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

Plant Pathology Commons

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

11,630 Full-Text Articles 25,553 Authors 2,138,635 Downloads 94 Institutions

All Articles in Plant Pathology

Faceted Search

11,630 full-text articles. Page 81 of 532.

Agrobacterium Mediated Transformation In Forage Legumes, F Damiani, F Pupilli, S Arcioni, M Pezzotti 2025 CNR

Agrobacterium Mediated Transformation In Forage Legumes, F Damiani, F Pupilli, S Arcioni, M Pezzotti

IGC Proceedings (1977-2023)

Plant transformation is a promising tool for plant breeding. It allows the introgression in the plant genome of alien genes. At the moment few, if any, genes of agronomical value have been cloned and are available for genetic engineering works ; on the contrary, some genes encoding for antibiotic resistance are available. The use of these genes allows an easy detection of transformation events and confers useful characters for in vitro selection. A direct application of antibiotic resistance is in the selection of hybrid colonies after protoplast fusion ofparentals resistant to different antibiotics. Transformation using Agrobacterium tumef aciens or Agrobacterium …


An In Vitro Chromosome Doubling Method For Interspecific Hybrids Of Trifolium, Claire Moussett-Declas, J A. Anderson, Elisabeth G. Williams, N L. Taylor 2025 INRA

An In Vitro Chromosome Doubling Method For Interspecific Hybrids Of Trifolium, Claire Moussett-Declas, J A. Anderson, Elisabeth G. Williams, N L. Taylor

IGC Proceedings (1977-2023)

Over 60 interspecific hybrids have been made in the genus Trifolium (Cleveland, 1985), some of them representing attempts to introduce persistance or pest resistance into culti­vated clovers. Most of these hybrids, however, have been ster­ile. To attempt to restore fertility, colchicine methods have been applied to mature hybrid plants in vivo, but with limited success. A routine, simple technique for chromosome doubling in vegetative meristems is therefore still required, particularly for sterile hybrid materials which are available as mature veg­etative clones rather than seed. We have adapted for use with clover hybrids the in vitro chromosome doubling technique used by …


Plant Regeneration By Somatic Embryogensis From Leaf Explants Of Digitaria Eriantha (Steud) Subsp. Eriantha, M Paula Watt, D J. Mycock, C F. Cresswell 2025 University of Natal (Durban)

Plant Regeneration By Somatic Embryogensis From Leaf Explants Of Digitaria Eriantha (Steud) Subsp. Eriantha, M Paula Watt, D J. Mycock, C F. Cresswell

IGC Proceedings (1977-2023)

The most important objective of pasture planning in Southern Africa is to provide grazing during the winter dry months when veld production is either low or of poor quality. Digitaria eriantha (Steud) subsp eriantha is an indigenous per­ennial grass which is drought tolerant and retains its high palat­ability after winter frosts. The successful establishment of this grass as winter forage in the dryland rural areas is, however, impaired by its requirement for fertilizer dressing in the form of nitrogen and phosphate. A considerable amount of research has been undertaken in our laboratory on the growth, photosynthesis and nitrogen metabolism of …


A New Mutant With Open Corolla Tube In Red Clover, L Spiss, Halina Goral 2025 Agricultural University, Poland

A New Mutant With Open Corolla Tube In Red Clover, L Spiss, Halina Goral

IGC Proceedings (1977-2023)

Floral modifications which may promote bee foraging on leguminous forage crops are always interesting to plant breeders since they may contribute to increased seed setting. Reports related to the length of corolla tube, nectar volume, and its availibility in red clover, including tetraploid forms, have been quite frequent in the literature for many decades. Other corolla tube modifications in this species have been described very rarely (Jablonski, 1974, Taylor and Snead, 1986). The purpose of this paper is to describe corolla tube modifications found in red clover and their usefulness in improving bee pollination.


Apomixis And Sexuality In Brachiaria I. Biochemical And Cytoembriological Studies, R Cruz, W Miles, J W. Roca, G De la Cruz, H Ramirez 2025 CIAT

Apomixis And Sexuality In Brachiaria I. Biochemical And Cytoembriological Studies, R Cruz, W Miles, J W. Roca, G De La Cruz, H Ramirez

IGC Proceedings (1977-2023)

The characteristics of Brachiaria such as variability, adequate adaptation to poor soils and its reproductive sexual­apomitic system justify the emphasis made for its genetic improvement for reducing the limitations of the most import­ant varieties. Presently, it is one of the most important genera in the tropics (Lavidan, 1988) with an ample germplasm which needs to be studied and characterized. The objective of this work was to contribute to the identifi­cation of the species and ecotypes using isoenzymatic patterns and to learn the levels of sexuality and apomixis of the ecotypes used.


