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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

EFFECTS OF HIGH AND LOW IRRIGATION ON SYMBIOTIC NITROGEN FIXATION ON COWPEA (VIGNA UNGUICULATA (L.) WALP.)

Mohamed, Ibrahim Elbashir January 1982 (has links)
No description available.
82

Deposition and growth of various nanomaterials at nanostructured interfaces

Bock, Eva. January 2009 (has links)
Heidelberg, Univ., Diss., 2008.
83

Cowpea seed coats and their extracts phenolic composition and use as antioxidants in sunflower oil /

Mokgope, Lethabo B. January 2006 (has links)
Thesis (M.Inst.Agrar.)(Food production and processing)--University of Pretoria, 2006. / Includes bibliographical references. Available on the Internet via the World Wide Web.
84

Respostas fisiológicas e bioquímicas do feijão-de-corda [Vigna unguiculata (L.) Walp.] submetido ao estresse hídrico, infectado com o vírus do mosaico severo do caupi, e sob pressão dos dois estresses combinados / Hysiological and biochemical responses of cowpea [Vigna unguiculata (l.) walp.] under water stress, infected with cowpea severe mosaic virus, and under pressure of combined stresses

Silva, Rodolpho Glauber Guedes January 2016 (has links)
SILVA, Rodolpho Glauber Guedes. Respostas fisiológicas e bioquímicas do feijão-de-corda [Vigna unguiculata (L.) Walp.] submetido ao estresse hídrico, infectado com o vírus do mosaico severo do caupi, e sob pressão dos dois estresses combinados. 2016. 137 f. Tese (Doutorado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2016. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-28T15:41:58Z No. of bitstreams: 1 2016_tese_rggsilva.pdf: 2259649 bytes, checksum: 18f9f4ca9a43a3bfd289cedfbacbd968 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T14:43:34Z (GMT) No. of bitstreams: 1 2016_tese_rggsilva.pdf: 2259649 bytes, checksum: 18f9f4ca9a43a3bfd289cedfbacbd968 (MD5) / Made available in DSpace on 2016-08-02T14:43:34Z (GMT). No. of bitstreams: 1 2016_tese_rggsilva.pdf: 2259649 bytes, checksum: 18f9f4ca9a43a3bfd289cedfbacbd968 (MD5) Previous issue date: 2016 / Cowpea (Vigna unguiculata) is a legume (Fabaceae) with high nutritional value grown in Brazil. However, biotic and abiotic factors are responsible for causing significant losses to the growth and yield of leguminous plants. Cowpea mosaic severe virus (CPSMV) is one of the more severe problems affecting cowpea production in Brazil. Also, cowpea are mainly grown in regions where rainfall is low, thus water deficit is quite common. This stress promotes substantial negative impact on growth and development of plants, resulting in decreased of biomass production. Under field conditions, the stresses mentioned above can occur both individually and simultaneously. Therefore, this work aimed to study the responses of cowpea (CE-31 genotype, syn. Pitiuba) subjected to water deficit, infected with CPSMV and under pressure of the two combined stresses. Under these conditions, enzyme kinetics of antioxidant protein (superoxide dismutase, catalase and ascorbate peroxidase) and PR-proteins (glucanase, chitinase and guaiacol peroxidase) as well as hydrogen peroxide dosage and quantification of CPSMV in cowpea leaves were performed. In addition, differentially accumulated proteins from cowpea leaves subjected to these stresses were identified and quantified by LC-MS/MS. Viral infection did not affect the majority of physiological parameters. Already water