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Accumulation and recovery of nitrogen in mixed farming systems using legumes and other fertility building cropsDoel, J. M. January 2012 (has links)
Fertility-building crops (FBCs) offer the opportunity to alleviate the costs of inorganic fertiliser by providing an alternative supply of available nitrogen (N) in soils. A survey of relevant literature reviewed the types of FBCs, their nitrogen accumulation potentials, residue characteristics, and subsequent release patterns. It also identified a paucity of data concerning the response of different species to UK climatic, soil, and management conditions. In order to investigate these relationships further pot and field trials were established in 2007 at the Royal Agricultural College, Cirencester (SP 00481 01382) and at Coates Manor Farm (SO 98473 00402) on Sherborne series (typical Cotswold) soils, to investigate the biology and morphology of FBCs potentially suitable for short term fertility-building, their accumulation of N under field conditions, and its subsequent recovery within test crops. Data so obtained was used as a verification and refinement tool for the FBC model (Cuttle et al, 2003), a simple, commercially applicable, rotation-based model which can be applied to both organic and conventional production systems. Nine leguminous and two non-leguminous FBC treatments were established in April 2007 by straight sowing, followed by mulching at the conclusion of the nitrogen accumulation phase and by undersowing in spring barley (Hordeum sativum). The recovery test crops (winter and spring wheat Triticum aestivum L.) were established in September 2007 and March 2008. All FBCs established successfully. Above-ground dry matter (DM) yield and residue quality (C:N ratio) of FBCs varied significantly (P<0.05) between crops and cropping regimes with a significant correlation (r2=0.418) between DM yields and C:N ratios. FBCs and cropping regimes had significant effects (P<0.001 and P<0.05 respectively) on potential mineralisable nitrogen (PMN) levels in the soil and on the grain yields of winter and spring wheat test crops. Straight sown Lupinus albus, Trifolium pratense, Trifolium repens and a legume mixture resulted in higher winter wheat grain yields. However, the opportunity cost associated with straight sowing (i.e. the gross margin foregone from a spring barley crop) meant that the rotation would probably not be viable economically. Undersown Medicago lupulina, Vicia villosa, T. pratense, T. repens and the legume mixture gave worthwhile yield increases in spring wheat without incurring a yield penalty in the spring barley cover crop. Following enhancement and using actual data from the trials, the FBC model (Cuttle et al, 2003) provided encouraging predictions (R>0.6) for soil mineral nitrogen (SMN) and key parameters were identified for future use. It was concluded that FBCs established for short term soil fertility building could provide a worthwhile enhancement of soil N levels and grain yields in a conventional arable rotation, particularly in spring wheat following FBCs undersown in spring barley. It was also concluded that the FBC model (Cuttle et al, 2003), following further enhancement, and using additional data from these and other similar trials, could provide reasonably accurate estimates of SMN to aid more precise applications of N fertiliser in the future.
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Evaluation of selected legumes for sustainable weed ecology/soil fertility/livestock management interactions in crop-livestock systems of the moist savannah of NigeriaOwoeye, Lawrence Gbadebo 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This project aimed at enhancing the net benefit in production systems. It took
a holistic approach to evaluate the potential interactions of herbaceous
legumes in relation to weed dynamics, soil fertility and livestock management
in the crop-livestock system in Nigeria. The project was carried out between
2000 and 2002 in two localities. These were the National Animal Production
Research Institute (NAPRI) at Zaria in the northern Guinea savannah and the
International Institute of Tropical Agriculture (IITA) at Ibadan in the derived
savannah. The main experiment was carried out in the northern Guinea
savannah, while the secondary experiments were simultaneously conducted
in the derived savannah and the northern Guinea savannah. The
experimental design for the three experiments reported in this thesis is a splitsplit
plot, fitted into randomised complete block design (RCBD), with four
replications. Main plot treatments were herbaceous legumes, namely Vigna
unguiculata, Arachis hypogaea, Glycine max, Aeschynomene bistrix,
Centrosema pascuorum, Stylosanthes guianensis and natural vegetation.
Sub-plot treatments were management systems (1) M1, 'residues left in the
field'; (2) M2, 'residues taken out of the field' and (3) M3, 'residues fed to
livestock, manure/urine/refused feeds returned'. Sub-plot treatments were
administered in a sequence following rotational fallows of herbaceous
legumes and natural vegetation. However, plots in the secondary
experiments were not subdivided before the cropping of maize in 2002, and
for logistical reasons only two sub-plot treatments, M1and M2, are featured in
this experiment. Herbaceous legumes were established at the start of the rainy season,
approximately in June, in 2000, 2001 and 2002. All herbaceous legumes
received single super phosphate (SSP) at 20kg ha" P20S at planting, while
minimum hand weeding was done to maintain pure legume stands during the
establishment phase. Forage biomass was higher in the derived savannah
than in the northern Guinea savannah. Similarly, higher forage yields were
observed after two consecutive years of legume fallow and natural vegetation,
compared to the first year plots. Grain yield for Glycine max was consistently
higher than for the other two grain legumes in 2001 and 2002.
