Publications

isolation and characterization of symbiotic mutants of bradyrhizobium sp. (arachis) strain nc92: mutants with host-specific defects in nodulation and nitrogen fixation.	random transposon tn5 mutagenesis of bradyrhizobium sp. (arachis) strain nc92, a member of the cowpea cross-inoculation group, was carried out, and kanamycin-resistant transconjugants were tested for their symbiotic phenotype on three host plants: groundnut, siratro, and pigeonpea. two nodulation (nod- phenotype) mutants were isolated. one is unable to nodulate all three hosts and appears to contain an insertion in one of the common nodulation genes (nodabcd); the other is a host-specific nodula ...	1987	3032910
gtp-binding domain: three consensus sequence elements with distinct spacing.	a sequence comparison of nine functionally different gtp-binding protein families has yielded further information on the general characterization of the conservation and importance of amino acid sequences in the gtp-binding domain, including a consensus sequence composed of three consensus elements gxxxxgk, dxxg, and nkxd with consensus spacings of either 40-80 or approximately equal to 130-170 amino acid residues between the first and second elements and approximately 40-80 amino acid residues ...	1987	3104905
contribution of cowpea (vigna unguiculata) in a mixed diet to the nutrient intake of rural children in ibadan.	1. sixty-four subjects from the rural areas of ibadan participated in a study to determine the contribution of cowpea (vigna unguiculata) foods to the total intake of nutrients in a mixed diet. the subjects were randomly selected from those who, according to their mothers, reacted to cowpea foods (reactors) and those who did not (non-reactors). 2. the results showed that for all subjects, protein, energy and riboflavin needs were not met from the total diet consumed. however, the requirements fo ...	1987	3620436
proteolytic activity of the cowpea mosaic virus encoded 24k protein synthesized in escherichia coli.	the function of the 24-kilodalton (24k) protein encoded by cowpea mosaic virus (cpmv) has been studied by constructing a bacterial expression plasmid that contained a cloned chimeric segment consisting of partial dna copies of cpmv m-rna (including sequences coding for both capsid proteins) and b-rna (including sequences coding for the 24k protein). viral sequences were transcribed from the phage t7 promoter phi 10 of plasmid pt7-6 using t7-rna polymerase expressed from plasmid pgp1-2 present in ...	1987	3300014
sequence and organization of southern bean mosaic virus genomic rna.	the genomic rna sequence of the cowpea strain of southern bean mosaic virus (sbmv-c) has been determined. the genome is 4194 nucleotides in length and has four open reading frames. a 5' proximal open frame, from base 49 to base 603, corresponds to the length of the p4 proteins translated in cell-free extracts from full-length and smaller virion rna. the largest open frame extends from base 570 to base 3437 and encodes the two largest proteins translated in cell-free extracts from full-length vir ...	1987	2823471
phytochrome regulation of the response to exogenous gibberellins by epicotyls of vigna sinensis.	the elongation rate of cowpea epicotyls from whole cowpea (vigna sinensis) seedlings and derooted and debladed plants (explants) increased after the main light period (8-hour duration) was extended with either continuous low intensity tungsten light or brief (5 minutes) far-red (fr) irradiation. this end-of-day fr effect was reversed by red (r) irradiation suggesting the involvement of phytochrome. these results confirm and extend those obtained previously with other species. localization studie ...	1987	16665660
elicitation of necrosis in vigna unguiculata walp. by homogeneous aspergillus niger endo-polygalacturonase and by alpha-d-galacturonate oligomers.	endo-polygalacturonase (pg) was purified from a commercial preparation of aspergillus niger pectinase by means of carboxymethylcellulose chromatography, preparative isoelectric focusing, and gel permeation through sephadex g-50. the enzyme was electrophoretically homogeneous and consisted of a single polypeptide chain with a molecular weight of 33,500. the enzyme exhibited a specific activity significantly higher than those of purified polygalacturonases from phytopathogenic fungi. galacturonate ...	1987	16665750
detection of a novel protein encoded by the bottom-component rna of cowpea mosaic virus, using antibodies raised against a synthetic peptide.	a peptide was synthesized that corresponded to a sequence in the cowpea mosaic virus bottom-component rna-encoded 200-kilodalton polyprotein showing homology to the picornaviral 3c proteases. by injecting a rabbit with this peptide, antibodies were obtained that allowed the detection of a novel viral protein derived from the 200-kilodalton polyprotein. this protein, which had a size of 24 kilodaltons was found in both infected cowpea leaves and cowpea protoplasts.	1987	16789262
inhibition of cleavage of a plant viral polyprotein by an inhibitor activity present in wheat germ and cowpea embryos.	in rabbit reticulocyte lysate, the bottom component rna of cowpea mosaic virus directs the synthesis of a 200,000-molecular-weight precursor protein (200k protein) that is cleaved during synthesis by a reticulocyte enzyme to form a 32k protein and a 170k protein. cleavage of the 200k protein was found to be effectively inhibited by inhibitor activity in wheat germ and cowpea embryo extracts. the inhibitor was nondialyzable, precipitatable by ammonium sulfate, and partially stable at high tempera ...	1987	16789263
rhizobium symbiotic genes required for nodulation of legume and nonlegume hosts.	parasponia, a woody member of the elm family, is the only nonlegume genus whose members are known to form an effective nitrogen-fixing symbiosis with bradyrhizobium or rhizobium species. the bradyrhizobium strain rp501, isolated from parasponia nodules, also nodulates the legumes siratro (macroptilium atropurpureum) and cowpea (vigna unguiculata). to test whether some of the same genes are involved in the early stages of legume and nonlegume nodulation, we generated transposon tn5 insertions in ...	1987	16593814
k regulates bacteroid-associated functions of bradyrhizobium.	cowpea bradyrhizobium 32h1 cells, when grown under 0.2% o(2), synthesize nitrogenase, as well as a methylammonium (ammonium) transport system and an electrogenic k(+)/h(+) antiporter. this effect was seen in growth medium containing 8-12 mm k(+) but not with 50 mum k(+). addition of k(+) to cells growing under low o(2) tensions in low-k(+) medium led to various phenotypic properties associated with bacteroids, including the ability to reduce acetylene, induction of an ammonium transport carrier ...	1987	16593858
in vitro expression of a full-length dna copy of cowpea mosaic virus b rna: identification of the b rna encoded 24-kd protein as a viral protease.	double-stranded cdna was synthesized from b component rna of cowpea mosaic virus and cloned into appropriate vectors. using four clones, together representing the entire b rna sequence, a full-length dna copy was constructed and subsequently positioned downstream of a phage sp6 or t7 promoter. rna molecules transcribed from this full-size dna copy using sp6 or t7 rna polymerase were efficiently translated in rabbit reticulocyte lysates into a 200-kd polypeptide similar to rna isolated from viral ...	1987	16453750
