Open Access. Powered by Scholars. Published by Universities.®

Plant Pathology Commons

Open Access. Powered by Scholars. Published by Universities.®

4,558 Full-Text Articles 12,249 Authors 752,811 Downloads 89 Institutions

All Articles in Plant Pathology

Faceted Search

4,558 full-text articles. Page 5 of 175.

A Predictive Model Of Vegetation Dynamics Under Grazing, C.P. D. Birch, B R. Werkman, L W. Partridge 2024 Macaulay Land Use Research Institute

A Predictive Model Of Vegetation Dynamics Under Grazing, C.P. D. Birch, B R. Werkman, L W. Partridge

IGC Proceedings (1997-2023)

This quantitative model predicts changes in the species composition of grazed vegetation. It is based on growth equations for each species represented. The three parameters in each equation represent maximum production rate, maximum standing biomass, and the decline of production rate at high total plant density. Parameters may be varied with environmental factors. The model is generic, but is illustrated using values for four taxa growing under red deer (Cervus elaphus) grazing on the Isle of Rhum, Scotland: bent/fescue grassland (Agrostis/Festuca), purple moor-grass (Molinia caerulea), mat-grass (Nardus stricta) and heather (Calluna …


Collection And Evaluation Of The Section Platycarpe From The Peoples Republic Of China, T A. Cambell, G Bao, Z L. Xia 2024 USDA, Agricultural Research Service

Collection And Evaluation Of The Section Platycarpe From The Peoples Republic Of China, T A. Cambell, G Bao, Z L. Xia

IGC Proceedings (1997-2023)

The Peoples Republic of China is the center of origin of several species of the section Platycarpae, which could contain genes for drought and cold tolerance that would be of significant benefit to cultivated alfalfa (Medicago sativa L.) Of particular interest are Medicago archiducis-nicolai Sirjaev, M. edgeworthii Sirjaev, and M. ruthenica (L.) Ledebour. Of 105 M. ruthenica accessions collected from 15 diverse environments in Inner Mongolia, 50 were evaluated in the field at Beltsville MD (USA) in 1993 and 1994 on an acid soil (pH 6.4) deficient in boron and potassium. Significant variation was noted for stand retention, reaction to …


Integrating Satellite Images And Species-Based Vegetation Maps To Manage Native Grasslands, M Hall-Beyer, Q.H. J. Gwyn 2024 Universite de Sherbrooke

Integrating Satellite Images And Species-Based Vegetation Maps To Manage Native Grasslands, M Hall-Beyer, Q.H. J. Gwyn

IGC Proceedings (1997-2023)

Satellite image mapping of grasslands is problematic when species diversity occurs at a sub-pixel scale. We propose a method, called melody classification, to map ground cover units that group several spectral classes (colours). Melodies are defined as the normalized expected frequencies of each class within the ground cover unit. Starting from an unsupervised classification, an image is created showing the probability of finding each spectral class in the vicinity of each pixel. Each pixel is classified by comparing the melody in its neighbourhood with that of each ground cover unit. Accuracies are greatly enhanced over those of supervised classification. Melody …


Verification Of And Genetic Variation Between Stylosanthes Sp. Aff. S. Scabra Accessions, C J. Liu 2024 CSIRO

Verification Of And Genetic Variation Between Stylosanthes Sp. Aff. S. Scabra Accessions, C J. Liu

IGC Proceedings (1997-2023)

Thirty-three Stylosanthes accessions, which are all considered to be S. sp. aff. S. scabra, were analysed using STS and RAPD as genetic markers. These accessions were readily clustered into two major groups based on dissimilarity values, with 28 accessions in one group (A) and the other five in the other (B). STS analysis indicated that accessions in group A are diploid S. sp. aff. S. scabra but those in B are tetraploids, likely to be S. scabra or its closely related taxa. Cytological examination of root-tip cells confirmed that the five accessions in group B are all tetraploids. Genetic dissimilarity …


Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak 2024 McGill University

Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak

IGC Proceedings (1997-2023)

