Sample records for leucaena leucaena leucocephala

  1. Lime-aluminium-phosphorus interactions and the growth of Leucaena leucocephala

    Microsoft Academic Search

    R. Naidu; R. W. Tillman; J. K. Syers; J. H. Kirkman

    1990-01-01

    The effects of lime and P on the chemical composition of the tropical legume Leucaena leucocephala were studied in a controlled climate laboratory experiment using 4 (Koronivia, Nadroloulou, Batiri, and Seqaqa) highly-weathered, acid soils from Fiji. For all soils, changes in the concentration of P in the Leucaena tops followed trends similar to the yield response curve, i.e., the concentration

  2. Feed intake, sperm output and seminal characteristics of Ethiopian highland sheep supplemented with different levels of leucaena ( Leucaena leucocephala) leaf hay

    Microsoft Academic Search

    Negussie Dana; Azage Tegegne; Teshome Shenkoru

    2000-01-01

    The effect of feeding increasing levels of Leucaena leucocephala leaf hay on the potential fertility and feed intake of male highland sheep maintained on roughage diet was studied. In treatment 1 (NS), animals received only chickpea haulm. Treatments 2 (L100), 3 (L200) and 4 (L300) consisted of 100, 200 and 300g per head per day of sun dried leucaena leaf

  3. Improved method of in vitro regeneration in Leucaena leucocephala - a leguminous pulpwood tree species.

    PubMed

    Shaik, Noor M; Arha, Manish; Nookaraju, A; Gupta, Sushim K; Srivastava, Sameer; Yadav, Arun K; Kulkarni, Pallavi S; Abhilash, O U; Vishwakarma, Rishi K; Singh, Somesh; Tatkare, Rajeshri; Chinnathambi, Kannan; Rawal, Shuban K; Khan, Bashir M

    2009-10-01

    Leucaena leucocephala is a fast growing multipurpose legume tree used for forage, leaf manure, paper and pulp. Lignin in Leucaena pulp adversely influences the quality of paper produced. Developing transgenic Leucaena with altered lignin by genetic engineering demands an optimized regeneration system. The present study deals with optimization of regeneration system for L. leucocephala cv. K636. Multiple shoot induction from the cotyledonary nodes of L. leucocephala was studied in response to cytokinins, thidiazuron (TDZ) and N(6)-benzyladenine (BA) supplemented in half strength MS (½-MS) medium and also their effect on in vitro rooting of the regenerated shoots. Multiple shoots were induced from cotyledonary nodes at varied frequencies depending on the type and concentration of cytokinin used in the medium. TDZ was found to induce more number of shoots per explant than BA, with a maximum of 7 shoots at an optimum concentration of 0.23 µM. Further increase in TDZ concentration resulted in reduced shoot length and fasciation of the shoots. Liquid pulse treatment of the explants with TDZ did not improve the shoot production further but improved the subsequent rooting of the shoots that regenerated. Regenerated shoots successfully rooted on ½-MS medium supplemented with 0.54 µM ?-naphthaleneacetic acid (NAA). Rooted shoots of Leucaena were transferred to coco-peat and hardened plantlets showed ? 90 % establishment in the green house. PMID:23572941

  4. Development of an Agrobacterium-mediated transformation protocol for the tree-legume Leucaena leucocephala using immature zygotic embryos

    PubMed Central

    Jube, Sandro

    2009-01-01

    The tree-legume Leucaena leucocephala (leucaena) is used as a perennial fodder because of its fast-growing foliage, which is high in protein content. The use of leucaena as a fodder is however restricted due to the presence of the toxin mimosine. Improvements in the nutritional contents as well as other agronomic traits of leucaena can be accomplished through genetic transformation. The objective of this research was to develop a transformation protocol for leucaena using phosphinothricin resistance as the plant selectable marker. Explants obtained from immature zygotic embryos infected with the Agrobacterium tumefaciens strain C58C1 containing the binary plasmid pCAMBIA3201 produced four putative transformed leucaena plants. Transformation was con- firmed by PCR, RT-PCR, Southern blot, Western analyses, GUS-specific enzyme activity and herbicide leaf spraying assay. A transformation efficiency of 2% was established using this protocol. PMID:20041041

  5. Vesicular arbuscular mycorrhizal fungi improves establishment of micropropagated Leucaena leucocephala plantlets

    Microsoft Academic Search

    Jos T. Puthur; K. V. S. K. Prasad; P. Pardha Saradhi

    1998-01-01

    Investigations were carried out to achieve cent per cent transplantation success of micropropagated Leucaena leucocephala\\u000a (a fast growing multipurpose leguminous tree species) plantlets using two vesicular arbuscular mycorrhizal fungi, Glomus fasciculatum\\u000a and Glomus macrocarpum. Plantlets were obtained by rooting the shoots [obtained through; hypocotyl callus in presence of 10-5M BAP + 10-6M NAA; and axillary bud sprouting from cotyledonary and

  6. Leucaena leucocephala Fruit Aqueous Extract Stimulates Adipogenesis, Lipolysis, and Glucose Uptake in Primary Rat Adipocytes

    PubMed Central

    Kuppusamy, Umah Rani; Azaman, Nooriza; Jen Wai, Chai

    2014-01-01

    Leucaena leucocephala had been traditionally used to treat diabetes. The present study was designed to evaluate in vitro “insulin-like” activities of Leucaena leucocephala (Lam.) deWit. aqueous fruit extract on lipid and glucose metabolisms. The ability of the extract to stimulate adipogenesis, inhibit lipolysis, and activate radio-labeled glucose uptake was assessed using primary rat adipocytes. Quantitative Real-Time RT-PCR was performed to investigate effects of the extract on expression levels of genes (protein kinases B, AKT; glucose transporter 4, GLUT4; hormone sensitive lipase, HSL; phosphatidylinositol-3-kinases, PI3KA; sterol regulatory element binding factor 1, Srebp1) involved in insulin-induced signaling pathways. L. leucocephala aqueous fruit extract stimulated moderate adipogenesis and glucose uptake into adipocytes when compared to insulin. Generally, the extract exerted a considerable level of lipolytic effect at lower concentration but decreased gradually at higher concentration. The findings concurred with RT-PCR analysis. The expressions of GLUT4 and HSL genes were upregulated by twofold and onefold, respectively, whereas AKT, PI3KA, and Srebp1 genes were downregulated. The L. leucocephala aqueous fruit extract may be potentially used as an adjuvant in the treatment of Type 2 diabetes mellitus and weight management due to its enhanced glucose uptake and balanced adipogenesis and lipolysis properties. PMID:25180205

  7. Decomposition and nitrogen-mineralization patterns of Leucaena leucocephala and Cassia siamea mulch under tropical semiarid conditions in Kenya

    Microsoft Academic Search

    B. A. Jama; P. K. R. Nair

    1996-01-01

    In agroforestry systems, loppings from trees and shrubs are commonly used, often as mulch, as sources of nutrients for interplanted crops. Therefore, it is important to understand the rates of mulch decomposition. This paper reports the results of a study on the decomposition and nitrogen (N)-mineralization patterns of the leaves, small twigs, and mulch (leaves plus twigs) of Leucaena leucocephala

  8. Cinnamate 4-Hydroxylase (C4H) genes from Leucaena leucocephala: a pulp yielding leguminous tree.

    PubMed

    Kumar, Santosh; Omer, Sumita; Patel, Krunal; Khan, Bashir M

    2013-02-01

    Leucaena leucocephala is a leguminous tree species accounting for one-fourth of raw material supplied to paper and pulp industry in India. Cinnamate 4-Hydroxylase (C4H, EC 1.14.13.11) is the second gene of phenylpropanoid pathway and a member of cytochrome P450 family. There is currently intense interest to alter or modify lignin content of L. leucocephala. Three highly similar C4H alleles of LlC4H1 gene were isolated and characterized. The alleles shared more than 98 % sequence identity at amino acid level to each other. Binding of partial promoter of another C4H gene LlC4H2, to varying amounts of crude nuclear proteins isolated from leaf and stem tissues of L. leucocephala formed two loose and one strong complex, respectively, suggesting that the abundance of proteins that bind with the partial C4H promoter is higher in stem tissue than in leaf tissue. Quantitative Real Time PCR study suggested that among tissues of same age, root tissues had highest level of C4H transcripts. Maximum transcript level was observed in 30 day old root tissue. Among the tissues investigated, C4H activity was highest in 60 day old root tissues. Tissue specific quantitative comparison of lignin from developing seedling stage to 1 year old tree stage indicated that Klason lignin increased in tissues with age. PMID:23070917

  9. Use of the legume tree crops Gliricidia sepium and Leucaena leucocephala as green feeds for growing rabbits

    Microsoft Academic Search

    O. C. Onwudike

    1995-01-01

    A total of 157 New Zealand White rabbits were used in three separate experiments to determine the performance of growing rabbits which received leaves of the browse plants —Gliricidia sepium andLeucaena leucocephala as green feeds. Feeding of gliricidia allowed for the daily consumption of 65.1 g of pelleted concentrates and this was significantly (P < 0.05) higher than the pellet

  10. Prospective Application of Leucaena Leucocephala for Phytoextraction of Cd and Zn and Nitrogen Fixation in Metal Polluted Soils

    Microsoft Academic Search

    Shweta Saraswat; J. P. N. Rai

    2011-01-01

    The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced

  11. Productivity of alley farming with leucaena ( Leucaena leucocephala Lam. de Wit) and Napier grass ( Pennisetum purpureum K. Schum) in coastal lowland Kenya

    Microsoft Academic Search

    J. G. Mureithi; R. S. Tayler; W. Thorpe

    1995-01-01

    Inadequate supply of fodder is a serious constraint to the potentially-promising small-holder-dairy production system in coastal Kenya. Alley farming could be an approach to addressing this problem. A study of forage production based on Napier grass and leucaena in an alley cropping system was conducted on an infertile sandy soil in lowland coastal Kenya. The effects of leucaena hedgerows,Clitoria ternatea

  12. Biorefinery process for production of paper and oligomers from Leucaena leucocephala K360 with or without prior autohydrolysis.

    PubMed

    Feria, M J; García, J C; Díaz, M J; Fernández, M; López, F

    2012-12-01

    Lignocellulosic material from Leucaena leucocephala was subjected to a two-stage fractionation process to obtain a valorized effluent containing hemicellulose derivatives and a solid phase for producing cellulose pulp by conventional soda-anthraquinone delignification. This solid phase allows the production of cellulose pulp, under less rigorous conditions from NaOH-AQ process (177 °C, 21%, 120 min) than without pretreatment delignification (185 °C, 25%, 150 min) and better or similar properties in the paper sheets obtained (yield 27.6 and 34.0%, brightness 39.3 and 31.6% ISO, tensile index 7.8 and 10.5 N m/g, burst index 0.43 and 0.29 MPa m(2)/kg with and without previous autohydrolysis) have be found. Also, the first autohydrolysis stage allows up to 46.6% of the initial hemicellulose in the raw material to be extracted as xylooligomers, xylose and furfural into the liquid phase. PMID:23073090

  13. Leucaena leucocephala serine proteinase inhibitor: primary structure and action on blood coagulation, kinin release and rat paw edema 1 1 Dedicated to Prof. Hans Neurath

    Microsoft Academic Search

    Maria Luiza V Oliva; Jose Carlos Souza-Pinto; Isabel F. C Batista; Mariana S Araujo; Vera F Silveira; Ennes A Auerswald; Reini Mentele; Christoph Eckerskorn; Misako U Sampaio; Claudio A. M Sampaio

    2000-01-01

    A serine proteinase inhibitor isolated from Leucaena leucocephala seeds (LlTI) was purified to homogeneity by acetone fractionation, ion exchange chromatography, gel filtration and reverse phase chromatography (HPLC). SDS-PAGE indicated a protein with Mr 20?000 and two polypeptide chains (?-chain, Mr 15?000, and ?-chain, Mr 5000), the sequence being determined by automatic Edman degradation and by mass spectroscopy. LlTI is a

  14. Palatability and effect on dairy cow milk yield of dried fodder from the forage trees Acacia boliviana, Calliandra calothyrsus and Leucaena leucocephala

    Microsoft Academic Search

    B. V Maasdorp; V Muchenje; M Titterton

    1999-01-01

    Four groups of three Holstein–Friesian cows were supplemented with 1.5kg of air-dried tree fodder of Acacia boliviana, Calliandra calothyrsus or Leucaena leucocephala, or 1.5kg Rhodes grass hay as a control, mixed with 5g of a commercial polyethylene glycol (PEG)-containing digestive modifier (Browse Plus). Cows on all treatments were fed a basal diet of maize silage, cottonseed cake and crushed maize

  15. Allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala on three selected weed species

    NASA Astrophysics Data System (ADS)

    Ishak, Muhamad Safwan; Sahid, Ismail

    2014-09-01

    A laboratory experiment was conducted to study the allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala. The aqueous extracts were individually tested on three selected weed species, namely goatweed (Ageratum conyzoides), coat buttons (Tridax procumbens) and lilac tasselflower (Emilia sonchifolia). The allelopathic effects of the leaf and seed extracts on germination, shoot length, root length and fresh weight of each of the selected weed species were determined. Germination of goatweed, coat buttons and lilac tasselflower were inhibited by the aqueous extracts of both the leaf and seed of L. leucocephala and was concentration dependent. Different concentrations of the aqueous extracts showed various germination patterns on the selected weeds species. Seedling length and fresh weight of goatweed, coat buttons and lilac tasselflower were reduced in response to respective increasing concentrations of the seed extracts. Maximum inhibition by the aqueous seed extract was observed more on the root rather than the shoot growth. The aqueous seed extract at T3 concentration reduced root length of goatweed, coat buttons and lilac tasselflower by 95%, 86% and 91% (of the control) respectively. The aqueous seed extract showed greater inhibitory effects than that of the aqueous leaf extract.

  16. Variations in fiber length and some pulp chemical properties of Leucaena varieties

    Microsoft Academic Search

    M. J. Díaz; M. M. García; M. E. Eugenio; R. Tapias; M. Fernández; F. López

    2007-01-01

    To identify non-wood fast-growing species utilizable for pulp and paper production six Leucaena varieties were tested. Concurrently, these species were also tested for suitability as pulp materials on a laboratory scale. Biomass productivity of three Leucaena varieties (Leucaena diversifolia, Leucaena collinsii and Leucaena leucocephala) studied ranges from 67.14 to 9.44tha?1 (o.d.b.) under Mediterranean conditions for the year first sprouts. The

  17. Probing the active site of cinnamoyl CoA reductase 1 (Ll-CCRH1) from Leucaena leucocephala.

    PubMed

    Sonawane, Prashant; Patel, Krunal; Vishwakarma, Rishi Kishore; Srivastava, Sameer; Singh, Somesh; Gaikwad, Sushama; Khan, Bashir M

    2013-09-01

    Lack of three dimensional crystal structure of cinnamoyl CoA reductase (CCR) limits its detailed active site characterization studies. Putative active site residues involved in the substrate/NADPH binding and catalysis for Leucaena leucocephala CCR (Ll-CCRH1; GenBank: DQ986907) were identified by amino acid sequence alignment and homology modeling. Putative active site residues and proximal H215 were subjected for site directed mutagenesis, and mutated enzymes were expressed, purified and assayed to confirm their functional roles. Mutagenesis of S136, Y170 and K174 showed complete loss of activity, indicating their pivotal roles in catalysis. Mutant S212G exhibited the catalytic efficiencies less than 10% of wild type, showing its indirect involvement in substrate binding or catalysis. R51G, D77G, F30V and I31N double mutants showed significant changes in Km values, specifying their roles in substrate binding. Finally, chemical modification and substrate protection studies corroborated the presence Ser, Tyr, Lys, Arg and carboxylate group at the active site of Ll-CCRH1. PMID:23688416

  18. Estimating Apparent Nutrient Digestibility of Diets Containing Leucaena leucocephala or Moringa oleifera Leaf Meals for Growing Rabbits by Two Methods.

    PubMed

    Safwat, A M; Sarmiento-Franco, L; Santos-Ricalde, R H; Nieves, D; Sandoval-Castro, C A

    2015-08-01

    This study aimed to evaluate the nutrient digestibility of growing rabbits fed diets with different levels of either Leucaena leucocephala (LLM) or Moringa oleifera (MOLM) leaf meals and also to compare total collection and TiO2 marker methods for estimating digestibility. A total of 30 California growing rabbits (1.81±0.19 kg live weight on average) were randomly distributed into five experimental groups of six rabbits each and were housed in individual cages. The groups were control, 30% LLM, 40% LLM, 30% MOLM, and 40% MOLM. All groups received pelleted diets for two weeks; diets also contained 4 g/kg titanium dioxide as dietary marker. Daily feed intake was recorded during the whole experimental period and total feces were collected daily and weighed individually during four days. The results showed that there were no difference (p>0.05) in feed, dry matter (DM), organic matter (OM), crude protein (CP), digestible energy, and crude fiber (CF) intake between the control group and the other experimental groups. The apparent digestibility values of DM, OM, CP, CF, acid detergent fiber, and gross energy were the highest for control group (p = 0.001), meanwhile MOLM diets had generally higher nutrient digestibility coefficients than LLM diets. Increasing the inclusion level of leaf meal in the diet from 30% to 40% improved the digestibility of CF from 45.02% to 51.69% for LLM and from 48.11% to 55.89% for MOLM. Similar results for apparent nutrient digestibility coefficients were obtained when either total collection or indigestible marker method was used. In conclusion, the digestibility of MOLM containing diets were better than LLM diets, furthermore TiO2 as an external marker could be used as a simple, practical and reliable method to estimate nutrients digestibility in rabbit diets. PMID:26104524

  19. Expression analysis of cinnamoyl-CoA reductase (CCR) gene in developing seedlings of Leucaena leucocephala: a pulp yielding tree species.

    PubMed

    Srivastava, Sameer; Gupta, Ranadheer K; Arha, Manish; Vishwakarma, Rishi K; Rawal, Shuban K; Kavi Kishor, P B; Khan, Bashir M

    2011-02-01

    Removal of lignin is a major hurdle for obtaining good quality pulp. Leucaena leucocephala (subabul) is extensively used in paper industry in India; therefore, as a first step to generate transgenic plants with low lignin content, cDNA and genomic clones of CCR gene were isolated and characterized. The cDNA encoding CCR (EC 1.2.1.44) was designated as Ll-CCR; the sequence analysis revealed an Open Reading Frame (ORF) of 1005 bp. Phylogenetic analysis showed that Ll-CCR sequence is highly homologous to CCRs from other dicot plants. The 2992 bp genomic clone of Leucaena CCR consists of 5 exons and 4 introns. The haploid genome of L. leucocephala contains two copies as revealed by DNA blot hybridization. Ll-CCR gene was over-expressed in Escherichia coli, which showed a molecular mass of approximately 38 kDa. Protein blot analysis revealed that Ll-CCR protein is expressed at higher levels in root and in stem, but undetectable in leaf tissues. Expression of CCR gene in Leucaena increased up to 15 d in case of roots and stem as revealed by QRT-PCR studies in 0-15 d old seedlings. ELISA based studies of extractable CCR protein corroborated with QRT-PCR data. CCR protein was immuno-cytolocalized around xylem tissue. Lignin estimation and expression studies of 5, 10 and 15 d old stem and root suggest that CCR expression correlates with quantity of lignin produced, which makes it a good target for antisense down regulation for producing designer species for paper industry. PMID:21123078

  20. Over-expression of a subgroup 4 R2R3 type MYB transcription factor gene from Leucaena leucocephala reduces lignin content in transgenic tobacco.