nitrous oxide reduction in nodules: denitrification or n(2) fixation?	detached cowpea nodules that contained a nitrous oxide reductase-positive (nor) rhizobium strain (8a55) and a nitrous oxide reductase-negative (nor) rhizobium strain (32h1) were incubated with 1% n(2)o (95 atom% n) in the following three atmospheres: (i) aerobic with c(2)h(2) (10%), (ii) aerobic without c(2)h(2), and (iii) anaerobic (argon atmosphere) without c(2)h(2). the greatest production of n(2) occurred anaerobically with 8a55, yet very little was formed with 32h1. although acetylene reduc ...	1987	16347344
asymbiotic acetylene reduction by a fast-growing cowpea rhizobium strain with nitrogenase structural genes located on a symbiotic plasmid.	a procedure was designed which enabled the detection of ex planta nitrogenase activity in the fast-growing cowpea rhizobium strain ihp100. nitrogenase activity in agar culture under air occurred at a rate similar to that found for bradyrhizobium strain cb756 but lower than that for rhizobium strain ors571. hybridization studies showed that both nod and nif genes were located on a 410-kilobase sym plasmid in strain ihp100.	1986	16347045
inoculation response of legumes in relation to the number and effectiveness of indigenous rhizobium populations.	the response of legumes to inoculation with rhizobia can be affected by many factors. little work has been undertaken to examine how indigenous populations or rhizobia affect this response. we conducted a series of inoculation trials in four hawaiian soils with six legume species (glycine max, vigna unguiculata, phaseolus lunatus, leucaena leucocephala, arachis hypogaea, and phaseolus vulgaris) and characterized the native rhizobial populations for each species in terms of the number and effecti ...	1986	16347046
fermentation of aqueous plant seed extracts by lactic acid bacteria.	the effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (vigna unguiculata), peanut (arachis hypogea), soybean (glycine max), and sorghum (sorghum vulgare) were studied. the bacteria investigated were lactobacillus helveticus, l. delbrueckii, l. casei, l. bulgaricus, l. acidophilus, and streptococcus thermophilus. organisms were inoculated individually into all of the seed extracts; l. bulgaricus and s. thermophilus were also evaluated tog ...	1986	16347053
transport of gibberellin a(1) in cowpea membrane vesicles.	the permeability properties of gibberellin a(1) (ga(1)) were examined in membrane vesicles isolated from cowpea hypocotyls. the rate of ga(1) uptake was progressively greater as ph decreased, indicating that the neutral molecule is more permeable than anionic ga(1). membrane vesicles used in this study possessed a tonoplast-type h(+)-translocating atpase as assayed by mgatp-dependent quenching of acridine orange fluorescence and methylamine uptake. however, ga(1) uptake was not stimulated by mga ...	1986	16664723
two indirect methods for detecting ureide synthesis by nodulated legumes.	two methods were developed for the detection of altered ureide metabolism in legume nodules. both techniques are based on the positive correlation between the presence of high xanthine dehydrogenase (ec 1.2.1.37) specific activity in nodules and the ability of those nodules to produce the ureides, allantoin and allantoic acid. in the first method, nodulated legumes are treated for 2 weeks with a soil drench of allopurinol. after allopurinol treatment, leaves of n(2)-fed, ureide-producing legumes ...	1986	16664857
species variation in the predawn inhibition of ribulose-1,5-bisphosphate carboxylase/oxygenase.	the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase was measured in extracts of leaves collected before dawn (predawn activity, pa) and at midday (midday activity, ma). twenty-three of the 37 species examined showed a pa/ma ratio (</=0.75, while only capsicum frutescens, cucumis sativa, glycine max, nicotiana tabacum, vigna unguiculata, and 3 solanum species showed a pa/ma ratio </=0.5. phaseolus vulgaris consistently showed a pa/ma ratio of </=0.1. activities and pa/ma ratios of the ...	1986	16665155
cleavage of a viral polyprotein by a cellular proteolytic activity.	the 200,000-dalton polyprotein encoded by the bottom component rna of cowpea mosaic virus was synthesized in rabbit reticulocyte lysates, and this in vitro-synthesized protein was isolated from the lysate reaction mixture by sucrose density gradient centrifugation. incubation of the isolated polyprotein with buffer caused no change in the protein, but incubation with reticulocyte lysates or with fractionated lysate proteins resulted in cleavage of the protein into the expected cleavage products ...	1986	3003387
gene cluster of pseudomonas syringae pv. "phaseolicola" controls pathogenicity of bean plants and hypersensitivity of nonhost plants.	loss of the ability of pseudomonas syringae pv. "phaseolicola" nps3121 to elicit a hypersensitive response on tobacco and other nonhost plants was associated with loss of pathogenicity on the susceptible host bean. eight independent, prototrophic transposon tn5 insertion mutants which had lost the ability to elicit a hypersensitive response on tobacco plants were identified. six of these mutants no longer produced disease lesions on primary leaves of the susceptible bean cultivar red kidney and ...	1986	3023280
effects of storage and processing on the nutritive value of certain nigerian foods.	the effects of storage and processing on the nutritive value of two nigerian foods--raw cowpea (vigna unguiculata) flour and palm oil, have been investigated. increased retention of both thiamine and riboflavin as a result of increased water activity (aw) were recorded for cowpea flour stored for 6 months. a storage temperature of 5 degrees c led to minimal losses of both vitamins in the stored flour. differences in physico-chemical characteristics were observed between palm oil produced by the ...	1986	3743721
the application of protein concentrates from locally available legumes in the development of weaning foods.	the effect of mixing different sources of vegetable proteins from legumes in the preparation of infant weaning foods was investigated. melon, cowpea and soya as sole protein sources or as a mixture were fed to 60 albino rats. a milk powder-based commercial product (cerelac) was used as control diet. the mixture of the vegetable protein diet compared favorably with the control diet in terms of growth rate, protein efficiency ratio (per) and net protein ratio (npr) and also ensured optimum nitroge ...	1986	3825189
enzymes of the beta-ketoadipate pathway are inducible in rhizobium and agrobacterium spp. and constitutive in bradyrhizobium spp.	protocatechuate is a universal growth substrate for members of the family rhizobiaceae, and these bacteria utilize the aromatic compound via the beta-ketoadipate pathway. this report describes transcriptional controls exercised by different subgroups of the rhizobiaceae over five enzymes that catalyze consecutive reactions in the pathway: protocatechuate oxygenase (ec 1.13.11.3), beta-carboxy-cis,cis-muconate lactonizing enzyme (ec 5.5.1.2), gamma-carboxymuconolactone decarboxylase (ec 4.1.1.44) ...	1986	3941043
identification of rhizobium plasmid sequences involved in recognition of psophocarpus, vigna, and other legumes.	symbiotic dna sequences involved in nodulation by rhizobium must include genes responsible for recognizing homologous hosts. we sought these genes by mobilizing the symbiotic plasmid of a broad host-range rhizobium mpik3030 (= ngr234) that can nodulate glycine max, psophocarpus tetragonolobus, vigna unguiculata, etc., into two nod- rhizobium mutants as well as into agrobacterium tumefaciens. subsequently, cosmid clones of pmpik3030a were mobilized into nod+ rhizobium that cannot nodulate the cho ...	1986	3958042