deficit contributed to the decrease in net photosynthesis, transpiration and stomatal conductance. At 6 days after CPSMV inoculation, the virus did not worsen the negative effects of drought. The results revealed that the enzyme kinetics of the responses was changed across different ways when the stress imposed individually or simultaneously and the presence of water deficit favored viral infection after 2 days of CPSMV inoculation. The proteomic analysis revealed 117 differentially accumulated proteins belonging to different categories according to the physiological functions: energy and metabolism, photosynthesis, protein metabolism, redox homeostasis, regulation factors and RNA processing, response to stress, plant defense and others. These results are important for understanding the cellular mechanisms that operate in cowpea (CE-31 genotype), when subjected to water deficit, CPSMV infection and both combined stresses. / O feijão-de-corda (Vigna unguiculata) é uma das principais leguminosas cultivadas no Brasil. Entretanto, devido à presença de fatores bióticos e abióticos são geradas perdas significativas na produtividade desta cultura. O Vírus do Mosaico Severo do Caupi (CPSMV) tem atacado com grande frequência os cultivos brasileiros. Além disso, devido o feijão-de-corda ser cultivado em regiões onde os índices pluviométricos são baixos, a deficiência hídrica é bastante comum. Esse estresse promove impacto negativo substancial no crescimento e desenvolvimento das plantas, resultando em diminuição na produção de biomassa. Em condições de campo, os estresses mencionados acima podem ocorrer tanto individualmente quanto simultaneamente. Portanto, o presente estudo teve como objetivo estudar as respostas do feijão-de-corda (genótipo CE-31, sin. Pitiúba) submetido ao estresse hídrico, infectado com o CPSMV e sob pressão dos dois estresses combinados. Sob essas condições, a cinética enzimática de proteínas antioxidantes (superóxido dismutase, catalase e ascorbato peroxidase) e PR-proteínas (glucanase, quitinase e guaiacol peroxidase), bem como a dosagem de peróxido de hidrogênio e quantificação do CPSMV em folhas de feijão-de-corda foram realizadas. Além disso, proteínas diferencialmente acumuladas em folhas de feijão-de-corda submetidas à esses estresses foram quantificadas e identificadas por LC-MS/MS e bancos de dados disponíveis. A infecção viral não alterou a maioria dos parâmetros fisiológicos. Já a deficiência hídrica contribuiu para a diminuição da fotossíntese líquida, transpiração e condutância estomática. Até 6 dias após inoculação do CPSMV, o vírus não agravou os efeitos negativos da seca. Os resultados da cinética enzimática revelaram que as respostas são alteradas de formas diferentes frente aos estresses quando impostos individualmente ou simultaneamente e que a presença do estresse hídrico favoreceu a infecção viral após 2 dias de inoculação. A análise proteômica revelou 117 proteínas diferencialmente acumuladas pertencentes a diferentes categorias de acordo com as funções fisiológicas: energia e metabolismo, fotossíntese, metabolismo de proteínas, homeostase redox, fatores de regulação e processamento de RNA, resposta ao estresse, defesa de plantas e outras. Estes resultados são importantes para a compreensão dos mecanismos celulares que atuam no feijão-de-corda, genótipo CE-31, quando submetido ao estresse hídrico, à infecção pelo CPSMV e a ambos os estresses de forma combinada.
85