    PubMed

    Omer, Sumita; Kumar, Santosh; Khan, Bashir M

    2013-01-01

    KEY MESSAGE : LlMYB1 , a subgroup 4 R2R3-type MYB transcription factor gene from Leucaena leucocephala appears to be a repressor of lignin biosynthesis pathway by regulating the transcription of general phenylpropanoid pathway genes. R2R3MYB transcription factors are known to play a wide role in regulating the phenylpropanoid pathway in plants. In this study, we report isolation, cloning and characterization of an R2R3MYB transcription factor gene (LlMYB1) from an economically important tree species, Leucaena leucocephala. LlMYB1 consists of 705 bp coding sequence corresponding to 235 amino acids. Sequence alignment revealed that the N-terminal (MYB) domain of the gene shares up to 95 % similarity with subgroup 4 (Sg4) members of R2R3Myb gene family functionally known to be lignin repressors. Highly divergent C-terminal region of the gene carried an ERF-associated amphiphilic repression (EAR) motif, another characteristic of the Sg4. The gene was phylogenetically grouped closest with AmMYB308, a known repressor of monolignol biosynthetic pathway genes. Spatio-temporal expression studies at different ages of seedlings using quantitative real-time PCR (QRT-PCR) showed highest transcript level of the gene in 10 day old stem tissues. Over-expression of the gene in transgenic tobacco showed statistically significant decline in the transcript levels of the general phenylpropanoid pathway genes and reduction in lignin content. Our study suggests that LlMYB1 might be playing the role of a repressor of lignin biosynthesis in L. leucocephala. PMID:23052594

  1. High-resolution transcriptomic analyses of Sinorhizobium sp. NGR234 bacteroids in determinate nodules of Vigna unguiculata and indeterminate nodules of Leucaena leucocephala.

    PubMed

    Li, Yan; Tian, Chang Fu; Chen, Wen Feng; Wang, Lei; Sui, Xin Hua; Chen, Wen Xin

    2013-01-01

    The rhizobium-legume symbiosis is a model system for studying mutualistic interactions between bacteria and eukaryotes. Sinorhizobium sp. NGR234 is distinguished by its ability to form either indeterminate nodules or determinate nodules with diverse legumes. Here, we presented a high-resolution RNA-seq transcriptomic analysis of NGR234 bacteroids in indeterminate nodules of Leucaena leucocephala and determinate nodules of Vigna unguiculata. In contrast to exponentially growing free-living bacteria, non-growing bacteroids from both legumes recruited several common cellular functions such as cbb3 oxidase, thiamine biosynthesis, nitrate reduction pathway (NO-producing), succinate metabolism, PHB (poly-3-hydroxybutyrate) biosynthesis and phosphate/phosphonate transporters. However, different transcription profiles between bacteroids from two legumes were also uncovered for genes involved in the biosynthesis of exopolysaccharides, lipopolysaccharides, T3SS (type three secretion system) and effector proteins, cytochrome bd ubiquinol oxidase, PQQ (pyrroloquinoline quinone), cytochrome c550, pseudoazurin, biotin, phasins and glycolate oxidase, and in the metabolism of glutamate and phenylalanine. Noteworthy were the distinct expression patterns of genes encoding phasins, which are thought to be involved in regulating the surface/volume ratio of PHB granules. These patterns are in good agreement with the observed granule size difference between bacteroids from L. leucocephala and V. unguiculata. PMID:23936444

  2. Evaluation of herbicides for use in transplanting leucaena leucocephala and prosopis alba on semi-arid lands without irrigation

    SciTech Connect

    Felker, P.; Smith, D.; Smith, M.; Bingham, R.L.; Reyes, I.

    1984-01-01

    Five herbicides were applied to plots at 2 rates in April 1982, and 3-month old seedlings planted 2 days later. Basal diameter was measured after 110 days and converted to dry weight using published equations. Percent weed cover was recorded 45, 75, and 105 days after planting. All herbicides increased survival over untreated controls. The greatest biomass production of both species was obtained with oryzalin treatment at 2.8 kg/ha active ingredient, which increased production 4-5X compared with control plots. Oryzalin was second to napropamide (2.24 kg/ha active ingredient) in grass control and equal to oxyfluorfen (1.12 kg/ha active ingredient) in forb control, oxyfluorfen at this rate also gave the second best biomass production. Oryzalin increased survival from 71 to 87% for Leucaena and from 81-94% for Prosopis, and is considered to be the best herbicide tested, followed by oxyfluorfen and metolachlor. Alachlor was considered to be too short-lived and napropamide too expensive.

  3. nodSU, two new nod genes of the broad host range Rhizobium strain NGR234 encode host-specific nodulation of the tropical tree Leucaena leucocephala.

    PubMed

    Lewin, A; Cervantes, E; Chee-Hoong, W; Broughton, W J

    1990-01-01

    Rhizobium species strain NGR234 nodulates at least 35 diverse genera of legumes as well as the nonlegume Parasponia andersonii. Most nodulation genes are located on the 500-kilobase pair symbiotic plasmid, pNGR234a. Previously, three plasmid-borne host range determinants (HsnI, HsnII, and HsnIII) were identified by their ability to extend the nodulation capacity of heterologous rhizobia to include Vigna unguiculata. In this study, we show that HsnII contains two new nod-box linked hsn genes, nodS and nodU.nodS controls nodulation of the tropical tree Leucaena leucocephala, while the nodSU genes regulate nodulation of the pasture legume Desmodium intortum and the grain legume V. unguiculata. Regulation of the nod-box upstream of nodSU by the flavonoid naringenin was shown using a fusion with a promoterless lacZ gene. Determination of the nucleotide sequence of the nodS gene did not reveal homology with any gene in the EMBL library, although Bradyrhizobium japonicum USDA110 contains both nodS and nodU (M. Göttfert, S. Hitz, and H. Hennecke, Molecular Plant-Microbe Interactions 3:308-316, 1990). We suggest that broad host range in NGR234 is controlled in part by a nodD gene which interacts with a wide range of flavonoids, and in part by host-specific nod genes such as nodS. PMID:2134856

  4. Down-regulation of Leucaena leucocephala cinnamoyl CoA reductase (LlCCR) gene induces significant changes in phenotype, soluble phenolic pools and lignin in transgenic tobacco.

    PubMed

    Prashant, S; Srilakshmi Sunita, M; Pramod, S; Gupta, Ranadheer K; Anil Kumar, S; Rao Karumanchi, S; Rawal, S K; Kavi Kishor, P B

    2011-12-01

    cDNA and genomic clones of cinnamoyl CoA reductase measuring 1011 and 2992 bp were isolated from a leguminous pulpwood tree Leucaena leucocephala, named as LlCCR. The cDNA exhibited 80-85% homology both at the nucleotide and amino acid levels with other known sequences. The genomic sequence contained five exons and four introns. Sense and antisense constructs of LlCCR were introduced in tobacco plants to up and down-regulate this key enzyme of lignification. The primary transformants showed a good correlation between CCR transcript levels and its activity. Most of the CCR down-regulated lines displayed stunted growth and development, wrinkled leaves and delayed senescence. These lines accumulated unusual phenolics like ferulic and sinapic acids in cell wall. Histochemical staining suggested reduction in aldehyde units and increased syringyl over guaiacyl (S/G) ratio of lignin. Anatomical studies showed thin walled, elongated xylem fibres, collapsed vessels with drastic reduction of secondary xylem. The transmission electron microscopic studies revealed modification of ultrastructure and topochemical distribution of wall polysaccharides and lignin in the xylem fibres. CCR down-regulated lines showed increased thickness of secondary wall layers and poor lignification of S2 and S3 wall layers. The severely down-regulated line AS17 exhibited 24.7% reduction of Klason lignin with an increase of 15% holocellulose content. Contrarily, the CCR up-regulated lines exhibited robust growth, development and significant increase in lignin content. The altered lignin profiles observed in transgenic tobacco lines support a role for CCR down-regulation in improving wood properties of L. leucocephala exclusively used in the pulp and paper industry of India. PMID:21847621

  5. Leucaena forage analysis using near infrared reflectance spectroscopy

    Microsoft Academic Search

    Robert A. Wheeler; William R. Chaney; Keith D. Johnson; Larry G. Butler

    1996-01-01

    Leucaena is a fast growing, multipurpose tree planted in tropical regions for many uses including forage. Leaf and leaf + stem material were collected from Leucaena species, varieties, and hybrids grown at two sites in Hawaii and in Australia. Neutral detergent fiber, acid detergent fiber, crude protein, in-vitro dry matter digestibility, and relative condensed tannin were determined by both laboratory

  6. Leucaena and tall grasses as energy crops in humid lower south USA

    SciTech Connect

    Prine, G.M.; Woodard, K.R. [Univ. of Florida, Gainesville, FL (United States); Cunilio, T.V. [Center of Sustainable Argoforesty, Gainesville, FL (United States)

    1994-12-31

    The tropical leguminous shrub/tree, leucaena (Leucaena spp. mainly leucocephala), and perennial tropical tall grasses such as elephantgrass (Pennisetum purpureum), sugarcane, and energycane (Saccharum spp.) are well adapted to the long growing seasons and high rainfall of the humid lower South. In much of the area the topgrowth is killed by frost during winter and plants regenerate from underground parts in spring. Selected accessions from a duplicated 373 accession leucaena nursery had an average annual woody stem dry matter production of 31.4 Mg ha{sup -1}. Average oven dry stem wood yields from selected accessions adjusted for environmental enrichment over the 4 growth seasons were 78.9 Mg ha{sup -1} total and average annual yield of 19.7 Mg ha{sup -1}. The tall perennial grasses have linear growth rates of 18 to 27 g m{sup 2}d{sup -1} for long periods (140 to 196 d and sometimes longer) each season. Oven dry biomass yields of tall grasses have varied from 20 to 45 Mg ha{sup -1} in mild temperature locations to over 60 Mg ha{sup -1} yr{sup -1} in warm subtropics of the lower Florida peninsula. Tall grasses and leucaena, once established, may persist for many seasons. A map showing the possible range of the crops in lower South is shown. Highest biomass yields of tall grasses have been produced when irrigated with sewage effluent or when grown on phosphatic clay and muck soils of south Florida. Several companies are considering using leucaena and/or tall grasses for bioenergy in the phosphatic mining area of Polk County, Florida.

  7. Intake, digestibility, nitrogen balance and certain rumen characteristics of Ethiopian Menz sheep fed teff straw supplemented with cotton seed cake, dry sesbania, dry leucaena or fresh leucaena

    Microsoft Academic Search

    M. L. K. Bonsi; P. O. Osuji; A. K. Tuah; N. N. Umunna

    1995-01-01

    Twenty five rumen fistulated Ethiopian Menz sheep were used in a completely randomized block design to determine roughage utilization when different types of supplements (sesbania, leucaena, cotton seed cake (CSC)) and forms (fresh or dry leucaena) were fed. The chemical composition, intake, digestibility, nitrogen balance and rumen degradability coefficients were determined. Rumen pH and ammonia-nitrogen (NH3-N) levels were estimated in

  8. Biomass resource potential for selected crops in Hawaii. [Koa haole (giant leucaena); napier and guinea grass

    SciTech Connect

    Seki, A.

    1982-06-01

    The biomass crops selected for review were koa haole (giant leucaena), napier and guinea grass, and eucalyptus (saligna, grandis, and globulus). The islands examined were Hawaii, Kauai, Maui, and Molokai. The potential land acreage for growing these crops was estimated grossly. As anticipated, the island of Hawaii had the largest land potential with eucalyptus having the greatest potential land acreage.

  9. Isolation of Insertion Sequence ISRLdTAL1145-1 from a Rhizobium sp. (Leucaena diversifolia) and Distribution of Homologous Sequences Identifying Cross-Inoculation Group Relationships †

    PubMed Central

    Rice, Douglas J.; Somasegaran, Padma; MacGlashan, Kathryn; Bohlool, B. Ben

    1994-01-01

    Insertion sequence (IS) element ISRLdTAL1145-1 from Rhizobium sp. (Leucaena diversifolia) strain TAL 1145 was entrapped in the sacB gene of the positive selection vector pUCD800 by insertional inactivation. A hybridization probe prepared from the whole 2.5-kb element was used to determine the distribution of homologous sequences in a diverse collection of 135 Rhizobium and Bradyrhizobium strains. The IS probe hybridized strongly to Southern blots of genomic DNAs from 10 rhizobial strains that nodulate both Phaseolus vulgaris (beans) and Leucaena leucocephala (leguminous trees), 1 Rhizobium sp. that nodulates Leucaena spp., 9 R. meliloti (alfalfa) strains, 4 Rhizobium spp. that nodulate Sophora chrysophylla (leguminous trees), and 1 nonnodulating bacterium associated with the nodules of Pithecellobium dulce from the Leucaena cross-inoculation group, producing distinguishing IS patterns for each strain. Hybridization analysis revealed that ISRLdTAL1145-1 was strongly homologous with and closely related to a previously isolated element, ISRm USDA1024-1 from R. meliloti, while restriction enzyme analysis found structural similarities and differences between the two IS homologs. Two internal segments of these IS elements were used to construct hybridization probes of 1.2 kb and 380 bp that delineate a structural similarity and a difference, respectively, of the two IS homologs. The internal segment probes were used to analyze the structures of homologous IS elements in other strains. Five types of structural variation in homolog IS elements were found. The predominate IS structural type naturally occurring in a strain can reasonably identify the strain's cross-inoculation group relationships. Three IS structural types were found in Rhizobium species that nodulate beans and Leucaena species, one of which included the designated type IIB strain of R. tropici (CIAT 899). Weak homology to the whole IS probe, but not with the internal segments, was found with two Bradyrhizobium japonicum strains. The taxonomic and ecological implications of the distribution of ISRLdTAL1145-1 are discussed. Images PMID:16349459

  10. Structural and docking studies of Leucaena leucocephala Cinnamoyl CoA reductase.

    PubMed

    Prasad, Nirmal K; Vindal, Vaibhav; Kumar, Vikash; Kabra, Ashish; Phogat, Navneet; Kumar, Manoj

    2011-03-01

    Lignin, a major constituent of plant call wall, is a phenolic heteropolymer. It plays a major role in the development of plants and their defense mechanism against pathogens. Therefore Lignin biosynthesis is one of the critical metabolic pathways. In lignin biosynthesis, the Cinnamoyl CoA reductase is a key enzyme which catalyzes the first step in the pathway. Cinnamoyl CoA reductase provides the substrates which represent the main transitional molecules of lignin biosynthesis pathway, exhibits a high in vitro kinetic preference for feruloyl CoA. In present study, the three-dimensional model of cinnamoyl CoA reductase was constructed based on the crystal structure of Grape Dihydroflavonol 4-Reductase. Furthermore, the docking studies were performed to understand the substrate interactions to the active site of CCR. It showed that residues ARG51, ASN52, ASP54 and ASN58 were involved in substrate binding. We also suggest that residue ARG51 in CCR is the determinant residue in competitive inhibition of other substrates. This structural and docking information have prospective implications to understand the mechanism of CCR enzymatic reaction with feruloyl CoA, however the approach will be applicable in prediction of substrates and engineering 3D structures of other enzymes as well. PMID:20512516

  11. Mycorrhizae and phosphorus fertilization effects on survival, growth, total biomass and leaf nutrient levels of two-year old Leucaena leucocephala

    E-print Network

    Mbugua, David Kahuria

    1985-01-01

    county, Texas. 14 ~ytst n The vegetation of this area can be described as a amsquite mixed shrubland with well developed herbaceous plants (Gould 1975). Tta t*ry ' d ' t d by seed 'te (proaonls ((la dnloaa Tor . Var. TL du*ca) atd h 'sachs (Acac...

  12. Mycorrhizae and phosphorus fertilization effects on survival, growth, total biomass and leaf nutrient levels of two-year old Leucaena leucocephala 

    E-print Network

    Mbugua, David Kahuria

    1985-01-01

    high P fixation rates. Tinker (1975) has pointed out that both mycorrhizal and non-mycort hizal plants utilize the P from soil solution. This observation has therefore disputed the idea that mycorrhizae fungi can extract soil P sources... the effect of vesicular-arbuscular mycorrhizae (VAM) inoculation and phosphorus (P) fertilizer application rates on growth, survival snd leaf element content. Growth data was collected over two growing seasons, while leaf nutrient content was monitored...

  13. Predicting field performance of five irrigated tree species using seedling quality assessment in Burkina Faso, West Africa

    Microsoft Academic Search

    J. Bayala; M. Dianda; J. Wilson; S. J. Ouédraogo; K. Sanon

    2009-01-01

    Five exotic tree species (Acacia angustissima (Mil.) Kuntze, A. mangium Wild, Gliricidia sepium (Jacq.) Alp., Leucaena hybrid (L×L), and Leucaena leucocephala (Lam.) de Wit) were investigated to determine whether parameters of nursery seedling stock quality could be used to predict\\u000a their field performance in a plantation irrigated with treated waste-water to produce fodder and wood. Plants were grown in\\u000a the

  14. The potential of alley cropping in improvement of cultivation systems in the high rainfall areas of Zambia. III. Effects on soil chemical and physical properties

    Microsoft Academic Search

    A. Dalland; P. I. Våje; R. B. Matthews; B. R. Singh

    1993-01-01

    A detailed study of the soil chemical and physical properties in seven-year-old alley cropping trial containingLeucaena leucocephala andFlemingia congesta in Northern Zambia is described. There was a strong correlation between the maize yield and the total amount of nitrogen applied, both from prunings and fertiliser, suggesting that a major reason for the observed benefit from alley cropping, particularly withLeucaena, was

  15. Impact of tree coppicing on tree-crop competition in parkland and alley farming systems in semiarid Burkina Faso

    Microsoft Academic Search

    Y. Tilander; G. Ouedraogo; F. Yougma

    1995-01-01

    The aim of this study was to evaluate the effects of tree coppicing on tree-crop competition in farmed parkland and in alley farming, both in semiarid Burkina Faso.Azadirachta indica A. Juss (neem) was studied in the parklands, while neem,Albizia lebbeck (L.) Benth. (albizia) andLeucaena leucocephala (Lam.) de Wit (leucaena) were investigated in the alley farming system. The crop was sorghum

  16. Reforestation using Leucaena Luecocephala, Anacardium Occidentale and Tectona Grandis for Paquera, Costa Rica 

    E-print Network

    Moore, Jane F

    1991-01-01

    VERA I isla Nesrttos Jr FN alas ro I oel I 8 Vv ~ C s, Refuela NaolOnal de Fauna SIIVerlre Curu ~ I I C! C I ~ lv I ~ I Reserve Natur ~ 1 Aosofuta de dado Slaneo With few exceptions, the Nicoyian Peninsula is the hottest and driest part...

  17. GLIRICIDIA MACULATA—A REVIEW

    Microsoft Academic Search

    J. LINDSAY FALVEY

    1982-01-01

    Gliricidia maculata (syn G. sepium) is a fast growing, leguminous, medium sized, thornless tree which can substitute for Leucaena leucocephala as a source of fodder, fuelwood and green manure, in hedges and living fences, and as a shade tree in tea, coffee, and cocoa plantations. It grows in lowland areas of the tropics having mean annual temperatures of 22–30°C. and

  18. Phosphorus and liming effects on early growth of selected plant species grown on an ultisol

    Microsoft Academic Search

    B. T. Kang; D. O. Ladipo; O. Ofeimu

    1995-01-01

    A series of pot experiments were conducted to test the effect of phosphorus (P) application and liming on early growth performance of Zea mays, Mucuna pruriens and nine woody species (Albizia ferruginea, Cajanus cajan, Dactyladenia barteri, Dalbergia sissoo, Enterolobium cyclocarpum, Flemingia macrophylla, Gliricidia sepium, Leucaena leucocephala, and Pentacletra macrophylla) on an Ultisol. Low reponse to liming and high response to

  19. Economic analysis of a simulated alley cropping system for semi-arid conditions, using micro computers

    SciTech Connect

    Hoekstra, D.A.

    1983-01-01

    Returns were simulated for the semi-arid areas in Mackakos District, Kenya (bimodal rainfall distribution, 600 mm/yr) comparing the present system (maize and beans intercropped twice a year) with a Leucaena leucocephala hedgerow system. Although some of the assumptions contain a large element of uncertainty, the results were promising enough for the system to be considered further. 4 references.