Chemical analysis of herbaceous legumes and natural vegetation showed that
crude protein values ranged between 11.2% to 17.3% for legumes; that was
significantly (p<0.05) higher than the 8.6% value found for natural vegetation.
Moreover, all herbaceous legumes and natural vegetation, except Arachis
hypogaea, had dry matter digestibility values of more than 30%.
Maize grain and stover yields on herbaceous legumes fallowed plots were
evaluated and compared with those for natural vegetation. Results in 2001,
i.e. after a one-year fallow with legumes, indicated that the dry matter of
maize grain and stover yields in the Stylosanthes guianensis plots were
higher among the forage legumes. Arachis hypogaea gave the highest grain
and stover yields among the grain legumes in the northern Guinea savannah.
Results in 2002, i.e. after a two-year fallow, also showed that the productivity
of maize planted on Arachis hypogaea and Glycine max fallowed plots were
consistently higher across the three management systems tested in the Centrosema pascuorum, Glycine max, Aeschynomene histrix, Vigna
unguiculata and least weight gain was recorded for the natural vegetation.
Objective functions in linear optimisation, or linear combinations in algebra,
used to link dynamic processes in livestock production (Iiveweight gain) with
the dynamic processes in soils (soil nitrogen), weeds (weed biomass),
herbaceous legumes (legume biomass) and crop production (maize grain and
stover yields) under varying management systems took the form:
Management system 1, Y, = f (XI, Xz, x4); Yr= 0
Management system 2, Y, = f (x" x2); Yz = 0
Management system 3, Y, = f (XI, Xz, xl); Yz= f (XI, Xz, X4. x5)
Where
(1)
(2)
(3)
Y1 = Crop in kg; Y2 = Livestock weight gain in kg; X1= Weed in kg; X2 = Soil N
g kg-1; X3 = Livestock compost in kg; N= Herbaceous legumes in kg; X5 =
Maize stover in kg, for the three management systems considered in this
experiment.
Deductions from these equations showed that Aeschynomene histrix
performed better under M1, i.e. when legumes residues were left on the field.
Natural vegetation performed better than the herbaceous legumes under M2,
i.e. when legumes residues were exported out of the field. However, the
presence of manure in M3 enhanced soil fertility in the system and improved
the overall productivity across all the legumes and natural vegetation.
Overall rankings, conducted by pooling all components in the system,
indicated that Glycine max performed best among the legumes, followed by
Stylosanthes guianensis and Arachis hypogaea, which ranked second and viithird
respectively. In relation to the specific legume groups, Stylosanthes
guianensis performed better than the other two forage legumes, while Glycine
max also performed better than the other two grain legumes tested.
We can see from these on-station research results that there are indications
of positive opportunities for improving overall productivity and resources. This
can be done through integrating and complementing crop and livestock
production, to provide a sustainable intensification of agriculture. / AFRIKAANSE OPSOMMING: Die studie is uitgevoer om die potensiële wisselwerking van kruidagtige
peulplante met onkruiddinamika, grondvrugbaarheid en veebestuur te
evalueer. Die hoofeksperiment in die "Northern Guinea Savannah" is vanaf
2000 tot 2002 uitgevoer by die "National Animal Production Research
Institute" (NAPRI) in Zaria, Nigerië. Die twee sekondêre eksperimente is
gelyktydig in Zaria en by die "International Institute of Tropical Agriculture"
(liTA) naby Ibadan in die "Derived Savannah" uitgevoer.