rna-directed rna polymerases from healthy and from virus-infected cucumber.	much work has been done on the isolation, purification, and characterization of the rna-directed rna polymerase (ec 2.7.7.48) of cucumber mosaic virus (cmv)-infected cucumbers. uninfected plants were reported to have no such enzyme, but we recently detected low levels of the activity in cucumber. since tobacco and cowpea contain such an enzyme that is variably increased in amount by various virus (as well as viroid) infections, we assumed that this would also be the case upon cmv infection of cu ...	1986	3458203
molecular cloning and sequence determination of the genomic regions encoding protease and genome-linked protein of three picornaviruses.	to investigate the degree of similarity between picornavirus proteases, we cloned the genomic cdnas of an enterovirus, echovirus 9 (strain barty), and two rhinoviruses, serotypes 1a and 14lp, and determined the nucleotide sequence of the region which, by analogy to poliovirus, encodes the protease. the nucleotide sequence of the region encoding the genome-linked protein vpg, immediately adjacent to the protease, was also determined. comparison of nucleotide and deduced amino acid sequences with ...	1986	3512851
molecular assembly of tobacco mosaic virus in vitro.	tmv assembly starts with a specific interaction between the assembly origin on the rna and a disk aggregate of coat protein. the assembly origin is located in the 30k protein cistron for common and tomato strains of tmv and in the coat protein cistron for cowpea strain of tmv and for cgmmv. all the assembly origins have three essential structures: a long base-paired hairpin loop structure; a target sequence, gapuguug, at the top of the hairpin loop structure; and a tract where every third base i ...	1986	3551520
comparison of hup trait and intrinsic antibiotic resistance for assessing rhizobial competitiveness axenically and in soil.	the competitiveness of dual-strain inocula of cowpea rhizobia for nodulation of vigna unguiculata (l.) walp. was studied axenically between one slow-growing strain (p132, hp147, 401, or 22a1) and one fast-growing strain (176a26 or 176a28) at logarithmic inoculum ratios ranging from 10 to 10. nodule infectivity was determined by multiple intrinsic antibiotic resistance, since both fast-growing strains were sensitive. different hydrogen uptake (hup) efficiencies of dual-strain inocula allowed for ...	1986	16347016
the primary structure of red clover mottle virus middle component rna.	the primary structure of middle component rna of red clover mottle virus (rcmv) has been determined. the rna is polyadenylated, has a small protein (vpg) covalently linked to its 5' terminus and consists of 3543 nucleotides. the rna possesses a single long open reading frame which can code for a polypeptide of molecular weight 109,452. comparison of the 3' terminal sequence of the m rna with that of the homologous b rna reveals a high degree of sequence conservation in this area. computer-assist ...	1986	18640659
swelling of isometric and of bacilliform plant virus nucleocapsids is required for virus-specific protein synthesis in vitro.	encapsidated rna of cowpea chlorotic mottle virus (ccmv), brome mosaic virus (bmv), alfalfa mosaic virus, and southern bean mosaic virus can act as templates for protein synthesis when preswollen virions are added to a wheat germ extract, or when unswollen virions swell in the extract. encapsidated rna of turnip yellow mosaic virus, whose particles are unlikely to swell under the conditions used here, did not act as a template. ccmv and bmv, swollen in the extract, gave relatively more rna 1 and ...	1986	18640565
alfalfa mosaic virus temperature-sensitive mutants. iii. mutants with a putative defect in cell-to-cell transport.	forty-five mutants of alfalfa mosaic virus with a temperature-sensitive (ts) replication in tobacco leaf discs were assayed in cowpea protoplasts at 25 and 30 degrees . the extent of replication of 9 mutants at 30 degrees was less than 10% of that at 25 degrees, whereas the replication of 14 mutants was not affected at 30 degrees. twenty-two mutants showed an intermediate ts behavior. several mutants with a non-ts phenotype in cowpea protoplasts were also found to be non-ts in their replication ...	1986	18640651
determination of affinity constants and the number of binding sites of monoclonal antibodies specific for southern bean mosaic virus.	values of the equilibrium dissociation constant and the number of attachment sites for the binding of radiolabeled f(ab) fragments prepared from four monoclonal antibodies to southern bean mosaic virus have been determined. monoclonal antibodies b6 and b10 produced against the bean type strain of southern bean mosaic virus (sbmv-b) and 1c4 and 1d6 produced against the cowpea type strain (sbmv-c) were more reactive with the untreated virus than with edta-swollen particles. b6 and b10 reacted with ...	1986	18640656
xiphidorus amazonensis n. sp. (nematoda: longidoridae) from the brazilian amazon basin.	xiphidorus amazonensis n. sp. was found in the rhizospheres of jatropha curcas, musa sp., anona muricata, cassia tora, panicum laxum, paspalum fasciculatum, aeschynomene sensitiva, saccharum officinarum, manihot esculenta, abelmoschus esculentus, tamarindus indica, mangifera indica, vigna unguiculata, zea mays, commelina sp., cyperus rotundus, fimbristylis miliacea, citrus sinensis, and eichhornia crassipes on the amazon river island of xiborena, approximately 40 km southeast of manaus, capital ...	1985	19294098
alfalfa mosaic virus temperature-sensitive mutants. i. mutants defective in viral rna and protein synthesis.	the replication in cowpea protoplasts of temperature-sensitive (ts) mutants of alfalfa mosaic virus (aimv) was studied at the permissive (25 degrees) and the restrictive (30 degrees) temperature. using the northern blot hybridization technique, it was shown that at the restrictive temperature two rna 1 mutants, bts 03 and bts 04, and two rna 2 mutants, mts 03 and mts 04, were all defective in the synthesis of viral minus-strand rna, whereas the synthesis of the plus-strand genomic rnas 1, 2, and ...	1985	18639838
alfalfa mosaic virus temperature-sensitive mutants. ii. early functions encoded by rnas 1 and 2.	mutants bts 03 and mts 04 of alfalfa mosaic virus (aimv) have temperature-sensitive mutations in genomic rnas 1 and 2, respectively. these mutants are defective in the production of viral minus-strand rna, coat protein, and infectious virus when assayed in cowpea protoplasts at the nonpermissive temperature (30 degrees). to determine the temperature-sensitive step in the replication cycle, mutant-infected protoplasts were shifted from an incubation temperature of 25 degrees (permissive temperatu ...	1985	18639839
human interferon does not protect cowpea plant cell protoplasts against infection with alfalfa mosaic virus.	orchansky et al. (p. orchansky, m. rubenstein, and i. sela), proc. natl. acad. sci. usa 79, 2278-2280, 1982) reported that natural and recombinant human interferon (huifn), e.g., huifn-beta and -alpha subspecies gamma3, protects plant cells from infection with a plant virus (tobacco mosaic virus). for their study they used tobacco leaf discs as well as tobacco protoplasts. it is now reported that recombinant huifn-beta and huifn-alpha2 do not significantly decrease alfalfa mosaic virus increase ...	1985	18639858
