Gene Transfer Of Ryegrasses: Down-Regulation Of Major Pollen Allergens In Transgenic Plants,
2024
Swiss Federal Institute of Technology, Lausanne
Gene Transfer Of Ryegrasses: Down-Regulation Of Major Pollen Allergens In Transgenic Plants, X L. Wu, X D. Ye, Z Y. Wang, I Potrykus, G Spangenberg
IGC Proceedings (1977-2023)
The objective of this study is to generate transgenic ryegrass plants with a down-regulation of two major pollen allergenic proteins Lol p I and Lol p II. Antisense vectors for Lol p I and Lol p II cDNAs driven by the pollen-specific promoter Zm13 have been constructed. Corresponding transgenic plants have been recovered by particle inflow gun-mediated microprojectile bombardment of embryogenic suspension cells from perennial and Italian ryegrass using chimeric Act1-hph gene as a selectable marker. Their transgenic nature has been demonstrated by Southern hybridization analysis. The analysis of reproductive development and accumulation of pollen allergens in the transgenic ryegrasses …
Predicting Forage Production From Pasture By Use Of The Delphi Technique,
2024
University of Prince Edward Island
Predicting Forage Production From Pasture By Use Of The Delphi Technique, E Hovingh
IGC Proceedings (1977-2023)
The objective of this study was to determine the effect of various pasture management techniques on the predicted yield of forage from pasture. Twelve researchers, extension and industry personnel in Atlantic Canada participated in the Delphi technique as well as the Conjoint analysis to arrive at estimates for the yield response expected from the use of single pasture management techniques and multiple combinations of the same. The results of the Delphi survey demonstrated that all of the pasture management techniques would increase the yield of forage, from seven percent up to forty-seven percent beyond the yield of unimproved, unmanaged pasture.
Foliar Blight Of Centrosema Pubescens (Benth) At Ibadan In The Lowland Humid Tropics,
2024
University of Ibadan
Foliar Blight Of Centrosema Pubescens (Benth) At Ibadan In The Lowland Humid Tropics, L Ezenwa, N A. Amusa, V O. Oben
IGC Proceedings (1977-2023)
The aetiology and epidemiology of leaf blight of centro (Centrosema pubescens Benth) was investigated at Ibadan in the lowland humid tropics of Nigeria. Rhizoctonia solani was associated with the leaf blight of centro. The pathogen was harboured by itchgrass (Rottboellia cochinchinensis (Lour) Clayton), a weed growing within and outside the centro plot. High inoculum population of 4.0 + 0.3 x 106/g soil was estimated in the soil. The seed of centro were free of R. solani. Field infection of the disease occurs during the peak of the rainy season beginning in patches which later spread causing extensive …
Endophyte Effects In Central European Festuca Pratensis Huds Varieties On Field Emergence And Yield On Various Sites,
2024
Martin-Luther-University Halle-Wittenberg
Endophyte Effects In Central European Festuca Pratensis Huds Varieties On Field Emergence And Yield On Various Sites, W Schoberlein, M Pfannmoller, S Eggestein
IGC Proceedings (1977-2023)
Central European varieties of Festuca pratensis Huds. are sometimes infested by the endophytic fungus Acremonium uncinatum. This paper informs about field trials staged on 9 locations for studying biomass and seed yield of different Festuca pratensis varieties, each endophyte-infested (E+) and endophyte-free (E-). In the E+-variants of 2 selected varieties, which were tested in 17 field experiments for field emergence, the number of emerged plants per m2 was significantly increased in 8 cases, preferably on the same location. Analyses of the biomass yield furnished better results in most E+- variants, albeit seldom on a significant level. However, the average …
The Role Of Endophyte (Acremonium Lolii) In Listronotus Bonariensis Pest Tolerance Of Italian Ryegrass (Lolium Multiflorum), E Torres, E Cisternas, L Angulo
IGC Proceedings (1977-2023)
The objective of this study was to determine the behaviour of new varieties of Italian ryegrass (Lolium multiflorum) and their tolerance to the attack of the Argentine stem weevil (Listronotus bonariensis) in cultivars with and without endophyte (Acremonium lolli). The variety of better behaviour was Aberoscar; although it does not have endophyte, it was not very damaged, the one which leads one to belive there are other factors besides the endophyte influencing this cultivar’s resistance to the Argentine stem weevil. The effect of the endophyte was of little importance in the control of the insect pest.