Die eksperimentele ontwerp was 'n dubbel gesplete perseelontwerp gepas in
'n volledig ewekansige blokontwerp met vier herhalings. Die hoofkomponente
was die kruidagtige peulplante naamlik: Vigna unguiculata, Arachis hypogaea,
Glycine max, Aeschynomene histrix, Centrosema pascuorum, Stylosanthes
guianensis en natuurlike plantegroei. Die gekose peulplante is potensieel
aangepas vir uiteenlopende omgewings en word dikwels na verwys as "'n
mandjie van opsies". Subperseel behandelings was (1) peulplant gevestig en
gelaat op die land - M1; (2) peulplant gevestig, geoes en weggeneem uit die
land M2 en (3) peulplant gevestig, geoes, vir vee gevoer,
mis/urine/vermorste voer terug na die land - M3. Die dubbel gesplete perseel
behandelings is toegedien in 'n sekere volgorde nadat die peulplant
rusoes/braak toegepas is. In die eerste jaar is die kruidagtige peulplante
geplant op die hoofperseel van 25m by Sam. In die tweede jaar is die
hoofperseel verdeel in twee persele waar onderskeidelik peulplante en mielies
gevestig is terwyl daar in die derde jaar 'n verdere verdeling was wat gelei het tot
verskillende gewasrotasiestelsels, nl. Peulplant-peulplant-mielies,
peulplant-mielies-peulplant en peulplant-mielies-mielies.
Parameters wat insluit planthoogte, -wydte en persentasie grondbedekking
van die kruidagtige peulplante is tweeweekliks gemeet op vier 1M2 persele
wat ewekansig oor elke hoofperseel versprei is in beide gebiede waar die
studie uitgevoer is.
Resultate het getoon dat die kruidagtige peulplante wat getoets is potensiële
kandidate is vir insluitings in gewas/weiding rotasiesteiseis. Alhoewel
voerproduksie hoër was in die "derived savannah" as in die "northern Guinea
savannah", het die prestasie van die peulplante in die noordelike savannah
gevarieer met die gewasproduksiestelsels. Hoër opbrengste is gerealiseer na
twee opeenvolgende jare van oesrus met peulplante vergeleke met die eerste
jaar waar daar geen residuele effek van die peulplante was nie, en die laaste
jaar wat deur 'n mielie-oes voorafgegaan is. Biomassa opbrengste na twee
jaar van aanhoudende verbouiing was die hoogste vir S. guianensis en die
laagste vir A. hypogea. Ruproteien inhoud van die kruidagtige peulplante het
gewissel van 170 g kg-1 DM in A. hypogea tot 62.4 g kg-1 DM in A histrix.
Graanproduksie deur G. max was deurlopend hoër in 2001 en 2002 vergeleke
met die twee ander graanproduserende peulplante nl. V. unguiculata en A.
hypogea. Die voerproduksie in 2002 was heelwat hoër as die vorige jaar.
Rotasie effekte op mieliegraan en oesreste na peulplante is vergelyk oor die
dubbel gesplete persele (areas met verskillende oesruslengtes) om die ximplikasies
van hulle residuele effek op grondvrugbaarheid verbetering en
onkruid dinamika te bepaal.
Mielie-opbrengs na een jaar van rusoes toon hoër waardes op persele wat
onder kruidagtige peulplante was vergeleke met natuurlike plantegroei. Net
so was die opbrengs deurlopend hoër op persele waar daar graan peulplante
was as waar daar voer peulplante was. Oor die algemeen was die waardes
hoër vir G. max, gevolg deur A. hypogea, A. histrix, C. pascuorum, V.
unguiculata, S. guianensis en die laagste vir natuurlike plantegroei. In terme
van die bestuurstelsels, het persele wat kompos ontvang het (M3) beter as
die ander twee bestuurstelsels presteer (2.6 Mg ha" mieliegraan). Produksie
van mieliegraan en oesreste na twee opeenvolgende jare van mielieverbouing
was die hoogste na G. max (7.2 Mg ha" mieliegraan), gevolg deur die A.
histrix perseel en die laagste op S. guianensis persele. Algemene
waarnemings oor die twee subpersele wat met mielies beplant was in 2002
het getoon dat mielies beter presteer het op persele wat twee opeenvolgende
jare met peulplante beplant was.
Onkruidsamestelling en verspreiding is in beide die peulplante en natuurlike
plantegroei gemeet. Grond vir saadbankontledings is op diagonale transekte
in 0.5m by 0.5m kwadrate gemonster. Grondmonsters is ge-analiseer vir pH,
totale stikstof, organiese koolstof, fosfor, kalsium en magnesium. Hierdie
parameters is gebruik in 'n meervoudige regressie ontleding om hulle effek op
onkruidspesievoorkoms te bepaal. Onkruidgetalle in lande na In rusoes het In deurlopende hoër vlak van
besmetting getoon op die natuurlike plantegroei persele as op die peulplant
persele. Die prestasie in terme van onkruidonderdrukking was in dalende
volgorde: S. guianensis, C. pascuorum, V. ungucuilata, G. max, A. hypogaea
en A. histrix. Die onkruidsamestelling het verskilonder die verskillende
behandelings en dit het ook met tyd verander in dieselfde behandelings.
