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Articles 1501 - 1530 of 9752

Full-Text Articles in Agronomy and Crop Sciences

The Effect Of N And K Fertilizers On The No3 Content Of Different Grass Species And Mixtures, A Szodfridt, J Varga May 2025

The Effect Of N And K Fertilizers On The No3 Content Of Different Grass Species And Mixtures, A Szodfridt, J Varga

IGC Proceedings (1977-2023)

The major quantity of the annual grassland vegetation comes from the first cut in Hungary because of the continental climate of the country. Next to the energy content of grasses it is important to have informations about the amount of some possible toxic components such as nitrate. The critical NO3- value is considered to be 0.25-0.31 % in DM (Andreev, 1981), NO3 content higher than 0.6 % in DM is toxic (Kemp et al., 1977). Ebert et al. (1977) showed that 120 kg/ha N given for the 1st cut did not raise NO3 content higher than the critical value. K …


Determination Of Condensed Tannins In Tropical Legume Forages, L Telek May 2025

Determination Of Condensed Tannins In Tropical Legume Forages, L Telek

IGC Proceedings (1977-2023)

The effect of condensed tannins (proanthocyanidins) in ruminant nutrition is complex and needs further interdiscipli­nary reinvestigations with improved analytical methods. With the « cell rupture » theory of legume pasture bloat (Howarth et al., 1978), the role of condensed tannins seems to be secondary; they are acting as protein precipitants (Goplen et al., 1980) and inhibiting microbiological proliferation in cell­ular spaces (Howarth et al., 1982). Their assumed interference with digesting enzymes in vivo is doubtful (Mole and Water­man, 1985). On the importance of condensed tannins in nutrition, several reviews were published (McLeod, 1974; Tempel, 1982; Kumar and Singh, 1984 and …


Screening Sericea Lespedeza Germplasm For Tannin Concentration In The Leaves And Herbage Palatability, J C. Petersen, J A. Mosjidis, N S. Hill May 2025

Screening Sericea Lespedeza Germplasm For Tannin Concentration In The Leaves And Herbage Palatability, J C. Petersen, J A. Mosjidis, N S. Hill

IGC Proceedings (1977-2023)

Several million hectares in the subtropical world are currently used as grazing land for beef and dairy cattle, how­ever, in many cases animal production is very low. To improve animal nutrition, cultivated legume species can be introduced. Sericea lespedeza has potential and could be utilized in the acid soils of the· subtropics. Generally, sericea is low in palatability and nutritive value because its leaves contain tannins, which have long been associ­ated with low intake and reduced digestibility. Tannins are responsible for an astringent or bitter taste caused by the pre­cipitation of salivary glycoprotein (Goldstein and Swain, 1963). Chopping or macerating …


The Effect Of Selenium Fertilizer On The Selenium Status Of Sheep Grazing Annual Pasture In South-Western Australia, B R. Whelan, D W. Peter, N J. Barrow, D J. Buscall, V C. Cox May 2025

The Effect Of Selenium Fertilizer On The Selenium Status Of Sheep Grazing Annual Pasture In South-Western Australia, B R. Whelan, D W. Peter, N J. Barrow, D J. Buscall, V C. Cox

IGC Proceedings (1977-2023)

White muscle disease was first reported in grazing livestock in Western Australia by Gardiner (1961). Sheep affected by the disease could be divided into two categories : young suckling lambs in winter and early spring, and weaners and hoggets in summer (Gardiner et al., 1962). Subsequent investigations showed that, while there were few clinical symptoms of sel­enium deficiency, there were probably many sheep suffering from ill-thrift. This sub-clinical deficiency caused reduced liveweight gains, reduced wool production and lowered ewe fertility. It was most noticeable in areas of greater than 600 mm of annual rainfall on the lighter sandy soils with …


Synthesis Of Cell Wall Components In Maize Internodes, J H. Cherney, J J. Volenec, G A. Brown May 2025

Synthesis Of Cell Wall Components In Maize Internodes, J H. Cherney, J J. Volenec, G A. Brown

IGC Proceedings (1977-2023)

