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Articles 3421 - 3450 of 9503

Full-Text Articles in Agricultural Science

Effect Of Nitrogen Fertilization Upon Spring Growth In Thinopyrum Poticum In Alkaline Soils. Argentina, R Fernandez Grecco, A Sciotti, A Mazzanti, H Echeverria Jun 2024

Effect Of Nitrogen Fertilization Upon Spring Growth In Thinopyrum Poticum In Alkaline Soils. Argentina, R Fernandez Grecco, A Sciotti, A Mazzanti, H Echeverria

IGC Proceedings (1977-2023)

Wheatgrass is a perennial forage grass adapted to low fertility alkaline soils in the Flooding pampa. It has an annual forage growth cycle characterised by a high spring-summer concentration and low values in winter. The objective of this study was to assess that it is possible to anticipate and increase forage growth and DM production of wheatgrass pastures applying nitrogen fertilization. The experiment was carried out at the Balcarce Experimental Station from 28/08/95 to 04/12/95. Using a completely randomized block design the effects of 6 levels of N: 0, 50, 100, 150, 200 and 250 kg Nha-1, added as NO3 …


Effect Of Nitrogen Fertilization Upon Winter Growth In Natural Pastures Of The South East Of Buenos Aires Province, Argentina, R C. Fernandez Grecco, A E. Mazzanti, H A. Echeverria Jun 2024

Effect Of Nitrogen Fertilization Upon Winter Growth In Natural Pastures Of The South East Of Buenos Aires Province, Argentina, R C. Fernandez Grecco, A E. Mazzanti, H A. Echeverria

IGC Proceedings (1977-2023)

The effect of winter nitrogen fertilization upon herbage accumulation during the winter-spring period on a natural pasture of the Flooding Pampa dominated by cool season annual (Lolium multiflorum) and perennial (Stipa neesiana) grasses was evaluated. The experiment was carried out from August to November in 1994 and 1995. Fertilization treatments were: 0, 50, 100, 150, 200 and 250 kgN ha- 1 (N0, N50, N100, N150, N200 and N250, respectively). The experimental plots were set out in three randomized blocks. In 1994, maximum forage accumulation was reached at N150, and no significant differences were found among N150, …


Effectivity Of Arbuscular Mycorrhizas In Sustainable Grassland Agriculture Following Conversion From Intensive Management, W R. Eason, J Scullion, E P. Scott Jun 2024

Effectivity Of Arbuscular Mycorrhizas In Sustainable Grassland Agriculture Following Conversion From Intensive Management, W R. Eason, J Scullion, E P. Scott

IGC Proceedings (1977-2023)

With increased interest in sustainable agriculture, attention has focused on the role of arbuscular mycorrhiza (AM) in the productivity of agricultural systems. AM spores were taken from grassland and grass-arable systems with either a history of high-input, conventional, or low-input, organic management, and used as a source of inoculum in host plants (Allium amelioprasum, Trifolium repens and Lolium perenne). Spores from organic management systems produced a greater yield response than those from conventional systems. Where various spore inoculum produced differences in host growth responses, it was observed that the infected root of these host plants also produced similar …


Buffelgrass Forage And Seed Production Responses To N And Fertilization, W R. Ocumpaugh, M A. Hussey, B L. Burson Jun 2024

Buffelgrass Forage And Seed Production Responses To N And Fertilization, W R. Ocumpaugh, M A. Hussey, B L. Burson

IGC Proceedings (1977-2023)

Forage and seed production responses to nitrogen (N) and phosphorus (P) fertilizer of Common buffelgrass (Cenchrus ciliaris L.) were evaluated for three years (1991-93). An incomplete factorial set of five rates of N and P were applied each year. Seed data were collected by hand stripping mature seed followed by a forage harvest. Seed quality characteristics were determined on each seed sample. No response to N fertilizer was observed in 1991 nor to P in any year. In 1992, there was a linear forage yield response to N fertilizer. In 1993, both the linear and quadratic effects of N …


Grassland Management In Central Area Of The Masurian Landscape Park, K Mlynarczyk, E Marks, E Korona Jun 2024