In Bykomende eksperiment met die peulplante is uitgevoer om hulle effek op
inname en groei van skape, asook die effek op kompos wat gemaak is van
vermorste materiaal en uitskeidings van die skape, te bepaal.
Droë materiaal verteerbaarheid was hoog vir S guianensis, G. max en A.
histrix terwyl die laagste syfer verkry is by A. hypogea (177.6 g kg-1 DM).
Ramme wat met kruidagtige peulplante gevoer is het beter presteer as die
wat met natuurlike plantegroei gevoer is. Ramme wat met A. hypogaea
gevoer is, het In gemiddelde daaglikse toename (GOT) getoon van 85.7 g
daq", gevolg deur S. guianensis, C. pascuorum, G. max, A. histrix, V.
unguiculata en laaste natuurlike plantegroei.
Bykomende ontledings was gemik daarop om objektiewe funksies af te lei
om dinamiese prosesse in vee (massatoename) met dinamiese prosesse in
grond (grond N), onkruid (onkruidmassa), kruidagtige peulplante
(peulplantmassa) en mielies (mieliegraan en oesreste massas) onder
verskillende bestuurstelsels te verbind. In In poging om objektiewe funksies xiivan
die verskillende komponente van die studie te bepaal, is die volgende
lineêre funksies vir die drie bestuurstelsels oorweeg nl.
Bestuurstelsel1. Yl = f (Xl, xz, x.); Yz= 0
Bestuurstelsel 2, Yl = f (Xl, Xz); Yz= 0
Bestuurstelsel3, Yl = f (Xl, X2, Xl); Yz= f (Xl. Xz. x.. les)
Waar
(1)
(2)
(3)
Y1 = Oesopbrengs in kg; Y2 = Daaglikse massatoename in kg; X1 =
Onkruidmassa in kg; X2 = Grond N in g kg-1
; X3 = Kompos in kg; X4 =
Kruidagtige peulplante in kg; X5 = Mieliereste in kg.
Onder bestuurstelsel 1, het A. histrix beter as die ander gewasse presteer,
terwyl natuurlike veld beter presteer het onder bestuurstelsel 2. Dit is 'n
aanduiding dat bestuurstelsel 2 nie volhoubaar is nie. Die derde
bestuurstelsel verteenwoordig volle integrasie van gewas en vee
produksiestelsels. Die teenwoordigheid van mis in die stelsel het
grondvrugbaarheid verbeter en algemene produktiwiteit verbeter.
Hierdie resultate dui aan dat daar geleenthede is om algemene produktiwiteit
te verbeter deur integrasie en komplementering van gewas- en
veeproduksiestelsels om volhoubare intensifikasie van landbou te bereik.
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The evaluation and management of different grasses and legumes as potential cover crops in the vineyards of South AfricaFourie, J.C. 03 1900 (has links)
Thesis (PhD(Agric) (Agronomy))--University of Stellenbosch, 2007 / A selection of species suitable for cover crop management in the different wine grape
regions is required to enable more producers to apply this environment friendly practice
in a sustainable manner as part of an integrated production strategy. The correct
management practice(s) to be applied to these species over both the short and long
term in a cooler and warmer wine grape region needed clarification.
The effect of seeding date on the dry matter production (DMP) and weed control efficacy
of seven grasses and sixteen legumes, as well as varieties of three of these species,
was determined during 1991 and 1992. The decomposition rate of the mulches was
determined. In the cooler climate of Stellenbosch (33o55'S, 18o52'E), the Medicago
species, subterranean clovers, pink Seradella and three Vicia species did not compete
effectively with the winter weeds if the weekly precipitation from mid-March to mid-May
(autumn) exceeded 18 mm. The two oat species, as well as rye and triticale produced
more than five t/ha of dry matter if the precipitation exceeded 18 mm per week. The
DMP of the above-mentioned species indicated that these species could be considered
for cover crop management in Lutzville (31o35'S, 18o52'E), if full surface irrigation of 18
mm per week could be applied for 10 weeks directly after sowing, followed by 18 mm
fortnightly. Seeding date had a significant effect on DMP in both regions. A highly
significant correlation (r = 0.85, p ≤ 0.0001) existed between the decomposition rate of
the mulches and the initial amount of dry matter present on the soil surface.
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Phosphorus cycling in organic systems2014 January 1900 (has links)
Soil phosphorus (P) is often unavailable in SK soils due to immobilization by microbial biomass and complexation with cations. The prohibition of synthetic fertilizer use in organic systems means farmers rely on crop rotation or approved inputs to supply P for crops. Legumes in crop rotation add P to soil through decomposition and deposition, and approved fertilizers such as bone meal (BM), rock phosphate (RP), and composted manure add P to soil through dissolution.