Cell wall structure affects intake and digestibility of forages by rummants. Before microbial degradation of cell walls can be understood, it will be necessary to have a better understanding of cell wall formation. Internodes of grasses elongate in a_cropetal succession, with two internodes usually elongating s1multaneously. Elongating internodes consist of three regions : 1) a zone of cell division, 2) a zone of cell elongation, and 3) a zone of secondary cell wall deposition. This tissue provides an excellent system for studying cell wall changes in rapidly developing tissues. Our objectives were to : 1) examine changes in cell wall …


Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland May 2025

Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland

IGC Proceedings (1977-2023)

Sericea lespedeza [Lespedeza cuneata (Dumont-Cours.) G. Don.] is well adapted to acid soils and low fertility but has generally been considered a low-quality forage due to high levels of tannin and indigestible fiber. Tannin levels increase during midsummer (Windham et al. 1988). The most com­monly used assay for tannin in sericea is the vanillin-HCl pro­cedure (Burns, 1963) on oven-dried samples. Oven-drying has been reported to cause increased polymerization or oxidative changes in tannins (Goldstein and Swain, 1963). Fresh-frozen sericea contained higher amounts of extract­able tannin than field-dried forage and fiber digestibility of high-tannin sericea by sheep was much lower …


Maximizing Crop Production And Profitability Through Double Cropping Corn And Soybean Systems In South Carolina, Bennett Harrelson May 2025

Maximizing Crop Production And Profitability Through Double Cropping Corn And Soybean Systems In South Carolina, Bennett Harrelson

All Dissertations

Profitability is critical for farm sustainability, efficiency, and longevity. Over the last decade, corn and soybean commodity prices have fluctuated considerably, and more recently, extreme increases in input prices have narrowed profit margins. Non-traditional cropping systems that can boost profit are becoming of interest to farmers in South Carolina, specifically double cropping soybean behind corn. In this scenario, corn is harvested at high moisture contents and followed by ultra-late planted soybean. However, prior research related to the agronomic production practices of double cropping corn and soybean is minimal. To develop best management practices for growers interested in double cropping corn …


Mechanisms Of Perennial Sorghum Resistance To Sugarcane Aphid Infestation, Esha Kaler May 2025

Mechanisms Of Perennial Sorghum Resistance To Sugarcane Aphid Infestation, Esha Kaler

Department of Entomology: Dissertations, Theses, and Student Research

Sorghum, Sorghum bicolor (L.) Moench, the fifth most-grown cereal crop in the world, is a versatile crop, grown across different agro-ecological regions. Sorghum has numerous uses ranging from food and forage purposes to biofuel production. Sugarcane aphid (SCA; Melanaphis sacchari) is a major threat to sorghum production, accounting for 50% to 100% yield loss under heavy infestations. Perennial sorghum can be a sustainable and climate-resilient alternative to the current cereal farming systems. The development of perennial sorghum offers numerous benefits, such as reduced economic inputs, more carbon sequestration, better soil health, and sustainable yields. We employed host plant resistance …


Integrating Genomic And Phenomic Breeding Tools For Wheat Stem Sawfly Resistance In Hard Winter Wheat, Sydney E. Graham May 2025

Integrating Genomic And Phenomic Breeding Tools For Wheat Stem Sawfly Resistance In Hard Winter Wheat, Sydney E. Graham

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The wheat stem sawfly (WSS; Cephus cinctus) is an insect pest that affects wheat (Triticum aestivum) in the Northern Great Plains. This pest causes stem cutting that makes the plants susceptible to lodging and results in up to 30% yield loss. The primary management strategy for producers is utilizing host plant resistance, for which the main trait is stem solidness. This trait increases the pith thickness and provides resistance to the WSS by increasing larval mortality and reducing stem cutting. While stem solidness is largely controlled by a known major gene (SSt1), the phenotypic expression is also …


Anaerobic Soil Disinfestation As A Non-Chemical Management Option Against Fungi And Heterotrophic Bacteria In Organic Sweetpotato Production, Meredith Tucker May 2025

Anaerobic Soil Disinfestation As A Non-Chemical Management Option Against Fungi And Heterotrophic Bacteria In Organic Sweetpotato Production, Meredith Tucker