Grassland Management In Central Area Of The Masurian Landscape Park, K Mlynarczyk, E Marks, E Korona

IGC Proceedings (1977-2023)

Permanent grassland occupy some 12% of the area of the Masurian Landscape Park. The Cirsio-Polygonetum plant association was distinguished on the semi-natural meadows situated on the peat-marsh soil. Changes in botanical composition of the meadow sward and the productivity of DM, against a background of different mineral fertilization, were examined in a medium-scale plot experiment. It was concluded that both aspects ofutilization must be accorded high priority in the case of extensively managed meadows: medium level of forage production and the landscape conservation.


Reserving Pastures In Communal Grasslands By Agropastoralists Of Tanzania, M L. Kusekwa, A J. Mwilawa, J.K K. Msechu Jun 2024

Reserving Pastures In Communal Grasslands By Agropastoralists Of Tanzania, M L. Kusekwa, A J. Mwilawa, J.K K. Msechu

IGC Proceedings (1977-2023)

Studies were conducted in “Maasai” and “Gogo” tribal communities to gain understanding of traditional management of reserved pastures. Survey techniques were used and forage production and chemical composition were estimated. Household heads were invariably old men who had no formal education. Household size averaged 14 and 11, in Maasai and Gogo tribes respectively. Most reserved pastures were privately owned. Over 90% of pastoralists preferred individual ownership of reserved grazing. Herbage production was 2510 kg DM/ha in Maasai and 3680 kg DM/ha in Gogo locations. Pastures and low protein content (5.1-6.5% CP). Constraints to reserve grazing strategies were land and water …


Impact Of Extensive Management On Demography Of One Invasive Species Of Permanent Grasslands, D Magda Jun 2024

Impact Of Extensive Management On Demography Of One Invasive Species Of Permanent Grasslands, D Magda

IGC Proceedings (1977-2023)

The objective of this study is to show the effect of extensive practices on the population dynamics of a grassland species (Chaerophyllum aureum) in order to control invasion process. Fertilisation intensity (none or 45g/m2), number (none, one or two) and date of cutting (before or after seed maturity) have been experienced on permanent plots in fields to follow consequences on demography of adults and seedlings. Adult density is regulated through cutting effect and intraspecific competition process. Reduction of competition by cutting leads to a paradoxal highest adult survival rate in on cut treatment compared with abandoned invaded fields. …


Influence Of Drying Method And Temperature On Ruminal Degradable Protein Of Switchgrass, D E. Farnham, K J. Moore, J R. George Jun 2024

Influence Of Drying Method And Temperature On Ruminal Degradable Protein Of Switchgrass, D E. Farnham, K J. Moore, J R. George

IGC Proceedings (1977-2023)

The nutritional value of herbage protein fed to ruminant livestock can be influenced greatly by the extent to which it is degraded in the rumen. This study was conducted to determine if drying method and temperature alters measurements of in situ ruminal escape protein (EP) of switchgrass herbage. Switchgrass harvested at the pre-heading stage was either air dried, freeze dried, or oven dried at 38, 49, 60, or 710 C. Samples from each of the six drying treatments were digested in situ in Dacron bags for 4, 8, 12, or 16 h. Drying treatment had a significant impact on EP …


Development Of Natural Horse Pastures In Finland In The 1900s, H Jansson, K H. Jansson, A Olin, T Talikka, J Pykala Jun 2024

Development Of Natural Horse Pastures In Finland In The 1900s, H Jansson, K H. Jansson, A Olin, T Talikka, J Pykala

IGC Proceedings (1977-2023)

The purpose of the study was to assess the importance of natural pastures as a growing environment for horses and, at the same time, to evaluate the landscape value of such pastures. Another aim was to look at possible ways of conserving areas which have been in use as horse pastures for a long period of time as traditional biotopes belonging to the Finnish horse grazing culture, and to examine how their management and care could be improved.