  20. Spectrally segmented principal component analysis of hyperspectral imagery for mapping invasive plant species

    Microsoft Academic Search

    F. Tsai; K. Yoshino

    2007-01-01

    Principal component analysis (PCA) is one of the most commonly adopted feature reduction techniques in remote sensing image analysis. However, it may overlook subtle but useful information if directly applied to the analysis of hyperspectral data, especially for the discrimination among different vegetation types. In order to accurately map an invasive plant species (horse tamarind, Leucaena leucocephala) in southern Taiwan

  1. Effect of shade on the growth and mineral nutrition of a C4 perennial grass under field conditions

    Microsoft Academic Search

    Pablo Cruz

    1997-01-01

    The effect of shading by a shrub legume on the growth and nutrient uptake of a C4 tropical grass was studied during four regrowth cycles. Regrowth periods were characterised by contrasting soil water availability. Dichanthium aristatum (Poir.) C. E. Hubbard swards were grown in full sun and under Gliricidia sepium (Jacq.) Walp. and Leucaena leucocephala (Lam.) de Wit with a

  2. Salt tolerances of some mainland tree species select as through nursery screening.

    PubMed

    Miah, Md Abdul Quddus

    2013-09-15

    A study of salt tolerance was carried out on germination, survival and height growth performance of important mesophytic species such as Acacia auriculiformis, Acacia hybrid, Artocarpus heterophyllus, Albizia procera, Albizia lebbeck, Acacia nilotica, Achras sapota, Casuarina equisetifolaia, Emblica officinalis, Leucaena leucocephala, Samania saman, Swetenia macrophylla, Terminalia arjuna, Tamarindus indica, Terminalia bellirica and Thespesia populnea in nursery stage using fresh water and salt (NaCl) solutions of 10, 15 and 20 ppm. Effect of salt on germination, survival performance and height growth performance were examined in this condition. Based on the observation, salt tolerance of these species has been determined Acacia auriculiformis, Acacia hybrid, Achras sapota, Casuarina equisetifolia, Leucaena leucocephala and Tamarindus indica has showed the best capacity to perform in different salinity conditions. Acacia nilotica, Emblica officinalis, Thespesia populnea has performed better. Albizia procera, Samania saman and Terminalia bellirica, germination and height performance showed good but when salinity increases survivability were decreases. PMID:24502152

  3. Nitrogen fixation by trees in relation to soil nitrogen economy

    Microsoft Academic Search

    Y. R. Dommergues

    1995-01-01

    The N2-fixing potential (NFP) (i.e. the amount of fixed N2 in a constraint-free environment) of N2-fixing trees (NFTs) varies with the genotype. The NFP can be higher than 30-50 g N2 fixed tree-1 year-1 in the most active species, be they leguminous trees such asAlbizia lebbeck, Gliricidia sepium andLeucaena leucocephala, or actinorhizal trees such asCasuarina equisetifolia. The actual amount of

  4. Nutrient composition and in vitro ruminal fermentation of tropical legume mixtures with contrasting tannin contents

    Microsoft Academic Search

    C. D. Stürm; T. T. Tiemann; C. E. Lascano; M. Kreuzer; H. D. Hess

    2007-01-01

    Various combinations of a low-tannin herbaceous legume (Vigna unguiculata) and foliage of tanniniferous shrub legumes (Calliandra calothyrsus, Flemingia macrophylla and Leucaena leucocephala) or a low-tannin shrub legume (Cratylia argentea), all mixed together with a low-quality tropical grass (Brachiaria humidicola), were tested in vitro for differences in the effects on ruminal fermentation. Two experiments with the gas transducer technique were carried

  5. Effect of replacement of concentrate mixture with isonitrogenous leaf meal mixture on growth, nutrient utilization and rumen fermentation in goats

    Microsoft Academic Search

    Ajit Pal; R. K. Sharma; Ravindra Kumar; K. Barman

    2010-01-01

    This study was conducted to examine the effect of replacing concentrate mixture with leaf meal mixture of Leucaena leucocephala–Melia azedarach–Morus alba in equal proportion on growth, nutrient utilization, blood and rumen metabolites in growing goats using completely randomized design. Twelve male non-descript goats were divided into two groups, control and experimental, consisting of six animals in each group. The control

  6. Assessment of fodder quality of leaves of multipurpose trees in subtropical humid climate of India

    Microsoft Academic Search

    Chander Datt; M. Datta; N. P. Singh

    2008-01-01

    The leaves of 12 species (Acacia auriculiformis, Albizzia procera, Dalbergia sissoo, Gliricidia maculata, Leucaena leucocephala, Samanea saman, Azadirachta\\u000a indica, Eucalyptus hybrida, Gmelina arborea, Michelia champaca, Morus alba, and Tectona grandis) of Multipurpose trees and shrubs (MPTs) grown in the agroforestry arboretum were evaluated for their nutritional characteristics\\u000a in terms of proximate composition, cell wall constituents, total tannins, major (Ca and

  7. Alchornea cordifolia , a promising indigenous browse species adapted to acid soils in southeastern Nigeria for integrated crop-livestock agroforestry production systems

    Microsoft Academic Search

    A. Larbi; M. A. Jabbar; E. J. Orok; N. B. Idiong; J. Cobbina

    1993-01-01

    Dry matter (DM) production, crude protein, phosphorus fibre contents and goat preference for eight indigenous browse species,Alchornea cordifolia, Diallum guineense, Ficus capensis, Baphia nitida, Manniophytum fulvum, Homalium aylmeri, Glyphaea brevis andRauwolfia vomitoria, and for two exotics,Leucaena leucocephala andGliricidia sepium, in cultivated plots were compared on acid soil in southeastern Nigeria. Total DM production was higher (PAlchornea cordifolia than for the

  8. Beneficial effect of aluminum on growth of plants adapted to low pH soils

    Microsoft Academic Search

    Mitsuru Osaki; Toshihiro Watanabe; Toshiaki Tadano

    1997-01-01

    Plants in which growth was reduced by low and high Al applications were designated as Al-sensitive plant (Hordeum vulgare) and Al-medium tolerant plants (Leucaena leucocephala, Ischaemum barbatum, Stylosanthes guianensis, and Fagopyrum esculentum), respectively, while plants in which growth was not affected or was stimulated by Al application were designated as Al-tolerant plant (Brachiaria ruziziensis) and Al-stimulated plants (Melastoma malabathricum, Melaleuca

  9. Alley cropping on an Ultisol in subhumid Benin. Part 2: Changes in crop physiology and tree crop competition

    Microsoft Academic Search

    D. E. Leihner; R. Ernst-Schaeben; T. P. Akondé; N. Steinmüller

    1996-01-01

    From 1986–92 alley cropping with Leucaena leucocephala (Lam.) de Wit and Cajanus cajan (L.) Millsp. was compared to a no-tree control, and fertilisation with 90, 39 and 75 kg ha–1 N, P and K vs. no fertilisation were studied in maize and cassava grown intercropped or in rotation. Light transmission measurements and row position effects on food crop yield did

  10. Biomass yield and energy value of some fast-growing multipurpose trees in Nigeria

    Microsoft Academic Search

    Joseph A. Fuwape; Shadrach O. Akindele

    1997-01-01

    The above-ground biomass yield of seven-year-old trees of Gliricidia sepium, Gmelina arborea and Leucaena leucocephala grown for fuel production were assessed. The combustion properties of the fuelwood and charcoal produced from the trees (moisture content, density, percentage fixed carbon, volatile matter, micro-elemental composition and heat of combustion) were determined. There were significant differences in the above-ground biomass and the charcoal

  11. Monosaccharides promote flowering in Kniphofia leucocephala in vitro

    Microsoft Academic Search

    Nicolette J. Taylor; Marnie E. Light; Johannes Van Staden

    2007-01-01

    An investigation into the role of carbohydrates in flowering of the endangered species Kniphofia leucocephala Baijnath. (Asphodelaceae) in vitro revealed that a carbohydrate source is essential for the induction of inflorescences.\\u000a Both the concentration and type of sugar influenced the percentage of flowering, with 60 g l?1 fructose and 10 ?M N6-benzyladenine (BA) inducing the best flowering response. A high percentage of flowering

  12. Rhizobium freirei sp. nov., a symbiont of Phaseolus vulgaris that is very effective at fixing nitrogen.

    PubMed

    Dall'Agnol, Rebeca Fuzinatto; Ribeiro, Renan Augusto; Ormeño-Orrillo, Ernesto; Rogel, Marco Antonio; Delamuta, Jakeline Renata Marçon; Andrade, Diva Souza; Martínez-Romero, Esperanza; Hungria, Mariangela

    2013-11-01

    Common bean (Phaseolus vulgaris L.) can establish symbiotic associations with several Rhizobium species; however, the effectiveness of most strains at fixing nitrogen under field conditions is very low. PRF 81(T) is a very effective strain, usually referred to as Rhizobium tropici and used successfully in thousands of doses of commercial inoculants for the common bean crop in Brazil; it has shown high rates of nitrogen fixation in all areas representative of the crop in the country. Here, we present results that indicate that PRF 81(T), although it belongs to the 'R. tropici group', which includes 10 Rhizobium species, R. tropici, R. leucaenae, R. lusitanum, R. multihospitium, R. miluonense, R. hainanense, R. calliandrae, R. mayense, R. jaguaris and R. rhizogenes, represents a novel species. Several morpho-physiological traits differentiated PRF 81(T) from related species. Differences were also confirmed in the analysis of rep-PCR (sharing less than 45?% similarity with the other species), MLSA with recA, atpD and rpoB genes, and DNA-DNA hybridization. The novel species, for which we propose the name Rhizobium freirei sp. nov., is able to establish effective root nodule symbioses with Phaseolus vulgaris, Leucaena leucocephala, Leucaena esculenta, Crotalaria juncea and Macroptilium atropurpureum. The type strain is PRF 81(T) (?=?CNPSo 122(T)?=?SEMIA 4080(T)?=?IPR-Pv81(T)?=?WDCM 440(T)). PMID:23771622

  13. Combining napier grass with leguminous shrubs in contour hedgerows controls soil erosion without competing with crops

    Microsoft Academic Search

    James K. Mutegi; Daniel N. Mugendi; Louis V. Verchot; James B. Kung’u

    2008-01-01

    We established hedges\\/barriers of calliandra (Calliandra calothyrsus Meissner), leucaena (Leucaena trichandra (Zucc.) Urban)) and napier grass (Pennisetum purpureum Schumach) and combination hedges of either calliandra or leucaena with napier grass on slopes exceeding 5% to study the effect\\u000a of vegetative barriers on productivity of arable steep-lands in central Kenya. Hedges\\/barriers were pruned regularly and biomass\\u000a incorporated into the plots. Hedge

  14. Seed and seedling persistence of two leguminous shrubs on a semi-arid site in southwest Texas

    E-print Network

    Wallace, Robert Brittingham

    1991-01-01

    ) moisture regimes. Buried Acacia had maximum survival (& 36%) at 6 weeks and no survival for longer periods, while Leucaena seed survival was 97 (6 weeks) to 71% (1 year). Survival on the soil surface was 72% over 42-d (Acacia) and 94% over 60-d (Leucaena... 55 60 75 V CONCLUSIONS, RESEARCH RECOMMENDATIONS, AND MANAGEMENT IMPLICATIONS REFERENCES 85 90 TABLE OF CONTENTS Continued APPENDICES Page 96 119 vnl LIST OF FIGURES Figure Page 2. 1 Viability of Acacia and Leucaena seeds after 6...

  15. The potential influence of plant-based feed supplements on sperm quantity and quality in livestock: a review.

    PubMed

    Clément, C; Witschi, U; Kreuzer, M

    2012-05-01

    The reproductive performance of male livestock is of economic importance, and improving semen quantity and quality, especially for artificial insemination, additionally helps to avoid the loss of valuable genotypes. The review focuses on the impact of oxidative stress on sperm production and quality in livestock, and the potential role of plant based anti-oxidants to control this impact. From scientific reports dealing with livestock, the paper compiles evidence on effective dietary measures affecting sperm production and quality. Where little or no data are available on livestock, it refers to sources regarding other mammals, including man. The review concentrates on the use of distinct plants as feed supplements rather than on ways to treat deficiencies and imbalances in energy or macro- and micronutrients. Feeding of maca (Lepidium meyenii) and khat (Catha edulis) has been shown to positively affect sperm production and quality in animals. Some evidence points to favourable effects of leucaena (Leucaena leucocephala and Leucaena pallida), sesbania (Sesbania sesban), pomegranate (Punica granatum), tomato (Solanum lycopersicum) and amaranth (Amaranthus hypochondriacus) as well, but studies are either superficial or results are partially contradictory. Finally, the review considers the potential usefulness of medicinal herbs. The list of such plants includes Chinese herbs such as Lycium barbarum, Astralagus membranaceus, Acanthopanacis senticosi, Magnolia officinalis, Cornus officinalis and Psoralea corylifolia and the Indonesian plant Eurycoma longifolia. European candidate plants are Tribulus terrestris and Pendulum murex. Future research should include the screening of other plants, concentrating on the large number of plants rich in metabolites because of their presumed effectiveness. The modes of action often require clarification for the plants with demonstrated effects. PMID:22575847

  16. Grass and herbaceous plants for biomass

    SciTech Connect

    Prine, G.M.; Mislevy, P.

    1983-01-01

    Florida has little fossil fuel resources, but the state does have an adequate climate for high plant biomass production. Grasses and herbaceous plants are renewable resources which could furnish a portion of Florida's energy needs. Dry matter yields of various annual and perennial grasses and herbaceous plants which can be grown in Florida are presented in this paper. Residues of crops already being grown for other reasons would be an economical source of biomass. The best alternative for an energy crop appears to be tropical perennial shrub-like legumes and tall, strong-stemmed grasses that have their top growth killed by frosts each winter and that regrow annually from below-ground regenerative plant parts. Napiergrass or elephantgrass (Pennisetum purpureum L.), leucaena (Leucaena leucocephala (Lam.) de Wit) and sugarcane (Saccharum spp.) are examples of such energy plants. Napiergrass (PI 300086) had dry matter yields when cut once at the end of the season of 44.5 and 52.4 Mg/ha in 1981 and 1982 respectively, at Gainesville, Fla. and 56.7 Mg/ha for the first season after planting (1982) at Ona, Fla. A dry matter yield of 73 Mg/ha was obtained from a 10-year-old clump of leucaena at Gainesville in 1981. However, research needs to be conducted on methods of harvesting and storing biomass plants to be used for energy. Napiergrass and other grasses may be solar dried standing after a freeze or following cutting in the fall and then be rolled into large bales for storage in the open or crude shelters. A year-round supply of economical biomass must be available before grasses and herbaceous plants are widely grown and used for energy purposes. 6 references.

  17. Equilibrium and kinetic studies on biosorption of 2,4,6-trichlorophenol from aqueous solutions by Acacia leucocephala bark.

    PubMed

    Kumar, Nadavala Siva; Woo, Heung-Sik; Min, Kim

    2012-06-01

    Biosorption of 2,4,6-trichlorophenol (2,4,6-TCP) from aqueous solution by biomass prepared from Acacia leucocephala bark, an agricultural solid waste has been investigated in the present study. All the experiments are carried out by batch mode technique. The resulting biosorbent was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The effect of experimental parameters such as contact time, effect of pH (2-10), initial concentration of adsorbate (50-200 mg L(-1)) and amount of biosorbent dosage was evaluated. The removal was found to be pH dependent, and maximum removal was found to be at pH 5.0. The equilibrium time was found to be 3h. The biosorbent dose was increased, and the percentage removal of 2,4,6-TCP was increased, while the adsorption capacity at equilibrium q(e) (mg g(-1)) (amount of 2,4,6-TCP loaded per unit weight of adsorbent) decreased. Biosorption kinetic and isotherm studies showed the pseudo-second-order kinetics with a good correlation coefficient (R(2)=0.999), and both Langmuir and Freundlich isotherms were the best choices to describe the adsorption behaviors. The maximum monolayer biosorption capacity of A. leucocephala bark for 2,4,6-TCP was found to be 256.4 mg g(-1), at 30±1°C according to Langmuir model. This study demonstrated for the first time that the A. leucocephala bark could be an alternative for more costly adsorbents used for removal of 2,4,6-TCP from aqueous media. PMID:22365378

  18. Lactational performance of Jersey cows given Napier fodder (Pennisetum purpureum) with and without protein concentrates in the semi-humid tropics.

    PubMed

    Muinga, R W; Thorpe, W; Topps, J H

    1993-05-01

    Two experiments with 12 and 18 lactating Jersey cows respectively were carried out in the coastal semi-humid zone of Kenya to assess the performance arising from the feeding of chopped Napier fodder (Pennisetum purpureum) given ad libitum with and without one of three sources of protein; fishmeal, copra cake and freshly cut Leucaena (Leucaena leucocephala). Each source supplied approximately 300 g crude protein daily. Dry matter intakes of Napier fodder fed alone averaged 7.1 and 5.5 kg in Experiments 1 and 2 respectively. Additional protein did not affect Napier fodder intake, but total intakes of dry matter were higher for the cows receiving the protein supplements, differences which were significant (P < 0.05) in Experiment 2. Average daily milk production from cows fed Napier fodder alone was 6.4 and 4.2 kg in Experiments 1 and 2 respectively. The additional 300 g crude protein increased milk production by 1.0 to 1.6 kg/day, increases which, except that for fishmeal, were significant (P < 0.05). Weight losses of the cows were either reduced or changed to weight gains by the provision of protein. The results are assessed in relation to the energy and protein requirements for milk production. PMID:8236479

  19. [Effects of different planting modes on the soil permeability of sloping farmlands in purple soil area].

    PubMed

    Li, Jian-Xing; He, Bing-Hui; Mei, Xue-Mei; Liang, Yan-Ling; Xiong, Jian

    2013-03-01

    Taking bare land as the control, this paper studied the effects of different planting modes on the soil permeability of sloping farmlands in purple soil area. For the test six planting modes, the soil permeability was in the order of Eriobotrya japonica > Citrus limon > Vetiveria zizanioides hedgerows +corn >Leucaena leucocephala hedgerows + corn> Hemerocallis fulva > corn> bare land, and decreased with increasing depth. The eigenvalues of soil infiltration were in the order of initial infiltration rate> average infiltration rate> stable infiltration rate. The soil permeability had significant positive linear correlations with soil total porosity, non-capillary porosity, initial moisture content, water holding capacity, and organic matter content, and significant negative linear correlation with soil bulk density. The common empirical infiltration model could well fit the soil moisture infiltration processes under the six planting modes, while the Kostiakov equation could not. PMID:23755487

  20. Macaria mirthae Vargas et al (Lepidoptera: Geometridae): Confirmation of the Use of an Invasive Host Plant in the Northern Atacama Desert of Chile Based on DNA Barcodes.