The Accession Of Grassy Weed Seeds Into The Soil Seedbank Of Grasslands,
2024
University of New England
The Accession Of Grassy Weed Seeds Into The Soil Seedbank Of Grasslands, R.D B. Whalley, T S. Andrews, M R. Gardener
IGC Proceedings (1977-2023)
Perennial grassy weeds of grasslands are usually characterised by substantial and long lived soil seedbanks. A comparison of the potential seed production and accession into the seedbanks of giant Parramatta grass (Sporobolus indicus var. major (Buse) Baaijens) and Chilean needle grass (Nassella neesiana (Trin. & Rupr.) Barkworth) revealed big differences in their potential annual seed production and in the proportion being incorporated into the seedbank. The potential seed production of giant Parramatta grass was about 668,000 seeds m-2 and only about 0.3% of these were incorporated into the seedbank. The figures for Chilean needle grass were 22,000 seeds …
Winterkill Potential Of Alfalfa Under Different Snow Depths,
2024
Michigan State University
Winterkill Potential Of Alfalfa Under Different Snow Depths, R H. Leep
IGC Proceedings (1977-2023)
The presence and amount of insulating winter snow cover are key factors in determining the potential of winter injury of alfalfa (Medicago sativa L.) In the Midwestern U.S. Four alfalfa varieties of varying fall dormancy ratings were planted in the summers of 1993 and 1994. Snow depths above the crop plots were kept constant at depths of 0, 10, and 20 cm during the subsequent winters with framed mesh covers. Winterkill percentages during the two seasons varied dramatically from 0-100% and were significantly higher for the 0 cm treatment than for 10 or 20 cm treatments. Nitro, a nondormant …
The Influence Of Sowing Rate On Ryegrass (Lolium Perenne) And White Clover (Trifolium Repens) Types On The Clover Content In The Ryegrass White Clover Swards,
2024
Carillanca Regional Centre
The Influence Of Sowing Rate On Ryegrass (Lolium Perenne) And White Clover (Trifolium Repens) Types On The Clover Content In The Ryegrass White Clover Swards, O Y. Romero, B N. Butendieck, A C. Sleman
IGC Proceedings (1977-2023)
The objective of this study was to determine whether the sowing rate of ryegrass Nui (Lolium perenne), Giant and Huía white clover (Trifolium repens) influence the clover content in the ruegrass-clover mixed sward. The trial was conducted at the Carillanca Experimental Station. Three sowing rates were studied: 18, 12 and 6 kg/ha for Nui perennial ryegrass and 3, 4.5 and 6 kg/ha for Giant and Huía white clover. The clover content in the sward was increased by reducing the sowing rate of the ryegrass from 18 to 12 and 6 kg/ha or increasing the sowing rate …
Influence Of The Acremonium Endophytes On Agronomic Traits Of Perennial Ryegrass And Tall Fescue In France, C Ravel, F Balfourier, G Charmet
IGC Proceedings (1977-2023)
Seven cultivars of perennial ryegrass (Lolium perenne) with (EI) and without (EF) Acremonium endophytes were compared in trial plots at 5 locations in France. Such a trial was also established with 6 tall fescue (Festuca arundinacea) cultivars in 5 locations. These trials were sown either in 1994 or 1995. Yields and visual traits (rust and drought tolerances, vigour 6-weeks following the sowing) were assessed. The data were analysed by means of variance analysis with two main factors (cultivars and endophyte status) and their interaction. As interaction was not significant, some significant differences between EI and EF …
Acremonium-Endophytes Of Perennial Ryegrass (Lolium Perenne) In France,
2024
INRA
Acremonium-Endophytes Of Perennial Ryegrass (Lolium Perenne) In France, C Ravel, C Astier, F Balfourier, G Charmet
IGC Proceedings (1977-2023)
Infection with endophytic fungi (Acremonium spp.) was detected in seeds of wild populations of perennial ryegrass (Lolium perenne) collected in France by private breeding companies and INRA. In total, 262 populations were examined and 70% contained Acremonium. It is worth noticing that most populations are endophyte infected but generally endophyte infection rates per population were low. Isolation of endophyte from each infected population is under progress and had already shown that the two taxonomic groups of endophytes of perennial ryegrass are present. This work lead to a view of the distribution of Acremonium endophytes from perennial …
Screening Tropical Forage Grasses For Resistance To The Spittlebugs (Homoptera: Cercopidae),
2024
EMBRAPA/CNPGC
Screening Tropical Forage Grasses For Resistance To The Spittlebugs (Homoptera: Cercopidae), J R. Valerio, A P. De Souza