Relationship Of Soil To Native Pasture In A Flooding Pampa Area (Argentine), S P. Debelis, A A. Bozzo, A Bujan, M B. Barrios Jun 2024

Relationship Of Soil To Native Pasture In A Flooding Pampa Area (Argentine), S P. Debelis, A A. Bozzo, A Bujan, M B. Barrios

IGC Proceedings (1977-2023)

The influence of the topography in soils found in the area surrounding the Chascomús lagoon is examined. The study of the profiles within the representative transect in each microenvironment reveals changes related to its traits. Its relationship with the vegetation present in each toposequence position was observed. The worsening of the natural drainage conditions, are related to reduction of organic matter, increase in the values of pH and PSI, greater intensity of hydromorphic traces and appearance of groups of characteristic species.


Extensification Of Sheep Grazing Systems: Effects On Soil Nutrients, Species Composition And Animal Production, C A. Marriott, I J. Gordon Jun 2024

Extensification Of Sheep Grazing Systems: Effects On Soil Nutrients, Species Composition And Animal Production, C A. Marriott, I J. Gordon

IGC Proceedings (1977-2023)

The effects of ceasing fertiliser inputs to perennial ryegrass/white clover swards, combined with patterns of seasonal grazing, on soil nutrient status, floristic composition and animal production (ewes and single lambs) were studied in a long-term experiment at three upland sites in Scotland. Four unfertilised treatments had a factorial combination of seasonal grazing in summer and autumn at two sward heights (4 and 8 cm). There was also an ungrazed, unfertilised control and a fertilised treatment (140 kg N/ha plus maintenance P and K), grazed at 4 cm sward height in both seasons. All treatments were imposed annually from 1990/91. By …


Grassland Management For Geese: Sustainable Use For Conservation And Agriculture, S M. Percival, R Lilley Jun 2024

Grassland Management For Geese: Sustainable Use For Conservation And Agriculture, S M. Percival, R Lilley

IGC Proceedings (1977-2023)

Increasing numbers of overwintering wild geese have caused considerable problems to agriculture but are often also of conservation concern as their populations are relatively small. Islay, Scotland, is one site where this problem is particularly acute. We studied the two goose species which use this site, the barnacle goose, Branta leucopsis, and the white-fronted goose, Anser albifrons flavirostris, and found that they preferred younger pastures located closer to their roost sites. These preferred areas could be important in developing a sustainable strategy for future goose management. Further non-sustainable population increases might be avoided by increasing disturbance in these areas.


Isolation And Identification Of Entomopathogenic Fungi From The Soils Of Northwest Iran And Their Biological Control Efficacy On The Flour Moth (Ephestia Kuehniella) [Research Note], Mohadeseh Moghasem, Manizheh Jamshidi, Reza Khakvar, Sevil Nematollahi Jun 2024

Isolation And Identification Of Entomopathogenic Fungi From The Soils Of Northwest Iran And Their Biological Control Efficacy On The Flour Moth (Ephestia Kuehniella) [Research Note], Mohadeseh Moghasem, Manizheh Jamshidi, Reza Khakvar, Sevil Nematollahi

The Philippine Agricultural Scientist

Entomopathogenic fungi have the potential to serve as alternatives to or supplements for chemical pesticides in insect biocontrol, with many of these fungi being utilized in commercial and integrated pest control practices globally. This study aimed to isolate and evaluate the efficacy of various entomopathogenic fungi for the biocontrol of the flour moth, Ephestia kuehniella (Lep: Pyralidae). Multiple isolates of entomopathogenic fungi were acquired from soils across different districts of Azerbaijan province in northwest Iran, and their virulence against E. kuehniella larvae was assessed. Seventeen isolates representing diverse entomopathogenic fungi were isolated and purified using the soil trap method from …


Evaluation Of Essential Oils And Their Major Components For Disease Resistance, Serkan Tokgöz May 2024

Evaluation Of Essential Oils And Their Major Components For Disease Resistance, Serkan Tokgöz

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Essential oils (EOs) are natural hydrophobic compounds, which are highly complex, typically comprising 20 to 60 constituents, with two or three main components making up 20% to 95% of their composition, alongside other minor constituents. Research has firmly established the potent antibacterial and antifungal properties of EOs and their primary components. To assess their efficacy, one EO, nutmeg oil, and seven main components, including safrole, toscanol, safraleine, cinnamaldehyde, carvacrol, carvone, and thymol, were tested against four economically significant fungal pathogens (Alternaria solani, Fusarium graminearum, Rhizoctonia solani, and Sclerotiorum sclerotiorum), one oomycete pathogen (Phytium ultimum …


Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso Apr 2024

Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso

IGC Proceedings (1977-2023)

Results from a series of six comparative lamb grazing trials with temperate forages are summarised, and compared with results from the literature. Condensed tannin (CT) concentrations in the diet ranged from 0.12% to 0.47% on a dry matter (DM) basis. Values were generally similar for Yorkshire fog (Holcus lanatus), perennial ryegrass (Lolium perenne) and annual ryegrass (L. multiflorum), each grown with white clover (Trifolium repens), in similar circumstances. Concentrations for tall fescue (Festuca arundinacea)/white clover pastures were relatively low, but may have been artefacts. Drenching with polyethylene glycol (PEG) to bind …


Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake Apr 2024

Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake

IGC Proceedings (1977-2023)

A study was carried out to evaluate the tannin content and crude protein degradation of leaves and twigs from indigenous browsable trees which provide feed for grazing livestock on natural rangelands of Botswana. These browses include the families Leguminosae (Acacias), Capparidaceae (Boscias), Combretaceae (Combretum) and Tiliaceae (Grewias). These were found to be of good nutritive value, with the leaves having a high content of crude protein (9 - 16%) and a wide range of dry matter digestibility (37 - 69.82%). The correlation between crude protein disappearance and tannin content was found to be negative (-0.582) and significant (P<0.05).


Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush Apr 2024

Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush

IGC Proceedings (1977-2023)

The rate of formation of nitrate and ammonium in the soil under dung patches was compared for dung from animals fed either ryegrass (Lolium perenne)/white clover (Trifolium repens) or ryegrass/Lotus pedunculatus forage. Tannin derived from the Lotus did not inhibit ammonification in the soil under dung but nitrate formation was strongly inhibited. The results support the theory that polyphenolics may bind to nitrite in acid soils and cause immobilisation of mineral nitrogen. Apart from their effect of reducing the proportion of dietary nitrogen excreted in urine, tannins in animal diets may make a further contribution to …


Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer Apr 2024

Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer

IGC Proceedings (1977-2023)

A feeding trial was carried out to determine the effect of extractable condensed tannins (ECT) concentration and tannin astringency in tropical legumes on nitrogen (N) digestion by sheep. Test legumes were Desmodium ovalifolium (Do) and Flemingia macrophylla (Fm) which had similar concentrations of Extractable CT (9% DM) but tannins with different degree of astringency (Do, 0.6 and Fm, 0.3 g protein bound/g of ECT). Chopped sun-dried forage of each legume was sprayed with either water (control) or polyethylene glycol (PEG, 3.5% DM) to reduce ECT and fed to 8 sheep with ruminal and duodenal canulas arranged in a replicated 4 …


Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn Apr 2024

Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn

IGC Proceedings (1977-2023)

The in vitro precipitation of ribulose-1,5-bisphosphate carboxylase (Rubisco) by condensed tannin (CT) extracted from Lotus corniculatus and Lotus pedunculatus and the effect of these CT on the in vitro rumen degradation of Rubisco was used to compare the reactivity of these CT. The chemical structure of CT from Lotus corniculatus was homogenous with epicatechin stereochemistry and mostly procyanidin units. The CT from Lotus pedunculatus was heterogenous with mostly prodelphinidin units. The amount of CT required to precipitate all the Rubisco when total soluble leaf protein was incubated with CT from Lotus corniculatus and Lotus pedunculatus was similar. Although CT from …


Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye Apr 2024

Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye

IGC Proceedings (1977-2023)

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin …


Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani Apr 2024

Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani

IGC Proceedings (1977-2023)

The transformation of Lotus corniculatus plants with the maize gene Sn, reorganizes the tissue specificity of condensed tannins accumulation. In particular the transformed plants show an increase of tannin content in roots and a decrease in leaves. Molecular and enzymatic analyses suggest that the transgene can functionally substitute an endogenous unknown gene not expressed in roots and induces its silencing when it is expressed. These findings could have applications for reducing tannin content in unpalatable plants and for cloning genes involved in tannin synthesis.


Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. Mcmahon, M Goto, T A. Mcallister, G A. Jones, K J. Cheng Apr 2024

Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. Mcmahon, M Goto, T A. Mcallister, G A. Jones, K J. Cheng

IGC Proceedings (1977-2023)

Alfalfa and sainfoin leaves were lyophilized and ground (A, S, respectively) or were fractionated into soluble (ASOL, SSOL) and insoluble (AINS, SINS)components and lyophilized and incubated in vitro with diluted ruminal fluid for 24h. Whole leaf and soluble fractions were also incubated with polyethylene glycol 8000 (PEG). Gas production (GP), ammonia concentration [NH3] and volatile fatty acid (VFA) production were lower (P< 0.05) from S and SSOL than from A and ASOL Insoluble fractions differed only in [NH3] (SINS < AINS, P < 0.05). Inclusion of PEG increased (P < 0.05) GP, [NH3] and VFA production from whole leaf and soluble fractions of sainfoin, but not alfalfa. Inactivating the condensed tannins in sainfoin with PEG overcame differences in degradability between these two forages.


Differences In Chemical Composition Among Provenances Of Tree Fodder Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya Apr 2024

Differences In Chemical Composition Among Provenances Of Tree Fodder Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya

IGC Proceedings (1977-2023)

Studies were initiated in a subhumid Southern African environment to assess the chemical composition and nutritive value of Acacia angustissima (Mill.) Kuntze, Calliandra calothyrsus Meiss. and Leucaena species. The objective was to determine variability in crude protein (CP) concentration, acid detergent fibre (ADF), neutral detergent fibre (NDF), and soluble and insoluble proanthocyanidins from fodder samples of species, subspecies and provenances. A wide range was found in these parameters. The implications of these chemical composition factors, especially proanthocyanidins, on the use of these browse fodders in livestock feeding systems are discussed.


Nutritional Implications Of Bound Proanthocyanidins, H P.S Makkar, K Becker Apr 2024

Nutritional Implications Of Bound Proanthocyanidins, H P.S Makkar, K Becker

IGC Proceedings (1977-2023)

The correlation between protein binding capacity of proanthocyanidin-rich neutral detergent fiber (NDF) and their proanthocyanidin (PAs) content was very low (r = -0.21; n = 6). These PAs-rich NDF did not affect growth of a tannin-sensitive strain of Clostridium perfringens. A substantial amount of bound PAs (75 to 92 %) disappeared from the NDF in 24 h of fermentation in an in vitro incubation medium containing rumen microbes. Addition of a tannin-binding agent, polyethylene glycol to the incubation medium containing rumen microbes and browses made free of extractable tannins or NDF rich in bound PAs increased the gas production up …


Environmental Effect On New Released Genotypes Of Graminaceous And Leguminous Forage Perennial Crops, P Martiniello, G Genier, R Allerit Apr 2024

Environmental Effect On New Released Genotypes Of Graminaceous And Leguminous Forage Perennial Crops, P Martiniello, G Genier, R Allerit

IGC Proceedings (1977-2023)

Genotypes of perennial leguminous (alfalfa) and graminaceous (cocksfoot and tall fescue) were evaluated for adaptability in a typical Mediterranean environment (Foggia, southern Italy). The species were field evaluated to detect biomass yield potential under different types of watering. Irrigations were applied considering rainfall and FAO cultural growth coefficient for reintegrating the 75% of the evaporated water from Class A water pan. The forage harvest was applied when the shoots of the varieties reached the 10 and 50% of flowering and heading stage for leguminous and graminaceous, respectively. A split-plot experimental design, with irrigation in the main plot, was adopted. The …


Plant Tannins- Their Role In Forage Legume Quality, J A. Alokan, V A. Aletor Apr 2024

Plant Tannins- Their Role In Forage Legume Quality, J A. Alokan, V A. Aletor

IGC Proceedings (1977-2023)

Forage legumes, especially browse plants, are important in the maintenance and survival of ruminant animals. However many browse species contain high levels of polyphenolic compounds including tannins. The effects of tannins on the quality of forages are reviewed. These include reduction in palatability and intake of feeds, growth rate, digestion of fibre fractions and nitrogen utilization by animals.