All Theses

North Carolina is the largest producer of sweetpotatoes in the United States, with South Carolina increasing farming acreage to 2,501 in 2022 compared to 1,300 in 2017. Growers producing conventional and organic sweetpotatoes are equally challenged with managing fungal pathogens due to fungicide resistance or fungicides being unavailable due to environmental regulations, leading many to shift to growing organic crops. Anaerobic soil disinfestation (ASD) is a non-chemical pre-plant management option that uses a carbon amendment, irrigation, and plasticulture to establish an anaerobic environment in soils, killing soil microbes. A greenhouse study was conducted to assess ASD on fungal pathogens and …


Investigate The Use Of Nucleic Acids As Pesticides To Manage Major Pests And Pathogens Of Crops In South Carolina, Prasanna Valavanur Shekar May 2025

Investigate The Use Of Nucleic Acids As Pesticides To Manage Major Pests And Pathogens Of Crops In South Carolina, Prasanna Valavanur Shekar

All Dissertations

The sugarcane aphid (SCA, Melanaphis sorghi), first discovered on grain sorghum in late 2013, has gradually become a major insect pest of sorghum. It inflicts significant damage to the crop year after year, causing millions of dollars in losses throughout the sorghum-producing regions of the United States. Similarly, Armillaria root rot—also referred to as oak root rot—is a major cause of decline in peach (Prunus persica) production in the southeastern United States. This disease is caused by Armillaria mellea and Armillaria tabescens. Current management practices for controlling M. sorghi include the use of synthetic pesticides, resistant varieties, and regular scouting. …


Heterologous Expression Of Maize-Derived Antimicrobial Peptide Zmes4 In Escherichia Coli For Potential Plant Pathogen Control, Suseno Amien, Dadi Nurdiana, Noor Istifadah, Noladhi Wicaksana, Haifanisa Salsabila Apr 2025

Heterologous Expression Of Maize-Derived Antimicrobial Peptide Zmes4 In Escherichia Coli For Potential Plant Pathogen Control, Suseno Amien, Dadi Nurdiana, Noor Istifadah, Noladhi Wicaksana, Haifanisa Salsabila

Jurnal Kultivasi

ZmES4 is a plant-derived antimicrobial peptide (AMP) from maize that shows promise as a biocontrol agent against plant pathogenic organisms. In the context of growing challenges in sustainable agriculture, AMPs like ZmES4 represent innovative alternatives to chemical pesticides. This study focuses on the structural characterization and heterologous expression of the ZmES4 peptide in Escherichia coli (E. coli). The gene encoding ZmES4 was obtained from the maize female gametophyte (NCBI Reference Sequence: NM_001112150.3) and cloned into the pET24d(+) expression vector using NcoI and XhoI restriction sites. Transformation into E. coli BL21 (DE3) cells enabled recombinant expression upon induction with isopropyl β-D-1-thiogalactopyranoside …


Grassland For Our World, F Riveros Apr 2025

Grassland For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world 's grazing lands are a finite resource nnd, overall, are being badly mnnaEed; in most developing countries action is required now, before it is too lnte. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will con


Human Impact On Terrestrial Ecosytems- What We Know And What We Are Doing About It, H A. Mooney Apr 2025

Human Impact On Terrestrial Ecosytems- What We Know And What We Are Doing About It, H A. Mooney

IGC Proceedings (1977-2023)

At present the impact of humankind on the Barth System is substantial mul will become greater as we continue to add over 80 million people to the global population each year. Collectively the human species utilises over a third of the total fresh water that is available, as well as an equivalent amount of tho total terrestrial productivity. Possil energy is being consumed at a prodigious rnte and fuels, among other things, over a half a billion vehicles. To support the large human population the Earth has been greatly reconfigured with much of the land utilised for grazing and agriculture. …


Grasslands For Sustainable Ecosystems, Malcolm Hadley Apr 2025

Grasslands For Sustainable Ecosystems, Malcolm Hadley

IGC Proceedings (1977-2023)