IGC Proceedings (1977-2023)
Spittlebugs are the most damaging pasture pests in tropical America where extensive monocultures of Signal grasses, especially Brachiaria decumbens cv. Basilisk, have favored the buildup of spittlebug populations. Under severe spittlebug attack, the entire above-ground portion of the plant dries and eventually dies, thereby reducing the carrying capacity of infested pastures. Host plant resistance is a low-cost method of controlling spittlebugs. High level of spittlebug resistance is found in the cultivar Marandu (B. brizantha), but it requires more fertile soils. Brachiaria germoplasm is being screened for spittlebug resistance. In the present study, 30 introductions of Brachiaria were evaluated for …
Indicators Of Pathogen Potential Of Pasture Soils,
2024
Grassland Research Centre
Indicators Of Pathogen Potential Of Pasture Soils, R A. Skipp, R N. Watson, G C.M Latch
IGC Proceedings (1977-2023)
A simple pot test was used to indicate the combined effects of several pathogens common in pasture soils (plant parasitic nematodes and pathogenic fungi e.g. Pythium spp.) by comparing the dry weight yields of clover seedlings grown in untreated soil with those from soil treated in a microwave oven. Response to microwave treatment, expressed as a "Soil Pathogenicity Index", was greater with soil from old pasture or from areas in 2 year old pasture plots showing poor regrowth after grazing of white clover (Trifolium repens L) or Caucasian clover (T. ambiguum Bieb.), than from soil from new pasture or …
Impact Of Virus Resistance On White Clover Persistence And Productivity,
2024
USDA, Agricultural Research Service
Impact Of Virus Resistance On White Clover Persistence And Productivity, G A. Pederson, M R. Mclaughlin
IGC Proceedings (1977-2023)
The objective of this study was to compare the virus-resistant white clover (Trifolium repens L.) germplasm SRVR with virus-susceptible cultivars for productivity and persistence under clipping in several different environments. Four cultivars and SRVR were broadcastseeded in the field at Mississippi State, MS in the fall of eight different years. Dry matter yields were taken for 2-4 years after seeding using mowers for defoliation. Virus-resistant SRVR had greater dry matter yields than all four cultivars in the second year, greater than three of four cultivars in the third year, and greater than two of four cultivars in the fourth …
Appearance And Movement Of Fungal Endophyte In Annual Ryegrass,
2024
Texas A&M
Appearance And Movement Of Fungal Endophyte In Annual Ryegrass, L R. Nelson, Chunguang Du
IGC Proceedings (1977-2023)
In this study we investigated the efficiency of fungal endophyte (Acremonium loliii) transmission from plant to seed in annual ryegrass (Lolium multiflorum). Results indicated that the endophyte begins to move up or grow up the plant at about growth stage 30 of Zodoks scale, when day temperatures were near 25° C. In our study, we found that the endophyte was not transmitted to all seed for two reasons. Most importantly, the endophyte was not transmitted into some seedheads even though the plant was infected, indicating the tiller was not infected. Secondly in some infected seedheads, a very small number of …
Influence Of The Fungal Endophyte Acremonium Lolii On Dry Matter Yield Of Perennial Ryegrass In Galcia, Spain,
2024
Centro de Investigaciones Agrarias de Mabegondo
Influence Of The Fungal Endophyte Acremonium Lolii On Dry Matter Yield Of Perennial Ryegrass In Galcia, Spain, J A. Oliveira, J Collar
IGC Proceedings (1977-2023)
A field experiment studying the impact of the ryegrass endophyte (Acremonium lolii), was carried out at two locations in Galicia (Northwest Spain): Mabegondo on the Atlantic coast and Puebla de Brollón in the interior. Of 56 half-sib families of Galician perennial ryegrass (Lolium perenne L.) studied, 28 held endophyte (E+) and the other 28 not (E-). All these families were established in trial plots in 1992. Significant differences between E- and E+ families were obtained, and E+ families had a higher (P < 0.05) first cut, spring and total yield than E- families at Puebla de Brollón (dry location) in the third year after planting. The infection of perennial ryegrass with some strains of A. lolii seems to benefit the host in stressful conditions. In some areas of Galicia, climatic conditions are often stressful for perennial ryegrass and the chances of E+ plants being favored by either natural or artificial selection seems high.