AnÃlise proteÃmica diferencial da interaÃÃo incompatÃvel entre o feijÃo-de-corda e o fitopatÃgeno Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. / Differential incompatible interaction between bean-to-string and pathogen Colletotrichum gloeosporioides (Penz.) Penz proteomic analysis. & Sacc.

Hudson Fernando Nunes Moura 16 August 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O feijÃo-de-corda [Vigna unguiculata (L.) Walp.] pertence à famÃlia Fabaceae e à bastante utilizado na alimentaÃÃo humana como fonte de proteÃnas, carboidratos, vitaminas e minerais. Dentre as principais caracterÃsticas do feijÃo-de-corda, seu elevado conteÃdo proteico e a boa tolerÃncia Ãs condiÃÃes de baixa disponibilidade de Ãgua nos solos, altas temperaturas e relativa tolerÃncia à salinidade, condiÃÃes tÃpicas das regiÃes semi-Ãridas do nordeste do Brasil, sÃo algumas das que podem ser citadas. Entretanto, apesar da considerÃvel capacidade de tolerÃncia Ãs diferentes condiÃÃes de estresses, parte da produtividade do feijÃo-de-corda à ameaÃada pela aÃÃo de diversos fitopatÃgenos, dentre os quais se destacam os fungos como maiores causadores de patologias desta cultura, a exemplo da Antracnose, resultado da infecÃÃo por C. gloeosporioides, caracterizada por manchas marrom-avermelhadas nas nervuras foliares que podem se prolongar por todos os ÃrgÃos da planta hospedeira. Felizmente, o feijÃo-de-corda possui cultivares que apresentam caracterÃsticas diferenciadas de resistÃncia, frente ao C. gloeosporioides, no que concerne à ativaÃÃo das defesas da planta em interaÃÃes ditas incompatÃveis, haja vista que o patÃgeno nÃo consegue deliberar a infecÃÃo. Partindo dessa premissa, à vÃlido mencionar que grande parte dos mecanismos de resistÃncia de plantas aos patÃgenos està relacionada com a expressÃo gÃnica diferencial de proteÃnas que funcionariam como marcadores de defesa em resposta à infecÃÃo. Nesse sentido, esse estudo propÃe a anÃlise proteÃmica diferencial da interaÃÃo incompatÃvel (resistÃncia) entre plantas de feijÃo-de-corda, genÃtipo BR3, e o isolado LPVD-1, do fungo C. gloeosporioides a fim de identificar possÃveis marcadores proteicos determinantes da resistÃncia para esse patossistema. Por meio da utilizaÃÃo da abordagem Eletroforese Bidimensional em combinaÃÃo com Espectrometria de Massas ESI-Q-TOF MS/MS, foram identificadas 118 proteÃnas diferencialmente expressas, considerando proteÃnas superexpressas (102) e subexpressas (16), envolvidas em diversos processos celulares, tais como: Metabolismo energÃtico, fotossÃntese, metabolismo de proteÃnas e Ãcidos nucleicos, resposta ao estresse, transporte celular, homeostase redox, sinalizaÃÃo e defesa, com destaque para expressÃo das proteÃnas PR-10 (relacionada à patogÃnese), Remorina e Ascorbato peroxidase que apresentaram alteraÃÃes significativas em todos os tempos experimentais testados. Esses achados demonstram a complexidade dos mecanismos envolvidos durante a resistÃncia vegetal e auxiliam no direcionamento dos programas de melhoramento genÃtico dessa cultura frente ao ataque de fungos. AlÃm de favorecerem o entendimento das interconexÃes bioquÃmicas e fisiolÃgicas que decorrem da interaÃÃo incompatÃvel planta-fungo. / Cowpea [Vigna unguiculata (L.) Walp.] belongs to the family Fabaceae and is widely used in food as a source of protein, carbohydrates, vitamins and minerals. Among the main features of cowpea, its high protein content and good tolerance to conditions of low water availability in soils, high temperatures and relative tolerance to salinity conditions typical of semi-arid regions of northeastern Brazil, are some of which can be cited. However, despite the considerable capacity of tolerance to different stress conditions, the productivity of cowpea is threatened by the action of various pathogens, among which stand out as major causes of fungal diseases of this crop, the example of Anthracnose as a result of infection by C. gloeosporioides, characterized by reddish-brown spots on the leaf veins that can be extended by all organs of the host plant. Fortunately, the cowpea has cultivars that have different characteristics of resistance against C. gloeosporioides, regarding the activation of plant defenses in incompatible interactions said, given that the pathogen is unable to resolve the infection. From this premise, it is worth mentioning that most of the mechanisms of plant resistance to pathogens is related to the differential gene expression of proteins that act as markers of defense in response to infection. Thus, this study proposes a differential proteomic analysis of the incompatible interaction (resistance) between plants of cowpea genotype BR3, and isolated LPVD-1, the fungus C. gloeosporioides in order to identify potential protein markers for the determinants of this resistance pathossystem. By using the approach 2D-PAGE in addition with mass spectrometry ESI-Q-TOF MS / MS, we have identified 118 differentially expressed proteins, whereas proteins overexpressed (102) and down-expressed (16), involved in various cellular processes, such as : energy metabolism, photosynthesis, protein and nucleic acids metabolism, stress response, cellular transport, redox homeostasis, signaling and defense, with emphasis on expression of PR-10 proteins (pathogenesis-related), remorina and ascorbate peroxidase that had significant alterations at all time points tested. These findings demonstrate the complexity of the mechanisms involved in plant resistance and assist in directing the programs of genetic improvement of this crop against fungal attack. Furthermore, itâs promoting the understanding of the biochemical and physiological interconnections arising from incompatible plant-fungus interaction.
86