Genetic Manipulation Of Sainfoin Leaf Tannins, M Y. Gruber, P Auser, G Lees, A D. Muir, M Wood Apr 2024

Genetic Manipulation Of Sainfoin Leaf Tannins, M Y. Gruber, P Auser, G Lees, A D. Muir, M Wood

IGC Proceedings (1977-2023)

An isogenic population of sainfoin (Onobrychis viciifolia Scop.) plants was developed by two methods; regeneration after long term tissue culture and plant transformation with an antisense chalcone synthase gene. Tannin (proanthocyanidin) content could be dramatically increased in untransformed callus by long term culture, but was not significantly altered in regenerating plantlets. Some of the mature transgenic plants had dramatically reduced levels of leaf tannin. The antisense gene was eliminated from all transgenic plants later in development.


Induction Of Mutants With Ectopic Expression Of Condensed Tannins, M Y. Gruber, B Skadhauge, P Auser, A D. Muir, K K. Thomsen, J Stougaard, B Coulman, D Von Wettstein Apr 2024

Induction Of Mutants With Ectopic Expression Of Condensed Tannins, M Y. Gruber, B Skadhauge, P Auser, A D. Muir, K K. Thomsen, J Stougaard, B Coulman, D Von Wettstein

IGC Proceedings (1977-2023)

Leaves of 47,000 Lotus japonicus plants were screened using a butanol:HCl histochemical test to select “gain of function” mutants. These plants were progeny from L. japonicus lines which were transformed with T-DNA constructs containing either the maize Ds or Ac transposon (Thykjaer et al., 1995). Among 21 putative leaf tannin mutants, five (tan1-5) were characterized for synthesis of condensed tannins, leucocyanidin reductase activity and the presence of Ac and the selectable marker gene, nptII . A range of leaf tannin content among other Lotus species was also characterized.


A Revised Method Of Condensed Tannin Analysis In Leucaena Spp., S A. Dalzell, G L. Kerven Apr 2024

A Revised Method Of Condensed Tannin Analysis In Leucaena Spp., S A. Dalzell, G L. Kerven

IGC Proceedings (1977-2023)

The proanthocyanidin (butanol-HCl) assay was used to measure condensed tannin (CT) in extracts from Leucaena spp. at the University of Queensland. Inconsistent results were found to be caused by the iron catalyst in the butanol/HCl reagent and the presence of ascorbic acid in the sample matrix which enhanced anthocyanidin development. In addition, preparation of sample extracts by back extraction with organic solvents reduced CT recoveries. An accurate and rapid technique was developed that measures CT directly in 70% aqueous acetone 0.1% (w/v) sodium metabisulphite plant extracts.


The Effect Of Condensed Tannins In Lotus Spp. On The Lesser Migratory Grasshopper, C F. Hinks, G L. Lees, M Y. Gruber, A D. Muir, J Soroka Apr 2024

The Effect Of Condensed Tannins In Lotus Spp. On The Lesser Migratory Grasshopper, C F. Hinks, G L. Lees, M Y. Gruber, A D. Muir, J Soroka

IGC Proceedings (1977-2023)

Hatchling grasshoppers (Melanoplus sanguinipes Fab.) fed one accession of field grown big trefoil (Lotus uliginosis Schkuhr) containing a tannin content of 56 mg. g-1 FW, had a significantly lower mean weight than hatchlings fed field grown Lotus species and accessions with lower tannin content. Adult female grasshoppers fed L. uliginosis foliage with 32.3 mg.g-1 FW tannin also ate more feed and had a 2-fold higher gut trypsin and chymotrypsin activity than adults fed low tannin L. corniculatus foliage (0.13 mg.g-1 FW tannin). In more controlled experiments, growth at 20o C or 30o C was used to increase tannin …