    PubMed

    Rivera-Cabello, D; Huanca-Mamani, W; Vargas, H A

    2015-08-01

    Macaria mirthae Vargas et al (Lepidoptera: Geometridae) is a geometrid moth native to the northern Atacama Desert of Chile. Its oligophagous larvae are associated with native hosts of the plant family Fabaceae, the most important of which is Acacia macracantha. The invasive tree Leucaena leucocephala (Fabaceae) was recently recorded as a host plant for M. mirthae based on morphology. The taxonomic status of larvae collected on A. macracantha and L. leucocephala was assessed using sequences of the DNA barcode fragment of the cytochrome c oxidase subunit I (COI) gene. Genetic divergence between samples from the host plants was found to be 0%-0.8% (Kimura 2-parameter model). Neighbor-joining and maximum likelihood analyses were also performed, including additional barcode sequences of Neotropical geometrid moths from GenBank and BOLD databases. Sequences of the larvae from both host plants clustered in a single clade with high statistical support in both analyses. Based on these results, it is concluded that M. mirthae has effectively expanded its host range and its larvae are currently feeding on the exotic tree L. leucocephala. Additionally, the importance of this new host association in a highly disturbed habitat is briefly discussed in terms of the field biology of this native geometrid moth. PMID:26174961

  1. Voltammetric trace determination of mercury using plant refuse modified carbon paste electrodes.

    PubMed

    Devnani, Harsha; Satsangee, Soami Piara

    2013-11-01

    Citrus limon peel (kitchen waste) and Leucaena leucocephala seeds (agricultural waste) were used as a modifier for fabrication of modified carbon paste electrode for determination of mercury in aqueous sample using differential pulse anodic stripping voltammetry. Mercury was adsorbed on electrode surface at open circuit and anodic stripping voltammetric scan was run from -0.5 to 0.5 V. Various electrochemical parameters including amount of modifier, supporting electrolyte, accumulating solvent, pH of the accumulating solvent, and accumulation time were investigated. The effect of presence of other metal ions and surfactants was also studied. In comparison C. limon peel proved to be a better modifier than L. leucocephala seed biomass. This was justified by electrode characterization using cyclic voltammetry that indicated decrease in resistance of electrode when C. limon peel was used as modifier and increase when modifier was L. leucocephala seeds. Maximum current response was obtained using 5% C. limon peel biomass, hydrochloric acid as supporting electrolyte, acetate buffer of pH 6 as an accumulating solvent, 10-min accumulation time, and scan rate of 50 mV/s. Linear calibration curves were obtained in the concentration range 100 to 1,000 ?g L(-1) of mercury for accumulation time of 10 min with limit of detection of 57.75 ?g L(-1) and limit of quantification of 192.48 ?g L(-1). This technique does not use mercury as electrode material and, therefore, has a positive environmental benefit. PMID:23709264

  2. Effect of six tropical tanniferous plant extracts on larval exsheathment of Haemonchus contortus.

    PubMed

    Oliveira, Lorena Mayana Beserra de; Bevilaqua, Claudia Maria Leal; Macedo, Iara Tersia Freitas; Morais, Selene Maia de; Monteiro, Maria Vivina Barros; Campello, Claudio Cabral; Ribeiro, Wesley Lyeverton Correia; Batista, Emanuelle Karine Frota

    2011-01-01

    Tanniferous plants represent a promising alternative for controlling gastrointestinal nematodes of small ruminants. This experiment evaluated the effects of extracts from the leaf and stem of Anadenanthera colubrina, Leucaena leucocephala and Mimosa tenuiflora on larval exsheathment of Haemonchus contortus in vitro and verified the role of tannins in this process. Third-stage larvae of H. contortus were incubated with extracts for 3 hours and were exposed to sodium hypochlorite solution. The extracts were tested at 300 ?g.mL(-1) and accompanied by controls: phosphate buffer solution (PBS) and polyvinyl polypyrrolidone (PVPP). The larval exsheathment was evaluated for 60 minutes, and the results were subjected to the Kruskal-Wallis test (p < 0.05). The six extracts blocked larval exsheathment. After PVPP addition, a tannin inhibitor, the exsheathment percentage was similar to the PBS (p > 0.05), except for L. leucocephala and M. tenuiflora leaf extracts. However, pre-incubation with PVPP of these two extracts significantly changed larval exsheathment when compared to the non-treated extracts (p < 0.05). These results suggest that A. colubrina, L. leucocephala and M. tenuiflora could be useful in gastrointestinal nematode control and that tannins are probably the main compounds involved in the observed effects. However, in vivo and toxicological studies should be conducted. PMID:21722491

  3. Effects of tropical high tannin non legume and low tannin legume browse mixtures on fermentation parameters and methanogenesis using gas production technique.

    PubMed

    Seresinhe, T; Madushika, S A C; Seresinhe, Y; Lal, P K; Orskov, E R

    2012-10-01

    In vitro experiments were conducted to evaluate the suitability of several mixtures of high tanniniferous non legumes with low tanniniferous legumes on in vitro gas production (IVGP), dry matter degradation, Ammonia-N, methane production and microbial population. Eight treatments were examined in a randomized complete block design using four non-legumes and two legumes (Carallia integerrima×Leucaena leucocephala (LL) (Trt 1), C. integerrima×Gliricidia sepium (GS) (Trt 2), Aporosa lindeliyana×LL (Trt 3), A. lindeliyana×GS (Trt 4), Ceiba perntandra×LL (Trt 5), C. perntandra×GS (Trt 6), Artocarpus heterophyllus×LL (Trt 7), A. heterophyllus×GS (Trt 8). The condensed tannin (CT) content of non legumes ranged from 6.2% (Carallia integerrima) to 4.9% (Ceiba perntandra) while the CT of legumes were 1.58% (Leucaena leucocephala) and 0.78% (Gliricidia sepium). Forage mixtures contained more than 14% of crude protein (CP) while the CT content ranged from 2.8% to 4.0% respectively. Differences (p<0.05) were observed in in vitro gas production (IGVP) within treatments over a 48 h period dominated by C. perntandra×G. sepium (Trt 6). The net gas production (p<0.05) was also high with Trt6 followed by A. heterophyllus×L. leucocephala (Trt 7) and A. heterophyllus×G. sepium (Trt 8). Highest (p>0.05) NH3-N (ml/200 mg DM) production was observed with the A. heterophyllus×G. sepium (Trt 8) mixture which may be attributed with it's highest CP content. The correlation between IVGP and CT was 0.675 while IVGP and CP was 0.610. In vitro dry matter degradation (IVDMD) was highest in Trt 8 as well. Methane production ranged from 2.57 to 4.79 (ml/200 mg DM) to be synonimous with IVGP. A higher bacteria population (p<0.05) was found in C. perntandra×G. sepium (Trt 6) followed by Artocarpus heterophyllus+G. sepium (Trt 8) and the same trend was observed with the protozoa population as well. The results show that supplementing high tannin non leguminous forages by incremental substitution of legume forage increased gas production parameters, NH3-N, IVDMD and microbial population in the fermentation liquid. Methane production was not significantly affected by the presence of CT or different levels of CP in forage mixtures. Among non legumes, Ceiba perntandra and Artocarpus heterophyllus performed better in mixture with L. leucocephala and G. sepium. PMID:25049496

  4. Comparing the sensitivity of two in vitro assays to evaluate the anthelmintic activity of tropical tannin rich plant extracts against Haemonchus contortus.

    PubMed

    Alonso-Díaz, M A; Torres-Acosta, J F J; Sandoval-Castro, C A; Hoste, H

    2011-09-27

    The present trial aimed at comparing the sensitivity of two in vitro methods, i.e. the larval migration inhibition assay (LMIA) and the larval exsheathment inhibition assay (LEIA), to evaluate the anthelmintic (AH) properties of tannin-rich plant extracts against Haemonchus contortus infective larvae. The two assays were applied on the same batch of H. contortus infective larvae exposed to water/acetonic extracts obtained from four tropical plants with different tannin contents: Acacia gaumeri, Brosimum alicastrum, Havardia albicans and Leucaena leucocephala. Increasing concentrations (0, 75, 150, 300, 600, 1200 ?g/ml PBS) of lyophilized extracts were used in both in vitro assays. A general lineal model test was used to determine the dose-effect in the LMIA or the difference in the percentage of exsheathed larvae between the respective control and treated groups. The LMIA showed a dose-dependent AH effect for H. albicans (P<0.001) and A. gaumeri (P<0.05), but not for L. leucocephala and B. alicastrum. In contrast, the exsheathment process was significantly affected by all doses of H. albicans and A. gaumeri extracts and a significant dose-dependent effect was found for B. alicastrum and L. leucocephala. Calculation of lethal dose (LD) was possible with LEIA using B. alicastrum and L. leucocephala but not with H. albicans and A. gaumeri as the lowest tested concentration was achieving more than 50% inhibition. Calculation of LD with the LMIA results was not feasible. These results suggest that tannin-rich plant extracts are more potent inhibitors of the exsheathment of H. contortus L(3) larvae than their motility. This information underlines the difference of sensitivity between methodological procedures to evaluate the AH properties of plant extracts on the same nematode stage. PMID:21530082

  5. In vitro larval migration and kinetics of exsheathment of Haemonchus contortus larvae exposed to four tropical tanniniferous plant extracts.

    PubMed

    Alonso-Díaz, M A; Torres-Acosta, J F J; Sandoval-Castro, C A; Aguilar-Caballero, A J; Hoste, H

    2008-05-31

    As for some temperate forage, some tropical tanniniferous plants (TTP) from browsing might represent an alternative to chemical anthelmintic. The anthelmintic effect of four TTP (Acacia pennatula, Lysiloma latisiliquum, Piscidia piscipula, Leucaena leucocephala) on Haemonchus contortus was measured using two in vitro assays. First, the effects of increasing concentrations of lyophilized extracts (150, 300, 600, 1200 microg/ml PBS) were tested on H. contortus larvae (L(3)) using the larval migration inhibition (LMI) test. An inhibitor of tannin, polyvinyl polypyrrolidone (PVPP), was used to verify whether tannins were responsible for the AH effect. Secondly, the effects of extracts on larval exsheathment were examined. Larvae (L(3)) were in contact with extracts (1200 microg/ml) for 3h, and then were exposed to an artificial exsheathment procedure with observations of the process at 10 min intervals. A general lineal model (GLM) test was used to determine the dose effect in the LMI test and the difference of the percentage of exsheathed larvae between the control and the treatment groups. A Kruskal Wallis test was used to determine the effect of PVPP on LMI results. The LMI test showed a dose-dependent anthelmintic effect for A. pennatula, L. latisiliquum and L. leucocephala (P<0.01), which disappeared after PVPP addition, confirming the role of tannins. No effect was found for P. piscipula on H. contortus in the LMI test. However, all four plant extracts interfered with the process of L(3) exsheathment which might be involved as a mechanism of action of tannins on H. contortus larvae. A. pennatula, L. latisiliquum and L. leucocephala could be used as an anthelmintic for the control of H. contortus after confirmation based on in vivo studies. PMID:18378085

  6. Preventing establishment: an inventory of introduced plants in Puerto Villamil, Isabela Island, Galapagos.

    PubMed

    Guézou, Anne; Pozo, Paola; Buddenhagen, Christopher

    2007-01-01

    As part of an island-wide project to identify and eradicate potentially invasive plant species before they become established, a program of inventories is being carried out in the urban and agricultural zones of the four inhabited islands in Galapagos. This study reports the results of the inventory from Puerto Villamil, a coastal village representing the urban zone of Isabela Island. We visited all 1193 village properties to record the presence of the introduced plants. In addition, information was collected from half of the properties to determine evidence for potential invasiveness of the plant species. We recorded 261 vascular taxa, 13 of which were new records for Galapagos. Most of the species were intentionally grown (cultivated) (73.3%) and used principally as ornamentals. The most frequent taxa we encountered were Cocos nucifera (coconut tree) (22.1%) as a cultivated plant and Paspalum vaginatum (salt water couch) (13.2%) as a non cultivated plant. In addition 39 taxa were naturalized. On the basis of the invasiveness study, we recommend five species for eradication (Abutilon dianthum, Datura inoxia, Datura metel, Senna alata and Solanum capsicoides), one species for hybridization studies (Opuntia ficus-indica) and three species for control (Furcraea hexapetala, Leucaena leucocephala and Paspalum vaginatum). PMID:17940606

  7. Preventing Establishment: An Inventory of Introduced Plants in Puerto Villamil, Isabela Island, Galapagos

    PubMed Central

    Guézou, Anne; Pozo, Paola; Buddenhagen, Christopher

    2007-01-01

    As part of an island-wide project to identify and eradicate potentially invasive plant species before they become established, a program of inventories is being carried out in the urban and agricultural zones of the four inhabited islands in Galapagos. This study reports the results of the inventory from Puerto Villamil, a coastal village representing the urban zone of Isabela Island. We visited all 1193 village properties to record the presence of the introduced plants. In addition, information was collected from half of the properties to determine evidence for potential invasiveness of the plant species. We recorded 261 vascular taxa, 13 of which were new records for Galapagos. Most of the species were intentionally grown (cultivated) (73.3%) and used principally as ornamentals. The most frequent taxa we encountered were Cocos nucifera (coconut tree) (22.1%) as a cultivated plant and Paspalum vaginatum (salt water couch) (13.2%) as a non cultivated plant. In addition 39 taxa were naturalized. On the basis of the invasiveness study, we recommend five species for eradication (Abutilon dianthum, Datura inoxia, Datura metel, Senna alata and Solanum capsicoides), one species for hybridization studies (Opuntia ficus-indica) and three species for control (Furcraea hexapetala, Leucaena leucocephala and Paspalum vaginatum). PMID:17940606

  8. Phenotypic and biochemical characterization of root nodule bacteria naturally associated with woody tree legumes in Saudi Arabia.

    PubMed

    Alshaharani, Thobayet Safar; Shetta, Nader Desouky

    2015-03-01

    Thirty root-nodulating bacteria isolates were obtained from the roots of Acacia ampliceps (Maslin), A. ehrenbergiana (Hayne.), A. saligna (Labill.), A. seyal (Del.), A. tortilis (Forssk.), A. tortilis subsp. raddiana (Savi.), Leucaena leucocephala (Lam.) and Vicia faba (L.) trees growing in the Riyadh region. The isolates' phenotypic and biochemical properties were characterized by assessing colony appearance, growth rate, resistance to antibiotics and heavy metals, and tolerance to salinity, elevated temperature and pH. All isolates had same colony morphology and grew on yeast extract mannitol and tryptone yeast agar, but not MGS media. The results also revealed considerable diversity among the isolates, which exhibited different patterns of resistance to abiotic stresses. Most isolates tolerated temperatures up to 37 degrees C and could grow from pH 5.5-8.5 and at a high NaCl concentration (2% w/v). The majority of isolates could utilize a variety of carbohydrates. Most of the isolates displayed resistance to antibiotics in the 75 microg ml(-1) range, with approximately 100 pg ml(-1) the maximum concentration at which growth was observed. All isolates were sensitive to aluminum and resistant to other heavy metals tested, and they were able to reduce nitrate and hydrolyze urea. PMID:25895257

  9. Temporal changes of selected chemical properties in three manure - amended soils of Hawaii.

    PubMed

    Ortiz Escobar, M E; Hue, N V

    2008-12-01

    Soil amendment with organic materials (crop residues animal manure, and green manure) reportedly has positive effects on soil properties, from acidity to plant-nutrient availability. To examine that hypothesis, an incubation study was conducted to assess the changes in some chemical properties of three different tropical soils (Andisol, Ultisol, and Oxisol) amended with chicken manure and green manure (Leucaena leucocephala) at the rate of 10tha(-1). The results showed that organic amendments raised soil pH and EC, regardless of the type of manure used. Manuring lowered the concentrations of Mehlich-3 extractable Ca, P, Mn and Si in all soils and decreased the concentration of Mg in the Ultisol and Oxisol. However, manure amendment led to increases in the concentrations of Mg and K in the Andisol. Organic amendments caused a decrease in KCl extractable Al. Initial soluble C levels were highest in the Oxisol (60micromolg(-1)) and lowest in the Andisol (20micromolg(-1)). The concentration of soluble C decreased exponentially with duration of incubation. Three low molecular weight organic molecules (acetic acid, catechol and oxalic acid) out of the eight tested were found in all manure-amended soils. This study quantified the release of some Al chelating organic acids, the reduction of exchangeable Al, and the changes in major plant-nutrients when organic materials were added to nutrient poor, tropical acid soils. PMID:18550367

  10. Description of nests, eggs, and nestlings of the endangered nightingale reed-warbler on Saipan, Micronesia

    USGS Publications Warehouse

    Mosher, S.M.; Fancy, S.G.

    2002-01-01

    We describe the first verified nests, eggs, and nestlings of the Nightingale Reed-Warbler (Acrocephalus luscinia), an endangered species endemic to the Mariana Islands, Micronesia. Nest composition, nest dimensions, and eggs were studied on the island of Saipan. Nests were located within three habitat types: upland introduced tangantangan (Leucaena leucocephala) forest, a native mangrove (Bruguiera gymnorrhiza) wetland, and a native reed (Phragmites karka) wetland. Nesting substrates included five native and two introduced tree species and one native reed species. Nests were composed primarily of dry vine stems, needle-like branchlets of ironwood (Casuarina equisetifolia), and tangantangan petioles. Nests were compact to bulky in construction and were secured to a forked arrangement of branches or stems. The background color of eggs ranged from white to cream to ivory-buff. Eggs were spotted, speckled, and blotched with gray, brown, black, and rust colored markings. Clutch size was 2-4, with a mode of two. Hatchlings were altricial with closed eyelids and devoid of natal down with dark gray to black skin. Nestlings examined prior to fledging resembled the adult plumage, except for the lack of the yellow supercilium found in adults. The nests and eggs have some characteristics similar to those of other Acrocephaline warblers found throughout Micronesia and Polynesia.

  11. Exopolysaccharide mutants of Rhizobium loti are fully effective on a determinate nodulating host but are ineffective on an indeterminate nodulating host.

    PubMed Central

    Hotter, G S; Scott, D B

    1991-01-01

    By Tn5 mutagenesis of Rhizobium loti PN184 (NZP2037 str-1) and selection for nonfluorescence of colonies on Calcofluor agar, eight independently generated expolysaccharide (EPS) mutants (three smooth and five rough) were isolated. The parent strain, PN184, was found to produce an acidic EPS. This EPS was produced. with reduced O acetylation, by the smooth EPS mutants but not by the rough EPS mutants. Lipopolysaccharide was isolated from all mutants and was identical to that of PN184 as defined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. All mutants were resistant to lysis by R. loti bacteriophage phi 2037/1. Cosmids that complemented the mutations in the rough EPS mutants were isolated from a pLAFR1 gene library of NZP2037 by complementation of the nonfluorescent phenotype. The genes identified were shown to be unlinked and located on the chromosome. All mutants were fully effective when inoculated onto Lotus pedunculatus, a determinate nodulating host, but were ineffective, inducing the formation of very small nodules or tumorlike growths, when inoculated onto Leucaena leucocephala, an indeterminate nodulating host. These results, obtained in an isogenic Rhizobium background, support suggestions that acidic EPS is required for effective nodulation of indeterminate nodulating legumes but is not required for effective nodulation of determinate nodulating legumes. Images PMID:1987168

  12. Ecological Indicators of Native Rhizobia in Tropical Soils †

    PubMed Central

    Woomer, Paul; Singleton, Paul W.; Bohlool, B. Ben

    1988-01-01

    The relationship between environment and abundance of rhizobia was described by determining the populations of root nodule bacteria at 14 diverse sites on the island of Maui. Mean annual rainfall at the sites ranged from 320 to 1,875 mm, elevation from 37 to 1,650 m, and soil pH from 4.6 to 7.9. Four different soil orders were represented in this study: inceptisols, mollisols, ultisols, and an oxisol. The rhizobial populations were determined by plant infection counts of five legumes (Trifolium repens, Medicago sativa, Vicia sativa, Leucaena leucocephala, and Macroptilium atropurpureum). Populations varied from 1.1 to 4.8 log10 cells per g of soil. The most frequently occurring rhizobia were Bradyrhizobium spp., which were present at 13 of 14 sites with a maximum of 4.8 log10 cells per g of soil. Rhizobium trifolii and R. leguminosarum occurred only at higher elevations. The presence of a particular Rhizobium or Bradyrhizobium sp. was correlated with the occurrence of its appropriate host legume. Total rhizobial populations were significantly correlated with mean annual rainfall, legume cover and shoot biomass, soil temperature, soil pH, and phosphorus retention. Regression models are presented which describe the relationship of legume hosts, soil climate, and soil fertility on native rhizobial populations. PMID:16347624

  13. Reclamation of tannery polluted soil through phytoremediation.

    PubMed

    Sakthivel, V; Vivekanandan, M

    2009-04-01

    The huge volume of sludge emanating from the tannery effluent treatment plants poses a serious environmental problem. Phytoremediation is an emerging technology in which the plants are employed to reclamate the contaminated soil strewn with heavy metals (metalloids) and toxic compounds. This work focuses the impact of application of tannery sludge on biochemical properties of 6 months old tree saplings of Azadirachta indica A. Juss. (Neem), Melia azedarach Linn. (Wild Neem) and Leucaena leucocephala (Lam) de Wit (Subabool) raised over the tannery sludge in an attempt to use these plants for phytoremediation. The plants raised over the garden soil served as the control. The porosity and water holding capacity of the tannery sludge were higher. The plant growth supporting elements such as Ca, total N2, NO3 and Mg were higher in the sludge. The plants raised over the sludge were found to be dark green with increased morphometric parameters. Electrophoretic profile revealed amplification of a few polypeptides (100, 105, 49 and 55 KDa). The levels of biomolecules and the CO2 absorption increased in 6 months old plants. There was a significant uptake and transport of chromium in all the three tree species suggesting that these plants could be employed in phytoremediation of soils contaminated with heavy metals. PMID:23572927

  14. Development of feeding systems and strategies of supplementation to enhance rumen fermentation and ruminant production in the tropics

    PubMed Central

    2013-01-01

    The availability of local feed resources in various seasons can contribute as essential sources of carbohydrate and protein which significantly impact rumen fermentation and the subsequent productivity of the ruminant. Recent developments, based on enriching protein in cassava chips, have yielded yeast fermented cassava chip protein (YEFECAP) providing up to 47.5% crude protein (CP), which can be used to replace soybean meal. The use of fodder trees has been developed through the process of pelleting; Leucaena leucocephala leaf pellets (LLP), mulberry leaf pellets (MUP) and mangosteen peel and/or garlic pellets, can be used as good sources of protein to supplement ruminant feeding. Apart from producing volatile fatty acids and microbial proteins, greenhouse gases such as methane are also produced in the rumen. Several methods have been used to reduce rumen methane. However, among many approaches, nutritional manipulation using feed formulation and feeding management, especially the use of plant extracts or plants containing secondary compounds (condensed tannins and saponins) and plant oils, has been reported. This approach could help todecrease rumen protozoa and methanogens and thus mitigate the production of methane. At present, more research concerning this burning issue - the role of livestock in global warming - warrants undertaking further research with regard to economic viability and practical feasibility. PMID:23981662

  15. Distribution and phytoavailability of heavy metal chemical fractions in artificial soil on rock cut slopes alongside railways.