Cloning, sequencing and molecular modeling by homology of a partial sequence of genotypes vicilin - of -string [Vigna unguiculata (L.) Walp.] In relation to the contrasting resistance weevil Callosobruchus maculatus / Clonagem, sequenciamento e modelagem molecular por homologia da sequÃncia parcial de uma vicilina de genÃtipos de feijÃo-de-corda [Vigna unguiculata (L.) Walp.] contrastantes em relaÃÃo à resistÃncia ao caruncho Callosobruchus maculatus

Bruno Henrique Maia Silva 28 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The cowpea bean [Vigna unguiculata (L.) Walp.] is a legume with high protein levels, largely cultivated and consumed in the Northeast of Brazil. Due to your economic importance, there are several studies that search resistant forms of cultivars of this kind of bean, as they is often attacked by different kinds of pests and predators. One of the most common is the weevil Callosobruchus maculatos. With the discovery of resistant cultivars for this insect many questions emerged about what biological component of the plant was responsible for such defensive action. Some studies suggest that this resistance is due to vicilin, which are reserve nutritious proteins, present in the seeds of cowpea. In this work, regions belonging to the vicilin gene of two contrasting cultivars in relation to resistence to weevil were sequenced, one resistant (IT81D-1053) and a susceptible (EPACE-10). These sequences, which come from several clones, were analyzed and thereby deducting its three-dimensional structure was made through a homology modeling using as template one 7S globulin from adzuki bean (Vigna angularis) identified as 2EA7 in the PDB database. Sequence analysis revealed that there are two regions highly variable in sequence from the vicilin gene, and these regions are rich in glutamine. Previous studies suggest that resistance to weevil occurs in the fact that the vicilin can bind to chitin and such glutamine rich regions are potentially chitin binding due to the high ability to form hydrogen bonds between the residues of glutamine and residues of N-acetylglucosamine. The structural analysis also supports this assumption, because the region rich in glutamine is very exposed, in relation to the protein surface, which facilitates the interaction of these amino acid residues with chitin. However more refined studies are needed to have a certainty of how is this interaction between vicilin and chitin, and if these same proteins are in fact fundamental in the resistance against the weevil. / O feijÃo-de-corda [Vigna unguiculata (L.) Walp.] à uma leguminosa com alto teor de proteÃnas, muito consumida e cultivada na regiÃo Nordeste do Brasil. Devido a sua importÃncia econÃmica, existem vÃrios estudos que procuram formas de cultivares resistentes desta espÃcie de feijÃo, pois esta à muito atacada por diversos tipos de pragas e predadores. Um dos mais comuns à o caruncho Callosobruchus maculatos. Com a descoberta de cultivares resistentes a este inseto, questionou-se sobre o componente biolÃgico da planta responsÃvel por tal aÃÃo defensiva. Alguns estudos sugerem que essa resistÃncia ocorre devido as vicilinas, que sÃo proteÃnas de reserva nutritiva, presentes nas sementes do feijÃo-de-corda. No presente trabalho, foram sequenciadas regiÃes pertencentes ao gene de vicilina de dois cultivares contrastantes em relaÃÃo ao ataque do caruncho, sendo um resistente (IT81D-1053) e outro suscetÃvel (EPACE-10). Essas sequÃncias, advindas de vÃrios clones, foram analisadas e com isso foi feita a deduÃÃo de sua estrutura tridimensional atravÃs de uma modelagem por homologia, utilizando como molde uma globulina 7S de feijÃo-azuki (Vigna angularis) identificada como 2EA7 no banco de dados PDB. A anÃlise das sequÃncias revelou que hà duas regiÃes bastante variÃveis na sequÃncia do gene da vicilina, sendo essas regiÃes ricas em glutamina. Estudos anteriores sugerem que a resistÃncia ao gorgulho se dà no fato de que as vicilinas conseguem se ligar a quitina, e tais regiÃes sÃo potencialmente ligantes a quitina devido a grande capacidade de formar ligaÃÃes de hidrogÃnio entre os resÃduos de glutamina e os resÃduos de N-acetilglucosamina. A anÃlise estrutural tambÃm corrobora esta hipÃtese, pois a regiÃo rica em glutamina à bastante exposta, em relaÃÃo à superfÃcie proteica, o que facilita a interaÃÃo destes resÃduos de aminoÃcidos interagirem com a quitina. Entretanto estudos mais refinados sÃo necessÃrios para se ter uma maior certeza de como se dà esta interaÃÃo entre vicilinas e a quitina, e se de fato essas proteÃnas sÃo mesmo fundamentais na resistÃncia contra o caruncho.
87