Sex Linkage Of Growth And Forage Attributes In Buffalograss (Buchloe Dactyloides), J A. Quinn 2025 Rutgers University - Camden

Sex Linkage Of Growth And Forage Attributes In Buffalograss (Buchloe Dactyloides), J A. Quinn

IGC Proceedings (1977-2023)

Buchloe dactyloides (Nutt.) Engelm. is a perennial, sod-form­ing shortgrass of central North America (Hitchcock, 1951), thriving under semiarid conditions and increasing under mod­erate to heavy grazing (Quinn, 1987). The species is largely dioecious, and sex ratios are either 1 : 1 or female-biased (Quinn and Engel, 1986). Isolated plants under controlled conditions are strictly male, strictly female, or monoecious (0 to 20 %, depending on the population). Over the last half-century, buffalograss has been widely used in central North America for reseeding depleted rangelands and for erosion control (Quinn, 1985), and recently it has received renewed attention as a turf …


Phylogenetics Of Apomictic Paspalum Dilatatum, B L. Burson 2025 USDA, Agricultural Research Service

Phylogenetics Of Apomictic Paspalum Dilatatum, B L. Burson

IGC Proceedings (1977-2023)

Paspalum dilatatum Pair., dallisgrass, is a warm-season grass native to South America. There are several biotypes of this species and common dallisgrass is the most prevalent. It is an important pasture grass throughout the warmer regions of the world but has two major impediments-low fertility and suscep­tibility to ergot (Claviceps paspali). Improvement efforts have been unsuccessful because the common biotype is a complex natural hybrid with an unbalanced genomic composition and an obligate apomict, a form of asexual reproduction that has prevented improvement by conventional plant breeding methods. To circumvent this apomictic barrier, phylogenetic investiga­tions were initiated to …


Regulation Of Apomixis In Buffelgrass, D L. Gustine, R T. Sherwood, I Gounaris 2025 USDA, Agricultural Research Service

Regulation Of Apomixis In Buffelgrass, D L. Gustine, R T. Sherwood, I Gounaris

IGC Proceedings (1977-2023)

The apomixis program at the Pasture Laboratory has the long-term objective of finding procedures to manipulate the type of embryo sac which develops in crop species. We would like to induce at will, formation of functional apomictic embryo sacs in obligately sexual species such as maize and wheat, and to induce sexual reproduction in obligate apomicts, such as dallisgrass. The benefits of this capability for plant breeding would be enormous : 1) desirable characteristics could be reproduced over generations in normally sexual genotypes through induced apomixis and 2) genetic variability in apomic­tic genotypes could be unlocked through sexual crosses. Angiosperms …


Cytological And Histological Mechanisms Of 2n Pollen Formation In Hybrid Napier Grass, Y K. Cheng, K T. Lo, Y S. Sheng 2025 Taiwan Livestock Research Institute

Cytological And Histological Mechanisms Of 2n Pollen Formation In Hybrid Napier Grass, Y K. Cheng, K T. Lo, Y S. Sheng

IGC Proceedings (1977-2023)

Hybrid pennisetum is an interspecific hybrid between pearl millet (Pennisetum americanum) and napier grass (P. purpureum). The combing of good characteristics of these two species by hybridization was reported (Cheng, 1984). The hyb­rids are triploid, 2n = 21, and propagated vegetatively. Thus a fertile hybrid would offer opportunities for seed production and forage improvement through hybridization. 2n gametes has been used recently as an alternative method to chemical treatments in a breeding program. The objectives of this inves­tigation were to search for triploid hybrid pennisetum which would produce 2n pollen and to determine the cytological and histological origin of …


Apomixis And Sexuality In Brachiaria Decumbens Stapf., C B. do Valle, Y H. Savidan, L Jank 2025 EMBRAPA

Apomixis And Sexuality In Brachiaria Decumbens Stapf., C B. Do Valle, Y H. Savidan, L Jank

IGC Proceedings (1977-2023)

Brachiaria decumbens Stapf is a perennial tropical forage grass, native to east African savannas. It was introduced to Brazil in the 1960's and is now widely cultivated over 30 million hectares in Central Brazil alone. The two commercial varieties are apomictic tetraploids (2n = 4x = 36), producing uniform progeny, and were selected for their high dry matter production and persistence on poor acid soils. They lack, however, resist­ance to spittlebugs (Deois spp., Zulia spp., Aeneolania spp.) and produce forage of low nutritive value, especially during the dry winter months. The absence of natural variability associated to apomictic reproduction has …