independent replication of cowpea mosaic virus bottom component rna: in vivo instability of the viral rnas.	we compared the accumulation of cowpea mosaic virus (cpmv) rnas after inoculation of cowpea and chenopodium quinoa protoplasts with bottom (b) or middle (m) component virions alone, or with a mixture of the m and b components. rna extracted from infected protoplasts was subjected to quantitative spot hybridization after electrophoresis and blotting. compared to the complete m plus b mixture, the b inoculum induced (1) a reduced rate and extent of accumulation of b-rna of both the (+) and (-) pol ...	1985	18640533
cotranslational disassembly of a cowpea strain (cc) of tmv: evidence that viral rna-protein interactions at the assembly origin block ribosome translocation in vitro.	cotranslational disassembly of mixed rod-length populations of tobacco mosaic virus (tmv; vulgare, common or, u1 strain), reveals a reproducible, significant reduction in the level of expression of the intermediate-sized, subgenomic 12-rna when compared with conventional total viral rna preparations. i2-rna encodes a 30-kda protein, and recent evidence suggests that i2-rna is unusual in that it lacks a 5'-cap structure. in tmv vulgare, the assembly origin is located within the 30-kda protein-cod ...	1985	18640553
isolation of a fraction from cauliflower mosaic virus-infected protoplasts which is active in the synthesis of (+) and (-) strand viral dna and reverse transcription of primed rna templates.	sub-cellular fractions, isolated from cauliflower mosaic virus (camv)-infected turnip protoplasts, are capable of synthesising camv dna in vitro on an endogenous template and of reverse transcribing oligo dt-primed cowpea mosaic virus rna. the activity was not detected in mock-inoculated protoplasts. in vitro-labelled dna hybridized to single-stranded m13 clones complementary to the putative origins of (-) and (+) strand camv dna synthesis and to restriction endonuclease fragments encompassing m ...	1985	2409536
legume agglutinins that bind to rhizobium meliloti.	a protein found in seeds and roots of alfalfa (medicago sativa) was implicated in the specificity of the infection process, based on its binding to the symbiont rhizobium meliloti. we found an agglutinin with similar properties in seeds and roots of sweet clover (melilotis alba). the sweet clover differed from alfalfa in nodulation by a mutant strain of r. meliloti, but the agglutinins were indistinguishable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, rhizobium agglutination, a ...	1985	3988714
the accuracy of protein synthesis in reticulocyte and hela cell lysates.	the accuracy of translation in protein synthesis is measured as the rate of misincorporation of a particular amino acid, different from that specified by an mrna codon, into protein. the cowpea variant of tobacco mosaic virus, cctmv, contains no cysteine or methionine in its coat protein. translation in vitro of purified cctmv coat protein mrna by rabbit reticulocyte and hela cell lysates has been performed. the coat protein product was purified by immunoprecipitation with specific antisera, and ...	1985	4016118
the use of cowpeas (vigna unguiculata) in improving a popular nigerian weaning food.	a weaning food commonly used in nigeria was simulated by mixing processed sorghum (sorghum bicolor) with skim-milk powder (830: 170, w/w). replacing 310 g/kg sorghum with processed cowpeas (vigna unguiculata) resulted in an increase in protein content from 96 to 113 g/kg and an increase in biological value of the protein from 0.74 to 0.87. the two mixtures were compared with an established commercial baby food by a panel of nigerian mothers and all three foods were found to be equally acceptable ...	1985	4063322
novel application of quantitative immunoassays for screening seed globulins of cowpea varieties.	using antibodies raised in rabbits, radioimmunoassay (ria) and enzyme-linked immunosorbent assay (elisa) are standardized for cowpea (var. pusa barsati) seed globulins. the ria, when used to screen three stages of seed development, reveals that maximum globulins are detected at 28 days after flowering. when three different varieties of cowpea are assayed for their globulin content by ria and elisa, it is observed that the bold grain cowpea has the highest amount of related globulin as compared t ...	1985	4063471
use of intrinsic antibiotic resistance for characterisation and identification of rhizobia from nodules of vigna unguiculata (l) walp. and phaseolus vulgaris (l).	intrinsic resistance to low concentrations of antibiotics was used to characterise 83 isolates from nodules of cowpea (vigna unguiculata) and field bean (phaseolus vulgaris). characterisation and differentiation of isolates from cowpea was made difficult by associated fast-growing bacteria inside the nodule tissue. thus, reliable pure culture was difficult to secure without repeated isolation and even via nodulation of the appropriate homologous host. although the technique may be satisfactory f ...	1985	2412407
possible involvement of phage-like structures in antagonism of cowpea rhizobia by rhizobium trifolii.	a reduction in the viability of cowpea rhizobia was observed when rhizobium trifolii iari and cowpea rhizobium strain 3824 were inoculated together in soil. the reduction in number of cowpea rhizobia in soil was found to be associated with the reduction in number of nodules per plant and retardation in plant growth. an antimicrobial substance was isolated from r. trifolii which, on electron microscopic investigation, demonstrated the presence of several phage-like structures.	1985	16346736
conservation of nodulation genes between rhizobium meliloti and a slow-growing rhizobium strain that nodulates a nonlegume host.	parasponia, a woody member of the elm family, is the only nonlegume genus whose members are known to form an effective nitrogen-fixing symbiosis with a rhizobium species. the bacterial strain rp501 is a slow-growing strain of rhizobium isolated from parasponia nodules. strain rp501 also nodulates the legumes siratro (macroptilium atropurpureum) and cowpea (vigna unguiculata). using a cosmid clone bank of rp501 dna, we isolated a 13.4-kilobase (kb) ecori fragment that complemented insertion and p ...	1985	16593600
isolation and characterization of nodulation genes from bradyrhizobium sp. (vigna) strain irc 78.	an 11.76-kilobase-pair (kb) segment of dna from bradyrhizobium sp. (vigna) strain irc 78 that hybridizes to nodulation genes of rhizobium meliloti strain 41 was isolated. hybridization of the 11.76-kb dna fragment to dna from other bradyrhizobium species revealed a high degree of sequence conservation in this region. transfer of the 11.76-kb segment to nodulation-defective (nod(-)) mutants of r. meliloti restored their ability to induce nodules on medicago sativa (alfalfa). mutants of strain irc ...	1985	16593624
ecology and genetics of tropical rhizobia species.	biological nitrogen fixation (bnf) technology with special reference to rhizobium-legume symbiosis is growing very rapidly with the hope of combatting world hunger by producing cheaper protein for animal and human consumption in the third world. one can see rapid progress made in the biochemistry and molecular biology of symbiotic nitrogen fixation in general; however, less progress has been made on the ecological aspects despite the fact that an enormous amount of literature is available on ino ...	1985	14544047