Growth and yield responses of maize (Zea mays L.) and cowpea (Vigna unguiculata L.) in an intercropping system

Thobatsi, Jacob Thobatsi 12 October 2009 (has links)
Maize is the third most important cereal crop in the world and many subsistence farmers are practicing intercropping of it with legumes due to land scarcity and in order to enhance production. Intercropping system is being practiced in may areas of South Africa mainly in the Limpopo province. The objective of the study was to evaluate the crop responses to intercropping maize with different growth length cowpea cultivars. The effects of intercropping on weed growth, maize and cowpea growth and yield components were investigated. The experiment was conducted during the 2005/06 and 2006/07 seasons at Bethlehem and Potchefstroom. Treatments were: maize sole, maize+PAN311 (short duration cowpea cultivar), maize+Glenda (medium duration cowpea cultivar), maize+Agrinawa (long duration cowpea cultivar) and sole plots of all cowpea varieties. Each plot was divided into two weed levels where all the plots were kept weed free for one month after planting, after which one half was left weedy and the other half weed free. Weed sampling was done within each weed treatment. Intercropping reduced maize LAI and plant height while time to physiological maturity was also reduced by weed infestation, especially under drier and warmer environments. Glenda and Agrinawa intercrops produced more nodules per plant under cooler and wetter conditions. Agrinawa produced the highest leaf and total DMY under sole crop conditions and this was significantly reduced by weed infestation. Different growth duration cultivars did not differ in their N2-binding abilities. Maize intercropping, especially with Glenda and Agrinawa, significantly reduced weed biomass. Maize sole crop under zero weeds had high grain yield compared to intercropping. PAN311 and Glenda sole crops under zero weeds produced higher yields under dry and warmer conditions, and cooler and wetter conditions, respectively, compared to intercropping. High cowpea grain yields were strongly correlated to more seeds per pod and larger pod lengths and number of pods per plant especially for Glenda. No intercropping advantage compared to sole cropping was observed (total LER < 1). This implies that maize and cowpeas must rather be planted as sole crops for better yields under wetter and cooler, and warmer and drier conditions. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Plant Production and Soil Science / unrestricted
88

A new disease of cowpea caused by Alternaria cassiae

Van den Berg, Noelani 26 May 2006 (has links)
Cowpea (Vigna unguiculata (L.) Walp is an indigenous food legume in Africa, which has great production potential, especially in areas with low agricultural resources. During surveys of cowpea fields in southern Africa, a new foliar disease was recorded. Alternaria cassiae Juriar&Khan was consistently isolated from diseased plant material. Pathogenicity was confirmed using Koch's Postulates. The effect of different culture media, temperature, light and wounding on the growth and sporulation of the fungus was studied. A. cassiae grew well and produced conidia abundantly when maintained on V8-agar at 25°C in a 12h UV-light/12h dark cycle. Sporulation was further enhanced by wounding the cultures. The pre-penetration and infection process of A. cassiae on cowpea leaves was studied by light and scanning electron microscopy. Conidia germinated within 2-3h post inoculation (hpi), forming multiple germ-tubes randomly that grew in any direction across the leaf surface. By 8hpi terminal or intercalary appressoria were formed above epidermal cells or over stomata. Occasionally germ-tubes entered stomata, without the formation of appressoria. Penetration of the plant surface, whether directly through the epidermis or indirectly through stomata was observed 72hpi. Following penetration bulbous primary hyphae were observed within the sub-stomatal cavities, secondary hyphae developed from the primary hyphae and grew within the intercellular spaces penetrating epidermis and mesophyll cells. A. cassiae is a necrotrophic fungus as the infection process is characterised by a destructive necrotrophic phase where plant cells became necrotic even prior to fungal penetration. Conidial morphology, types and development of the fungus were studied in vitro on different culture media and in vivo on cowpea leaves. A. cassiae produced a mixed population of three conidial types. Conidia were formed singly or in chains of 2-4 conidia. Conidia with long, filiform beaks and conidia with shorter beaks, converted into secondary conidiophores were more frequently produced than mature, beakless conidia on all the media, except on potato dextrose agar. Conidial body and beak sizes were variable when measured in culture and on cowpea leaves. Conidia produced in culture were larger, than those produced in vivo. Conidiophores emerged directly through the epidermis or stomata or were formed when hyphae growing on the leaf surface differentiated into conidiophores. Smooth, bud-like conidial initials were produced at the apex of conidiophores. Conidia matured and became elliptical to obvate and densely verrucose. Once a mature conidium had detached, a small pore was visible at the apex of the conidiophore. A. cassiae was shown to be seed-borne in cowpea. Six fungicides i.e. Benomyl, bitertanol, captab, mancozeb, propiconazole and triforine were evaluated for their efficacy in reducing mycelial growth of A. cassiae in vitro. All fungicides except benomyl proved to be effective. Cowpea seeds were artificially inoculated with A. cassiae and treated with all the fungicides except benomyl. Percentage germination and infection was determined in vitro. Percentage emergence, disease incidence, root and shoot lengths and abnormalities were determined in greenhouse trials. Only bitertanol at l.5x the recommended dosage significantly reduced percentage germination. All treatments except triforine l.0x and l.5x significantly decreased the percentage infection of artificially inoculated seeds. None of the treatments except bitertanol l.5x showed a difference in shoot and root length when compared to the control. Captab l.5x the recommended rate proved to be the best treatment over all. / Dissertation (MSc (Botany))--University of Pretoria, 2006. / Plant Science / unrestricted
89