    PubMed

    Chen, Zhaoqiong; Ai, Yingwei; Fang, Chen; Wang, Kexiu; Li, Wei; Liu, Shui; Li, Chunlin; Xiao, Jingyao; Huang, Zhiyu

    2014-05-30

    Artificial soil is often sprayed onto cut slopes alongside railroad tracks to promote revegetation. This study evaluated the heavy metal content and the distribution of heavy metal chemical fractions in the soil, as well as the uptake of heavy metals by plants. The soil at four sites was determined to be considerably contaminated with Cd and Pb. The concentrations of Cd and Pb increased with the length of time the railway had been in use and decreased further away from the railway tracks. Pb primarily existed in reducible form but as residual fractions, whereas Cd was predominantly in exchangeable form. A correlation analysis indicated that pH, organic matter, and total phosphorus levels were important factors affecting the distribution of the heavy metal chemical fractions. The amounts of exchangeable Pb and Cd in the soil were highly correlated with their amounts in the plants sampled, indicating that the exchangeable fraction is a better indication of heavy metal phytoavailability than the total amount of heavy metals in the soil. Bioaccumulation and translocation factors indicated that Indigofera amblyantha had moderate tolerance and bioaccumulation capability for Pb, as did Leucaena leucocephala for Cd. These two plant species can serve as ideal slope remediation plants. PMID:24727018

  16. Heterologous exopolysaccharide production in Rhizobium sp. strain NGR234 and consequences for nodule development.

    PubMed Central

    Gray, J X; Zhan, H J; Levery, S B; Battisti, L; Rolfe, B G; Leigh, J A

    1991-01-01

    Rhizobium sp. strain NGR234 produces large amounts of acidic exopolysaccharide. Mutants that fail to synthesize this exopolysaccharide are also unable to nodulate the host plant Leucaena leucocephala. A hybrid strain of Rhizobium sp. strain NGR234 containing exo genes from Rhizobium meliloti was constructed. The background genetics and nod genes of Rhizobium sp. strain NGR234 are retained, but the cluster of genes involved in exopolysaccharide biosynthesis was deleted. These exo genes were replaced with genes required for the synthesis of succinoglycan exopolysaccharide from R. meliloti. As a result of the genetic manipulation, the ability of these hybrids to synthesize exopolysaccharide was restored, but the structure was that of succinoglycan and not that of Rhizobium sp. strain NGR234. The replacement genes were contained on a cosmid which encoded the entire known R. meliloti exo gene cluster, with the exception of exoB. Cosmids containing smaller portions of this exo gene cluster did not restore exopolysaccharide production. The presence of succinoglycan was indicated by staining with the fluorescent dye Calcofluor, proton nuclear magnetic resonance spectroscopy, and monosaccharide analysis. Although an NGR234 exoY mutant containing the R. meliloti exo genes produced multimers of the succinoglycan repeat unit, as does the wild-type R. meliloti, the deletion mutant of Rhizobium sp. strain NGR234 containing the R. meliloti exo genes produced only the monomer. The deletion mutant therefore appeared to lack a function that affects the multiplicity of succinoglycan produced in the Rhizobium sp. strain NGR234 background. Although these hybrid strains produced succinoglycan, they were still able to induce the development of an organized nodule structure on L. leucocephala. The resulting nodules did not fix nitrogen, but they did contain infection threads and bacteroids within plant cells. This clearly demonstrated that a heterologous acidic exopolysaccharide structure was sufficient to enable nodule development to proceed beyond the developmental barrier imposed on mutants of Rhizobium sp. strain NGR234 that are unable to synthesize any acidic exopolysaccharide. Images PMID:2022612

  17. Rehabilitation of a debris-flow prone mountain stream in southwestern China - Strategies, effects and implications

    NASA Astrophysics Data System (ADS)

    Yu, Guo-an; Huang, He Qing; Wang, Zhaoyin; Brierley, Gary; Zhang, Kang

    2012-01-01

    SummaryRehabilitation of Shengou Creek, a small, steep mountain stream in southwestern China that is prone to debris flows, started more than 30 years ago through an integrated program of engineering applications (check dams and guiding dikes), biological measures (reforestation), and social measures (reducing human disturbance). Small and medium-sized check dams and guiding dikes were constructed on key upper and middle sections of the creek to stabilize hillslopes and channel bed. Meanwhile, Leucaena leucocephala, a drought-tolerant, fast-growing, and highly adaptive plant species, was introduced to promote vegetation recovery in the watershed. The collective community structure of tree, shrub, and herb assemblages in the artificial L. leucocephala forest, which developed after 7 years, enhanced soil structure and drastically reduced soil erosion on hillslopes. Cultivation of steep land was strictly controlled in the basin, and some inhabitants were encouraged to move from upstream areas to downstream towns to reduce disturbance. These integrated measures reduced sediment supply from both hillslopes and upstream channels, preventing sediment-related hazards. The development of natural streambed resistance structures (mainly step-pool systems) and luxuriant riparian vegetation aided channel stability, diversity of stream habitat, and ecological maintenance in the creek. These findings are compared with Jiangjia and Xiaobaini Ravines, two adjacent non-rehabilitated debris-flow streams which have climate and geomorphologic conditions similar to Shengou Creek. Habitat diversity indices, taxa richness, biodiversity, and bio-community indices are much higher in Shengou Creek relative to Jiangjia and Xiaobaini Ravines, attesting to the effectiveness of rehabilitation measures.

  18. Economic development through biomass systems integration in central Florida

    SciTech Connect

    Stricker, J.A.; Rahmani, M.; Hodges, A.W. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1995-11-01

    A biomass to energy system for central Florida was conceptualized with sugarcane as the main feedstock. Additional feedstocks include elephantgrass, leucaena (woody tropical legume), and Eucalyptus. Juice will be pressed from sugarcane and sugars fermented into ethanol with conventional technology. Enough sugarcane will be grown to supply a conventional ethanol plant with juice for a 330 day operating period each yr. Juice will be condensed to 24 degrees Brix for direct conversion during the approximately 100 day harvest season and to 70 degrees Brix for storage and use the remaining 230 days. Residues (mainly lignin), from converting lignocellulosic materials to ethanol, will fuel the plant including evaporators for sugarcane juice. Sugarcane presscake, elephantgrass, leucaena, and Eucalyptus will be feedstocks for the lignocellulose conversion processes. The lignocellulose plant will be sized to convert all sugarcane presscake as it is produced to reduce storage costs. Elephantgrass, leucaena and Eucalyptus will feed the plant outside sugarcane harvest season. The biomass/energy system will produce 123,230,000 L (32,830,000 gal) of ethanol per year with 90% conversion of sugars from juice, hemicellulose, and cellulose to ethanol. Estimated cost of producing ethanol form various feedstocks include: sugarcane $0.25/L ($0.94/gal), elephantgrass $0.30/L ($1.13/gal), 1 leucaena $0.28/L ($1.06/gal), and Eucalyptus $0.28/L (1.07/gal). Future opportunities exist for development of a chemical industry based on lignocellulose materials from biomass.

  19. The differential effects of supplementation with fodder from different tree legumes on feed intake and digestibility of

    E-print Network

    Boyer, Edmond

    and digestibility of nutrients in sheep fed on maize stover E Masama JH Topps NT Ngongoni BV Maasdorp 1 Department protein content and poor digestibility due to high neutral detergent fibre content. Supplementation with affordable forage legumes is expected to improve both intake and digestibility. Fodder from Leucaena

  20. Landscape and microsite influences on shrub recruitment in a disturbed semi-arid Quercus-Juniperus woodland

    Microsoft Academic Search

    M. K. Owens; R. B. Wallace; S. R. Archer

    1995-01-01

    Seedling demography of the leguminous shrubs Leucaena pulverulenta and Acacia berlandieri was monitored to determine the functional role of microsites in the resto- ration of disturbed semiarid woodlands. Seeds were sown on replicated landscapes during 1989 and again in 1990 into four microsites after brush clearing: 1) Rocky, with shallow soils (<10 cm) and low vegetative cover (<<50%), 2) Herbaceous,

  1. Effect of feeding urea treated maize stover on growth and nutrient utilization by sheep and goats

    Microsoft Academic Search

    M. Chandrasekharaiah; M. R. Reddy; G. V. N. Reddy

    1996-01-01

    The average daily gains (ADG) recorded were not different among the three rations. However, Ration 1 containing concentrate supplement had better feed efficiency compared with other rations, though the cost of feed kg?1 gain was more on this ration. Further, subabul leaf meal (Leucaena l.) was superior to sunhemp hay meal (Crotalaria j.) in supporting the growth in lambs and

  2. Nutrient Utilisation in Growing Cambodian Cattle

    E-print Network

    forage types (rice bran, rice straw, para grass, cassava foliage, leucaena leaves, water hyacinth leaves. In an experimental study examining the effects of different levels of dietary supplementation with sun-dried cassava to increase with increasing intake of cassava foliage, but DM and fibre digestibility decreased

  3. Changes in soil quality indicators under long-term sewage irrigation in a sub-tropical environment

    NASA Astrophysics Data System (ADS)

    Masto, Reginald Ebhin; Chhonkar, Pramod K.; Singh, Dhyan; Patra, Ashok K.

    2009-01-01

    Though irrigation with sewage water has potential benefits of meeting the water requirements, the sewage irrigation may mess up to harm the soil health. To assess the potential impacts of long-term sewage irrigation on soil health and to identify sensitive soil indicators, soil samples were collected from crop fields that have been irrigated with sewage water for more than 20 years. An adjacent rain-fed Leucaena leucocephala plantation system was used as a reference to compare the impact of sewage irrigation on soil qualities. Soils were analyzed for different physical, chemical, biological and biochemical parameters. Results have shown that use of sewage for irrigation improved the clay content to 18-22.7%, organic carbon to 0.51-0.86% and fertility status of soils. Build up in total N was up to 2,713 kg ha-1, available N (397 kg ha-1), available P (128 kg ha-1), available K (524 kg ha-1) and available S (65.5 kg ha-1) in the surface (0.15 m) soil. Long-term sewage irrigation has also resulted a significant build-up of DTPA extractable Zn (314%), Cu (102%), Fe (715%), Mn (197.2), Cd (203%), Ni (1358%) and Pb (15.2%) when compared with the adjacent rain-fed reference soil. Soils irrigated with sewage exhibited a significant decrease in microbial biomass carbon (-78.2%), soil respiration (-82.3%), phosphatase activity (-59.12%) and dehydrogenase activity (-59.4%). An attempt was also made to identify the sensitive soil indicators under sewage irrigation, where microbial biomass carbon was singled out as the most sensitive indicator.

  4. A ripening associated peroxidase from papaya having a role in defense and lignification: heterologous expression and in-silico and in-vitro experimental validation.

    PubMed

    Pandey, Veda P; Dwivedi, Upendra N

    2015-01-25

    Fruit ripening associated full length cDNA of a peroxidase from papaya was cloned and heterologously expressed. The expressed peroxidase was activated by in-vitro re-folding in the presence of hemin and calcium. The purified recombinant peroxidase exhibited broad substrate affinity in the order of o-dianisidine>pyrogallol>guaiacol and was found to be a homotetramer of 155kDa with each subunit having a size of 38kDa. The basis of the distinctive preferences for various substrates was investigated through in-silico molecular modeling approaches. Thus, when the modeled papaya peroxidase-heme complex was docked with these substrates, the in-silico binding efficiency was found to be in agreement with those of wet lab results with the involvement of Arg37, Phe40, His41, Pro137, Asn138, His139, His167, and Phe239 as the common interacting residues in all the cases. However, the binding of the different substrates were found to be associated with conformational changes in the peroxidase. Thus, in the case of o-dianisidine (the most efficient substrate), the protein was folded in the most compact fashion when compared to guaiacol (the least efficient substrate). Protein function annotation analyses revealed that the papaya peroxidase may have biological roles in oxidation-reduction processes, stresses, defense responses etc. In order to further validate its role in lignifications, the papaya peroxidase was compared with a lignin biosynthetic peroxidase from Leucaena leucocephala, a tree legume. Thus, based on 3D structure superimposition and docking, both peroxidases exhibited a great extent of similarity suggesting the papaya peroxidase having a role in lignification (defense response) too. The predicted functions of papaya peroxidase in defense response and lignification were further validated experimentally using qRT-PCR analyses and measurement of oxidation of coniferyl alcohol. PMID:25447898

  5. Classification of the uptake hydrogenase-positive (Hup+) bean rhizobia as Rhizobium tropici.

    PubMed Central

    van Berkum, P; Navarro, R B; Vargas, A A

    1994-01-01

    Phenotypic and genetic characterization indicated that Hup+ bean rhizobial strains are type IIA and type IIB Rhizobium tropici. The Hup+ strain USDA 2840, which did not cluster with either of the two types of R. tropici in a restriction fragment length polymorphism analysis, had electrophoretic patterns of PCR products generated with primers for repetitive extragenic palindromic and enterobacterial repetitive intergeneric consensus sequences similar to those of three reference strains of R. tropici type IIA. The Hup+ strain USDA 2738, which clustered with the reference strain of R. tropici IIB in a restriction fragment length polymorphism analysis, had electrophoretic patterns of PCR products generated with primers for repetitive extragenic palindromic and enterobacterial repetitive intergeneric consensus sequences more closely resembling those of the reference strains of R. tropici type IIA than those of type IIB. DNA amplification with the Y1 and Y2 primers to generate a portion of the 16S rDNA operon was useful to distinguish R. tropici type IIA strains from other bean rhizobial strains. The phylogenetic position of the type IIA strain of R. tropici USDA 2840, determined from the partial 16S rDNA sequence, indicated a more distant relationship with the type IIB strain of R. tropici CIAT899 than with the as yet unnamed rhizobial species of Leucaena leucocephala, TAL 1145. Therefore, we suggest that it may be appropriate either to separate R. tropici types IIA and IIB into two different species or to identify TAL 1145 to the species level as a third type of R. tropici. Images PMID:8135515

  6. Characterization of Rhizobium grahamii extrachromosomal replicons and their transfer among rhizobia

    PubMed Central

    2014-01-01

    Background Rhizobium grahamii belongs to a new phylogenetic group of rhizobia together with Rhizobium mesoamericanum and other species. R. grahamii has a broad-host-range that includes Leucaena leucocephala and Phaseolus vulgaris, although it is a poor competitor for P. vulgaris nodulation in the presence of Rhizobium etli or Rhizobium phaseoli strains. This work analyzed the genome sequence and transfer properties of R. grahamii plasmids. Results Genome sequence was obtained from R. grahamii CCGE502 type strain isolated from Dalea leporina in Mexico. The CCGE502 genome comprises one chromosome and two extrachromosomal replicons (ERs), pRgrCCGE502a and pRgrCCGE502b. Additionally, a plasmid integrated in the CCGE502 chromosome was found. The genomic comparison of ERs from this group showed that gene content is more variable than average nucleotide identity (ANI). Well conserved nod and nif genes were found in R. grahamii and R. mesoamericanum with some differences. R. phaseoli Ch24-10 genes expressed in bacterial cells in roots were found to be conserved in pRgrCCGE502b. Regarding conjugative transfer we were unable to transfer the R. grahamii CCGE502 symbiotic plasmid and its megaplasmid to other rhizobial hosts but we could transfer the symbiotic plasmid to Agrobacterium tumefaciens with transfer dependent on homoserine lactones. Conclusion Variable degrees of nucleotide identity and gene content conservation were found among the different R. grahamii CCGE502 replicons in comparison to R. mesoamericanum genomes. The extrachromosomal replicons from R. grahamii were more similar to those found in phylogenetically related Rhizobium species. However, limited similarities of R. grahamii CCGE502 symbiotic plasmid and megaplasmid were observed in other more distant Rhizobium species. The set of conserved genes in R. grahamii comprises some of those that are highly expressed in R. phaseoli on plant roots, suggesting that they play an important role in root colonization. PMID:24397311

  7. Determination of Tropical Forage Preferences Using Two Offering Methods in Rabbits

    PubMed Central

    Safwat, A. M.; Sarmiento-Franco, L.; Santos-Ricalde, R. H.; Nieves, D.

    2014-01-01

    Two methods of feed preference trials were compared to evaluate the acceptability of 5 fresh foliages: Leucaena leucocephala, Moringa oleifera, Portulaca oleracea, Guazuma ulmifolia, and Brosimum alicastrum that was included as control. The evaluation included chemical analyses and forage intake by rabbits. The first method was a cafeteria trial; 12 California growing rabbits aged 8 wk, allocated in individual cages, were offered the five forage plants at the same time inside the cage, while in the second trial 60 California growing rabbits aged 8 wk, allocated individually, were randomly distributed into 5 experimental groups (n = 12/group); for each group just one forage species was offered at a time. The testing period for each method lasted for 7 d, preceded by one week of adaptation. The results showed that B. alicastrum and L. lecocephala were the most preferred forages while on the contrary G. ulmifolia was the least preferred one by rabbits. The results also revealed that the CV% value for the 2nd method (16.32%), which the tested forages were presented separately to rabbits, was lower and methodologically more acceptable than such value for the 1st method (34.28%), which all forages were presented together at the same time. It can be concluded that a range of tropical forages were consumed in acceptable quantities by rabbits, suggesting that diets based on such forages with a concentrate supplement could be used successfully for rabbit production. However, growth performance studies are still needed before recommendations could be made on appropriate ration formulations for commercial use. PMID:25049983

  8. Phenotypic, molecular and symbiotic characterization of the rhizobial symbionts of Desmanthus paspalaceus (Lindm.) Burkart that grow in the province of Santa Fe, Argentina.