Grasslnnds present many advantages for examining issues related to sustainability. Grasslands include planted pastures as well as a variety of natural rangelands in situations ranging from semi-arid to subhumid. Diversity is also reflected in the spectrum of grassland users and uses, for example, nomadic pastoralism, extensive ranches, intensive pastures, wildlife tourism, game hunting. And in terms of sustainability of resource management, grasslands encompass a wide range of contrasting situations and conflicts in resource use. Heavy grazing pressure associated with increasing human populations in certain tropical savannas, the implications of rural depopulation to traditional pasture management in alpine regions, and the …


Red Clover Hybrid Ryegrass Associations Results Obtained From 1984 To 1987 In Four French Regions, C Pfitzenmeyer, C Longueval Apr 2025

Red Clover Hybrid Ryegrass Associations Results Obtained From 1984 To 1987 In Four French Regions, C Pfitzenmeyer, C Longueval

IGC Proceedings (1977-2023)

In France, red clover is often grown in association with a grass in order, if not to increase the yield of forage, at least to improve its quality by having a larger protein content in the harvested product. Among the grass species associated to red clover, Italian ryegrass, too aggressive a competitor, is replaced more and more by hybrid ryegrass. The aims of the present work were the following

1% to obtain quantitative references on the behaviour o[ hybrid ryegrass/red clover associations in four contrasting regions of France ;

2% to check that the presence of clover, through the transfer …


Potentials Of Summer Fodders Under Intensive Cropping System In India, M S. Tiwana, Thakur Singh Apr 2025

Potentials Of Summer Fodders Under Intensive Cropping System In India, M S. Tiwana, Thakur Singh

IGC Proceedings (1977-2023)

One of the reasons for low milk production in India is the non-availability of good quality fodders in sufficient quantity. Therefore, it is necessary to bridge the gap of this acute short­age of fodder for increasing the milk production. There seems to be no possibility of increasing area under fodders and the only alternative looks to be the ulilization of vacant land (70 days) after harvesting wheat and before the sowing of main summer season crops. However, the growing of these crops may have some effect on the yield of succeeding crops by depleting or replenishing the nutrient status of …


Competitive Effects On Production Of Lolium Perenne L. And Trifolium Alexandrinum L. In Mixture And Mono-Culture, M S. Tiwana, K P. Puri, I S. Thind Apr 2025

Competitive Effects On Production Of Lolium Perenne L. And Trifolium Alexandrinum L. In Mixture And Mono-Culture, M S. Tiwana, K P. Puri, I S. Thind

IGC Proceedings (1977-2023)

Berscem (Trifolium alexandrinum L.) is grown as a fodder crop by every farmer of north India. Though it is a very good multi-cul legume fodder, yet its dry matter percentage is low which indirectly affects the total dry matter production over a period of 6 to 7 months. Presently no suitable multicut grass for the same period is available which may be grown separately or in mixture with berseem to produce high dry matter yield. The first successful planting of ryegrass in research trials was made in 1976 (Tiwana and Puri, 1984) in India. After that, we became interested …


Herbage Yield Of Annual Ryegrass (Lolium Multiflorium Lam.) And Common Vetch (Vicia Sativa L.) At Different Seeding Rates, M A. Jimenez, O L. Gallegos, M.J L. Castrellon Apr 2025

Herbage Yield Of Annual Ryegrass (Lolium Multiflorium Lam.) And Common Vetch (Vicia Sativa L.) At Different Seeding Rates, M A. Jimenez, O L. Gallegos, M.J L. Castrellon

IGC Proceedings (1977-2023)

Most of the dairy farms in the Central Valley of Mexico have alfalfa and corn silage as major forages. Winters are mild, how­ever, yield of alfalfa is reduced and no corn can be grown. For­age crops as oats, annual ryegrass and common vetch have been grown successfully to supply winter forage (Avendano, 1978; Victoria, 1981). Annual rycgrass generally outyields oats, but a high input of nitrogen is required by annual rye grass (Ciane, 1978). The high cost of N fertilizers prevents their use and cheaper N sources should be sought. Legumes as common vetch grown with annual ryegrass can be …


Performance Of White Clover Cultivars In Mixtures With Orchardgrass In Atlantic Canada, Joanna Fraser, H T. Kunelius Apr 2025

Performance Of White Clover Cultivars In Mixtures With Orchardgrass In Atlantic Canada, Joanna Fraser, H T. Kunelius

IGC Proceedings (1977-2023)