Amelioration De La Qualite Du Fourrage Chez La Fetuque Elevee (Festuca Arundinacea Schreb.), W Pietraszek, J F. Chosson 2025 RAGT

Amelioration De La Qualite Du Fourrage Chez La Fetuque Elevee (Festuca Arundinacea Schreb.), W Pietraszek, J F. Chosson

IGC Proceedings (1977-2023)

Tres interessante dans nos climats pour son rendement et sa rusticite, la Fetuque elevee demande toutefois, pour etre davan­tage utilisee, qu'un effort de selection soit fait pour ameliorer sa qualite. Celle-ci est essentiellement determinee par l'appeti­bilite, l'ingestibilite et Ia digestibilite qui ne peuvent etre mesurees directement que par des troupeaux d'animaux. Leur mesure implique que !'on dispose d'une quantite importante de materiel vegetal et de plus le maintien et la manipulation des animaux sont lourds et couteux. Le selectionneur devrait done pouvoir disposer d'autres cri­teres, indirects, pour pouvoir estimer Ia qualite de son materiel vegetal dans Jes premiers stades du …


Using Diverse Species To Improve Quality And Yield In The Pennisteum Genus, W W. Hanna, M Dujardin, W G. Monson 2025 USDA, Agricultural Research Service

Using Diverse Species To Improve Quality And Yield In The Pennisteum Genus, W W. Hanna, M Dujardin, W G. Monson

IGC Proceedings (1977-2023)

Pearl millet, Pennisetum glaucum (L.) R. Br., and napier­grass, P. purpureum Schum., are two of the major forage pro­ducing Pennisetum species in the tropics and subtropics. Pearl millet is known for its high quality forage and significant pro­gress has been made in developing improved cultivars (Hanna, et al., 1988). Napiergrass has been successfully crossed with pearl millet to produce high quality and high yielding perennial interspecific (PMN) forage hybrids (Hanna and Monson, 1980 and Muldoon and Pearson, 1979). A germplasm evaluation program and an interspecific hybri­dization program at Tifton, GA (Hanna and Dujardin, 1985) has resulted in the identification of …


Forage Yield And Quality Of Orchardgrass And Tall Fescue Under Simulated Acid Precipitation, J H. Reynolds, J D. Wolt 2025 University of Tennessee

Forage Yield And Quality Of Orchardgrass And Tall Fescue Under Simulated Acid Precipitation, J H. Reynolds, J D. Wolt

IGC Proceedings (1977-2023)

Cool-season forage grasses have received less attention than other crops with regard to their sensitivity to acid precipitation even though they are especially well-adapted to portions of the eastern U.S.A. where acid precipitation with a pH less than 4.5 has been documented. Tall fescue (Festuca arundinacea Schreb.) is perhaps the most widely grown cool-season grass in the transition zone of the eastern U.S.A. where it occupies from 12 to 14 million hectares. Orchardgrass (Dactylis glomerata L.) is also widely grown in the eastern U.S.A. Workers in Oregon, such as Cohen et al., 1982, have found few effects on forage yield …


Selection Des Graminees Fourrageres Pour La Qualite: Des Criteres Bases Sur Des References Avec Animaux, M Gillet, J Scehovic, M Marton, L Huguet 2025 INRA

Selection Des Graminees Fourrageres Pour La Qualite: Des Criteres Bases Sur Des References Avec Animaux, M Gillet, J Scehovic, M Marton, L Huguet

IGC Proceedings (1977-2023)

La selection des fourrages pour la qualite exige l'utilisation de criteres indirects. Ceux-ci devraient etre etablis par correla­tion avec des criteres mesures sur animaux: Cela necessite un nombre suffisant de genotypes de qualite differente. 11 faut done que la selection pour la qualite ait deja en partie reussi. A defaut, les selectionneurs utilisent souvent des correlations eta­blies en faisant varier le stade de la plante. Mais sont-elles vala­bles pour comparer des genotypes a stade egal? Ils utilisent aussi les preferences des animaux (« appetibilite ») car cela per­met de comparer plusieurs genotypes avec un seul lot d'ani­maux (Jadas-Hecart, 1982; Gillet …


Variability For Mineral Concentrations Contained In High-Digestible Cell Fractions In Orchardgrass, S Saiga, H Yoneya, K Iwane, K Watanabe 2025 Iwate University

Variability For Mineral Concentrations Contained In High-Digestible Cell Fractions In Orchardgrass, S Saiga, H Yoneya, K Iwane, K Watanabe