Improving dryland maize (Zea mays) productivity through crop rotation with cowpeas (Vigna unguiculata)

Medupe, Mercy Lebogang 11 August 2010 (has links)
Maize is the most important cereal crop grown in areas of South Africa by both small-scale and commercial farmers. Maize monocropping without sufficient input and declining soil nitrogen content are some of the factors that limit yield. The objective of the study was to evaluate the effect of different cowpea cultivars and populations on growth, yield and yield components of succeeding maize. The effects of cropping systems on soil N content were also observed. Field experiments were conducted during the 2005/2006 and 2006/2007 growing seasons at Potchefstroom and Taung in North West province. The trial consisted of four cowpea cultivars: PAN 311 (short duration cowpea cultivar), CH 84, Bechuana white (medium duration cowpea cultivar) and TVU 1124 (long duration cowpea cultivar) and, four planting densities (10 000, 15 000, 20 000 and 40 000 plants ha-1). Maize was used as sequential test crop to determine the residual effect of previous cowpea treatments. Cowpea grain yield increased as planting density increased at both localities. TVU 1124 gave highest grain yield of all cowpea cultivars at both localities. Total dry matter yield also increased with increasing planting density. After cowpea soil NO3- and NH4+ content increased with increasing density. Similarly, soil NO3- content of maize following cowpea showed a considerable improvement, compared to maize monocropping. The highest soil NO3- and NH4+ content was observed when maize followed Bechuana White. Significant differences were also observed in soil microbial activities among the cultivars. Maize grain yields and plant height responded positively to the previous cowpea crop, compared with maize monocropping at both locations, but especially at Taung. Maize stover yield, cob length and KNC significantly responded to maize and cowpea rotation compared to maize monocropping at Taung. These results further confirm the potential of using cowpea to contribute soil N to subsequent maize crops in a rotational system. Copyright / Dissertation (MScAgric)--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted
90

Assessment of co-inoculation of Bradyrhizobium Japonicum and Bacillus subtilis on yield and metabolic profile of Bambara groundnut and cowpea under glasshouse conditions

