Plant Pathology Commons^™

Diversity In Macroptilium Atropurpureum (Dc.) Urb., A E. Kretschmer Jr, R M. Sonoda, R C. Bullock, G H. Snyder, T C. Wilson, R Reid, J B. Brolman

IGC Proceedings (1977-2023)

A replicated experiment was used to determine the diversity of 77 accessions of Mexican Macroptilium atropurpurem compared with cv. 'Siratro'. Siratro yielded less than the mean of the 5 highest yielding entries in 3 of 6 harvests; it flowered earlier and more consistently between harvests than many other entries. Siratro rust incidence was relatively very high while mildew and Rhizoctonia incidence was relatively very low when compared to Siratro. Mite damage was also relatively low for Siratro. There was great diversity among the populations studied with regards to the attributes studied. Several accessions had more desireable attributes than Siratro. More …

Centrosem Macrocarpum Benth., A Promising Tropical Forage Legume For Acid Soils, R Schultze-Kraft, G Keller-Grein, J Belalcazar, G Benavides

IGC Proceedings (1977-2023)

A hitherto agronomically little-known Centrosema species is described in terms of its morphology, natural distribution, and potential as a forage plant. C. macrocarpum is closely related to C. pubescens, the principal morphological difference being the considerably larger size of C. macrocarpum plant organs. Its natural distribution covers a wide range of latitudes and climatic and edaphic conditions in tropical America. Ecotypes from collection sites north of the equator have proven to be well adapted to acid soils. In a small-plot cutting trial conducted in Colombia on an acid Ultisol (pH 4.1, 89% aluminium saturation), C. macrocarpum ecotypes considerably outyielded …

Preliminary Observations With Accessions Of Stylosanthes Guianensis Ssp. Guianensis Var. Pauciflora In Brazil, D Thomas, R P. De Andrade, J Lenne

IGC Proceedings (1977-2023)

Forty-two accessions of the morphologically distinct Stylosanthes guiansis ssp. guianensis var. pauciflora collected in Brazil and Venezuela were evaluated for their adaptation to environment in the tropical savanna region of central Brazil. The study was conducted on an Oxisol at the Centro de Pesquisa Agropecuaria dos Cerrados (CPAC), 35 km from Brasilia at latitude 15° 36' S. Results showed that was marked variation in plant yield and, as a group, Brazilian accessions produced more dry matter than Venezuelan accessions. Anthracnose resistance and digestible dry matter content were also markedly higher in the accessions from Brazil. No significant differences in …

The Persistence Of Stylosanthes In Florida, A Review, John B. Brolmann

IGC Proceedings (1977-2023)

The importance of introducing tropical legumes to improve pastures in South Florida is well recognized. Little is known about the persistence of these legumes. The purpose of this study was to evaluate the survival of several Stylosanthes species in pure stands or grass mixtures. Stands of Stylosanthes were evaluated for spread, vigor and persistence. S. guianensis and S. scabra, established in 1971 survived the longest. These stands regenerated each year from seeds. Sterile off-types of S. guianensis showed greater survival ability than most introduced species and acted as Management practices and favorable environmental conditions appear to be of prime importance …

Problems Experienced With Forage Legumes In A Tropical Savanna Environment In Brazil, D Thomas, R P. De Andrade, B Grof

IGC Proceedings (1977-2023)

Since 1978 some 1700 legumes from 17 genera and 50 species have been evaluated on soils at the Centro de Pesquisa Agropecuaria dos Cerrados (CPAC) at latitude 15° 36' S in the tropical savanna region of Brazil. In characterizing the germplasm a number of problems have become evident. Plant dise4ses are primary limiting factors. Species of Stylosanthes are attacked by anthracnose ( Colletotrichum gloeosporioides) whilst other diseases affecting species of Centrosema, Desmodium and Zornia are described. Accessions collected in the acid soils with a high aluminium saturation are well adapted to these conditions. However, species such as Leucaena Jeucocephala from …

Summer Forage Legume Introduction In Louisiana, A M. Thro, C C. Shock

IGC Proceedings (1977-2023)