Arbuscular mycorrhizal fungi (AMF) improve crop access to soil P. The fungi colonize roots of host crops, allowing roots to reach immobile pockets of soil P. Colonization by AMF is usually decreased or delayed following partial fallow periods, non-host plants, and the addition of soluble P fertilizers.
This thesis consists of two studies. For the first, the effects of crop rotation were tested on AMF colonization and soil P dynamics. Colonization by AMF of mycorrhizal crops was examined following a non-mycorrhizal crop, a partial fallow period, and mycorrhizal crops. All crops were colonized evenly (63-70%) at flowering despite non-mycorrhizal and partial fallow periods, and the sequence most depleted in soil N (wheat-barley) had the lowest colonization in August (36%).
The second study evaluated soil P and plant N and P after applications of BM, hydroxyapatite (HAP), and sheep manure compost. Compost application increased plant P uptake compared to the control (1.26 vs. 0.71 mg pot-1), while applications of BM and HAP alone did not. Compost application did not affect AMF colonization of wheat (Triticum aestivum L.).
Overall this research highlights the importance of legumes and composted manure use in organic systems. Legume use in crop rotation simultaneously increased soil P deposition and may have preserved AMF communities despite fallow periods and non-host crops in rotation. Conditions normally affecting AMF colonization in conventional systems did not apply. The use of composted manure in the greenhouse study resulted in the greatest P uptake and concentrations in wheat. Thus the use of legumes and composted manure may increase P availability to crops directly and indirectly: directly through soil P deposition and perhaps indirectly through the preservation of AMF communities.
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Extractives from the amaryllidacea and the fabaceae.Koorbanally, Neil Anthony. January 1999 (has links)
This work is an account of investigations into the chemistry of one of the members of the Amaryllidacae family, Ammocharis coranica, and one of the members of the Fabaceae family, Sophora velutina.
Chapter one is an account of the extractives from the bulbs of Ammocharis coranica. In all, twelve compounds, eight alkaloids and four cycloartane compounds have been isolated of which one alkaloid and one cycloartane compound have not been described previously. Plants belonging to the Amaryllidacae family have been used by traditional healers, especially in Africa, to treat a range of illnesses and diseases. The alkaloids isolated from these plants have been shown to exhibit responses to muscle stimulant, antiviral, antifungal, antiyeast, antimalarial, cytotoxic and antitumoural activities. Ammocharis coranica is used by the Zulu tribe in South
Africa to treat any illness believed to be caused by witchcraft. Alkaloids from the three most common types among the isoquinoline group were found in this species. These are lycorine, 1-O-acetyllycorine, hippadine, acetylcaranine, and the novel 1-O-
acetyl-9-norpluviine from the lycorine type, 6-α-hydroxypowelline from the crinine type and hamayne and crinamine from the haemanthamine type. Cycloartane compounds have not been reported previously from the Amaryllidaceae family. All four cycloartane compounds had a common side chain, containing an olefinic methylene group at position 24, but differed in their substituents at positions 3 and 4. These compounds were found to be 24-methylenecycloartan-3β-ol, cycloeucalenol,
cycloeucalenone and the novel compound 4-methylenepollinastanone. Chapter two is an account of the extractives from the seeds of Sophora velutina. The seeds of other Sophora species have been used in traditional ceremonies by the
Indians of the Southwest United States and adjacent Mexico because of their hallucinogenic activity. The seeds of Sophora velutina subsp. zimbabweensis found in Zimbabwe are suspected to have historically been used by the natives for their hallucinogenic properties. These plants have been known to contain several
quinolizidine alkaloids, flavonoids and isoflavonoids. One alkaloid, N-methylcytisine and two isoflavones, pseudobaptigenin and calycosin, as well as the common phytosterol, β-sitosterol were isolated from the seeds of this species. N-methylcytisine is a common quinolizidine alkaloid, isolated previously from several Sophora species and pseudobaptigenin and calycosin are well known isoflavones, isolated previously from several species in the Fabaceae. / Thesis (M.Sc.)-University of Natal, Durban, 1999.