plasmid-linked nif and "nod" genes in fast-growing rhizobia that nodulate glycine max, psophocarpus tetragonolobus, and vigna unguiculata.	forty-nine fast-growing rhizobium strains from the nodules of 26 different tropical legume genera were screened to find isolates that would (i) nodulate, e.g., winged beans, so producing large nodules for rna and protein isolation; (ii) also nodulate various small-seeded legumes, thus allowing screening of large numbers of mutants; and (iii) harbor plasmids containing nif structural genes as well as other functions involved in nodulation. on the basis of six different criteria, this rhizobial gr ...	1984	16593465
expression of beta-galactosidase controlled by a nitrogenase promoter in stem nodules of aeschynomene scabra.	a 365-base-pair (bp) dna fragment, containing the promoter region of the nitrogenase reductase (nifh) gene from stem rhizobium btai1, has been isolated and sequenced. the transcription initiation sites were localized at positions 152 (major initiation) and 114 (minor initiation) nucleotides upstream of the translation initiation codon. the 200-bp nucleotide sequence upstream of the nifh structural gene shows substantial homology to the corresponding nifh regions of cowpea rhizobium (100%), paras ...	1984	16593514
structural genes of dinitrogenase and dinitrogenase reductase are transcribed from two separate promoters in the broad host range cowpea rhizobium strain irc78.	the nucleotide sequence of the structural gene (nifd) coding for the alpha-subunit of dinitrogenase along with its flanking sequences has been determined in cowpea rhizobium irc78. the coding sequence consists of 1500 nucleotides, which corresponds to a predicted amino acid sequence of 500 residues and a molecular weight of 56,025. nucleotide homology to nifd from the blue-green alga, anabaena, and parasponia rhizobium, are 63% and 90%, respectively. cowpea rhizobium irc78 nifd and nifk (encodes ...	1984	16578778
mineral soils as carriers for rhizobium inoculants.	mineral soil-based inoculants of rhizobium meliloti and rhizobium phaseoli survived better at 4 degrees c than at higher temperatures, but ca. 15% of the cells were viable at 37 degrees c after 27 days. soil-based inoculants of r. meliloti, r. phaseoli, rhizobium japonicum, and a cowpea rhizobium sp. applied to seeds of their host legumes also survived better at low temperatures, but the percent survival of such inoculants was higher than peat-based inoculants at 35 degrees c. survival of r. pha ...	1984	16346460
invalidity of the concept of slow growth and alkali production in cowpea rhizobia.	a total of 103 rhizobial strains representing the cowpea miscellany and rhizobium japonicum were studied with regard to growth rate, glucose metabolic pathways, and ph change in culture medium. doubling times ranged from 1.4 +/- 0.04 to 44.1 +/- 5.2 h; although two populations of "fast-growing" and "slow-growing" rhizobia were noted, they overlapped and were not distinctly separated. twenty-four strains which had doubling times of less than 8 h all showed nadp-linked 6-phosphogluconate dehydroge ...	1984	16346589
homologous sequences in non-structural proteins from cowpea mosaic virus and picornaviruses.	computer analyses have revealed sequence homology between two non-structural proteins encoded by cowpea mosaic virus (cpmv), and corresponding proteins encoded by two picornaviruses, poliovirus and foot-and-mouth disease virus. a region of 535 amino acids in the 87-k polypeptide from cpmv was found to be homologous to the rna-dependent rna polymerases from both picornaviruses, the best matches being found where the picornaviral proteins most resemble each other. additionally, the 58-k polypeptid ...	1984	16453518
cowpea mosaic virus vpg: sequencing of radiochemically modified protein allows mapping of the gene on b rna.	a partial amino acid sequence of cowpea mosaic virus (cpmv) vpg radiochemically modified by chloramine-t and bolton-hunter reagent has been determined. vpg covalently bound to viral rna chains (vpg-rna) was iodinated with chloramine-t and bolton-hunter reagent to label tyrosine and lysine residues, respectively. [i]vpg-rna was digested with nuclease p1 and the resulting [i]vpg-pu was purified by sds-polyacrylamide gel electrophoresis and subjected to automated edman degradation. control experime ...	1984	16453534
adsorption of slow- and fast-growing rhizobia to soybean and cowpea roots.	roots of soybean (glycine max [l.] merr. cv hardee) and cowpea (vigna unguiculata [l.] walp. cv pink eye purple hull) were immersed in suspensions containing 10(4)rhizobium cells per milliliter of a nitrogen-free solution. after 30 to 120 minutes the roots were rinsed, and the distal 2-centimeter segments excised and homogenized. portions of the homogenates then were plated on a yeast-extract mannitol medium for bacterial cell counts. the adsorption capacities of four slow-growing rhizobia and a ...	1984	16663761
effects of short-term n(2) deficiency on n metabolism in legume nodules.	the study aimed to test the hypothesis that ammonia production by rhizobium bacteroids provides not only a source of nitrogen for growth but has a central regulatory role in maintaining the metabolic activity and functional integrity of the legume nodule. production of ammonia in intact, attached nodules was interrupted by short-term (up to 3 days) exposure of the nodulated root systems of cowpea (vigna unguiculata l. walp cv vita 3: rhizobium cb 756) and lupin (lupinus albus l. cv ultra: rhizob ...	1984	16663910
primary structural comparison of rna-dependent polymerases from plant, animal and bacterial viruses.	possible alignments for portions of the genomic codons in eight different plant and animal viruses are presented: tobacco mosaic, brome mosaic, alfalfa mosaic, sindbis, foot-and-mouth disease, polio, encephalomyocarditis, and cowpea mosaic viruses. since in one of the viruses (polio) the aligned sequence has been identified as an rna-dependent polymerase, this would imply the identification of the polymerases in the other viruses. a conserved fourteen-residue segment consisting of an asp-asp seq ...	1984	6207485
h+/atp stoichiometry of cowpea rhizobium sp. strain 32h1 cells grown under nitrogen-fixing and nitrogen-nonfixing conditions.	the obligate aerobe cowpea rhizobium sp. strain 32h1 in axenic culture is able to fix n2 when grown under 0.2% o2 but not when grown under 21% o2. it was, therefore, of interest to investigate atp synthesis in these cells grown under the two conditions. when respiring in buffers having phs ranging from 6 to 8.5, cells grown under either o2 tension maintained an intracellular ph more alkaline than the exterior. the transmembrane chemical gradient of h+ (delta ph) was essentially the same under bo ...	1984	6237099
rna and capsid accumulation in cowpea protoplasts that are resistant to cowpea mosaic virus strain sb.	leaf protoplasts from the arlington line of cowpea (vigna unguiculata) support only a limited increase of cowpea mosaic virus strain sb (cpmv-sb), whereas cowpea severe mosaic virus, another member of the comovirus group, replicates efficiently in arlington cowpea protoplasts. cpmv-sb replicates efficiently in protoplasts of cowpea line blackeye 5. some characteristics of the virus-specific resistance of arlington protoplasts to cpmv-sb are reported. differences between progeny cpmv-sb from arli ...	1984	6485253