Nelwamondo, Aluwani Mutanwa 01 1900 (has links)
Text in English with abstracts in isiVenda and Sepedi / Bambara groundnut and cowpea are essential legumes that are well adapted to unfavourable environmental conditions and have high dietary values for humans. However, they are under-researched and under-utilised. Thus, there are limited records on yields and metabolic profiling of these leguminous crops co-inoculated with B. japonicum and Bacillus subtilis. Generally, very few studies have reported on the effects of co-inoculation of other plant growth-promoting rhizobacteria and rhizobia strains on leguminous plants. This study therefore assessed the effects of B. subtilis (strain BD233) on germination of Bambara groundnut under different temperature regimes, and evaluated the effects of co-inoculation of B. japonicum and B. subtilis on yields of cowpea under glasshouse conditions. The study also assessed the metabolite profile of the crops using 1H nuclear magnetic resonance (NMR) spectroscopy. The data showed that inoculation of Bacillus subtilis on Bambara groundnut landraces under different temperatures enhanced germination (germination percentage, germination rate indices and plumule length). Furthermore, co-inoculation with B. japonicum and Bacillus subtilis (strain BD233) improved plant yield of cowpea plants. Partial least squares-discriminant analysis (PLS-DA) revealed distinct separations between treatments (co-inoculation of B. japonicum and Bacillus subtilis, inoculation of B. japonicum, uninoculated plus NO3 and zero inoculation) on Bambara groundnut and cowpea plants. The VIP score revealed that co-inoculation with B. japonicum and Bacillus subtilis (strain BD233) resulted in low concentrations of metabolites in Bambara groundnut plants and in contrast, high concentrations of metabolites in cowpea plants. Co-inoculation with B. japonicum and Bacillus subtilis (strain BD233) has a potential of improving yield of both Bambara groundnut and cowpea in sustainable agriculture. The metabolic profile of Bambara groundnut and cowpea subjected to co-inoculation has shown that both crops metabolic composition and profile are highly dependent on co-inoculation. / Phonda na ṋawa ndi mangaṋawa a ndeme ane a kona u tea zwavhuḓi kha nyimele dza vhupo vhune ha si vhe havhuḓi na ndeme ya nṱha ya pfushi kha vhathu. Naho zwo ralo, a hu athu u itwa ṱhoḓisiso dzo linganaho nga hadzo na u sa shumiswa Nga zwenezwo hu na rekhodo dzo pimiwaho nga ha khaṋo na u ela tshileme tsha molekulu ṱhukhu dza methaboḽiki dza zwiliṅwa izwi zwa mangaṋawa u khetha na B. japonicum na Bacillus subtilis. Nga u angaredza, ndi ngudo dzi si nngana dzo no vhigwaho nga ha masiandaitwa a khetha nyaluwo ya zwimela zwine zwa ṱuṱuwedza bakitheria dzine dza baḓekanywa na midzi na bakitheria dzine dza shandukisa naiṱirodzheni u vha amonia kha zwimela zwa mangaṋawa. Ngudo heyi nga zwenezwo yo asesa masiandaitwa a B. subtilis (tshiliṅwa tsha BD233) kha mumelo wa phonda nga fhasi ha ndaulo ya thempheretsha dzo fhambanaho, na u ela masiandaitwa a u khetha B. japonicum na B. subtilis kha khaṋo dza phonda na ṋawa nga fhasi ha nyimele ya fhethu hune ha ṱavhiwa zwimela nga fhasi ha tsireledzo kana ndangulo. Ngudo dzo dovha dza ela tshileme tsha molekulu ṱhukhu dza methaboḽiki dza zwiliṅwa hu tshi shumiswa 1H maanḓa a u tzwonzwiwa ha nyukiḽia nga eḽekiṱhironiki maginethe (NMR) nga u ṱanganelana ha radiesheni ya eḽekiṱhironiki maginethe. Data yo sumbedza u ḓivhadzwa ha Bacillus subtilis kha tshiliṅwa tshapo tsha phonda fhasi ha thempheretsha dzo fhambanaho u khwinisa mumelo (phesenthedzhi ya mumelo, zwisumbi zwa phimo ya muelo na vhulapfu ha