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Prevent the World's Doom, Consume a Healthy Legume : A Qualitative Study of Attitudes and Purchase Intentions of Health-Conscious ConsumersDa Silva Lernstål, Sara, Kiratsopoulos, Konstantin January 2017 (has links)
Background: Agricultural activities occupy a significant part of the world’s land area and the food systems are comprehensively reliant on fossil fuels, resulting in that the sector is responsible for a large percentage of the world’s greenhouse gas emissions. Changes are needed in order to meet the challenges of developing sustainable food systems. One change strategy would be to replace parts of animal proteins with greener plant substitutes. This thesis is part of a four-year transdisciplinary research project with the aim to, within four years, develop domestically produced products based on Swedish legumes. This paper will focus on exploring significant components affecting health-conscious consumers’ attitudes and purchase intentions regarding legumes-based products. By the thesis, valuable information and insights regarding legumes as a protein substitute will be gathered amongst the growing consumer group of health-conscious consumers. Purpose: The purpose of this study is to explore the attitudes regarding legumes, and underlying key components affecting health-conscious consumers purchase intentions towards legume-based products. Additionally, two research questions have been developed to reach valuable findings for this investigation.
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Global warming : carbon-nutrient interactions and warming effects on soil carbon dynamicsAsandei, Ancuta January 2014 (has links)
In order to predict how terrestrial ecosystems will respond to global change, there is growing recognition that we need to better understand linkages between plant and soil processes. Previously the factors and processes with potential to influence the terrestrial carbon (C) cycle have been investigated in isolation from each other. This study investigated the interactions of nutrient availability and warming in controlling the soil carbon dynamics, with regards to the fate of already sequestered carbon in soil, under conditions of increasing atmospheric temperatures. The project objectives were addressed by three independent experiments designed to explain specific components of the carbon-nutrient cycle interactions, and the findings brought together to describe the implications for future soil carbon storage. The main measurements collected throughout this project included soil carbon dioxide (CO2) fluxes, partitioned into autotrophic and heterotrophic components, net ecosystem exchange and respiration fluxes, and background soil moisture and temperature data, backed by gas, soil and biomass analyses. In the two field experiments, these measurements were taken from plots with or without any inorganic nutrient additions or in the presence or absence of legumes providing biological nitrogen addition to the ecosystem. In the laboratory, temperature and nutrient availability were manipulated within the ecosystem. The reduction in decomposition rates, without reduction of productivity as a result of inorganic nutrient additions, indicated the potential for increasing C storage. There was also evidence that nutrient availability controls the strength of the link between plant and soil processes in semi-natural grasslands. The yields, decomposition rates and soil C fluxes recorded in the presence and absence of legumes provided some evidence of N2 fixation, improving ecosystem productivity and soil properties while reducing soil C effluxes, in a managed grassland. In the laboratory, the warming of soils from lysimeters with and without plants, receiving or not receiving fertiliser, supported the findings from field experiments regarding the importance of the soil-plant link in controlling C fluxes. However, C stocks and δ13C analyses showed that over a year’s worth of warming and nutrient manipulations made little difference to the amount of C stored in the soil, indicating that edaphic factors have greater control over the response of C dynamics to increased temperatures.
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A taxonomic study of the genus Lessertia DC. (Fabaceae, Galegeae)11 September 2013 (has links)
M.Sc. (Botany) / The genus Lessertia DC. consists of 54 species of papilionoid legumes. The species have imparipinnate leaves, paired stipules, sub-capitate or elongate racemes and compressed or inflated legumes. The closest relative of the genus is Sutherlandia R. Br. ex W. T.Aiton, which differs in having a very large, bird-pollinated flower, a standard which is smaller than the keel, a long ovary stipe and a very large, much inflated legume. The last comprehensive revision of Lessertia was done by Harvey (1862), where 30 species were recognized. Harvey concluded that the species were difficult to define. This study was therefore initiated to evaluate characters of possible taxonomic value so that the circumscription and identification of species can be facilitated. More than 1000 specimens from different herbaria were examined to study morphological characters such as habit, indumentum, leaves and leaflets, flowers and flowering times, fruits, habitat and distribution of the species. Flowers of all the species were dissected and flower parts were drawn using camera lucida. Flower characters such as the length, width and vestiture of the petals were studied. For flavonoids and terpenoids, 17 species of Lessertia were sampled for a pilot study to compare chemical compounds between the species. The ethnobotanical literature was reviewed in order to compile a list of all the species of value in traditional medicine. Vegetative characters are often not species-specific but they can be used to distinguish between some closely related species, either as single characters or as combinations of characters. Further details can be seen in the keys presented in this study.