replication of peanut stunt virus and its associated rna 5 in cowpea protoplasts.	peanut stunt virus (psv) rna containing psv-associated rna 5 (parna 5) was used as the inoculum in the successful infection of cowpea protoplasts. total nucleic acid extracts of protoplast samples at different times after inoculation were analyzed for the presence of psv genomic rnas and parna 5 using glyoxal denaturation, agarose gel electrophoresis, blotting to nitrocellulose, and hybridization to specific probes. it appears that (+)-stranded psv genomic rnas are synthesized up to 36 hr after ...	1984	6516215
detection of double-stranded rna by serologically specific electron microscopy.	details of a procedure for detecting double-stranded rna (dsrna) in virus and viroid infected tissue extracts using serologically specific electron microscopy are given. a method for staining dsrna, based on in situ formation of uranyl phosphate, that consistently permits the examination of dsrna by electron microscopy without shadowing with heavy metals, is described. the method provides for routine assays for dsrna in crude extracts without the variable results associated with shadowing proced ...	1984	6530480
[nutritive value of diets based on tubers and legumes consumed in 3 different proportions].	this study was an attempt to determine the nutritional value of diets based on mixtures of manioc and cowpea flours. the proportions analyzed were 87/13, 70/30 and 50/50, respectively. the effect of supplementing these diets with methionine was also investigated. the nutritional value of the diets was evaluated using as a basis the percentage of utilizable protein. findings revealed that the protein was best utilized when the percentages of manioc and cowpea flours were 50/50, with significant d ...	1984	6536219
mode of infection, nodulation specificity, and indigenous plasmids of 11 fast-growing rhizobium japonicum strains.	eleven fast-growing strains of rhizobium japonicum were characterized with respect to indigenous plasmids and abilities to infect (inf+) and nodulate (nod+) cowpea, siratro, wild soybean, and three commercial cultivars of soybean. all strains caused infection via infection threads in root hairs and consistently nodulated cowpea, siratro, and wild soybean in growth pouches. interactions with commercial cultivars of soybean were strikingly strain specific. some combinations were nod-, and infectio ...	1984	6542099
study of the genetic organisation of a plant viral rna genome by in vitro expression of a full-length dna copy.	the genetic approach for elucidating functions encoded by rna plant viruses has been hampered by the lack of methods to select desired mutants following random mutagenesis. an alternative might be to copy rna genomes into dna and use methods for site-directed mutagenesis to modify specific regions of the dna copy. transcription of the dna copy will subsequently produce viral rna with desired mutations. we have constructed a full-length dna copy of the smaller of the two cowpea mosaic virus (cpmv ...	1984	6549293
the nifh and nifdk promoter regions from rhizobium japonicum share structural homologies with each other and with nitrogen-regulated promoters from other organisms.	in several species of rhizobium the three genes which encode the nitrogenase complex are separated into two operons, nifh and nifdk. we have mapped the transcriptional promoter sites for these two operons from r. japonicum usda strain 110 by s1 protection analyses using bacterial rna isolated from soybean nodules. transcription of the nifdk operon is initiated at a site located 46 nucleotides upstream of the proposed translation initiation codon. nifh transcription initiates predominantly at a s ...	1984	6588133
proteolytic processing of the proteins translated from the bottom component rna of cowpea mosaic virus. the primary and secondary cleavage reactions.	the products of translation of cowpea mosaic virus b-rna in rabbit reticulocyte lysates are proteolytically cleaved to form a specific set of proteins. the primary cleavage occurs as nascent peptide chains elongate to a size of about 150 kilodaltons yielding a 32k protein and, upon chain completion, a 170k protein. this cleavage reaction is inhibited by 3 mm iodoacetamide. the 170k protein, in turn, is cleaved to yield either of two pairs of proteins, a 110k and 60k pair or a 87k and 84k pair. t ...	1984	6699013
cholesterolaemic action of vigna sinensis (cowpea).		1984	6706368
specificity of the actinomycin-d-sensitive function of some rna plant viruses.	the actinomycin-d(amd)-sensitive step of replication of three plant viruses - cowpea chlorotic mottle virus (ccmv), cowpea mosaic virus, and the cowpea strain of tobacco mosaic virus - in cowpea was specific for each virus. different combinations of the viruses were examined in which leaves were inoculated with one virus and incubated for 48 h until multiplication was almost resistant to amd. at that time, the same leaves were inoculated with a different virus and the ability of amd to inhibit m ...	1984	6735660
effects of increasing the fibre content of a layer diet.	the fibre content of a basal diet fed to laying hens was increased from 149.2 g to between 218.6 and 292.3 g/kg by the inclusion of various fibrous farm wastes and by-products at 200 g/kg diet. the fibrous ingredients lowered the metabolisable energy (me) of the basal diet from 11.82 to between 9.31 and 11.21 mj/kg. utilisation (g food/kg egg) of the basal diet was not significantly different from values for diets containing maize cob, cassava or maize starch residues. the diet containing maize ...	1984	6329485
preservation of rhizobium viability and symbiotic infectivity by suspension in water.	three rhizobium japonicum strains and two slow-growing cowpea-type rhizobium strains were found to remain viable and able to rapidly modulate their respective hosts after being stored in purified water at ambient temperatures for periods of 1 year and longer. three fast-growing rhizobium species did not remain viable under the same water storage conditions. after dilution of slow-growing rhizobium strains with water to 10(3) to 10(5) cells ml-1, the bacteria multiplied until the viable cell coun ...	1984	6378090
mobilization of a sym plasmid from a fast-growing cowpea rhizobium strain.	a large sym plasmid from a fast-growing cowpea rhizobium species was made mobilizable by cointegration with plasmid psup1011, which carries the orit region of rp4. this mobilizable sym plasmid was transferred to a number of rhizobium strains, in which nodulation and nitrogen fixation functions for symbiosis with plants of the cowpea group were expressed.	1984	6384201
similarity in gene organization and homology between proteins of animal picornaviruses and a plant comovirus suggest common ancestry of these virus families.	the amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus (cpmv), a plant virus, were compared. good homology was found between cpmv and the picornaviruses in the region of the picornavirus 2c (p2-x protein), vpg, 3c pro (proteinase) and 3d pol (rna polymerase) regions. the cpmv b genome was found to have a similar gene organization to the picornaviruses. a comparison of the 3c pro (proteinase) regions of all of the available picorn ...	1984	6384934
the responses of stomata and leaf gas exchange to vapour pressure deficits and soil water content : i. species comparisons at high soil water contents.	the responses of photosynthesis, transpiration and leaf conductance to changes in vapour pressure deficit were followed in well-watered plants of the herbaceous species, helianthus annuus, helianthus nuttallii, pisum sativum and vigna unguiculata, and in the woody species having either sclerophyllous leaves, arbutus unedo, nerium oleander and pistacia vera, or mesomorphic leaves, corylus avellana, gossypium hirsutum and prunus dulcis. when the vapour pressure deficit of the air around a single l ...	1984	28311208