IGC Proceedings (1977-2023)

Metabolic disorders of ruminants including grass tetany are associated with mineral imbalances of forage. Powell et al. (1978) found that lambs on tall fescue utilized Ca, P, and Mg less efficiently although the concentrations were rather higher than in the other grasses. As there are large differences in char­acteristics among orchardgrass (Dactylis glomerata L.) culti­vars, the efficiency of minerals also must differ in different culti­vars. For one reason, it is considered that the efficiency to ruminants is due to the rate contained in digestible cell fraction. The objectives of this study were to determine seasonal change of cell fractions, …


The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia, G Moseley, D M. Baker, D H. Hides 2025 AFRC/IGAP

The Efficacy Of A High Magnesium Italian Ryegrass Cultivar In Alleviating Hypomagnesamia, G Moseley, D M. Baker, D H. Hides

IGC Proceedings (1977-2023)

Hypomagnesaemia continues to cause serious economic losses in grazing livestock and recent evidence suggests that its incidence may be increasing. The disease is characterised by a drop in the concentration of magnesium in extracellular fluid and occurs in two forms, chronic and acute. Both forms give rise to classical clinical symptoms which may either result in death or drastically reduced levels of production. The body does not contain a major source of labile magnesium nor does it have a homeostatic mechanism for controlling the level of magnesium in extracellular fluid. The maintainance of normal levels therefore depends almost entirely on …


The Breeding Of Pasture Varieties Of Alfalfa (Medicago Sativa), J M. Piskovatsky, V A. Katov, G V. Stepanova 2025 All Union Fodder Research Institute

The Breeding Of Pasture Varieties Of Alfalfa (Medicago Sativa), J M. Piskovatsky, V A. Katov, G V. Stepanova

IGC Proceedings (1977-2023)

The work of developing new pasture varieties of alfalfa has been conducted in the All-Union Fodder Research Institute from 1975 onwards. The pasture varieties must be persistent under grazing, and must have a high competitive ability in mix­tures with grasses : meadow fescue, timothy and others.


Evaluation And Selection Of The Salt-Tolerant Alfalfa, Geng Huazhu 2025 Chinese Academy of Agricultural Sciences

Evaluation And Selection Of The Salt-Tolerant Alfalfa, Geng Huazhu

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa) as a good forage has b��en popu­larly cultivated for a long time in China. Now it is mainly distributed in the north of the Yangtse River, and covers about 1.3 million hectares in the 14 provinces and regions. It can be planted in the saline-alkali areas, accept alluvial plains and hill regions, for instance, the North of Jiangsu, East of Hebei, North-west of Shandong and Xingjiang. The alfalfa is success­fully used in improving and utilizing the saline-alkali soils for developing animal husbandry in the Gangzhou District of Hebei Province, where its planting area is increasing rapidly, …


Use Of New Methods For Grass And Legume Breeding In Western Region Of The Soviet Union, R Dapkus 2025 Lithuanian Agricultural Research Institute

Use Of New Methods For Grass And Legume Breeding In Western Region Of The Soviet Union, R Dapkus

IGC Proceedings (1977-2023)

The climatic conditions of the Western region of the Soviet Union are favourable for grassland production which provides the major part of forage for livestock nutrition. In raising grassland productivity, new varieties play an important role. Adapted varieties with high yield potential must be used. For developing such varieties, the Fodder Crops Breeding Centre fbr the Western region of the Soviet Union was estab­lished at the Lituanian Agricultural Research Institute in 1972 on the basis of experience since 1922, when selection of herbage species was initiated there. During the past twenty years, breed­ing work has progressed rapidly. At present, breeding …


Cool Season Grazing Of Winter-Active Lucernes, J.G H. White, W J. Lucas 2025 Lincoln College

Cool Season Grazing Of Winter-Active Lucernes, J.G H. White, W J. Lucas

IGC Proceedings (1977-2023)

In New Zealand, lucerne (Medicago sativa L.) is commonly grazed with sheep for much of the year, but winter production is low and alternative, higher-cost feeds need to be provided. However, in most lucerne-growing areas, winters are relatively mild (Lincoln June-August mean temperature 6.2°C), and the recent release of cool-season active cultivars has resulted in considerable farmer interest in winter grazing of lucerne. Stan­dard winter dormant cultivars such as Wairau are normally grazed once in early June for aphid control (Smallfield et al., 1980), then remain ungrazed for at least three months. Cool­season active cultivars are known to produce …


Digital Commons powered by bepress