    PubMed

    Fornasero, Laura Viviana; Del Papa, María Florencia; López, José Luis; Albicoro, Francisco Javier; Zabala, Juan Marcelo; Toniutti, María Antonieta; Pensiero, José Francisco; Lagares, Antonio

    2014-01-01

    Desmanthus paspalaceus (Lindm.) Burkart belongs to the D. virgatus complex, subfamily Mimosoidae. The known potential as livestock fodder of several of these legumes prompted us to undertake a phenotypic, molecular, and symbiotic characterization of the D. paspalaceus symbionts in the Santa Fe province, Argentina. The rhizobia collected--containing isolates with different abiotic-stress tolerances--showed a remarkable genetic diversity by PCR fingerprinting, with 11 different amplification profiles present among 20 isolates. In selected isolates 16S-rDNA sequencing detected mesorhizobia (60%) and rhizobia (40%) within the collection, in contrast to the genus of the original inoculant strain CB3126--previously isolated from Leucaena leucocephala--that we typified here through its 16S rDNA as Sinorhizobium terangae. The results revealed the establishment by diverse bacterial genera--rhizobia, sinorhizobia, and mesorhizobia--of full N2-fixing symbiotic associations with D. paspalaceus. This diversity was paralleled by the presence of at least two different nodC allelic variants. The identical nodC alleles of the Mesorhizobia sp. 10.L.4.2 and 10.L.5.3 notably failed to group within any of the currently described rhizo-/brady-/azorhizobial nodC clades. Interestingly, the nodC from S. terangae CB3126 clustered close to homologs from common bean nodulating rhizobia, but not with the nodC from S. terangae WSM1721 that nodulates Acacia. No previous data were available on nod-gene phylogeny for Desmanthus symbionts. A field assay indicated that inoculation of D. paspalaceus with the local Rhizobium sp. 10L.11.4 produced higher aerial-plant dry weights compared to S. teranga CB3126-inoculated plants. Neither the mesorhizobia 10.L.4.2 or 10.L.5.3 nor the rhizobium 10L.11.4 induced root nodules in L. leucocephala or P. vulgaris. The results show that some of the local isolates have remarkable tolerances to several abiotic stresses including acidity, salt, and temperature; while exhibiting prominent N2 fixation; thus indicating suitability as candidates for inoculation of D. paspalaceus. PMID:25153989

  9. Potential of tannin-rich plants for modulating ruminal microbes and ruminal fermentation in sheep.

    PubMed

    Rira, M; Morgavi, D P; Archimède, H; Marie-Magdeleine, C; Popova, M; Bousseboua, H; Doreau, M

    2015-01-01

    The objective of this work was to study nutritional strategies for decreasing methane production by ruminants fed tropical diets, combining in vitro and in vivo methods. The in vitro approach was used to evaluate the dose effect of condensed tannins (CT) contained in leaves of Gliricidia sepium, Leucaena leucocephala, and Manihot esculenta (39, 75, and 92 g CT/kg DM, respectively) on methane production and ruminal fermentation characteristics. Tannin-rich plants (TRP) were incubated for 24 h alone or mixed with a natural grassland hay based on Dichanthium spp. (control plant), so that proportions of TRP were 0, 0.25, 0.5, 0.75, and 1.0. Methane production, VFA concentration, and fermented OM decreased with increased proportions of TRP. Numerical differences on methane production and VFA concentration among TRP sources may be due to differences in their CT content, with greater effects for L. leucocephala and M. esculenta than for G. sepium. Independently of TRP, the response to increasing doses of CT was linear for methane production but quadratic for VFA concentration. As a result, at moderate tannin dose, methane decreased more than VFA. The in vivo trial was conducted to investigate the effect of TRP on different ruminal microbial populations. To this end, 8 rumen-cannulated sheep from 2 breeds (Texel and Blackbelly) were used in two 4 × 4 Latin square designs. Diets were fed ad libitum and were composed of the same feeds used for the in vitro trial: control plant alone or combined with pellets made from TRP leaves at 44% of the diet DM. Compared to TRP, concentration of Ruminococcus flavefaciens was greater for the control diet and concentration of Ruminococcus albus was least for the control diet. The methanogen population was greater for Texel than for Blackbelly. By contrast, TRP-containing diets did not affect protozoa or Fibrobacter succinogenes numbers. Hence, TRP showed potential for mitigating methane production by ruminants. These findings suggest that TRP fed as pellets could be used to decrease methane production. PMID:25568379

  10. In vitro screening of plant lectins and tropical plant extracts for anthelmintic properties.

    PubMed

    Ríos-de Álvarez, L; Jackson, F; Greer, A; Bartley, Y; Bartley, D J; Grant, G; Huntley, J F

    2012-05-25

    Lectins are plant secondary metabolites (PSM) found in many forages and which may confer anthelmintic properties to gastrointestinal parasites through disrupting the development of parasitic larvae throughout its life cycle. In experiment 1, the ability of the plant lectins jacalin (JAC), concanavalin A (Con A), phytohemagglutinin E2L2 (PHA-E2L2), phytohemagglutinin L4 (PHA-L4), phytohemagglutinin E3L (PHA-E3L), kidney bean albumin (KBA), Robinia pseudoacacia agglutinin (RPA), Maackia amurensis lectin (MAA), Maclura pomifera agglutinin (MAA), Dolichos biflorus agglutinin (DBA), wheat germ agglutinin (WGA) and Galanthus nivalis agglutinin (GNA) to disrupt the feeding of the first stage larvae (L(1)) of the sheep gastro-intestinal nematodes (GIN) Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus colubriformis was investigated using a larval feeding inhibition test (LFIT). Only PHA-E3L, WGA and Con A had a potent effect on disrupting larval feeding of all of the three species of GIN investigated. The lectin concentration required to inhibit feeding in 50% of L(1) (IC50) was 7.3±1.2, 8.3±1.4 and 4.3±1.7 ?g/ml for PHA-E3L; 59.1±32.4, 58.7±11.9 and 8.1±7.0 ?g/ml for Con A and 78.9±11.2, 69.4±8.1 and 28.0±14.1 ?g/ml for WGA for T. circumcincta, H. contortus and T. colubriformis larvae, respectively (P=0.006). The addition of the lectin inhibitors fetuin, glucose/mannose or N-acetylglucosamine for PHA-E3L, Con A and WGA, respectively, caused an increase in the proportion of larvae that had fed at all concentrations for PHA-E3L only. In experiment 2, the effect of extracts from the tropical plants Azadiractha indica, Trichanthera gigantea, Morus alba, Gliricidia sepium and Leucaena leucocephala on the feeding behaviour of H. contortus L(1,) was examined. A. indica, T. gigantea and M. alba failed to inhibit 50% of larvae from feeding at concentrations up to 10mg plant extract per ml. In contrast, both G. sepium and L. leucocephala demonstrated a dose-dependent effect on larval feeding with respective IC50 estimates (mean±s.e.) of 0.015 mg/ml ±0.001 and 3.465 mg/ml ±0.144, effects which were partly reversed by the inclusion of either the tannin inhibitor polyethylene glycol or the lectin inhibitor Fetuin. These studies demonstrate that plant lectins can have an inhibitory effect on the feeding behaviour of first stage larvae of ovine GIN in vitro. Moreover they also provide novel evidence that lectins may contribute to the anthelmintic properties of some tropical forage plant extracts, such as G. sepium and L. leucocephala. PMID:22130336

  11. Economics of dual purpose production alternatives in the Mexican tropics

    E-print Network

    Ochoa-Ochoa, Rene Federico

    1997-01-01

    purpose production system. Muinga, Thorpe and Topps, as well as Muinga et al. 15 achieved signiffcant advancements in milk production and body weight in crossbred cows by supplementing leucaena forage in a napier grass based diet. Lactation functions... and it relies less on advanced management practices and technology. The system is heavily dependent on grazing of tropical grasses with minimum supplementation using industrial and agricultural by-products. This production system had 21 percent of the total...

  12. Effect of addition of organic residues, farmyard manure and fertilizer nitrogen on soil fertility in rice?wheat cropping system

    Microsoft Academic Search

    Rajendra Prasad; B. N. Misra

    2001-01-01

    A field experiment was conducted for 3 crop years (July?June) at the Indian Agricultural Research Institute, New Delhi to study the effects of Sesbania and cowpea green manuring (GM) and incorporation of mungbean residues after harvesting grain, Leucaena loppings, FYM and wheat straw incorporation before planting rice and application of 0,40,80 and 120 kg N ha to rice on the

  13. Effect of complete feed block on nutrient utilisation and rumen fermentation in Barbari goats

    Microsoft Academic Search

    A. K Samanta; K. K Singh; M. M Das; S. B Maity; S. S Kundu

    2003-01-01

    Fifteen Barbari goats (average BW 13kg) were randomly divided into three groups of five animals each. All animals were fed complete diets consisting of natural grass hay and concentrate mixture in the ratio of 60:40 on the DM basis. In the concentrate mixture, 15% (T2) or 30% (T3) CP of mustard cake was replaced with Leucaena leaf meal (LLM). The

  14. Mimosine Mitigates Oxidative Stress in Selenium Deficient Seedlings of Vigna radiata Part I: Restoration of Mitochondrial Function

    Microsoft Academic Search

    K. Lalitha; S. Rajendra Kulothungan

    2007-01-01

    Mimosine, a non-protein plant amino acid found in Mimosa pudica and certain species of Leucaena, was beneficial for the growth of seedlings of Vigna radiata germinated under selenium-deficient stressed condition (?Se stressed) despite the recognized toxicity of the allelochemical.\\u000a Exposure of mimosine at 0.1 mM (Mim-0.1) promoted the growth of the seedlings and significantly enhanced mitochondrial functional\\u000a efficiency. Growth-related parameters including

  15. Nitrogen Metabolism in Lactating Goats Fed with Diets Containing Different Protein Sources

    PubMed Central

    Santos, A. B.; Pereira, M. L. A.; Silva, H. G. O.; Pedreira, M. S.; Carvalho, G. G. P.; Ribeiro, L. S. O.; Almeida, P. J. P.; Pereira, T. C. J.; Moreira, J. V.

    2014-01-01

    This study aimed to evaluate urea excretion, nitrogen balance and microbial protein synthesis in lactating goats fed with diets containing different protein sources in the concentrate (soybean meal, cottonseed meal, aerial part of cassava hay and leucaena hay). Four Alpine goats whose mean body weight was 42.6±6.1 kg at the beginning of the experiment, a mean lactation period of 94.0±9.0 days and a production of 1.7±0.4 kg of milk were distributed in a 4×4 Latin square with four periods of 15 days. Diets were formulated to be isonitrogenous, containing 103.0 g/kg of CP, 400 g/kg of Tifton 85 hay and 600 g/kg of concentrate. Diet containing cottonseed meal provided (p<0.05) increased excretion of urea and urea nitrogen in the urine (g/d and mg/kg of BW) when compared with leucaena hay. The diets affected the concentrations of urea nitrogen in plasma (p<0.05) and excretion of urea nitrogen in milk, being that soybean meal and cottonseed meal showed (p<0.05) higher than the average aerial part of the cassava hay. The use of diets with cottonseed meal as protein source in the concentrate in feeding of lactating goats provides greater nitrogen excretion in urine and negative nitrogen balance, while the concentrate with leucaena hay as a source of protein, provides greater ruminal microbial protein synthesis. PMID:25050000

  16. Assessment of phytochemical content, polyphenolic composition, antioxidant and antibacterial activities of Leguminosae medicinal plants in Peninsular Malaysia

    PubMed Central

    2011-01-01

    Background Many medicinal plants from Leguminosae family can be found easily in Malaysia. These plants have been used as traditional medicines by local ethnic groups, where they are prepared as decoction, pastes for wound infections, and some have been eaten as salad. This paper focused on the assessment of antioxidant potential, antibacterial activity and classes of phytochemicals of nine plants from the Leguminosae family. Methods Acacia auriculiformis, Bauhinia kockiana, Bauhinia purpurea, Caesalpinia pulcherrima, Calliandra tergemina, Cassia surattensis, Leucaena leucocephala, Peltophorum pterocarpum, and Samanea saman were extracted with aqueous methanol and dichloromethane:methanol mixture to test for antioxidant and antibacterial activities. The Folin-Ciocalteu assay was conducted to quantify the total phenolic content and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to determine the free radical quenching capacity. Antibacterial activity was assessed using disc diffusion (Kirby-Bauer) assay. Screening for major classes of phytochemical was done using standard chemical tests. Results B. kockiana flowers and C. pulcherrima leaves contained high total phenolic content (TPC) and strong DPPH radical scavenging ability with TPC of 8280 ± 498 mg GAE/100 g, IC50 of 27.0 ± 5.0 ?g/mL and TPC of 5030 ± 602 mg GAE/100 g, IC50 of 50.0 ± 5.0 ?g/mL respectively. Positive correlation was observed between TPC and free radical scavenging ability. Most extracts showed antibacterial activity against Gram positive bacteria at 1 mg, while none showed activity against Gram negative bacteria at the same dose. All extracts (except Samanea saman flower) showed antibacterial activity against two strains of methicillin resistant Staphylococcus aureus (MRSA) with MID values ranging between 100 ?g/disc and 500 ?g/disc. Conclusion The potential source of antioxidant and antibacterial agents, especially for MRSA infection treatments were found in B. kockiana, C. pulcherrima, C. tergemina and P. pterocarpum. These preliminary results would be a guide in the selection of potential candidates for further pharmacological study and in search of new drug candidate in treating MRSA infections. PMID:21306653

  17. Charcoal and activated carbon at elevated pressure

    SciTech Connect

    Antal, M.J. Jr.; Dai, Xiangfeng; Norberg, N. [Univ. of Hawaii at Manoa, Honolulu, HI (United States)] [and others

    1995-12-01

    High quality charcoal has been produced with very high yields of 50% to 60% from macadamia nut and kukui nut shells and of 44% to 47% from Eucalyptus and Leucaena wood in a bench scale unit at elevated pressure on a 2 to 3 hour cycle, compared to commercial practice of 25% to 30% yield on a 7 to 12 day operating cycle. Neither air pollution nor tar is produced by the process. The effects of feedstock pretreatments with metal additives on charcoal yield are evaluated in this paper. Also, the influences of steam and air partial pressure and total pressure on yields of activated carbon from high yield charcoal are presented.

  18. Distribution, density, and biomass of introduced small mammals in the southern mariana islands

    USGS Publications Warehouse

    Wiewel, A.S.; Adams, A.A.Y.; Rodda, G.H.

    2009-01-01

    Although it is generally accepted that introduced small mammals have detrimental effects on island ecology, our understanding of these effects is frequently limited by incomplete knowledge of small mammal distribution, density, and biomass. Such information is especially critical in the Mariana Islands, where small mammal density is inversely related to effectiveness of Brown Tree Snake (Boiga irregularis) control tools, such as mouse-attractant traps. We used mark-recapture sampling to determine introduced small mammal distribution, density, and biomass in the major habitats of Guam, Rota, Saipan, and Tinian, including grassland, Leucaena forest, and native limestone forest. Of the five species captured, Rattus diardii (sensu Robins et al. 2007) was most common across habitats and islands. In contrast, Mus musculus was rarely captured at forested sites, Suncus murinus was not captured on Rota, and R. exulans and R. norvegicus captures were uncommon. Modeling indicated that neophobia, island, sex, reproductive status, and rain amount influenced R. diardii capture probability, whereas time, island, and capture heterogeneity influenced S. murinus and M. musculus capture probability. Density and biomass were much greater on Rota, Saipan, and Tinian than on Guam, most likely a result of Brown Tree Snake predation pressure on the latter island. Rattus diardii and M. musculus density and biomass were greatest in grassland, whereas S. murinus density and biomass were greatest in Leucaena forest. The high densities documented during this research suggest that introduced small mammals (especially R. diardii) are impacting abundance and diversity of the native fauna and flora of the Mariana Islands. Further, Brown Tree Snake control and management tools that rely on mouse attractants will be less effective on Rota, Saipan, and Tinian than on Guam. If the Brown Tree Snake becomes established on these islands, high-density introduced small mammal populations will likely facilitate and support a high-density Brown Tree Snake population, even as native species are reduced or extirpated. ?? 2009 by University of Hawai'i Press All rights reserved.

  19. Genetic diversity of Rhizobium from nodulating beans grown in a variety of Mediterranean climate soils of Chile.

    PubMed

    Baginsky, Cecilia; Brito, Belén; Scherson, Rosita; Pertuzé, Ricardo; Seguel, Oscar; Cañete, Alejandro; Araneda, Cristian; Johnson, Warren E

    2015-04-01

    In spite of potentially being an important source of rhizobial diversity and a key determinant of common bean productivity, there is a paucity of data on Rhizobium genetic variation and species composition in the important bean producing area of Chile and only one species has been documented (Rhizobium leguminosarum). In this study, 240 Rhizobium isolates from Torcaza bean (Phaseolus vulgaris L.) nodules established in the highest bean producing area in Chile (33°34'S-70°38'W and 37°36'S-71°47'W) were characterized by PCR-RFLP markers for nodC gene, revealing eight banding patterns with the polymorphic enzyme Hinf I. The locality of San Agustín de Aurora in Central Chile (35°32'S-71°29'W) had the highest level of diversity. Isolates were classified by species using PCR-RFLP markers for 16S rDNA gene and were confirmed by sequencing an internal fragment of the 16S rDNA gene. The results confirmed the presence of R. leguminosarum and three other species of rhizobia nodulating beans in South Central Chile (R. etli, R. tropici and R. leucaenae). R. tropici and R. leucaenae showed the least genetic variation and were most commonly identified in acid soils, while R. etli was the most common species in slightly acidic to moderately alkaline soils, with higher levels of organic matter content. R. leguminosarum was identified in almost all soils, was the most genetically diverse, and was the most common, being documented in soils with pH that ranged between 5.3 and 8.2, and with organic matter content between 2.1 and 4 %. PMID:25533847

  20. Population structure and loss of genetic diversity in the endangered white-headed duck, Oxyura leucocephala

    E-print Network

    Sorenson, Michael

    Population structure and loss of genetic diversity in the endangered white-headed duck, Oxyura Key words: bottleneck, mtDNA, museum specimens, Oxyura, phylogeography, white-headed duck, waterfowl Abstract The white-headed duck is a globally threatened species native to the Palaearctic with a range

  1. Microsatellite markers for two stifftail ducks: the white-headed duck, Oxyura leucocephala, and the ruddy duck, O. jamaicensis

    Microsoft Academic Search

    VIOLETA MUÑOZ-FUENTES; NICLAS GYLLENSTRAND; JUAN J. NEGRO; ANDY J. GREEN; CARLES VILÀ

    Hybridization with a close relative, the North American ruddy duck (Oxyura jamaicensis), is a major problem for the conservation of the endangered white-headed duck (Oxyura leu- cocephala). We report the development of 11 microsatellite markers that can facilitate the identification of hybrids as well as the study of the population structure of both species across their distributions. These markers were

  2. Comparing the genetics of wild and captive populations of White-headed Ducks Oxyura leucocephala : consequences for recovery programmes

    Microsoft Academic Search

    VIOLETA MUÑOZ-FUENTES; ANDY J. GREEN; MICHAEL D. SORENSON

    2008-01-01

    The White-headed Duck is a globally threatened species historically recorded from Spain in the west to China in the east. It has suffered major population declines, local extinctions and range fragmentation. Several projects have attempted to reintroduce captive-bred birds into parts of the former range in Europe, but with little success. Two captive stocks currently exist, one originating from Pakistan

  3. Cross-species amplification of microsatellite markers in Mycteria leucocephala Pennant 1769: molted feathers as successful DNA source.

    PubMed

    Sharma, Bharat Bhushan; Mustafa, Mohd; Sharma, Tusha; Banerjee, Basu Dev; Urfi, Abdul Jamil

    2014-10-01

    DNA from molted feathers is being increasingly used for genetic studies on birds. However, the DNA obtained from such non-invasive sources is often not of enough quantity and quality for isolation of new microsatellite markers. The present study examined the potential of shed feathers of near threatened Painted Stork as a source of its DNA for cross-species amplification of microsatellites. Thirty-one shed feathers of varying conditions ('good' and 'deteriorated') and sizes ('large', 'intermediate' and 'small') collected in a north Indian population were used to isolate DNA by a standard isopropanol method and 11 microsatellite markers already developed in the Wood Stork were screened for amplification. Nine plucked feathers from two dead Painted Storks were also used to compare the DNA yield and amplification success. The DNA yield of feathers varied significantly in relation to the calamus size and condition. Among molted feathers, 'good' and 'large' samples provided more DNA than 'deteriorated' and 'small' ones, respectively. 'Large' plucked feathers yielded more DNA than 'large' molted feathers. DNA was almost degraded in all the samples and ratio of absorbance at 260/280 nm varied from 1.0 to 1.8, indicating impurity in many samples. Independent of DNA yields, all microsatellites were cross-amplified in all kinds of feathers, with > 80% success in different feather categories. It is concluded that the shed feathers can be successfully used to isolate DNA in the Painted Stork and for cross-species amplification of microsatellites. PMID:25345251

  4. Phytochrome Effects in the Nyctinastic Leaf Movements of Albizzia julibrissin and Some Other Legumes 12

    PubMed Central

    Hillman, William S.; Koukkari, Willard L.