comparison of water potentials measured by in situ psychrometry and pressure chamber in morphologically different species.	leaf water potentials measured by in situ psychrometry were compared with leaf water potentials measured by the pressure chamber technique at various values of water potential in helianthus annuus, helianthus nuttallii, vigna unguiculata, nerium oleander, pistacia vera, and corylus avellana. in v. unguiculata, the leaf water potentials measured by the in situ psychrometer oscillated at the same periodicity as, and proportional to, the leaf conductance. in all species, potentials measured by in s ...	1984	16663415
nickel in higher plants: further evidence for an essential role.	soybeans (glycine max [l.] merr.) grown in ni-deficient nutrient solutions accumulated toxic urea concentrations which resulted in necrosis of their leaflet tips, a characteristic of ni deficiency. estimates of the ni requirement of a plant were made by using seeds produced with different initial ni contents. when compared to soybeans grown from seeds containing 2.5 nanograms ni, plants grown from seeds containing 13 nanograms ni had a significantly reduced incidence of leaflet tip necrosis. pla ...	1984	16663907
rna-dependent rna polymerase isolated from cowpea chlorotic mottle virus-infected cowpeas is specific for bromoviral rna.	an rna-dependent rna polymerase activity capable of synthesizing full length double-stranded rna products only in the presence of bromoviral rna templates has been isolated from cowpea chlorotic mottle virus (ccmv)-infected cowpeas. no comparable discrete products were obtained when a nonbromoviral (cowpea mosaic virus) rna was used as template. heterodisperse, ribonuclease-sensitive products were obtained in reactions catalyzed by similar extracts from mock-inoculated (uninfected) plants in the ...	1984	18639798
the semipermeability of simple spherical virus capsids.	hydrogen-ion titration curves are reported for tomato bushy stunt virus, two strains of cowpea chlorotic mottle virus, and turnip crinkle virus, with particular attention to the hysteresis loops associated with the swelling and contraction of virions. there appears to be an archetypal shape of hysteresis loops, which is shared by viruses in several groups, suggestive of many intermediate states in the swelling of any one particle. in contrast, eggplant mosaic virus behaves as if its protein caps ...	1984	18639804
protein bound to the genome rnas of cowpea mosaic virus.		1984	215411
age dependence of cowpea protoplasts for uptake of spermidine and infectibility by alfalfa mosaic virus.	cowpea protoplasts were prepared from plants of different ages and examined for their ability to take up polyamines and for their infectibility by alfalfa mosaic virus. a lag period of ∼20 h was necessary before the onset of rapid polyamine uptake; the occurrence of this rapid uptake depended on the age of the leaves used for protoplast preparation. the percentage of infection of cowpea protoplasts by alfalfa mosaic virus, and the amount of virus produced also depended on the age of the plants u ...	1983	24318141
an alfalfa mosaic virus rna 2 mutant, which does not induce a hypersensitive reaction in cowpea plants, is multiplied to a high concentration in cowpea protoplasts.	a mutant of alfalfa mosaic virus (amv), which in contrast to wild type (wt) can invade cowpea plants systemically, is replicated more efficiently in cowpea protoplasts than the wt. mutant preparations isolated from infected cowpea protoplasts contained a higher amount of middle component (m, containing rna 2) than wt preparations. both in cowpea plants and in cowpea protoplasts a wt phenotype is obtained upon addition of wt m to this mutant, suggesting a correlation between the type of plant rea ...	1983	24318140
flow cytometric analysis of tobacco and cowpea protoplasts infected in vivo and in vitro with alfalfa mosaic virus.	immunofluorescence flow cytometry was used to study the distribution of viral antigen in protoplast populations. protoplasts were isolated from healthy and alfalfa mosaic virus (amv) infected tobacco leaves (designated in vivo infected). furthermore isolated tobacco and cowpea protoplasts were infected in vitro with amv. the fitc-conjugated antibodies could penetrate formaldehyde fixed protoplasts. the flow cytometric measurements were rapid and reproducible. comparable immunofluorescence patter ...	1983	24318100
ultrastructure of mixed plant virus infection: bean yellow mosaic virus with cowpea severe mosaic virus or cowpea mosaic virus in bean.	ultrastructural responses of bean leaf cells simultaneously infected with two morphologically distinct rna viruses, cowpea mosaic virus (cpmv) and bean yellow mosaic virus (bymv), or cowpea severe mosaic virus (csmv) and bymv, were studied in situ. the major effects on cells infected with two viruses included: (1) association of virus group-specific cytoplasmic inclusions characteristic of each virus; (2) close association of virions into specifically arranged aggregates in which cpmv or csmv ic ...	1983	18638866
replication of temperature-sensitive mutants of alfalfa mosaic virus in protoplasts.	six mutants of alfalfa mosaic virus (aimv), previously found to have conditionally lethal defects when inoculated to tobacco leaf discs, were assayed for a temperature-sensitive (ts) phenotype in cowpea protoplasts. at 30 degrees the virus production of four mutants was less than 10% of that obtained at 25 degrees , whereas wild-type aimv multiplied with similar efficiencies at both temperatures. supplementation experiments performed in protoplasts with two mutants indicated the presence of muta ...	1983	18638887
time course of alfalfa mosaic virus rna and coat protein synthesis in cowpea protoplasts.	a study was made of the time course of the synthesis of viral plus-strand rna, minus-strand rna, and coat protein in alfalfa mosaic virus-infected cowpea protoplasts. the three genomic rnas were synthesized at different rates, as were their corresponding minus-strands. we conclude that viral rna synthesis is regulated both at the level of minus-strand production and the level of plus-strand production. the synthesis of subgenomic rna 4 was slower than that of its corresponding genomic rna (rna 3 ...	1983	18638888
the self-assembly of the cowpea strain of southern bean mosaic virus: formation of t = 1 and t = 3 nucleoprotein particles.	virion-like particles of the cowpea strain of southern bean mosaic virus were assembled from isolated coat protein and rna components in vitro at low ionic strength. purified southern bean mosaic virus rna was heterogeneous on sucrose gradients, and was separated into low (0.3 - 0.6 x 10(6) da) and high (1.0-1.4 x 10(6) da) molecular weight (mw) fractions. assembly with high mw rna resulted in t = 3 particles at ph 7 and 9. low mw rna assembled with coat protein into t = 1 particles at ph 5 and ...	1983	18638938
nucleotide sequence of the coat protein cistron and the 3' noncoding region of cucumber green mottle mosaic virus (watermelon strain) rna.	double-stranded cdna copies of cucumber green mottle mosaic virus (watermelon strain, cgmmv-w) rna polyadenylated in vitro were cloned into the pbr322 at the psti site. the sequence of 1071 nucleotides from the tend of the genomic rna was determined using two recombinant plasmids and the genomic rna. the coat protein cistron was located in residues 176-661 from the 3' end. the coat protein was composed of 160 amino acid residues with the molecular weight of 17,261. the 3' noncoding region of the ...	1983	18638996