Climate in Louisiana is influenced by tropical air masses in summer and alternately by tropical and continental air masses in winter. From northwest to southeast, the number of frost-free growing days increases from 230 to 350. Rainfall increase from 1200 mm to 1500 mm and is evenly distributed winter through summer with a generally drier fall. Livestock production is an important economic activity throughout the state. Animal performance declines from July through November in spite of adequate availability of perennial grass forage. A summer-growing forage legume is sought that will persist in perennial grass pastures and provide a more easily …

Bio-Agronomic Evaluation Of Lolium Multiflorum Populations Collected In Irrigated Plains Of Northern Italy, P Rotili, G Gnocchi, C Scotti, A Sererna

IGC Proceedings (1977-2023)

In the irrigated plains of Lombardy the continuous elimination of the permanent meadows and their replacement with the maize imposes the collection and conservation of Lolium multiflorum. Twenty seven populations, collected in the Milano-Lodi-Cremaarea, were evaluated in greenhouse, in concrete boxes 150 cm long, 40 cm high and 25 cm wide. Distance between the plants on the rows cm 2.5 (density 350 plants/m2). Dry forage yield, earliness and mortality were studied. Concerning dry forage yield there is not difference between the collected populations. On the contrary, a significant difference was observed between the whole set of collected populations and the …

Seasonal Growth Of Mediterranean Tall Fescue Populations, Y Ueyama, S Sato, K Nakajima

IGC Proceedings (1977-2023)

Thirteen Mediterranean populations of tall fescue (Festuca arundinacea Schreb.) including four cultivars originated from the same region with three check cultivars were evaluated for several characters relating to seasonal productivity. Mediterranean populations were depressed under hot and humid summer conditions, and were not restored until December. However, these entries showed good growth and little leaf burning in winter and early spring. Three hundred and fifty two individuals were screened with scores of vigor. Data of the individuals were subjected to principal component analysis. The first and second components were closely correlated to the variables relating to growth in summer and …

A Study Of Phenology, Herbage Yield And Crude Protein Content Of Native Ecotypes Of Red Bromegrasses (Bromus Tomentellus Boiss.) Of Iran, B Peymani-Fard

IGC Proceedings (1977-2023)

This research was conducted on ten ecotypes of red bromegrasses of Iran at Homand Range Experiment Station, near Damavand, Iran to asses: (a) the differences in phenological characteristics, (b) to evaluate differences in herbage yield, and (c) determine the crude protein percentage Parameters measured include duration of vegetative, heading, maturity stages, herbage yields, and crude protein. Variation in vegetative growth, heading and seed maturity stages among the ecotypes under study was very small

Therefore, there are no prefences in selection of a specific ecotype from the standpoint of utilization and harvesting time. There was a great fluctuation in annual herbage …

Scope For Breeding Miscanthus Sinensis Anderss. As Forage Crop, S Hoshino

IGC Proceedings (1977-2023)

Miscanthus sinensis Anderss., an indigenous summer growing tussock grass species, has been utilized traditionally in Japan for many centuries as bulk herbage to feed livestock, material for thatching roof and snowshed etc, but this species does not survive well under frequent cutting. Experiments were conducted to select more vigorous strains among fifty clones collected from various meadows throughout Niigata Prefecture in 1967. Several clones were detected for better regrowth performance and their dry matter productions were compared for four years under three cuttings a year with fertilizer application scheme. Dry matter productions of the selected clones were comparable to those …

Performance Of Nine Mid-East Alfalfa Ecotypes And Seventeen Introduced Cultivars In Saudi Arabia, V L. Marble, A C. Wilton, A A. Cook

IGC Proceedings (1977-2023)

A program designed to determine the productivity of nine middle eastern (ME) alfalfa (Medicago sativa L.) ecotypes and 17 alfalfa cultivars from California, Australia, and New Zealand, is described. Selected harvests, representing performance characteristics during different seasons of the year, and the 13 cuts taken between March 31, 1983 and February 15, 1984 indicate that all but one of the ME entries were higher yielding (P = < .05) than all but one western alfalfa. By the 17th harvest taken May 28, 1984, three ecotypes from Egypt were superior (P = < .05) to all other entries including those commonly used in Saudi Arabia. In orthogonal comparisons, the mean of 17 western alfalfas was inferior to the mean of nine mideast ecotypes by the third and all subsequent cuts through the 17th. Two Saudi Arabian check entries, Hasawi I and Hasawi II, were similar yielding throughout the 17 harvests, but were significantly inferior to the other seven ME ecotypes in orthogonal comparisons between the two groups. The annual productivity potential of superior entries exceeded 38 metric tons per hectare (T/ha) of dry matter. Seasonal distribution of yield varied among entries with most ME entries significantly superior to most western entries in all four seasons. Middle eastern ecotypes had greater (P = < .05) height at cutting than western alfalfas. As a group they flowered earlier, and showed lower incidence of enation virus. Based on 17 harvests over an 18-month period, middle eastern ecotypes were better adapted to growing conditions in central Saudi Arabia than introduced western cultivars.