A study was conducted with ALCELLR - lignin (A-lignin) to evaluate its impact on performance of grain- fed veal calves. Thirty two male calves (avg. initial wt, 190 kg) were fed for 13 weeks grain corn and a protein supplement with added A-lignin to supply 0, 1.25%, 2.5% or 5.0% of diet. Eight other calves were used to study nitrogen balance, and grab samples of faeces were analyzed for anaerobic, aerobic and coliform bacteria. A-lignin at 1.25% of diet increased (p<.01) weight gain by 12%. Addition of A-lignin also decreased (p< 0.01) organic matter digestion, increased (p<.01) faecal N excretion but did not significantly alter N balance. A-lignin reduced (p< 0.01) faecal ammonia concentration but increased (p <.01) DM content of grab samples of faeces; there were no significant effects on populations of faecal microorganisms. The study revealed a beneficial effect of A-lignin on calf growth but the reason for the response was not uncovered.


Qualitative Evaluation Of D.H.P. (Dihidroxipiridine) In The Urine Of Buffaloes Fed With Leucaena, P B. Alcantara, T A. Ferreira, D A. Beisman, A.M F. Pereira 2024 Instituto de Zootecnia

Qualitative Evaluation Of D.H.P. (Dihidroxipiridine) In The Urine Of Buffaloes Fed With Leucaena, P B. Alcantara, T A. Ferreira, D A. Beisman, A.M F. Pereira

IGC Proceedings (1997-2023)

The aim of this study was to evaluate the DHP elimination in the urine of buffaloes fed with three levels of leucaena (0,10 and 20g of leucaena's DM/kg LW0.75), plus corn silage at 2.5% of LW in D.M. The main purpose was to estimate the levels of mimosine toxicity in those resistant animals. Data showed that DHP started to be eliminated at the first urination in both levels of leucaena. This occurred one hour after ingestion. DHP was present up to the third urination (5 hours after ingestion) in the highest level.


Genomic Cloning Of Fasciola Hepatica Excretory-Secretory Antigenic Genes In E. Coli, Xu Heng, Zheng Li, Liu Shigui, Shen Bin, Wu Fend 2024 Sichuan Union University

Genomic Cloning Of Fasciola Hepatica Excretory-Secretory Antigenic Genes In E. Coli, Xu Heng, Zheng Li, Liu Shigui, Shen Bin, Wu Fend

IGC Proceedings (1997-2023)

A complementary DNA (cDNA) library was constructed from the mRNA of adult worms of Fasciola hepatica in the expression vector gt11, the size of the library contained approximately 2.4 x 105 recombinants and the recombinant efficiency was 85%. The library was directedly screened with a rabbit antisera raised against a excretory-secretory (ES) antigen of Fasciola hepatica. Two positive clones of strong signal were selected from a group of 200 positive clones, named FH3 and FH7. The length of external fragments of two recombinants were 0.85Kb (FH3) and 1.15Kb (FH7). The E.coli 1089 host was infected by recombinants FH3 and FH7 …


Effect Of Plant Species On The Development And Vertical Migration Of Larvae Of Gastrointestinal Nematodes Which Parasitise Sheep, J H. Niezen, W.A. G. Charleston, J Hodgson, C M. Miller, H A. Robertson 2024 AgResearch Grasslands, Flock House Agricultural

Effect Of Plant Species On The Development And Vertical Migration Of Larvae Of Gastrointestinal Nematodes Which Parasitise Sheep, J H. Niezen, W.A. G. Charleston, J Hodgson, C M. Miller, H A. Robertson

IGC Proceedings (1997-2023)

The development and migration of gastrointestinal nematode larvae on a range of herbage species were compared following a series of standardised contaminations with sheep faeces over two years. In 1992/93, greatest numbers of larvae were recovered from browntop (Agrostis capillaris cv Grasslands Muster), cocksfoot (Dactylis glomerata cv Grasslands Kara), ryegrass (Lolium perenne cv Grasslands Nui) and Yorkshire fog (Holcus lanatus cv Massey Basyn) while the lowest numbers were recovered from white clover (Trifolium repens cv Grasslands Huia) with the other herbages intermediate. In 1993/94, highest numbers were recovered from Yorkshire fog and ryegrass, lowest numbers from …


