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Full-Text Articles in Physical Sciences and Mathematics

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 (1997-2023)

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 …


Developmental Characteristics And Renovating Pattern Of Reed Canarygrass Shoots In A Sward, M Ito, S Mizuno, T Otani, S Kobayashi Apr 2024

Developmental Characteristics And Renovating Pattern Of Reed Canarygrass Shoots In A Sward, M Ito, S Mizuno, T Otani, S Kobayashi

IGC Proceedings (1997-2023)

Developmental and renovating traits of shoots were investigated ecomorphologically in a reed canarygrass (Phalaris arundinacea L., cv. Palaton) sward harvested 3 times per year. Reed canarygrass shoots exhibited notably high growth rates both in the 1st and 2nd crops together with rapid leaf formation (around 7 days/leaf) and active internode elongation. Vigorously growing shoots, which regenerated soon after the 1st cutting and dominated in the 2nd crop canopy, mainly originated from the stubble formed with 3 to 4 phytomers that developed after the beginning of spring growth, thus resulting in higher shoot density than that of the 1st crop. …


Canopy Changes In Healthlands (Erica-Ulex) Grazed By Sheep Or Goats, R Celaya, K Osoro Apr 2024

Canopy Changes In Healthlands (Erica-Ulex) Grazed By Sheep Or Goats, R Celaya, K Osoro

IGC Proceedings (1997-2023)

The grazing effects of sheep and goats on vegetation dominated by heaths (Erica spp) and gorse (Ulex gallii) were studied for two years. Two plots were grazed from May to October 1992 by 7 ewes or 7 does and in the following year each plot was subdivided into two subplots subsequently grazed either by sheep or by goats in a factorial design. During the first grazing season both sheep and goats reduced similarly the cover percentage of shrubs since the herbaceous content was scarce, although goats reduced more the height of the shrubs than sheep. The cover …


Effect Of Nitrogen, Phosphorus, Potassium And Cutting On The Regrowth And Insect Infestation Of A Sorghum And Berseem Clover In Egypt, M B. Attia Apr 2024

Effect Of Nitrogen, Phosphorus, Potassium And Cutting On The Regrowth And Insect Infestation Of A Sorghum And Berseem Clover In Egypt, M B. Attia

IGC Proceedings (1997-2023)

The objective of this study was to determine the minimum quantities of phosphorus and potassium which must be applied with varying amounts of nitrogen in order to maintain maximum hay production and minimum level of insect infestation. This was more pronounced at the higher N rates and caused a significant N x K interaction during each of these years. There was no yield response to applied phosphorus at any N rate. Relation between levels of nitrogen and infestation percentage was positive but infestation rate decreased with the increase of potassium levels while there was no relation between levels of phosphorus …


An Overview Of The Physiology And Biochemistry Of N Reserves Mobilization In Forage Species, F Le Dily, A Ourry, J Boucaud Apr 2024

An Overview Of The Physiology And Biochemistry Of N Reserves Mobilization In Forage Species, F Le Dily, A Ourry, J Boucaud

IGC Proceedings (1997-2023)

Recent works focusing on the physiological and biochemical events associated to perennial forages sustainability (re-growth after defoliation, winter survival), provided evidence that vegetative storage proteins (VSPs, ca proteins stored in remaining organs and specifically mobilized) were key organic compounds for shoot regrowth. Attempts to elucidate environmental conditions involved in VSPs deposit ability of different species are under progress today. In contrast, mechanisms of spring- or cut-induced proteolysis are investigated at a lesser extend. This contribution is an opportunity to summarize our knowledge of N-reserves mobilization and to set the question of VSPs breakdown regulation.


Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud Apr 2024

Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud

IGC Proceedings (1997-2023)

Below-ground reserves are thought to provide an indication of a forage potential for shoot regrowth after defoliation. The aim of this work was to re-evaluate the causal relationships existing between organic reserves (non-structural carbohydrates and N reserves) and shoot regrowth of alfalfa. The variations brought about by cultivar differences (cv Lodi or Europe), length of the previous regrowth period (30 or 45 d), or by intraspecific competition for light within a dense canopy, were studied. Field grown plants were harvested at weekly intervals, and separated as dominant, intermediate and suppressed plants. Shoot regrowth yield was determined and taproot were analyzed …


Seasonal Fluctuations Of Vegetative Storage Proteins And Starch Concentrations In Stolons Of Trifolium Repens L., V Bouchart, A Ourry, J C. Simon, J Boucaud Apr 2024

Seasonal Fluctuations Of Vegetative Storage Proteins And Starch Concentrations In Stolons Of Trifolium Repens L., V Bouchart, A Ourry, J C. Simon, J Boucaud

IGC Proceedings (1997-2023)

The seasonal pattern of nitrogen, starch and vegetative storage protein (VSP) concentrations was studied in the stolons of two Trifolium repens L. genotypes (cv Aran and Rivendel). Maximum concentrations of starch were found in summer months; its hydrolysis occurred in winter, at the time, where VSP and nitrogen were accumulated. The decrease of nitrogen and VSP concentrations occurred during spring, and an inverse relationship was found between VSP concentrations in stolons and mean temperatures. The causal implications of starch and VSP availability on spring regrowth potential are discussed in relation with regulatory mechanism inducing VSP synthesis.


Cynodon Dactylon Control In Conservation Tillage Systems, A Rios, J M. Sanz Apr 2024

Cynodon Dactylon Control In Conservation Tillage Systems, A Rios, J M. Sanz

IGC Proceedings (1997-2023)

Bermudagrass (Cynodon dactylon L. PERS.) is the most important weed in Uruguay. With the development of conservation tillage systems, chemical control of bermudagrass becomes essential. The objective of this research was to evaluate, in a long term integrated program, bermudagrass chemical control during the first year of a pasture. Application of glyphosate and no-tillage seeding of the pasture took place during fall. A 70% reduction of underground part of the weed was detected. The chemical control, together with a conservation tillage system and an adequate pasture management allowed an important reduction in bermudagrass level for the first year pasture. …


Legume Seedling Development In No Till Pasture Establishment, J L. Rossi, V A. Deregibus Apr 2024

Legume Seedling Development In No Till Pasture Establishment, J L. Rossi, V A. Deregibus

IGC Proceedings (1997-2023)

The objective of this study was to compare no-till and conventional seeding of pasture and their effects on legume establishment. The presence of residue cover reduced legume seedling establishment and weed population under no-till seeding. The reduction in establishment was associated with the physical impediment of the residue cover and the decay of seedling vigor when passing through that cover.


Water Relations In Berseem Cultivars Under Drought Stress, A Iannucci, A Rascio, M Russo, P Martiniello Apr 2024

Water Relations In Berseem Cultivars Under Drought Stress, A Iannucci, A Rascio, M Russo, P Martiniello

IGC Proceedings (1997-2023)

Berseem clover (Trifolium alexandrinum L.) is a crop of particular interest in semi-arid regions, used for herbage and hay productions. However, its seed yield is reduced by drought stress that occurs during seed filling. In this study five cultivars (Axi, Big Bee, Lilibeo, Sacromonte and Saniros) subjected to four irrigation frequencies in controlled environment, were compared for their physiological responses to subsequent water stress period (3 days). Some parameters (leaf water potential (), osmotic potential (þ), relative water content (RWC) and gravimetric soil water content (GSWC)) related to plant water status were recorded. Plants subjected to previous periods of …


Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma Apr 2024

Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma

IGC Proceedings (1997-2023)

Light partitioning in a grass-clover mixture was studied using a general competition model. The model assumes a fixed extinction coefficient (k) and no leaf dispersion. This was compared with modelling the effect of different k of both species over height as well as the effect of type of leaf dispersion. These new assumptions led to a better estimation of the light partitioning between both species. For grass the effect of variable k and leaf dispersion was similar and in both cases the total absorbed light was lower than under default conditions. For clover the new assumptions led to a higher …