    1967-01-01

    Participation of phytochrome is evident in the nyctinastic response of leaves of Albizzia julibrissin (silk-tree), Albizzia lophantha, Leucaena glauca, Poinciana gilliesi and Calliandra inequilatera; closure of excised pairs of pinnules upon darkening is rapid following red illumination and slow following far-red. Under good conditions the difference is obvious within 10 minutes. These observations confirm a report by Fondeville, Borthwick, and Hendricks on the sensitive plant, Mimosa pudica, but indicate that the effect bears no necessary relationship to the anomalous sensitivity of Mimosa. In A. julibrissin, phytochrome control is marked in experiments conducted early in the daily 12-hour light period and appears absent, or nearly so, toward the end of the light period, perhaps due to interaction with an endogenous circadian rhythm. Effects of leaf maturity and of the position of a pinnule-pair within a leaf are also evident. These results are not easily reconciled with hypotheses of phytochrome action through gene activation and nucleic acid synthesis, but are consistent with hypotheses based on permeability changes and membrane properties. The magnitude and reproducibility of the response in A. julibrissin suggest its use as a laboratory exercise; this and related systems should prove valuable for eventual identification of the mechanism of phytochrome action. Images PMID:16656671

  5. Agriculture and nutrition at village level, Underexploited village resources.

    PubMed

    Vietmeyer, N D

    1980-07-28

    Developing country villages contain plants, animals and technologies whose extraordinary potentials are poorly appreciated by scientists. Examples of nutritious village crops that are still largely undeveloped and unappreciated outside their traditional villages are the winged bean, amaranths and the tepary bean. Tropical tree legumes, such as leucaena, grow fast and fix nitrogen and--although barely studied by foresters--are promising sources for village firewood and lumber. There are several animals with great promise for use in villages. The water buffalo is a gentle, productive village resource, neglected by the cow used by Indonesian villagers and unknown elsewhere in the tropics. And Papua New Guinea's new village farms for crocodiles and butterflies graphically demonstrate that wildlife husbandry can be valuable for remote rural areas, despite its neglect by animal science. Among exceptionally useful village technologies, an example is the amazingly efficient cooking system used on the small Indonesian islands of Roti and Sumba, which has so far been described only in Captain Cook's journals. PMID:6106942

  6. Several herbal compounds in Okinawa plants directly inhibit the oncogenic/aging kinase PAK1.

    PubMed

    Nguyen, Binh Cao Quan; Taira, Nozomi; Tawata, Shinkichi

    2014-12-01

    The p21-activated kinase 1 (PAK1) is emerging as a promising therapeutic target, and the search for blockers of this oncogenic/aging kinase would be potentially useful for the treatment of various diseases/disorders in the future. Here, we report for the first time the anti-PAK1 activity of compounds derived from three distinct Okinawa plants. 5,6-Dehydrokawain (DK) and dihydro-5,6-dehydrokawain (DDK) from alpinia inhibited directly PAK1 more strongly than mimosine and mimosinol from leucaena. Cucurbitacin I isolated from bitter gourd/melon also exhibited a moderate anti-PAK1 activity. Hispidin, a metabolite of DK, strongly inhibited PAK1 with the IC50 = 5.7 ?M. The IC50 of three hispidin derivatives (H1-3) for PAK1 inhibition ranges from 1.2 to 2.0 ?M, while mimosine tetrapeptides [mimosine-Phe-Phe-Tyr (MFFY) and mimosine-Phe-Trp-Tyr (MFWY)] inhibit PAK1 at nanomolar level (IC50 of 0.13 and 0.60 ?M, respectively). Thus, we hope these derivatives of hispidin and mimosine could be used as potential leading compounds for developing far more potent anti-PAK1 drugs which would be useful for clinical application in the future. PMID:25639302

  7. Isolation and properties of a ferredoxin from leaves of Sambucus racemosa L.

    PubMed

    Altosaar, I; Bohm, B A; Taylor, I E

    1977-02-01

    Ferredoxin was isolated in good yield from leaves of Sambucus racemosa L. by the following procedure: (1) homogenization in buffered acetone-water (1:1v/v); (2) ion-exchange chromatography on several columns of DEAE-cellulose; and (3) purification by gel filtration with Sephadex G-75. The ultraviolet and visible spectrum showed maxima at 277, 331, 423, and 466 nm. The electron paramagnetic resonance spectrum was centered around g = 1.957. The protein sustained an initial photoreduction rate of 86 mumol NADP per milligram chlorophyll per hour. The amino acid composition was found to be Lys 5, His 2, Arg1, Asx11, Thr5, Ser7, Glx17, Pro6, Gly7, Ala6-7, Cys4, Val8, Ile5, Leu7, Tyr3, Phe2, and Trp1. The molecule had a molecular weight of 10 700 and contained two atoms of iron. The amino-terminal residue was alanine. These properties are highly similar to those of other angiosperm ferredoxins. Sambucus ferredoxin was found to be most closely related to that of Leucaena. PMID:14775

  8. Homestead tree planting in two rural Swazi communities

    USGS Publications Warehouse

    Allen, James A.

    1990-01-01

    Tree planting practices were investigated on a total of 95 homesteads in two communities in rural Swaziland. Information was also collected on socioeconomic characteristics of the homesteads. In both the study areas, Sigombeni and Bhekinkosi, there was considerable variation amongst individual homesteads in size, relative wealth (as indicated by cattle and motor vehicle ownership), and amount and types of trees planted. Eighty-five percent of all homesteads in Sigombeni and 73% in Bhekinkosi had planted at least one tree. Common forms of planting included small woodlots, fruit trees, and ornamentals. Virtually all the woodlots consisted of two introduced wattle species (Acacia mearnsii and A. decurrens). The most commonly planted fruit trees were avocados, bananas, and peaches. No complex or labor-intensive agroforestry practices (such as maize/leucaena intercropping) were observed. There was some evidence that the poorest and newest homesteads were the least likely to have planted any trees and that the richest homesteads were the most likely to have planted woodlots. The results indicate that forestry research and extension efforts should take into account homestead characteristics, and strive to offer a range of tree planting options that vary in input requirements, labor needs, and complexity.

  9. Nitrogen-fixing nodules induced by Agrobacterium tumefaciens harboring Rhizobium phaseoli plasmids.

    PubMed Central

    Martínez, E; Palacios, R; Sánchez, F

    1987-01-01

    Rhizobium phaseoli CFN299 forms nitrogen-fixing nodules in Phaseolus vulgaris (bean) and in Leucaena esculenta. It has three plasmids of 185, 225, and 410 kilobases. The 410-kilobase plasmid contains the nitrogenase structural genes. We have transferred these plasmids to the plasmid-free strain Agrobacterium tumefaciens GMI9023. Transconjugants containing different combinations of the R. phaseoli plasmids were obtained, and they were exhaustively purified before nodulation was assayed. Only transconjugants harboring the 410-kilobase plasmid nodulate P. vulgaris and L. esculenta. Nodules formed by all such transconjugants are able to reduce acetylene. Transconjugants containing the whole set of plasmids from CFN299 nodulate better and fix more nitrogen than the transconjugants carrying only the Sym plasmid. Microscopic analysis of nodules induced by A. tumefaciens transconjugants reveals infected cells and vascular bundles. None of the A. tumefaciens transconjugants, not even the one with the whole set of plasmids from CFN299, behaves in symbiosis like the original R. phaseoli strain; the transconjugants produce fewer nodules and have lower acetylene reduction (25% as compared to the original R. phaseoli strain) and more amyloplasts per nodule. More than 2,000 bacterial isolates from nodules of P. vulgaris and L. esculenta formed by the transconjugants were analyzed by different criteria. Not a single rhizobium could be detected. Our results show that R. phaseoli plasmids may be expressed in the A. tumefaciens background and direct the formation of effective, differentiated nodules. Images PMID:3584072

  10. Effect of Various Organic Matter stimulates Bacteria and Arbuscular Mycorrhizal Fungi Plantations on Eroded Slopes in Nepal

    NASA Astrophysics Data System (ADS)

    Shrestha Vaidya, G.; Shrestha, K.; Wallander, H.

    2009-04-01

    Erosion resulting from landslides is a serious problem in mountainous countries such as Nepal. To restore such sites it is essential to establish plant cover that protects the soil and reduces erosion. Trees and shrubs on the lower hillsides in Nepal form symbiosis with arbuscular mycorrhizal (AM) fungi and these fungi are important for the uptake of mineral nutrients from the soil. In addition, the mycelia formed by these fungi have an important function in stabilizing the soil. The success of plantations of these eroded slopes is therefore highly dependent on the extent of mycorrhizal colonization of the plants. Mycorrhizal fungi growing in symbiosis with plants are essential in this respect because they improve both plant and nutrient uptake and soil structure. We investigated the influence of organic matter and P amendment on recently produced biomass of bacteria and arbuscular mycorrhizal (AM) fungi in eroded slopes in Nepal. Eroded soil mixed with different types of organic matter was placed in mesh bags which were buried around the trees of Bauhinia purpurea and Leucaena diversifolia .This experiment were done in two seasons ( (the wet and the dry season). Signature fatty acids were used to determine bacterial and AM fungal biomass after the six month intervals. The amount and composition of AM fungal spores were analyzed in the mesh bags from the wet and dry seasons. More microbial biomass was produced during wet season than during dry season. Further more, organic matter addition enhanced the production of AM fungal and bacterial biomass during both seasons. The positive influence of organic matter addition on AM fungi could be an important contribution to plant survival, growth and nutrient composition in the soil in plantations on eroded slopes. Different AM spore communities and bacterial profiles were obtained with different organic amendments and this suggests a possible way of selecting for specific microbial communities in the management of eroded sites.

  11. Genomic basis of broad host range and environmental adaptability of Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 which are used in inoculants for common bean (Phaseolus vulgaris L.)

    PubMed Central

    2012-01-01

    Background Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 are ?-Proteobacteria that establish nitrogen-fixing symbioses with a range of legume hosts. These strains are broadly used in commercial inoculants for application to common bean (Phaseolus vulgaris) in South America and Africa. Both strains display intrinsic resistance to several abiotic stressful conditions such as low soil pH and high temperatures, which are common in tropical environments, and to several antimicrobials, including pesticides. The genetic determinants of these interesting characteristics remain largely unknown. Results Genome sequencing revealed that CIAT 899 and PRF 81 share a highly-conserved symbiotic plasmid (pSym) that is present also in Rhizobium leucaenae CFN 299, a rhizobium displaying a similar host range. This pSym seems to have arisen by a co-integration event between two replicons. Remarkably, three distinct nodA genes were found in the pSym, a characteristic that may contribute to the broad host range of these rhizobia. Genes for biosynthesis and modulation of plant-hormone levels were also identified in the pSym. Analysis of genes involved in stress response showed that CIAT 899 and PRF 81 are well equipped to cope with low pH, high temperatures and also with oxidative and osmotic stresses. Interestingly, the genomes of CIAT 899 and PRF 81 had large numbers of genes encoding drug-efflux systems, which may explain their high resistance to antimicrobials. Genome analysis also revealed a wide array of traits that may allow these strains to be successful rhizosphere colonizers, including surface polysaccharides, uptake transporters and catabolic enzymes for nutrients, diverse iron-acquisition systems, cell wall-degrading enzymes, type I and IV pili, and novel T1SS and T5SS secreted adhesins. Conclusions Availability of the complete genome sequences of CIAT 899 and PRF 81 may be exploited in further efforts to understand the interaction of tropical rhizobia with common bean and other legume hosts. PMID:23270491

  12. Current status of plant products reported to inhibit sperm.

    PubMed

    Farnsworth, N R; Waller, D P

    1982-06-01

    This report reviews research on plant-derived agents that prevent sperm production if taken orally by the male or that incapacitate or kill sperm on contact if used vaginally by the female. It would be of great value to develop fertility inhibitors that are totally selective for reproductive systems and enzymes, and there is a possibility that a plant-derived drug may have this effect. Plants that have been studied for their fertility inhibiting effects in the male include: Aristolochia indica L. (Aristolochiaceae); Azadirachta indica A. Juss (Meliaceae); Balanites roxburghii Planch. (Zygophyllaceae); Calotropis procera (Ait) R.Br. (Asclepiadaceae); Carica papaya L. (Caricaceae); Catharanthus roseus (L.) G. Don (Apocynaceae); Dieffenbachia seguine (Jacquin) Schott. (Araceae); Ecaballium elaterium A. Richard (Cucurbitaceae); Gossypium species (Malvaceae); Hibiscus rosa-sinensis L. (Malvaceae); Hippophae salicifolia D. Don (Elaeagnaceae); Leucaena glauca (L.) Benth. (Leguminosae); Lonicera ciliosa Poir. (Caprifoliaceae); Lupinus termis Forsk. (Leguminosae); Malvaviscus conzattii Greenm. (Malvaceae); Momordica charantia L. (Curcurbitaceae); Ocimum sanctum L. (Labiatae); Prunus emarginata Walp. (Rosaceae); and Withania somnifera (L.) Dunal (Solanaceae). A large number of plants have been randomly selected and screened for spermicidal activity "in vitro" and several seem promising. Those species found to be active and the nature of the active principle(s), when known, are presented in a table as are plant-derived chemical substances of known or partially known structure reported to be spermicidal "in vitro." Plants warrant systematic study as potential sources of sperm-agglutinating compounds. Of 1600 Indian plants tested, 90 showed positive semen coagulating properties. There seems to be a lack of correlation among experimental results obtained by different groups of investigators, between data obtained "in vitro" and "in vivo," and between experimental results and information found in folklore. Factors complicating the adequate assessment of plants affecting male fertility are inadequate numbers of vehicle-treated controls, poor experimental design, problems related to insolubility of crude plant extracts, variation in routes of administration, diversity in reproductive function and control among various laboratory species, and problems in identifying plant names consistently. PMID:12179631

  13. Soil carbon sequestration in rainfed production systems in the semiarid tropics of India.

    PubMed

    Srinivasarao, Ch; Lal, Rattan; Kundu, Sumanta; Babu, M B B Prasad; Venkateswarlu, B; Singh, Anil Kumar

    2014-07-15

    Severe soil organic carbon (SOC) depletion is a major constraint in rainfed agroecosystems in India because it directly influences soil quality, crop productivity and sustainability. The magnitude of soil organic, inorganic and total carbon stocks in the semi-arid bioclimate is estimated at 2.9, 1.9 and 4.8 Pg respectively. Sorghum, finger millet, pearl millet, maize, rice, groundnut, soybean, cotton, food legumes etc. are predominant crop production systems with a little, if any, recycling of organic matter. Data from the long term experiments on major rainfed production systems in India show that higher amount of crop residue C input (Mg/ha/y) return back to soil in soybean-safflower (3.37) system practiced in Vertisol region of central India. Long term addition of chemical fertilizer and organic amendments improved the SOC stock. For every Mg/ha increase in SOC stock in the root zone, there occurs an increase in grain yield (kg/ha) of 13, 101, 90, 170, 145, 18 and 160 for groundnut, finger millet, sorghum, pearl millet, soybean and rice, respectively. Long-term cropping without using any organic amendment and/or mineral fertilizers can severely deplete the SOC stock which is the highest in groundnut-finger millet system (0.92 Mg C/ha/y) in Alfisols. Some agroforestry systems also have a huge potential of C sequestration to the extent of 10Mg/ha/y in short rotation eucalyptus and Leucaena plantations. The critical level of C input requirements for maintaining SOC at the antecedent level ranges from 1.1 to 3.5 Mg C/ha/y and differs among soil type and production systems. National level policy interventions needed to promote sustainable use of soil and water resources include prohibiting residue burning, reducing deforestation, promoting integrated farming systems and facilitating payments for ecosystem services. A wide spread adoption of these measures can improve soil quality through increase in SOC sequestration and improvement in agronomic productivity of rainfed agroecosystems. PMID:24210647

  14. 75 FR 9281 - General Provisions; Revised List of Migratory Birds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ...leucocephala (10). Pipit, Water, Anthus spinoletta (7...family is protected anywhere and everywhere that it might occur in the...Commission, South Florida Water Management District, Everglades...spragueii Tree, Anthus trivialis [Water (see American)]...

  15. Arid Land Research and Management, 15:359 370, 2001 Copyright # 2001 Taylor & Francis

    E-print Network

    Bruns, Tom

    -4982/01 $12.00 .00 Optimizing Solution P Concentration in a Peat-Based Medium for Producing Mycorrhizal concentration of the amended medium for mycorrhizal activity will enhance its usefulness for raising mycorrhizal concentration for mycorrhizal development on roots of our indicator plant L eucaena leucocephala grown

  16. Data Set Incongruence and Correlated Character Evolution: An Example of Functional Convergence in the Hind-Limbs of Stifftail Diving Ducks

    E-print Network

    Afton, Alan D.

    genera, monophyly of Oxyura and its sister group relationship with Nomonyx are strongly sup- ported. Within Oxyura, Old World species (O. australis, O. leucocephala, O. maccoa) appear to form a clade, with New World species (O. jamaicensis, O. vittata) branching basally. Incongruence between molecules

  17. A model for the management of the invasive ruddy duck to reduce interbreeding pressure on the white-headed duck

    Microsoft Academic Search

    Graham C. Smith; Iain Henderson

    2007-01-01

    Non-native species are considered the second most important threat to global biodiversity after habitat loss and are a leading cause of animal extinctions. The North American ruddy duck Oxyura jamaicensis established a feral population in the UK over 40 years ago, and is now endangering the globally threatened white-headed duck Oxyura leucocephala through hybridisation. We utilised a simple Monte Carlo

  18. The ruddy duck Oxyura jamaicensis in Europe: natural colonization or human introduction?

    Microsoft Academic Search

    VIOLETA MUÑOZ-FUENTES; ANDY J. G REEN; MICHAEL D. S ORENSON; JUAN J. N EGRO; CARLES VILÀ

    2006-01-01

    Native to North America, ruddy ducks Oxyura jamaicensis now occur in 21 countries in the western Palaearctic (including Iceland) and their expanding population threatens the native white-headed duck, Oxyura leucocephala , through hybridization and possibly competition for food and nest sites. We used mitochondrial DNA sequences and nuclear microsatellites to test whether the European ruddy duck population is descended solely

  19. Ocells rars a Catalunya. Informe del Comitè Avifaunístic de Catalunya. 2005, 2006, 2007 i 2008

    Microsoft Academic Search

    Ferran López; Jordi Clavell

    Rare birds in Catalonia. Report of the Catalan Avifauna Committee. 2005, 2006, 2007 & 2008 .ThesecondreportofCatalanAvifaunaCommitteeincludesfirstaccep - tedrecordsbyourcommittee: Branta bernicla, Aythya marila, Bucephala clangula, Oxyu - ra leucocephala, Oceanodroma leucorhoa, Podiceps auritus, Elanus caeruleus, Aegypius mona- chus, Circus macrourus, Aquila adalberti, Otis tarda, Calidris melanotos, Phalaropus tricolor, Larus atricilla, Larus delawarensis, Larus cachinnans, Alle alle, Anthus richardi, Anthus petro -

  20. Status and conservation of parrots and parakeets in the Greater Antilles, Bahama Islands, and Cayman Islands

    USGS Publications Warehouse

    Wiley, J.W.