Mediterranean-Germplasm Trefoils In The Southeastern Usa Piedmont, C S. Hoveland, S L. Fales

IGC Proceedings (1977-2023)

Experimental birdsfoot trefoil (Lotus corniculatus) cultivars, selected from Mediterranean germplasm, were compared with northern trefoils in monoculture and in association with grasses to determine productivity and persistence in north Georgia where northern trefoils have not been successful. Productivity and forage quality of one trefoil was studied under four frequencies of defoliation. Mediterranean trefoils had higher total and earlier spring production, better stand persistence, and seedling vigor than a northern cultivar. The yield advantage of Mediterranean trefoils occurred in monoculture and when grown in association with tall fescue (Festuca arundinaceae) or orchardgrass (Dactylis glomerata). Maximum yields …

Annual Legumes For Integrating Rainfed Crop And Livestock Production, A E. Osman, N Nersoyan

IGC Proceedings (1977-2023)

A program aimed at integrating rainfed crop and livestock production in West Asia and North Africa is described, where the objective is to introduce pasture and forage legumes in place of existing fallows. Research has identified that suitable species of Medicago, Pisum and Vicia are well adapted to the climatic conditions of North Syria. This article describes studies evaluating mixtures of common vetch (Vicia sativa) and forage peas (Pisum sativum) with barley, triticale and oats for hay production. Mixtures including the two legumes were also evaluated for early grazing by sheep followed by hay making in …

Fall Panicum (Panicum Dichotomiflorum Michx.) In Japan, K Ohta, M Ochi

IGC Proceedings (1977-2023)

Fall panicum (Panicum dichotomiflorum Michx.), which is a naturalized plants, is tolerant to high soil moisture and is highly productive. For the purpose of using it as a forage suitable to high soil moisture conditions, such as paddy fields, fall panicum strains were collected from various districts in Japan. The present experiment was undertaken to clarify the characteristics and the distribution of fall panicum. In order to define the groupings by compound characteristics, multivariate analysis (principal component and cluster analysis) was performed. It was concluded that fall panicum strains could be classified into five groups and their distribution could …

Selection For Seed Production And Dry Season Forage Yield In Panicum Maimum Germplasm, L Jank, Y H. Savidan

IGC Proceedings (1977-2023)

Panicum maximum cv. 'Coloniiio' is the most popular tropical forage grass in terms of cattle finishing in Brazil. It is, however, slowly being substituted by other species, because of its high demands for nutrients and poor dry season growth. The National Beef Cattle Research Center of EMBRAPA at Campo Grande, Mato Grosso do Sul, has underway a P. maximum breeding program, with the objectives of selecting cultivars which while maintaining the good qualities of the 'Coloniiio', are more drought-resistant and adapted either to the traditional fertile soils of 'Coloniiio', or to weak cerrado (savanna) soils. Preliminary results on seed production …

Preliminary Evaluation Of Panicum Maximum Germplasm In Brazil: An International Agronomy Research Program, Y H. Savidan, L Jank, F.H.D De Souza, A Boock

IGC Proceedings (1977-2023)

Following former recommendations to leave traditional schemes of simultaneous evaluation of several species, and extensive program has been initiated as a result of an international agreement between French and Brazilian research organizations, to evaluate one single tropical forage grass species with wide genetic diversity. A field experiment was designed for preliminary evaluation of 400 accessions of Panicum maximum at two levels of soil fertility. Emphasis is placed on a fixed-interval cutting regime, seed production, and detailed morphological characterization of promising accessions. A list of the morphological descriptors is presented. Selected accessions will enter further phases of evaluation under grazing and …

Collection Of Germplasm Of Desmodium And Related Genera In Indonesia, K L. Mehra

IGC Proceedings (1977-2023)

17 species of Desmodium and 5 species of the related genera were collected from the islands of Sulawesi, Java, Timor and Sumba. The collection sites differed in rainfall, altitude, soil pH, vegetation and other eco-geographic characteristics. Several samples with good agronomic potential were collected from acid infertile soils. The collections differed in growth habit, biomass production, leafiness, seed setting and adaptation to problem soils. Promising collections for use in crop improvement programme were identified.