pulumule). U isa phanḓa, u ḓivhadzwa hafhu ha B. japonicum na Bacillus subtilis (tshiliṅwa tsha BD233) khaṋo yo khwiniswaho ya tshiliṅwa kha zwimela zwa ṋawa. Musaukanyo wa u khethekanya zwitatisiṱika (Partial least squares-discriminant analysis) (PLS-DA) wo sumbedza khethekanyo dzo fhambanaho vhukati ha kushumisele (u ḓivhadzwa hafhu ha B.japonicum na Bacillus subtilis, u ḓivhadzwa ha B. japonicum, i songo ḓivhadzwaho hafhu na NO3 na ziro i songo ḓivhadzwa hafhu) kha phonda na zwiliṅwa zwa ṋawa. Tshikoro tsha VIP tsho wanulusa uri u ḓivhadzwa hafhu ha B. japonicum na Bacillus subtilis (kha tshiliṅwa tsha BD233) zwo bveledza mutzwonzwo wa fhasi wa methobolaithisi kha zwiliṅwa zwa phonda na phambano, ya mutzwonzwo wa nṱha wa methobolaithisi kha zwiliṅwa zwa ṋawa. U khetha ha B. japonicum na Bacillus subtilis (kha tshiliṅwa tsha BD233) zwo vha na ndeme ya u khwinisa khaṋo ya vhuvhili hazwo phonda na ṋawa kha vhulimi vhu sa nyeṱhi. U ela tshileme tsha molekulu ṱhukhu dza methaboḽiki dza phonda na ṋawa tenda u ḓivhadzwa hafhu ho sumbedza uri vhuvhili ha kubveledzele kwa methaboḽiki ya zwiliṅwa na muelo zwo ḓitika nga maanḓa nga u khetha. / Ditloo tša Bambara ke dipeu tše bohlokwa tšeo di kgonago go phela gabotse go maemo a tikologo yeo e sego ya loka e bile di na le boleng bja godimo bja dijo tšeo di lekanego go batho. Le ge go le bjalo, gona le dinyakišišo tša fase ka tšona le gore ga di šomišwe kudu. Ka gona, go na le direkhoto tše dinnyane ka ga pego ya mehola le tšhomišo ya yona ka ga dibjalo tše tša go dira dipeu tšeo di kopantšhwago le B. japonicum le Bacillus subtilis. Ka kakaretšo, dinyakišišo tše dinnyane kudu di begile ka ga dikhuetšo tša kopantšho ya mehlare e mengwe ya go huetša go gola ga pakteria ya medu (rhizobacteria) le dingangego tša pakteria ya ka gare ga medu (rhizobia) go dibjalo tša dipeu. Nyakišišo ye ka gona e lekotše dikhuetšo tša B. subtilis (strain BD233) go melo ya ditloo tša Bambara ka fase ga maemo a dithempereitšha tša go fapana, le go lekola dikhuetšo tša kopantšho ya B. japonicum le B. subtilis go mehola ya ditloo tša Bambara le dinawa ka fase ga maemo a ntlo ya digalase. Nyakišišo gape e lekotše pego ya tšhomišo ya dibjalo go šomišwa sedirišwa sa go laetša maatlakgogedi sa 1H (NMR). Tshedimošo e bontšhitše gore tsenyo ya Bacillus subtilis go ditloo tša Bambara tša tlwaelo ka fase ga dithempereitšha tša go fapana go kaonafaditše go mela (phesente ya go mela, lebelo la dikelo tša melo le botelele bja kutu ya sebjalo). Gape, kopantšho le B. japonicum le Bacillus subtilis (strain BD233) go kaonafaditše mehola ya dibjalo tša mehlare ya dinawa. Tshekatsheko ya go hwetša tswalano ya dithišu tše pedi (PLS-DS) e utollotše ditlogelano tša go fapana magareng ga mekgwa (kopantšho ya B. japonicum le Bacillus subtilis, tsenyo ya B. japonicum, yeo e sego ya tsenywa le NO3 le tsenyo ya lefeela) go ditloo tša Bambara le dibjalo tša dinawa. Dipoelo tša VIP di utollotše gore kopantšho ya B. japonicum le Bacillus subtilis (strain BD233) e tlišitše dipoelo tša fase tša ditšweletšwa tša dimolekule tša dibjalo tša ditloo tša Bambara e bile gape ge re dira phapanyo, bontšhi bjo bo lego godimo bja ditšweletšwa tša dimolekule ka go dibjalo tša dinawa. Kopantšho ya B. japonicum le Bacillus subtilis (strain BD233) e na le kgonagalo ya go kaonafatša mehola ya bobedi ditloo tša Bambara le dinawa ka go temo ya sa ruri. Seemo sa ditšweletšwa tša ditloo tša Bambara le dinawa tšeo di dirilwe kopantšho se bontšhitše gore bobedi tlhamotšweletšo le seemo sa dibjalo tše di ithekgile kudu mo go kopantšho. / Agriculture and  Animal Health / M. Sc. (Agriculture)

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