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Consumo de frutas, legumes e verduras: relação com os níveis sanguíneos de homocisteína entre adolescentes / Intake of fruits and vegetables: relationship with blood levels of homocysteine among adolescentsBigio, Roberta Schein 29 August 2011 (has links)
Introdução: Frutas, legumes e verduras (FLV) contêm vários nutrientes com efeitos favoráveis para a saúde humana. Dentre estes, o folato é um dos nutrientes chaves envolvido na manutenção da saúde, com um potencial papel na redução das concentrações plasmáticas de homocisteína (hcy), reconhecido marcador de doença cardiovascular. Objetivos: Investigar o consumo de FLV, segundo características sóciodemográficas, antropométricas e de estilo de vida e relacionar o consumo de FLV e de folato com os níveis sanguíneos de hcy em adolescentes. Métodos: Este estudo utilizou dados de adolescentes de ambos os sexos, faixa etária de 12 a 19 anos, obtidos no Inquérito de Saúde ISA - Capital, realizado periodicamente no Município de São Paulo. O consumo de FLV foi estimado no estudo realizado em 2003, cuja amostra foi de 812 participantes. Para avaliação das relações entre FLV, folato e hcy, foram utilizados dados coletados no segundo ISA-Capital, entre os anos de 2008-2010 com amostra de 183 adolescentes. O consumo de FLV e de equivalentes de folato dietético (DFE), bem como o consumo de folato natural e ácido fólico, foram estimados por um recordatório de 24h. A análise bioquímica das concentrações plasmáticas de hcy foi realizada pelo método de cromatografia líquida. O ponto de corte de hcy plasmática utilizado foi de <8 mol/L para indivíduos com menos de 15 anos e <12 mol/L para indivíduos entre 15 e 19 anos. A concentração média de hcy plasmática foi descrita de acordo com os tercis de consumo de FLV, segundo as características sócio-demográficas, antropométricas e de estilo de vida. Todas as análises estatísticas foram realizadas no STATA® versão 10.0 considerando o nível de significância 5 por cento . Resultados: No primeiro estudo (2003) 20 por cento dos adolescentes não consumiram FLV no dia relatado e 6,5 por cento apresentaram consumo adequado. Renda, escolaridade do chefe da família e tabagismo influenciaram este consumo. Já no segundo estudo (2008-2010), 56 por cento não consumiram FLV e somente 4,9 por cento atingiram as recomendações. A prevalência de hiperhomocisteinemia na população estudada foi de 9,2 por cento . Adolescentes de 12 a 15 anos apresentaram menores valores de hcy (6,9mol/L) em comparação com os de 16 a 19 anos (8,4mol/L). Não foram encontradas diferenças significativas nos níveis plasmáticos de hcy analisados por tercis de consumo de FLV segundo características sócio-demográficas, de estilo de vida e antropométricas. Os alimentos que mais contribuíram com o consumo de DFE foram: pães (38,4 por cento ), seguidos pelo feijão (11,7 por cento ) e massas (10,1 por cento ). Para folato natural os alimentos de maior contribuição foram: feijão (30,3 por cento ), FLV (14,9 por cento ) e pães (14,6 por cento ); e, para o ácido fólico, se destacaram pães (53,3 por cento ), massas (14,6) e biscoitos (9,8 por cento ). Conclusão: O consumo de FLV por adolescentes está muito abaixo das recomendações nas duas amostras estudadas e não influenciou as concentrações plasmáticas de hcy / Background: Fruits and vegetables (FV) contains multiple nutrients with beneficial effects for human health. Among these, folate is one of the key nutrients involved in maintaining health, with a potential role in reducing plasma concentrations of homocysteine (hcy), recognized marker of cardiovascular disease. Objectives: To investigate the FV intake, according to socio-demographic, anthropometric and lifestyle characteristics and to relate the FV and folate intake with blood levels of hcy in adolescents. Methods: This study used data from adolescents of both sexes, aged 12 to 19, enrolled in the Health Survey ISA - Capital, periodically held in São Paulo. The FV intake was estimated in the study conducted in 2003, comprising 812 participants. To assess the relationship between FV, folate and hcy, we used data collected in the ISA Capital, conducted between the years 2008-2010 with a sample of 183 adolescents. The FV intake and dietary folate equivalents (DFE), as well as natural folate and folic acid intake, were estimated by a 24-hour recall. Biochemical analysis of plasma hcy was performed by liquid chromatography. The cutoff point for plasma hcy was <8 mmol/L for individuals younger than 15 years and <12 mmol/L for individuals aged between 15 and 19 years. The average concentration of plasma hcy was described into tertiles of FV intake, according to the socio-demographic, anthropometric and lifestyle characteristics. All statistical analyzes were performed in STATA ® version 