Seed Proteinase Inhibitors From Annual Medics Active Against Insect Pests, M Odoardi, A Tava, F Ceciliani 2024 Istituto Sperimentale Colture Foraggere

Seed Proteinase Inhibitors From Annual Medics Active Against Insect Pests, M Odoardi, A Tava, F Ceciliani

IGC Proceedings (1997-2023)

Several different species of annual medics have been tested for the occurrence and concentration of trypsin inhibitors in the seed. Trypsin Inhibitory Activity (TIA) has been in fact related to the level of resistance to biotic and abiotic stresses. Wide variation was found for TIA among species, with the highest values shown by the snail medic (Medicago scutellata). After a simple and rapid procedure of chromatographic purification, the Trypsin Inhibitor (TI) from snail medic has been tested towards the trypsin-like proteinases extracted from larvae of different phytophagous insects, showing high levels of Inhibitory Activity. The complete amino acid …


The Effect On Intake Palatability And Digestibility Of Phenolic Compounds In Tagasaste (Chamaecytisus Proliferus), N J. Edwards, J C. Mailey, D M. McNeill, J B. Lowry, C S. McSweeney, D A. Henry, C M. Oldham 2024 The University of Western Australia

The Effect On Intake Palatability And Digestibility Of Phenolic Compounds In Tagasaste (Chamaecytisus Proliferus), N J. Edwards, J C. Mailey, D M. Mcneill, J B. Lowry, C S. Mcsweeney, D A. Henry, C M. Oldham

IGC Proceedings (1997-2023)

The major secondary metabolites currently identified in tagasaste (Chamaecytisus proliferus) belong to the phenolic group of compounds. The principal phenolic compounds are the flavones, apigenin and luteolin, but low concentrations of condensed tannins, the isoflavonoid daidzein and the alkaloid sparteine have also been detected in some samples. No flavonols have been detected. There is a strong relationship between the concentration of phenolic compounds in tagasaste and its palatability. Furthermore, digestibility of tagasaste is relatively high throughout the year, thereby implicating intake as the major factor influencing the seasonality of liveweight performance of livestock grazing tagasaste. Despite confirmation of …


Effect Of Endophyte-Infected Tall Fescue Hay On Dairy Heifers Under European Intensive Management, J C. Emile, J P. Ravault, J M. Chabosseau 2024 INRA

Effect Of Endophyte-Infected Tall Fescue Hay On Dairy Heifers Under European Intensive Management, J C. Emile, J P. Ravault, J M. Chabosseau

IGC Proceedings (1997-2023)

Two fields were established at Lusignan (France) with the same variety of tall fescue but differing in the rate of Acremonium coenophialum seed infestation : 0 % = E- ; 100 % = E+. Dairy heifers were fed ad libitum with E- or E+ hay and were given in addition 1.7 kg DM of concentrates. No effect was noticed on the intake (5.65 vs 5.63 kg DM) as well as on ADG (874 vs 838 g/d) regarding E- vs E+ hay resp. However, prolactin concentration was significantly halved when heifers were fed with the E+ hay. More temperate climatic conditions …


Feeding Strategies To Optimize Reproductive Performance Of Cattle Grazing High Protein Pastures In Uruguay, H R. Tosi, K M. Wittenberg 2024 CARECO

Feeding Strategies To Optimize Reproductive Performance Of Cattle Grazing High Protein Pastures In Uruguay, H R. Tosi, K M. Wittenberg

IGC Proceedings (1997-2023)

Alternative feeding strategies were investigated for Holstein heifers grazing a vegetative red, Trifolium pratense L., and white clover, Trifolium repens L., pasture. A total of 474 grazing heifers were supplemented varying amounts of corn silage, Zea mays, during the breeding season in an effort to improve reproductive performance. Animal response to supplementation, whether on spring or winter pasture, was similar. Corn silage supplemented at 18.8 or 28.8% DM basis of total diet, for winter and spring pastures, respectively, resulted in animal weight gains similar to that of heifers receiving legume pasture only. Serum urea nitrogen and reproductive performance for heifers …


