Genetic Manipulation Of Sainfoin Leaf Tannins,
2024
Agriculture & AgriFood Canada
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,
2024
Agriculture & Agrifood Canada
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.,
2024
The University of Queensland, Australia
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,
2024
Agriculture & Agrifood Canada
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 …
The Effectiveness Of Different Formulations Of Glyphosate Herbicides Under Simulated Rainfall Conditions In Controlling Various Weeds,
2024
Master Program of Agronomy, Faculty of Agriculture, Universitas Padjadjaran
The Effectiveness Of Different Formulations Of Glyphosate Herbicides Under Simulated Rainfall Conditions In Controlling Various Weeds, Syifa Fajriani, Denny Kurniadie, Uum Umiyati
Jurnal Kultivasi
Herbicide effectiveness is affected by herbicide formulation, rainfall, and weed type. Differences in glyphosate salt formulations and 2,4 D amine mixtures may result in variations in the herbicide's ability to wash off the herbicide due to rain. The aim of this study was to assess the effectiveness of different glyphosate herbicide formulations under varying rainfall in controlling various weeds. The experiment took place in a controlled greenhouse environment, utilizing a split plot experimental design with four replications. The main plot was assigned to six different rainfall timings: 0 hours after application (HAA), 1 HAA, 2 HAA, 3 HAA, 4 HAA, …
Developmental Characteristics And Renovating Pattern Of Reed Canarygrass Shoots In A Sward,
2024
Niigata University
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,
2024
CIATA, Spain
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,
2024
Menoufia University
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,
2024
Universite de Caen, France
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.
Intraspecific Competition In Lucerne And Relationships With Reserve Availability,
2024
INRA, I.R.B.A, France
Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud
IGC Proceedings (1977-2023)
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.,
2024
Universite Caen cedex, France
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 (1977-2023)
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,
2024
INIA La Estanzuela
Cynodon Dactylon Control In Conservation Tillage Systems, A Rios, J M. Sanz
IGC Proceedings (1977-2023)
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,
2024
Buenos Aires University
Legume Seedling Development In No Till Pasture Establishment, J L. Rossi, V A. Deregibus
IGC Proceedings (1977-2023)
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,
2024
Instituto Sperimentale Colture Foraggere
Water Relations In Berseem Cultivars Under Drought Stress, A Iannucci, A Rascio, M Russo, P Martiniello
IGC Proceedings (1977-2023)
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,
2024
Wageningen Agricultural University
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 (1977-2023)
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,
2024
INIA, Chile
Ecotypic Adaptation Of Medicago Polymorpha Along A Gradient In Central Chile: Growth And Seed Production, A Del Pozo, C Ovalle, J Avendano
IGC Proceedings (1977-2023)
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,
2024
Brazzaville, Congo
Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza
IGC Proceedings (1977-2023)
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,
2024
Instituto Biologico
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 (1977-2023)
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,
2024
CSIRO, Australia
Effect Of Phosphorous Fertiliser On The Competition Between Two Tropical Grasses And Two Tropical Legumes, F D. Hu, R J. Jones
IGC Proceedings (1977-2023)
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 …
Selection And Agronomic Characterization Of Leucaena Spp. Genotypes For Cold Tolerance. I. Dry Matter Yield.,
2024
INTA, Argentina
Selection And Agronomic Characterization Of Leucaena Spp. Genotypes For Cold Tolerance. I. Dry Matter Yield., M C. Goldfarb, J F. Casco
IGC Proceedings (1977-2023)
Biotypes of Leucaena spp (56) were evaluated in order to identify those with tolerance to low temperature and with desirable characteristics as a forage crop. Selection was done at two phases. Phase I: 92 days old seedlings (n=2800) were subjected at two temperatures treatments during 14 hours: T1= -8 °C and T2= -3 °C. Selection criteria was established as 50% of live leaves remained after treatments were applied. Phase II: Plants that survived phase I were planted at field conditions and agronomic characteristics were measured. Seventeen plants were selected from eleven different biotypes, resulting one from T1 and the rest …