Insecticidal Activity Of N-Formylloline,
2024
University of Kentucky
Insecticidal Activity Of N-Formylloline, D L. Dahlman, M R. Siegel, L P. Bush
IGC Proceedings (1977-2023)
Several insect species were sensitive to N-formylloline, a pyrrolizidine alkaloid found in significant concentrations in tall fescue (Festuca arundinacea L.) infected with Neotyphodium coenophialum (= Acremonium coenophialum) Glenn, Bacon et Hanlin. Topical or injected doses were toxic in a dose dependent manner. Acute doses resulted in quick incapacitation; lower doses caused behavioral changes, uncoordinated movements, tremors, etc. Insects tested included green bug, bird cherry-oat aphid, large milkweed bug, spined soldier bug, American cockroach, house fly, face fly, cat flea and Japanese beetle.
Autecology Of Prosopis Caldenia (Burk.) In The Region Of "Caldenal" Of The Province Of San Luis, Argentina,
2024
F.I.C.E.S-U.N.S.L.
Autecology Of Prosopis Caldenia (Burk.) In The Region Of "Caldenal" Of The Province Of San Luis, Argentina, G E. Gabutti, M.J L. Privitello
IGC Proceedings (1977-2023)
Different estimates of the growth of Prosopis caldenia (Burk.) were related in the area of the “caldén” forest, Province of San Luis: trunk diameter, treetop coverage and total tree height to infer the annual growth percentage. The number of trees per hectare and their distribution was calculated based on size. Pod production per hectare was evaluated to determine forage potential.
Variation In The Stylosanthes Anthracnose Pathogen: Implications For Australian Cultivars,
2024
CSIRO
Variation In The Stylosanthes Anthracnose Pathogen: Implications For Australian Cultivars, Sukumar Chakraborty, Ross Perrott, Maria Jose D'A Charchar, Celso D. Fernandes, Segenet Kelemu
IGC Proceedings (1977-2023)
Isolates of Colletotrichum gloeosporioides which cause anthracnose disease in the tropical pasture legume Stylosanthes were collected from its centre of diversity in South America. These and other isolates from Asia, Africa and Australia were studied using Random Amplified Polymorphic DNA (RAPD) markers and virulence on host differentials to assess the threat to Australian Stylosanthes cultivars from exotic races of this pathogen. A phenetic analysis of 90 isolates using RAPD markers showed a wide genetic diversity in the overall pathogen population. Compared to this, genetic diversity in the Australian population was very limited. A similar situation was noted for pathogenic variation …
Pfra Grazing Management Conserves Biodiversity,
2024
PFRA
Pfra Grazing Management Conserves Biodiversity, B Bristol, T Weins
IGC Proceedings (1977-2023)
Shrinking grassland habitats across Prairie Canada are resulting in increased societal values for biodiversity within the remaining rangeland resources. The Prairie Farm Rehabilitation Administration (PFRA) manages 929,000 hectares in the Prairie and Boreal Plain Ecozones across three Prairie Provinces. Management of these range resources accomplishes two main objectives: (1) sustaining economic viability of the rural community through provision of livestock grazing and (2) conservation of soil, water and biodiversity resources. PFRA uses the tools of inventory, research and management to accomplish these objectives. The 87 pastures are managed toward the “good and excellent” range condition classes which conserves biodiversity and …
Study Of The Diversity Of Soil Animal Community In The Songnen Plain Grassland Of China,
2024
Northeast Normal University
Study Of The Diversity Of Soil Animal Community In The Songnen Plain Grassland Of China, Yin Xiuqin, Zhu Tingcheng, Zhong Weiyan, Peng Wu Kui
IGC Proceedings (1977-2023)
This paper makes a diversity study of 8 habitats of soil animal communities in Songnen plain grassland. The research shows that the better the habitat condition is, the higher the diversity index of soil animals, and the worse the habitat condition is the lower the diversity index of soil animals. The diversity of soil animal communities has a positive relationship with soil organic matter, total nitrogen, and has a negative relationship with pH value. It has no obvious relationship with soil water content and total phosphorus. The diversity of soil animal communities decreases with increasing depth of soil layer and …