Ecotypic Adaptation Of Medicago Polymorpha Along A Gradient In Central Chile: Growth And Seed Production, A Del Pozo, C Ovalle, J Avendano Apr 2024

Ecotypic Adaptation Of Medicago Polymorpha Along A Gradient In Central Chile: Growth And Seed Production, A Del Pozo, C Ovalle, J Avendano

IGC Proceedings (1997-2023)

Relative growth rate, total dry weight and seed yield on 19 accessions of burr medic (Medicago polymorpha L.) from different bioclimatic conditions, were assessed at Cauquenes (35°58’;72°17’W) in the subhumid mediterranean region. The accessions were sown in microplots over raised beds during two years (1991 and 1992), and swards cut periodically at 2, 6 and 10 cm height. There were significant differences between accessions in both total dry weight and seed yield (P < 0.001, Table 1), but the interaction between accessions and height of cutting was not significant (P > 0.05). Total dry weight was positive correlated with days to flowering (r2 = 0.81; P > 0.01).


Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza Apr 2024

Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza

IGC Proceedings (1997-2023)

The nitrogen effects on Hyparrhenia diplandra were studied. Plants were grown on nutrient solutions of variable concentrations in nitrogen. The supplied nitrogen increased tillering, leaf production, lamina area, total dry matter accumulation and total nitrogen accumulation in lamina. A detailed examination showed that the effect on tillering was the main cause of the differences observed in dry weights between different treatments. The nitrogen supply elongated significantly the lamina and nitrogen deficiency increased its thickness; but this was not enough to compensate the loss of weight in lower nitrogen treatment. The lamina area as well as nitrogen accumulation in the lamina …


Biochemical And Isoenzyme Analysis Of Seven Pennisetum Purpureum (Schum.) Cultivars, E E. Bach, V B.G. Alacantara, P B. Alcntara, E A. Veasey Apr 2024

Biochemical And Isoenzyme Analysis Of Seven Pennisetum Purpureum (Schum.) Cultivars, E E. Bach, V B.G. Alacantara, P B. Alcntara, E A. Veasey

IGC Proceedings (1997-2023)

This study characterized seven Pennisetum purpureum cultivars, namely cv. Anão, Bajra, Cameroon, Guaçu, Roxo, Taiwan A-144 and Uruckwami, through biochemical analysis, including protein, glucose and fructose contents, and polyacrylamide gel electrophoresis using the esterase system, by sampling 30, 60, 90, 120 and 150 dayold leaves. Cultivar Taiwan A-144 presented the highest number of nodes per stem and percentage of emerging buds. Protein concentration decreased gradually after 60 days for all cultivars, except for Anão. Cultivar Guaçu presented the highest level of glucose in 90 day old plants, whereas Cameroon presented the highest levels at 120 and 150 days. The esterase …


Effect Of Phosphorous Fertiliser On The Competition Between Two Tropical Grasses And Two Tropical Legumes, F D. Hu, R J. Jones Apr 2024

Effect Of Phosphorous Fertiliser On The Competition Between Two Tropical Grasses And Two Tropical Legumes, F D. Hu, R J. Jones

IGC Proceedings (1997-2023)

The effect of P fertiliser on the competition between grass and legume in four grass-legume mixtures : Urochloa mosambicensis cv. Nixon/ Stylosanthes hamata cv. Verano; Nixon/S.scabra cv. Seca; Bothriochloa pertusa cv. Bowen/Verano and Bowen/Seca were studied. Each mixture was grown in a low P, low N soil, in pots. A standard replacement series design with two P levels (0 and 10 kg/ ha equivalent) and 3 replicates were used. Seventy days after sowing, Nixon mixtures outyielded Bowen mixtures, and Verano mixtures outyielded Seca mixtures. P increased top and root yields of all mixtures but there was no significant (p …