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Articles 3421 - 3450 of 9451

Full-Text Articles in Agricultural Science

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.


Cattle Toxicity From Woolly Locoweed (Astragalus Mollissimus): A Case Study In Central New Mexico, Casey N. Spackman, Clint A. Stonecipher, Daniel Cook Jun 2024

Cattle Toxicity From Woolly Locoweed (Astragalus Mollissimus): A Case Study In Central New Mexico, Casey N. Spackman, Clint A. Stonecipher, Daniel Cook

Poisonous Plant Research (PPR)

Livestock toxicity resulting from poisonous plants poses a significant challenge for ranchers, particularly concerning locoweeds (Astragalus spp. or Oxytropis spp.). This study investigated a case of cattle poisoning in central New Mexico, where clinical signs were consistent with locoweed toxicity. Rangeland conditions were hot and dry following earlier spring rains, promoting advantageous environmental conditions for a locoweed outbreak. Analysis of Woolly locoweed (Astragalus mollissimus) and animal samples from the ranch confirmed the presence of swainsonine, a key toxin in locoweeds. It can be concluded that the likely cause of cattle losses was locoweed toxicity, highlighting the …


Herbicides, Department Of Primary Industries And Regional Development, Western Australia Jun 2024

Herbicides, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Herbicides play a vital role in integrated weed management programs. Knowledge of the mechanisms and activity of herbicides will improve the impact and sustainability of herbicides as a weed management tactic. This fact sheet is a guide to the types of herbicides available and when and how they should be used.


Herbicide Application, Department Of Primary Industries And Regional Development, Western Australia Jun 2024

Herbicide Application, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Herbicides can be applied by a variety of means, including boom sprayers, aerial spraying, misters, blanket wipers, rope wick applicators, weed seekers and back-pack sprayers. This fact sheet reviews the different methods, including nozzles and calibration of equipment, used to apply herbicides.


Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee May 2024

Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee

LSU Master's Theses

Studies were conducted in 2021 through 2023 at the LSU AgCenter Dean Lee Research and Extension Center near Alexandria, LA to determine the sensitivity of 2,4-D- or dicamba- tolerant cotton (Gossypium hirsutum L.) to an early season application of a Group 15 and foliar-only herbicides. Both studies were randomized complete block designs with a two-factorial arrangement of treatments with four replications. In the dicamba-tolerant cotton study, Factor A consisted of no foliar-herbicide, dicamba alone, glyphosate alone, or dicamba plus glyphosate. Factor B consisted of either no Group 15 residual herbicide, acetochlor, or S-metolachlor. In the 2,4-D- tolerant cotton …


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 …


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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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.