10.0 with 5 per cent of significance level. Results: In the first study (2003) 20 per cent of adolescents not consumed FV on day evaluated and only 6.5 per cent had adequate intake. Per capita household income, head of familys level and smoking habit influenced this consumption. In the second study (2008-2010), 56 per cent not consumed FV and only 4.9 per cent met the recommendations. The prevalence of hyperhomocysteinemia was 9.2 per cent . Adolescents aged 12 to 15 years had lower levels of hcy (6.9 mmol/L) compared with 16 to 19 years (8.4 mmol/L). No significant differences were found in plasma levels of hcy into tertiles of FV intake according to socio-demographic, lifestyle and anthropometric characteristics. Foods that most contributed to DFE intake were bread (38.4 per cent ), followed by beans (11.7 per cent ) and pasta (10.1 per cent ). For natural folate, the foods that most contributed were: beans (30.3 per cent ), FV (14.9 per cent ) and breads (14.6 per cent ), and for folic acid, breads (53.3 per cent ), pasta (14.6) and biscuits (9.8 per cent ). Conclusion: FV intake by adolescents is below the recommendations and not influenced plasma concentrations of hcy
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AVALIAÇÃO DA DIGESTIBILIDADE IN SITU DE DUAS ESPÉCIES DE LEGUMINOSAS UTILIZADAS EM RECUPERAÇÃO DE ÁREAS DEGRADADAS.Davantel, Marciliana Goreti 13 March 2015 (has links)
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Previous issue date: 2015-03-13 / The study aimed to evaluate and compare the chemical composition and digestibility
of dry matter bean Guandu (Cajanus cajan L.) and Calopogonio (Calopogonium
mucunoides Std.). To test the degradability through the in situ, we used the of nylon
bags with, incubated in a male adult bovine cannulated in the rumen . The samples
of 6.0 g of each legume species were incubated in the rumen of the animal at time
periods of 0 , 12, 24 , 48, 72 and 96 hours. Incubation was performed in order to
remove all the nylon bags at the same time, allowing thereby uniformly cleaning
tools. The experiment was conducted according to a randomized design and the data
submitted to Tukey test. It was determined the dry matter, mineral matter, neutral
detergent fiber, acid detergent fiber, crude protein and in situ degradability of the dry
matter. Effects were observed (P <0.05) of the species, being verified interaction of
this factor, it was observed that there were differences (P <0.05) for contents of
mineral matter (MM), neutral detergent fiber (NDF) acid detergent fiber (ADF) and
crude protein (CP), with no effect (P> 0.05) for dry matter content (DM). The DM
content of calopo samples was 49.39% and pigeon pea was 47.44%. The calopo
was higher than pigeon pea in MM and CP levels. There was a difference to the
percentage of total fiber, the lowest value of NDF for calopo. In the effective
degradability calopo showed higher rates than pigeon pea. In the experiment it was
found higher nutritional value compared to calopo pigeon pea and can be adopted in
cattle feed. / O trabalho teve como objetivo avaliar e comparar a composição bromatológica e a
digestibilidade da matéria seca do Feijão Guandu (Cajanus cajan L.) e do
Calopogônio (Calopogonium mucunoides Desv.). Para o ensaio da degradabilidade
através da técnica in situ, usou-se o método de sacos de náilon, com incubação em
um bovino macho adulto canulado no rúmen. Amostras de 6,0 g de cada uma das
espécies de leguminosas foram incubadas no rúmen do animal nos períodos 0, 12,
24, 48, 72 e 96 horas. A incubação foi realizada de forma a se retirar todos os sacos
de náilon ao mesmo tempo, permitindo, dessa forma, lavagem uniforme do material.
O experimento foi conduzido segundo o delineamento inteiramente casualizado e os
dados submetidos ao teste de Tukey. Determinaram-se os teores de matéria seca,
matéria mineral, fibra em detergente neutro, fibra em detergente ácido, proteína
bruta e a degradabilidade in situ da matéria seca. Foram observados efeitos
(P<0,05) da espécie, sendo verificada interação deste fator, observou-se que houve
diferença (P<0,05) para os teores de matéria mineral (MM), fibra em detergente
neutro (FDN), fibra em detergente ácido (FDA) e proteína bruta (PB), não havendo
efeito (P>0,05) para o teor de matéria seca (MS). O teor de MS das amostras de
calopogônio foi 49,39% e do feijão guandu foi de 47,44%. O calopogônio foi superior
ao feijão guandu nos teores de MM e PB. Houve diferença para o percentual de
fibras totais, sendo o menor valor de FDN para o calopogônio. Na degradabilidade
efetiva o calopogônio mostrou maiores taxas do que o feijão guandu. No
experimento foi verificado maior valor nutricional do calopogônio em comparação ao
feijão guandu, podendo ser adotado na alimentação de bovinos.
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