    1991-01-01

    In the 1490s a minimum of 28 species of psittacines occurred in the West Indies. Today, only 43% (12) of the species survive. All macaws and most parakeet species have been lost. Although the surviving parrot fauna of the Greater Antilles, Cayman Islands, and Bahama Islands has fared somewhat better than that of the Lesser Antilles, every species has undergone extensive reductions of populations and all but two have undergone extensive reductions in range, mostly as a result of habitat loss, but also from persecution as agricultural pests, conflicts with exotic species, harvesting for pets, and natural disasters. The Cayman Brac Parrot Amazona leucocephala hesterna with its tiny population (less than 150 individuals in the wild) and range, and the Puerto Rican Parrot A. vittata, with about 22-23 birds in the wild and 56 individuals in captivity, must be considered on the verge of extinction and in need of (in the latter's case, continuing) aggressive programmes of research and management. Other populations declining in numbers and range include the Yellow-billed Amazona collaria, and Black-billed A. agilis Parrots of Jamaica, Hispaniolan Parakeet Aratinga chloroptera, Hispaniolan Parrot Amazona ventralis, Cuban Parrot A. leucocephala leucocephala and, most seriously, Cuban Parakeet Aratinga euops. The population of the Grand Cayman Parrot (Amazona leucocephala caymanensis), although numbering only about 1,000 birds, appears stable and the current conservation programme gives hope for the survival of the race. An active conservation and public education programme has begun for the Bahama Parrot A. l. bahamensis, which still occurs in good numbers on Great Inagua Island, but is threatened on Abaco Island. Recommendations for conservation of parrots and parakeets in the region include (1) instituting long-term programmes of research to determine distribution, status, and ecology of each species; (2) developing conservation programmes through education and management approaches that are culturally, politically, and economically sensitive to the region; and (3) providing and protecting habitat within suitably sized reserves.

  1. Is homoplasy or lineage sorting the source of incongruent mtdna and nuclear gene trees in the stiff-tailed ducks (Nomonyx-Oxyura)?

    PubMed

    McCracken, Kevin; Sorenson, Michael

    2005-02-01

    We evaluated the potential effects of homoplasy, ancestral polymorphism, and hybridization as obstacles to resolving phylogenetic relationships within Nomonyx-Oxyura stiff-tailed ducks (Oxyurinae; subtribe Oxyurina). Mitochondrial DNA (mtDNA) control region sequences from 94 individuals supported monophyly of mtDNA haplotypes for each of the six species and provided no evidence of extant incomplete lineage sorting or inter-specific hybridization. The ruddy ducks (O. j. jamaicensis,O. j. andina, O. j. ferruginea) are each others' closest relatives, but the lack of shared haplotypes between O. j. jamaicensis and O. j. ferruginea suggests long-standing historical isolation. In contrast, O. j. andina shares haplotypes with O. j. jamaicensis and O. j. ferruginea, which supports Todd's (1979) and Fjeldså's (1986) hypothesis that O. j. andina is an intergrade or hybrid subspecies of O. j. jamaicensis and O. j. ferruginea. Control region data and a much larger data set composed of approximately 8800 base pairs of mitochondrial and nuclear sequence for each species indicate that the two New World species, O. vittata and O. jamaicensis, branch basally within Oxyura. A clade of three Old World species (O. australis, O. maccoa, O. leucocephala) is well supported, but different loci and also different characters within the mtDNA data support three different resolutions of the Old World clade, yielding an essentially unresolved trichotomy. Fundamentally different factors limited the resolution of the mtDNA and nuclear gene trees. Gene trees for most nuclear loci were unresolved due to slow rates of mutation and a lack of informative variation, whereas uncertain resolution of the mtDNA gene tree was due to homoplasy. Within the mtDNA, approximately equal numbers of characters supported each of three possible resolutions. Parametric and nonparametric bootstrap analyses suggest that resolution of the mtDNA tree based on ~4300 bp per taxon is uncertain but that complete mtDNA sequences would yield a fully resolved gene tree. A short internode separating O. leucocephala from (O. australis, O. maccoa) in the best mtDNA tree combined with long terminal branches and substantial rate variation among nucleotide sites allowed the small number of changes occurring on the internode to be obscured by homoplasy in a significant portion of simulated data sets. Although most nuclear loci were uninformative, two loci supported a resolution of the Old World clade (O. maccoa, O. leucocephala) that is incongruent with the best mtDNA tree. Thus, incongruence between nuclear and mtDNA trees may be due to random sorting of ancestral lineages during the short internode, homoplasy in the mtDNA data, or both. The Oxyura trichotomy represents a difficult though likely common problem in molecular systematics. Given a short internode, the mtDNA tree has a greater chance of being congruent with the history of speciation because its effective population size (N(e)) is one-quarter that of any nuclear locus, but its resolution is more likely to be obscured by homoplasy. In contrast, gene trees for more slowly evolving nuclear loci will be difficult to resolve due to a lack of substitutions during the internode, and when resolved are more likely to be incongruent with the species history due to the stochastic effects of lineage sorting. We suggest that researchers consider first whether independent gene trees are adequately resolved and then whether those trees are congruent with the species history. In the case of Oxyura, the answer to both questions may be no. Complete mtDNA sequences combined with data from a very large number of nuclear loci may be the only way to resolve such trichotomies. PMID:15805009

  2. Normal yeast flora of the upper digestive tract of some wild columbids

    USGS Publications Warehouse

    Kocan, R.M.; Hasenclever, H.F.

    1972-01-01

    Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

  3. The ruddy duck Oxyura jamaicensis in Europe: natural colonization or human introduction?

    PubMed

    Muñoz-Fuentes, Violeta; Green, Andy J; Sorenson, Michael D; Negro, Juan J; Vilà, Carles

    2006-05-01

    Native to North America, ruddy ducks Oxyura jamaicensis now occur in 21 countries in the western Palaearctic (including Iceland) and their expanding population threatens the native white-headed duck, Oxyura leucocephala, through hybridization and possibly competition for food and nest sites. We used mitochondrial DNA sequences and nuclear microsatellites to test whether the European ruddy duck population is descended solely from the captive population in the UK, which traces to seven individuals imported from the USA in 1948, or, alternatively, has been augmented by natural dispersal of birds from North America. Limited genetic diversity in the European population is consistent with a founder population as small as seven birds. In addition, shifts in allele frequencies at several loci, presumably due to genetic drift in the founding population, result in significant differentiation between the European and North American populations. Despite the recent separation of these populations, almost all individuals could be unambiguously assigned based on their composite genotypes, to one of two distinct populations, one comprising all of the European ruddy ducks we sampled (including those from Iceland and captive birds in the UK) and the other comprising all North American samples. Our results confirm that the European ruddy duck population is likely to derive solely from the captive population in the UK and we find no evidence of recent arrivals from North America or of admixture between ruddy ducks from Europe and North America. PMID:16629802

  4. Hybridization between white-headed ducks and introduced ruddy ducks in Spain.

    PubMed

    Muñoz-Fuentes, V; Vilà, C; Green, A J; Negro, J J; Sorenson, M D

    2007-02-01

    The ruddy duck, Oxyura jamaicensis, was introduced to Great Britain in the mid-20th century and has recently spread to other Western European countries. In Spain, ruddy ducks hybridize with the globally endangered white-headed duck, Oxyura leucocephala. We assessed the effects of hybridization on the Spanish white-headed ducks, which constitute 25% of the global population of this species, using a panel of eight nuclear intron markers, 10 microsatellite loci, and mtDNA control region sequences. These data allowed parental individuals, F(1) hybrids, and the progeny of backcrossing to be reliably distinguished. We show that hybrids between the two species are fertile and produce viable offspring in backcrosses with both parental species. To date, however, we found no extensive introgression of ruddy duck genes into the Spanish white-headed duck population, probably due to the early implementation of an effective ruddy duck and hybrid control programme. We also show that genetic diversity in the expanding European ruddy duck population, which was founded by just seven individuals, exceeds that of the native Spanish white-headed duck population, which recently recovered from a severe bottleneck. Unless effective control of ruddy ducks is continued, genetic introgression will compromise the unique behavioural and ecological adaptations of white-headed ducks and consequently their survival as a genetically and evolutionary distinct species. PMID:17257118

  5. Estimation of density and population size and recommendations for monitoring trends of Bahama parrots on Great Abaco and Great Inagua

    USGS Publications Warehouse

    Rivera-Milan, F. F.; Collazo, J.A.; Stahala, C.; Moore, W.J.; Davis, A.; Herring, G.; Steinkamp, M.; Pagliaro, R.; Thompson, J.L.; Bracey, W.

    2005-01-01

    Once abundant and widely distributed, the Bahama parrot (Amazona leucocephala bahamensis) currently inhabits only the Great Abaco and Great lnagua Islands of the Bahamas. In January 2003 and May 2002-2004, we conducted point-transect surveys (a type of distance sampling) to estimate density and population size and make recommendations for monitoring trends. Density ranged from 0.061 (SE = 0.013) to 0.085 (SE = 0.018) parrots/ha and population size ranged from 1,600 (SE = 354) to 2,386 (SE = 508) parrots when extrapolated to the 26,154 ha and 28,162 ha covered by surveys on Abaco in May 2002 and 2003, respectively. Density was 0.183 (SE = 0.049) and 0.153 (SE = 0.042) parrots/ha and population size was 5,344 (SE = 1,431) and 4,450 (SE = 1,435) parrots when extrapolated to the 29,174 ha covered by surveys on Inagua in May 2003 and 2004, respectively. Because parrot distribution was clumped, we would need to survey 213-882 points on Abaco and 258-1,659 points on Inagua to obtain a CV of 10-20% for estimated density. Cluster size and its variability and clumping increased in wintertime, making surveys imprecise and cost-ineffective. Surveys were reasonably precise and cost-effective in springtime, and we recommend conducting them when parrots are pairing and selecting nesting sites. Survey data should be collected yearly as part of an integrated monitoring strategy to estimate density and other key demographic parameters and improve our understanding of the ecological dynamics of these geographically isolated parrot populations at risk of extinction.

  6. The Nodulation of Alfalfa by the Acid-Tolerant Rhizobium sp. Strain LPU83 Does Not Require Sulfated Forms of Lipochitooligosaccharide Nodulation Signals?

    PubMed Central

    Torres Tejerizo, Gonzalo; Del Papa, María Florencia; Soria-Diaz, M. Eugenia; Draghi, Walter; Lozano, Mauricio; Giusti, María de los Ángeles; Manyani, Hamid; Megías, Manuel; Gil Serrano, Antonio; Pühler, Alfred; Niehaus, Karsten; Lagares, Antonio; Pistorio, Mariano

    2011-01-01

    The induction of root nodules by the majority of rhizobia has a strict requirement for the secretion of symbiosis-specific lipochitooligosaccharides (nodulation factors [NFs]). The nature of the chemical substitution on the NFs depends on the particular rhizobium and contributes to the host specificity imparted by the NFs. We present here a description of the genetic organization of the nod gene cluster and the characterization of the chemical structure of the NFs associated with the broad-host-range Rhizobium sp. strain LPU83, a bacterium capable of nodulating at least alfalfa, bean, and Leucena leucocephala. The nod gene cluster was located on the plasmid pLPU83b. The organization of the cluster showed synteny with those of the alfalfa-nodulating rhizobia, Sinorhizobium meliloti and Sinorhizobium medicae. Interestingly, the strongest sequence similarity observed was between the partial nod sequences of Rhizobium mongolense USDA 1844 and the corresponding LPU83 nod genes sequences. The phylogenetic analysis of the intergenic region nodEG positions strain LPU83 and the type strain R. mongolense 1844 in the same branch, which indicates that Rhizobium sp. strain LPU83 might represent an early alfalfa-nodulating genotype. The NF chemical structures obtained for the wild-type strain consist of a trimeric, tetrameric, and pentameric chitin backbone that shares some substitutions with both alfalfa- and bean-nodulating rhizobia. Remarkably, while in strain LPU83 most of the NFs were sulfated in their reducing terminal residue, none of the NFs isolated from the nodH mutant LPU83-H were sulfated. The evidence obtained supports the notion that the sulfate decoration of NFs in LPU83 is not necessary for alfalfa nodulation. PMID:20971905

  7. Data set incongruence and correlated character evolution: An example of functional convergence in the hind-limbs of stifftail diving ducks

    USGS Publications Warehouse

    McCracken, K.G.; Harshman, J.; Mcclellan, D.A.; Afton, A.D.

    1999-01-01

    The unwitting inclusion of convergent characters in phylogenetic estimates poses a serious problem for efforts to recover phylogeny. Convergence is not inscrutable, however, particularly when one group of characters tracks phylogeny and another set tracks adaptive history. In such cases, convergent characters may be correlated with one or a few functional anatomical units and readily identifiable by using comparative methods. Stifftail ducks (Oxyurinae) offer one such opportunity to study correlated character evolution and function in the context of phylogenetic reconstruction. Morphological analyses place stifftail ducks as part of a large clade of diving ducks that includes the sea ducks (Mergini), Hymenolaimus, Merganetta, and Tachyeres, and possibly the pochards (Aythyini). Molecular analyses, on the other hand, place stifftails far from other diving ducks and suggest, moreover, that stifftails are polyphyletic. Mitochondrial cytochrome b gene sequences of eight stifftail species traditionally supposed to form a clade were compared with each other and with sequences from 50 other anseriform and galliform species. Stifftail ducks are not the sister group of sea ducks but lie outside the typical ducks (Anatinae). Of the four traditional stifftail genera, monophyly of Oxyura and its sister group relationship with Nomonyx are strongly supported. Heteronetta probably is the sister group of that clade, but support is weak. Biziura is not a true stifftail. Within Oxyura, Old World species (O. australis, O. leucocephala, O. mnccoa) appear to form a clade, with New World species (O. jamaicensis, O. vittata) branching basally. Incongruence between molecules and morphology is interpreted to be the result of adaptive specialization and functional convergence in the hind limbs of Biziura and true stifftails. When morphological characters are divided into classes, only hind-limb characters are significantly in conflict with the molecular tree. Likewise, null models of synonymous and nonsynonymous substitution based on patterns of codon-degeneracy and chemical dissimilarity indicate that the nucleotide and amino acid changes postulated by the molecular tree are more plausible than those postulated by the morphological tree. These findings teach general lessons about the utility of highly adaptive characters (in particular those related to foraging ecology) and underscore the problems that convergence can pose for attempts to recover phylogeny. They also demonstrate how the concept of natural data partitions and simple models of evolution (e.g., parsimony, likelihood, neutrality) can be used to test the accuracy of independent phylogenetic estimates and provide arguments in favor of one tree topology over another.

  8. Data set incongruence and correlated character evolution: an example of functional convergence in the hind-limbs of stifftail diving ducks.

    PubMed

    McCracken, K G; Harshman, J; McClellan, D A; Afton, A D

    1999-12-01

    The unwitting inclusion of convergent characters in phylogenetic estimates poses a serious problem for efforts to recover phylogeny. Convergence is not inscrutable, however, particularly when one group of characters tracks phylogeny and another set tracks adaptive history. In such cases, convergent characters may be correlated with one or a few functional anatomical units and readily identifiable by using comparative methods. Stifftail ducks (Oxyurinae) offer one such opportunity to study correlated character evolution and function in the context of phylogenetic reconstruction. Morphological analyses place stifftail ducks as part of a large clade of diving ducks that includes the sea ducks (Mergini), Hymenolaimus, Merganetta, and Tachyeres, and possibly the pochards (Aythyini). Molecular analyses, on the other hand, place stifftails far from other diving ducks and suggest, moreover, that stifftails are polyphyletic. Mitochondrial cytochrome b gene sequences of eight stifftail species traditionally supposed to form a clade were compared with each other and with sequences from 50 other anseriform and galliform species. Stifftail ducks are not the sister group of sea ducks but lie outside the typical ducks (Anatinae). Of the four traditional stifftail genera, monophyly of Oxyura and its sister group relationship with Nomonyx are strongly supported. Heteronetta probably is the sister group of that clade, but support is weak. Biziura is not a true stifftail. Within Oxyura, Old World species (O. australis, O. leucocephala, O. maccoa) appear to form a clade, with New World species (O. jamaicensis, O. vittata) branching basally. Incongruence between molecules and morphology is interpreted to be the result of adaptive specialization and functional convergence in the hind limbs of Biziura and true stifftails. When morphological characters are divided into classes, only hind-limb characters are significantly in conflict with the molecular tree. Likewise, null models of synonymous and nonsynonymous substitution based on patterns of codon-degeneracy and chemical dissimilarity indicate that the nucleotide and amino acid changes postulated by the molecular tree are more plausible than those postulated by the morphological tree. These findings teach general lessons about the utility of highly adaptive characters (in particular those related to foraging ecology) and underscore the problems that convergence can pose for attempts to recover phylogeny. They also demonstrate how the concept of natural data partitions and simple models of evolution (e.g., parsimony, likelihood, neutrality) can be used to test the accuracy of independent phylogenetic estimates and provide arguments in favor of one tree topology over another. PMID:12066296

  9. N-P-K balance in a milk production system on a C. nlemfuensis grassland and a biomass bank of P. purpureum CT-115 clone

    NASA Astrophysics Data System (ADS)

    Crespo, G.; Rodriguez, I.; Martinez, O.

    2009-04-01

    In very intensive milk production systems in Europe and America with the use of high amounts of chemical fertilizers, the nutrient recycling models consider the losses by leaching and N volatilization, as well as the hydro physical characteristics of the soil affecting the performance of this element (10; 6). However, in more extensive milk production systems, low input agriculture forming the natural cycle occurring within each farm, is of vital importance to potentate nutrient recycling for a stable animal production. The objective is the determination of the values of N, P and K inputs and outputs in a dairy farm with a sward composed by 60% of C. nlemfuensis and 40% of P. purpureum CT-115, associated with legumes in 28% of the area and the balance of these nutrients in the system using the "Recycling" software proposed by Crespo et al (2007). The grassland covered an area of 53.4 ha, composed by C. nlemfuensis (60%), P. purpureum CT-115 (40%) and L. leucocephala and C. cajan legumes intercropped in 28% of the area. The dairy herd consisted of 114 cows, 35 replacement heifers and 24 calves. There was a milk yield of 100 000 litters and the animals consumed 825 t DM from pastures and 75.1 t DM from other supplementary feeds. Nutrients extracted by pastures, nutrients intake by animals from pastures, symbiotically N fixation by legumes and N, P and K determinations outside the system due to animal production were determined (3-11). Volatilized ammonia, nutrient input and litter accumulated in the paddocks were measured once each season of the year. In the whole system the balance indicates negative values of N, P and K. Out of the total amount of nutrients consumed, animals used only 16 kg N, 5 Kg P and 4 Kg K for milk production, LW gain and calf production, the remainder returned to the system through excretions. Hence, more than 90% of the N and K, and approximately 81% of the P consumed by the animals were recycled to the system through the excretions. These results agree with those reported by Jarvis (1993) and Cadish et al (1994). However, 40% of the excretions occurred in the shade buildings and milking parlours ant thus these nutrients did not recycle in the system. An important internal recycling mechanism, especially for nitrogen and potassium, is their remobilization by the rejected pasture to re-use them for the regrowth activity. This is of particular interest in CT-115 Bank, since stems of CT-115 plants left after grazing remobilize an important amount of these nutrients, guarantee a favourable pasture regrowth (Martinez 1996). The return of all the excretion to the grassland is recommended as well as increasing the area of legumes to attain a satisfactory balance of N, P and K in the system. Further studies must consider maintenance fertilization, nutrient losses due to leaching and denitrification, as well as variation of the stable OM in the soil and the influence of hydro physical properties in the recycling process. The "Recycling" software was effective to determine the balance of nutrients in the dairy farm. Cadish, G., Schunke, R.N & Giller, K.E. 1994. Nitrogen cycling in a pure grass pasture and a grass-legume mixture on a red latosol in Brazil. Tropical Grasslands 28:43. Crespo G. y Rodríguez, I. 2006. Contribución al conocimiento del reciclaje de los nutrientes en el sistema suelo-pasto-animal. Instituto de Ciencia Animal, Editorial EDICA, La Habana, Cuba, 94 pp. Hirata, M., Sugimoto, Y.G & Ueno, M.1991. Use of a mathematical model to evaluate the effects of dung from grazing animals on pasture production. J. Japan Grassld. Sci. 37:303.