The climate in the Atlantic Provinces of Canada is ideally suited to pasture production, with up to seven months of grow­ing season in some areas. Moreover, many of the soils are too shallow to support deep-rooted and highly valued forages such as alfalfa (Medicago sativa L.) and corn (Zea mays L.). How­ever, the main limiting factor to pasture production occurs in spring where there are frequent freeze-thaw cycles, which reduce the dependability of snow cover for insulation, and this results in winter injury (Dzikowski et al., 1984). The interest in white clover (Trifolium repens L.) as a …


Comparison Of Ryegrass-White Clover And Competitive Interactions In New Zealand And Wales, W Harris, I Rhodes Apr 2025

Comparison Of Ryegrass-White Clover And Competitive Interactions In New Zealand And Wales, W Harris, I Rhodes

IGC Proceedings (1977-2023)

New Zealand and Wales have temperate climates suitable for ryegrass (Lolium species) and white clover (Trifolium repens) pasture. However, pasture management in New Zealand and Wales in fundamentally different. New Zealand pastures are grazed all year, whereas in Wales pastures are mostly not grazed in winter. Moreover New Zealand pastures mostly rely on nitrogen fixed by legumes, whereas nitrogen fertiliser is com­monly applied to Welsh pastures. To consider the basis of differences of pasture management in New Zealand and Wales, data from field experiments at Aberystwyth, Wales (Lat. 52°25'N) and Palmerston North, New Zealand (Lat. 40°20'S) are …


Forage Contribution Of Overseeded Cool-Season Clovers, G D. Mooso Apr 2025

Forage Contribution Of Overseeded Cool-Season Clovers, G D. Mooso

IGC Proceedings (1977-2023)

Warm-season perennial grasses are the foundation of pasture systems in the southeastern U.S. Though well adapted, these species require significant amounts of nitrogen (N) fertilizers to maintain forage production. Nitrogen fertilizers are widely used to improve the yield and quality of grass pastures because it was less expensive and easier to manage than grass-legume mixtures. Cool-season clovers overseeded into dormant peren­nial warm-season swards offer a practical method to extend the grazing season and improve forage quality while capitalizing on the ability of inoculated clovers to supply nitrogen to pro­duction systems thus decreasing production costs (Burton, 1976 ; Hoveland et al., …


Effect Of Irrigation On Vegetation Succession And Forage Regerneration, Fu Jing-Yan Apr 2025

Effect Of Irrigation On Vegetation Succession And Forage Regerneration, Fu Jing-Yan

IGC Proceedings (1977-2023)

No abstract provided.


Reponse Du Brome Cathartique A L’Irrigation Premiers Resultats, C Longueval Apr 2025

Reponse Du Brome Cathartique A L’Irrigation Premiers Resultats, C Longueval

IGC Proceedings (1977-2023)

L'interet de J'irrigation des graminees prairiales est unc ques­tion souvent debattue dans le sud de la France ou la secheresse estivalc ct frequemment automnale limite considerablement la production de fourrage vert durant cette deuxiemc moitie de l'annee. Dans la region toulousaine, les travaux de l'INRA a Tou­louse (Marty et al., 1977) ct de la Compagnic d'Amenagemenl des Coteaux de Gascogne ont montre, pour la fetuque et le dac­tyle notamment, que si !'irrigation pcrrnet de doubler la pro­duction estivale et automnale. le niveau attcint sans restriction hydrique reste globalement rr{odcstc puisque inferieur a 5 t/ha M.S. a partir du debut de …


Drought Stress And Alfalfa Production In A Mediterranean Environment, T Kipnis, I Vaisman, I Granoth Apr 2025

Drought Stress And Alfalfa Production In A Mediterranean Environment, T Kipnis, I Vaisman, I Granoth

IGC Proceedings (1977-2023)

Many experimental results have shown a close relationship between total dry matter (DM) yield of alfalfa and annual evapotranspiration (ET). However, this relationship may differ from harvest to harvest (Metochis and Orphanos, 1981), indicating that water use efficiency (WUE) may vary during the growing season, particulary as it is adversely affected by high temperature (Sammis, 1981). Water for irrigating alfalfa is often scarce during the dry Mediterranean summer in Israel. Under such conditions, water is withheld for approximately two months, at a relatively advanced stage of maturity, and the crop is allowed to go to seed, after which irrigation is …


