Genomic sequence of the CgSKP1 gene contained two exons and one intron. The predicted amino acid sequence of this gene is consisted of 158 amino acids with theoretical proteins size of 17.9 kDa. CgSKP1 had high identity with SKP1 genes from other plant species within two conserved region. Full-length cDNAs were also amplified and cloned from six citrus varieties, with 95% nucleotide identity and about 98% amino acid similarity among them. Gel blot analysis suggested that CgSKP1 existed as a single locus in the ‘Shatian’ pummelo genome. The expression of CgSKP1 was gradually increased during flower developmental stages in ‘Shatian’ pummelo. Moreover, expression analysis by RT-PCR, qRT-PCR and in situ hybridization of CgSKP1 showed that it was highly expressed in the leaf, petal, anther and ovary, but lowly in the style. These findings indicated that CgSKP1 was closely related to ‘Shatian’ pummelo flower development.     

Is there a link between the type of habitat and the patterns of abundance of holothurians in shallow rocky reefs?

The presence of a mosaic of habitats, largely determined by sea urchin grazing, across shallow rocky reefs may potentially influence in differences in the distribution patterns of invertebrates. The aim of this paper was to assess, using a correlative approach, whether the type of habitat influences the abundance patterns of holothurians in the eastern Atlantic. We hypothesized that abundances of large (> 10 cm) holothurians varied among four types of habitat (3 vegetated habitats with low abundances of the sea urchin D. antillarum vs. ‘barrens’ with hyperabundances of sea urchins), and that these differences were consistent at a hierarchy of spatial scales, including two islands and several replicated sites within each type of habitat and island. Three species of large holothurians were found, accounting for a total of 300 specimens. We found remarkable differences in abundances of holothurians between the ‘barrens’ and the three vegetated habitats. This pattern was strongest for the numerically dominant species, Holothuria sanctorii. Total abundances of holothurians were between 5 and 46 times more abundant in ‘barrens’ compared with the vegetated habitats. Inter-habitat differences were species-specific with some inconsistent patterns from one island to the other. The total abundances of holothurians tended to increase with the abundance of sea urchins within ‘barrens’. Our study suggests that there may be a link, at least for the dominant species Holothuria sanctorii, between the distribution and abundances of large holothurians and the habitat across shallow-waters of the eastern Atlantic.     

The effect of phosphorus deficiency on nutrient uptake,nitrogen fixation and photosynthetic rate in mashbean,mungbean and soybean

Phosphorous (P) fertilization is the major mineral nutrient yield determinant among legume crops. However, legume crops vary widely in the ability to take up and use P during deficiency. The aim here was to compare P uptake and translocation, biological nitrogen fixing ability and photosynthetic rate among mashbean (Vigna aconitifolia cv. ‘Mash-88’), mungbean (Vigna radiata cv. ‘Moong-6601’) and soybean (Glycine max L. cv. ‘Tamahomare’) during deficiency in hydroponics. Two treatments, the withdrawal of P from the solution (P-deprivation) and continued P at 160 μM (P sufficient) were effected at the pod initiation stage. Plants were grown for 20 days. Short-term labeling with ³²P showed the uptake and distribution of P into plant parts. Withdrawal of P from the solution reduced biomass, photosynthetic activity, and nitrogen fixing ability in mungbean, and mashbean more than in soybean. P deprivation decreased P accumulation more than N accumulation. The decrease was more severe in mungbean and mashbean than soybean. More P was translocated and distributed into leaves in soybean than in mungbean and mashbean. Leaf P amount was more correlated to leaf area than to photosynthetic rate per unit leaf area among all three legume species. The results indicate that selection for increased efficiency of P utilization and leaf area may be used to improve leguminous crops.