orientation of the cleavage map of the 200-kilodalton polypeptide encoded by the bottom-component rna of cowpea mosaic virus.	the genomic organization of the bottom-component rna of cowpea mosaic virus was studied. in vivo, this rna encodes at least eight different polypeptides of 170, 110, 87, 84, 60, 58, 32, and 4 kilodaltons (k), the last polypeptide representing the genome-bound protein vpg. in rabbit reticulocyte lysates, bottom-component rna is translated into a 200k polypeptide which is then processed to give the 32 and 170k polypeptides also found in vivo. by pulse-labeling the 200k primary translation product, ...	1983	16789243
altered balance of the synthesis of plus- and minus-strand rnas induced by rnas 1 and 2 of alfalfa mosaic virus in the absence of rna 3.	the synthesis of viral plus-strand and minus-strand rnas in cowpea protoplasts inoculated with mixtures of alfalfa mosaic virus nucleoproteins (b, m, tb, and ta) was analyzed by the northern blotting technique. a mixture of b, m, and tb induced the synthesis of plus-strand rnas 1, 2, 3, and 4 and three minus-strand rnas corresponding to rnas 1, 2, and 3, respectively. compared to this complete infection, a mixture of b and m induced the synthesis of a reduced amount of plus-strand rnas 1 and 2 a ...	1983	18644274
specialized cellular arrangements in legume leaves in relation to assimilate transport and compartmentation: comparison of the paraveinal mesophyll.	leaves of eight species of leguminosae-papilionoideae were examined for the presence of a highly specialized cell layer called the paraveinal mesophyli (pvm). three species, glycine max (l.) merr, psophocarpus tetragonolobus d.c. and vigna radiata l., contained pvm; five (medicago sativa l., phaseolus vulgaris l., pisum sativum l., vicia faba l., vigna unguiculata l.) did not. the pvm of g. max and p. tetragonolobus was anatomically identical and consisted of large, interconnected, multiarmed ce ...	1983	24258294
conservation in soil of h(2) liberated from n(2) fixation by hup nodules.	pigeon peas (cajanus cajan) were grown in large soil columns (90-cm length by 30-cm diameter) and inoculated with four different strains of cowpea rhizobia, which varied with respect to hydrogen uptake activity (hup). despite the profuse liberation of h(2) from hup nodules in vitro, h(2) gas was not detected in any of the soil columns. when h(2) was injected into the columns, the rates of consumption were highest in the treatments (including control) containing hup nodules (218 and 177 nmol . h ...	1983	16346356
validation of a model for prediction of host damage by two nematode species.	plant roots were mechanically injured or subjected to nematode parasitism to test the model of host damage by two nematode species: y = m' + (l - m')c'z(p)z(p) for y </= 1.0 and y = 1.0 for y > 1.0, where m' = m + (m - m) (1 - y)/[(1 - y) + (l - y)] and c' = (z(-t) + z(-t))/2. damage functions for greenhouse-grown radish plants (cv. cherry belle) mechanically injured with small or large steel needles were used to predict growth of plants injured by both needles. growth predictions accounted for ...	1983	19295796
relationships among rhizobia from native australian legumes.	isolates from 12 legumes at three sites in victoria showed a wide range of morphological, cultural, symbiotic, and serological properties. isolates from acacia longifolia var. sophorae and kennedia prostrata were fast growing but nodulated ineffectively macroptilium atropurpureum and all native legumes except swainsonia lessertiifolia. isolates from s. lessertiifolia showed anomalous properties intermediate between fast- and slow-growing rhizobia. all isolates from the other two sites were slow- ...	1983	16346315
aspergillus infection and aflatoxin production in some cowpea (vigna unguiculata (l.) walp) lines in tanzania.	seeds of twenty-two cowpea (vigna unguiculata (l.) walp) lines/cultivars were inoculated with aspergillus parasiticus (link) (nrrl 3145) and aflatoxin production was evaluated. all the cowpea samples were susceptible to aspergillus infection and subsequent aflatoxin production. the amount of aflatoxin produced ranged between 466.6 micrograms/kg to 1 806 micrograms/kg in the case of b (b1 + b2) and 20.8 micrograms/kg to 82.7 micrograms/kg of seed in the case of g (g1 + g2). on the basis of the am ...	1983	6422301
pleomorphism and acetylene-reducing activity of free-living rhizobia.	cowpea-type rhizobium sp. strain 32h1 and rhizobium japonicum usda 26 and 110 grown on a glutamate-mannitol-gluconate agar medium showed increases in the number of pleomorphic cells coincident with their acetylene-reducing activity. pleomorphs appeared to be inhibited in growth nonuniformly, because acetylene-reducing cultures were mixtures of rod, branched (v, y, and t), and other irregularly shaped cells. in contrast, strain usda 10 consistently failed to reduce acetylene, even though it also ...	1983	6822472
methylammonium uptake by rhizobium sp. strain 32h1.	we present evidence that methylammonium is transported into cowpea rhizobium sp. strain 32h1 cells by a membrane carrier whose natural substrate is ammonium. after growth in low (0.2%) oxygen, which is necessary for nitrogen fixation by these cells, respiring rhizobial cells took up [14c]methylammonium to high intracellular levels. cells grown in atmospheric (21%) oxygen did not take up methylammonium. uptake (transport plus metabolism) was maximal in cells harvested in the early stationary phas ...	1983	6826521
multiple proteins and subgenomic mrnas may be derived from a single open reading frame on tobacco mosaic virus rna.	it has previously been shown that messenger activity for a protein of mr = ca. 30k exists in rna fractions extracted from particles of either native or alkali stripped u1 tmv, or from cowpea strain tmv, that are smaller than full genomic length. analysis of sucrose gradient fractions containing this activity reveals a number of slightly smaller template activities directing synthesis of proteins between 18.5k and 29k in size. all of these messenger activities, including that for the 30k protein, ...	1983	6835837
characterization of a lectin from cowpeas.	a lectin without blood group specificity was isolated from cowpeas (vigna unguiculata (l.) walp.). this lectin was prepared from a crude saline extract by acid precipitation and sephadex gel filtration. purification steps generally resulted in increased agglutination activity. homogeneity was demonstrated by polyacrylamide gel electrophoresis, and ultracentrifugation. the native lectin had a molecular weight of approximately 55,000 as shown by gel filtration, polyacrylamide electrophoresis, and ...	1983	6856584
inhibition of alfalfa mosaic virus rna and protein synthesis by actinomycin d and cycloheximide.	actinomycin d, added early after inoculation, reduces the production of infectious alfalfa mosaic virus in cowpea protoplasts by 90%. this reduction was associated with an inhibition of viral minus-strand and plus-strand rna synthesis, suggesting the involvement of host factors in these processes. coat protein production was less affected by the drug. addition of cycloheximide throughout the growth cycle resulted in an immediate cessation of coat protein production and an enhanced degradation of ...	1983	6857995