On The Cultivation And Utilization Of Floret Silvergrass (Miscanthus Floridulus) In The Southern Area Of China, Zhu Bangchang Apr 2025

On The Cultivation And Utilization Of Floret Silvergrass (Miscanthus Floridulus) In The Southern Area Of China, Zhu Bangchang

IGC Proceedings (1977-2023)

The plant genus Miscanthus (silvergrass) includes eight species and one variety in China. In the tropical and subtropi­cal area of south China, the silvergrass distributed widely includes the following seven species : Floret silvergrass ( Miscanthus floridulus), Chinese silvergrass ( M. sinensis), Sugary silvergrass ( M. sacchariflorus), Short-hair silvergrass ( M. brevipilus j, Eulalia silver grass ( M. eulalioides), Szechuan silvcrgrass ( M. szechuanensis), Nepal silvergrass ( M. nepalen�� sis). One of them, Floret silvergrass, is the widest in distri­bution and the highest in economical value, and plays a most important role in …


Continuous Machine Line For Grassland Management On Slopes In Czechoslovakia, L Gonda, S Likavsky Apr 2025

Continuous Machine Line For Grassland Management On Slopes In Czechoslovakia, L Gonda, S Likavsky

IGC Proceedings (1977-2023)

Permanent grass covers in Czechoslovakia are to a great extent spread in sloping and rolling countryside. From the total area presenting 1,672 thousand hectares, 240 thousand ha are stretched on slopes with a gradient of 16 to 22 degrees. Research has shown that from 35 to 48 per cent of these pieces of land arc of size less than 10 ha and there are 75 per cent of intensive pastures with size smaller than 6 ha in typical moun­tainous regions of Czechoslovakia. Mechanization of grass picking on slopes is effected by speci­fic features predetermined by geographical conditions and requirements of …


Studies On Irrigated Tropical Forage Legumes In Sudan, M.A M. Khair Apr 2025

Studies On Irrigated Tropical Forage Legumes In Sudan, M.A M. Khair

IGC Proceedings (1977-2023)

The drought which had struck Sudan in the last few years had necessitated the introduction of the livestock within the farming systems of the irrigated schemes. This implies growing of enough forages in these irrigated schemes. Lablab, Lablab purpureus, clitoria, Clitoria ternatea and phi­lipesara, Phaseolus trilobus are the most commonly grown for­age legume in the Sudan. Information pertaining to the agronomy of these forages are limited in the Sudan. In this report, two ongoing experiments concerning the agronomy of these legumes are discussed. The main objective of exper­iment I was to study the interactive effects of seed rates and cutting …


Monitoring Annual Medicago Ley Pastures For Management Decisions, P G. Tow Apr 2025

Monitoring Annual Medicago Ley Pastures For Management Decisions, P G. Tow

IGC Proceedings (1977-2023)

The Ley Farming System of southern Australia uses a rotation of cereal and pasture comprising annual Medicago (medic) or Trifolium (clover) species. Pastures regenerate in autumn from the permeable fraclion of seed reserves. For M. truncatula cv. Jemalong barrel medic, this is about 10 % annu­ally (Crawford, 1970). In a survey of medic persistence in South Australia, Carter (1982) found that medic seed in the top 5 cm soil was highly correlated with plant density and production potential in the following year. Seed reserves associated with 400-500 plants/m2 were classed as 'good' in commercial practice, but such cases were uncommon, …


Factors Affecting The Productivity Of Elephant Grass, G.E D. Tiley Apr 2025

Factors Affecting The Productivity Of Elephant Grass, G.E D. Tiley

IGC Proceedings (1977-2023)

Elephant grass (Pennisetum purpureum Schumach) is a highly productive and palatable fodder which is widely grown in the tropics (Bogdan, 1977). Optimum utilisation of its production potential is, however, limited by management factors which are associated with plant form and growth habit (Horrell and Tiley, 1970). These factors were studied in a series of trials at Kawanda Research Station, Kampala, Uganda (0°27'N, 32°30'E). A summary of the princi­ pal results is given.