Strategies For Improving Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, J C. Waller, H A. Fribourg 2024 University of Tennessee, Knoxville

Strategies For Improving Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, J C. Waller, H A. Fribourg

IGC Proceedings (1997-2023)

A beef (Bos taurusL.) cattle producer must allocate land and forage resources to meet nutrient needs of the entire herd. Using 20 yr of calving and grazing data, templates of herd composition, associated Total Digestible Nutrients (TDN) requirements over the whole year, and forage TDN production were developed for a typical herd and land area. The monthly energy needed by the entire herd was relatively constant. Forage productivity varied monthly, indicating the need to plan for efficiently using surplus TDN from some seasons to meet needs at other times. This approach could be expanded to include more definitive …


Eneficial Use Of Grasses Artificially Infected With Endophytes, Non-Toxic To Animals, G.C M. Latch, L R. Fletcher 2024 AgResearch, Palmerston North, New Zealand

Eneficial Use Of Grasses Artificially Infected With Endophytes, Non-Toxic To Animals, G.C M. Latch, L R. Fletcher

IGC Proceedings (1997-2023)

Information presented in this paper demonstrates that Ryegrass Staggers does not occur in animals which graze ryegrasses (Lolium sp.) artificially infected with a strain of Acremonium endophyte which does not produce the tremorgenic toxin lolitrem B. Peramine is produced by the endophyte and this alkaloid protects the grass from attack by Argentine stem weevil. New Zealand farmers have used a ryegrass cultivar infected with this strain of endophyte for the past four years and there are no reports of Ryegrass Staggers in animals grazing it. Strains of endophytes have been found in other grasses which do not produce toxins …


The Effect Of Ryegrass Endophyte On Milk Production From Dairy Cows In Northern New Zealand, E R. Thom, D A. Clark, C D. Waugh, R J. McCabe, V T. van Vught, B.J L. Kock 2024 Dairying Research Corporation

The Effect Of Ryegrass Endophyte On Milk Production From Dairy Cows In Northern New Zealand, E R. Thom, D A. Clark, C D. Waugh, R J. Mccabe, V T. Van Vught, B.J L. Kock

IGC Proceedings (1997-2023)

The aim of this study was to compare the milk production of cows grazing endophyte-infected perennial ryegrass (Lolium perenne L.) pasture with those grazing endophyte-free pastures. High and nil endophyte ryegrass pastures were drilled with and without white clover (Trifolium repens L.) in autumn 1993. White clover was completely removed in autumn 1995. High endophyte pastures had >85% of tillers infected but nil endophyte pastures were rapidly contaminated with endophyte-infected ryegrass and had 50% infection by autumn 1996. Losses in milk production due to endophyte were small (<6%), and occurred in only 2 of the 6 three week test periods. Cows showed clinical symptoms of ryegrass staggers in summer/autumn 1995 but not in 1996. Heat stress symptoms were absent. Losses of milk production occurred when lolitrem B levels were low (spring 1994) and when cows did not show clinical staggers (summer 1996). Other chemicals or agronomic factors could be important determinants of the milk production responses.


Use Of Willows (Salix Spp) As Drought Fodder For Sheep, S K. Oppong, P D. Kemp, G B. Douglas, B T. Bulloch 2024 Massey University

Use Of Willows (Salix Spp) As Drought Fodder For Sheep, S K. Oppong, P D. Kemp, G B. Douglas, B T. Bulloch

IGC Proceedings (1997-2023)

The effects of cutting height and harvesting times on the forage yield, yield components and quality of Tangoio hybrid willow and Kinuyanagi willow were examined, to evaluate these willows as drought fodder for sheep. Tangoio (3.8 tDM/ha) outyielded Kinuyanagi (3 tDM/ha) in edible forage production and provided reasonable quality fodder (nitrogen content of 2.0 % and digestibility of 65 -69 %). The high edible forage yield of the willows relative to pasture (0.8 tDM/ha) during January and April showed that they provided potentially valuable supplements to pasture production. The willows, especially Tangoio, are recommended for use as maintenance fodder for …


Interaction Of Symbiont Alkaloid Accumulation And Growth, L P. Bush, M A. do Valle Ribeiro, J Hogan, P B. Burruss II 2024 University of Kentucky

Interaction Of Symbiont Alkaloid Accumulation And Growth, L P. Bush, M A. Do Valle Ribeiro, J Hogan, P B. Burruss Ii

IGC Proceedings (1997-2023)

Several classes of alkaloids are present in tall fescue (Festuca arundinacea Schreb.) and the tall fescue-endophyte (Neotyphodium [=Acremonium] coenophialum [Morgan-Jones and Gams] Glenn, Bacon and Hanlin comb.nov.) association. Experiments were conducted to determine the effect of the endophyte on seed germination and seedling growth and to measure the effect of host perloline concentration on endophyte development and loline accumulation. Seed germination was not altered by the presence of the endophyte. In non-stress field conditions of Ireland emergence of first leaf occurred sooner and dry weight was greater in endophyte infected seedlings than endophyte free seedlings, whereas no significant differences …


Enviornmental Quality And Production Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, H A. Fribourg, J C. Waller 2024 University of Tennessee, Knoxville

Enviornmental Quality And Production Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, H A. Fribourg, J C. Waller

IGC Proceedings (1997-2023)

The establishment, longevity, and utilization of mixed Acremonium coenophialum endophyte-infested (E+) and endophyte-free (E-) tall fescue (Festuca arundinacea Schreb.) pastures were evaluated in three beef production experiments. In Experiment-1, E-, 80% E+ , and a sward of alternate sets of four drill rows of E+ and E- were compared under put-and-take grazing. Stand density of E- was inadequate after 3 yr, but stands and animal performance of the other treatments were similar for 4 yr. Wide strips (6-7 m) of E- fescue were established (Experiment-2) subsequently with no-till methods in E+ fescue sods after destruction of the original vegetation …


The Assimilating And Benefit Of The Chinese Reed Canarygrass (Phalaris Arundinacea L.) On Soil Nutrition, Zhou Bihua, Qi Guang 2024 Zhelimu Animal Husbandry College

The Assimilating And Benefit Of The Chinese Reed Canarygrass (Phalaris Arundinacea L.) On Soil Nutrition, Zhou Bihua, Qi Guang

IGC Proceedings (1997-2023)

The Chinese Reed Canarygrass (Phalaris arundinacea L.) is a fine perennial herbage of Gramineae. The wild ripened seeds were collected and sown on the experimental field of the Zhelimu Animal Husbandry College. The former plant of experimental plot is Chinese Crabapple and the cultivating layer is light loam with pH 8.7. The content of nitric N is 33.58 kg/ha, amino N 42.54 kg/ha, organic P 5.6 kg/ha, k 55.97 kg/ha. Clones were set up according to different compositions, that is N, P, K, WP, NPK, CK. the total amount of fertilizer is 23.8 g. The coefficient of absorbing and …


On Designing The Meadow Agrocenosis Of The Polissya (Region) Of Ukraine, V F. Shchesyuk, A Y. Baluta, O V. Shchesyuk 2024 Volyn Research and Production Association

On Designing The Meadow Agrocenosis Of The Polissya (Region) Of Ukraine, V F. Shchesyuk, A Y. Baluta, O V. Shchesyuk

IGC Proceedings (1997-2023)

Geobotanical studies of the natural meadow associations in the wetland areas of the Polissya rivers of the Ukraine were conducted. The Polissya represents a forested region and the rivers include the Western Buh, Vyzhivka, Turia, Stokhid, and Styr. The dominant species is Digrappis arundinacea with Poa palustris, Bromus inermis, Latirus pretense, Latirus palustris, Vicia sepium, and Urtica dioica as codominants. Research demonstrated that the green feed production of Digrappis arundinacea, in combination with Poa palustris, was significantly greater (9.5 t ha-1) than for Digrappis arundinacea alone while the crude protein content of the forage, at early flowering, …


Digital Commons powered by bepress