Collecting Germplasm Of Desmodium And Puerarua Phaseoloides In Thailand And Peninsular Malaysia, S Pattanavibul, R Schultze-Kraft

IGC Proceedings (1977-2023)

A collaborative program to collect native legume germplasm in Thailand and peninsular Malaysia is described. Three collection expeditions were carried out in 1979, 1982, and 1984 with particular emphasis on broadening the genetic bases of Desmodium species and Pueraria phaseoloides. In total, 593 samples were collected: 60% were species of Desmodium and its allied genera Dendrolobium, Dicerma, Hegnera, Phyllodium, and Tadehagi, 12% were P. phaseoloides material and the remaining 28% were germplasm of other genera such as Abrus, Alysicarpus, Atylosia,Dunbaria, Flemingia, and Uraria. The importance of increased genetic variability within the species D. ovalifolium and P. phaseo/oides …

Development Of An International Collection Of Tropical Forage Germplasm For Acid Soils, R Schultze-Kraft

IGC Proceedings (1977-2023)

SUMMARY A Program conducted by the Centro Internacional de Agricultura Tropical ( CIA T) to develop a collection of forage plant germplasm resources for tropical pasture research in acid, infertile soil areas is described. After an initial 5-year stage of preliminary work in germplasm collection and introduction, 28 major expeditions to collect native germplasm of tropical forage species were carried out in 10 countries on 3 continents, principally in regions with acid soils of low fertility during 1977 to 1984. Emphasis has been on legumes,mainly Centrosema, Desmodium, Stylosanthes, and Zornia, in tropical America, andDesmodium, its allied genera, andPueraria in Southeast …

A Global Plan For Forage Genetic Resources, W. Ellis Davies

IGC Proceedings (1977-2023)

Initially the Board's work gave priority to major crops but latterly more attention has been given to forage plants. Forages now have a high priority in the following IBPGR regions: Mediterranean, Southwest Asia, Central Asia, Southeast Asia, East Asia, Central America, the Andean region, southern South America and Europe. One major difficulty with forage plants is the large number of genera/ species - numbering into thousands which have some forage value. For practical operational reasons the world forage genetic resources have been con­sidered under headings (a) Tropical and sub-tropical areas (b) Mediterranean and adjacent semi-arid/areas and (c) Temperate areas. Because …

Modification Des Facteurs Biotiques Par La Presence D'Arbres En Region Mediterraneenne Francaise: Effets Sur La Production Herbagere, B Msika, M Etienne

IGC Proceedings (1977-2023)

La region mediterraneenne franc;:aise se caracterise par !'im­portance de son territoire forestier qui, bien que souvent degrade, comporte une grande variete d'especes arborees. II s'agit principalement de peuplements forestiers spontanes geres en taillis ou de reboisements en resineux. Abandonnes depuis les annees 40, ces espaces sont devenus totalement improductifs et posent des problemes de protection contre Jes incendies ou de gestion sylvicole adaptee. Dans le contexte actuel, et dans ce type de milieu, la diversification des productions semble etre une voie interessante a creuser. Les amenagements sylvopastoraux pourraient done constituer une alternative interessante ; encore faut-il que Jes conditions opti­males …

The Dynamics Of Daily Area And Depth Of Grazing And Herbage Intake Of Cows In A Five Day Paddock System, M H. Wade, J L. Peyraud, G Lemaire, E A. Comeron

IGC Proceedings (1977-2023)

Optimisation of animal production per unit area results in a penalty to individual animal production and herbage intake. The objective of the present study was to examine the dynamic changes in a grass sward in relation to declining production and herbage intake in five day paddocks grazed by dairy cows. The study formed part of a larger project to examine the effects of stocking rate and grazing method upon milk production and herbage intake that is reported by Peyraud et al. (1989).

The Relationship Of Herbage Intake Of Cattle To Herbage Mass, And Its Utilization On Rotationally Grazed Pasture, T Okajima, K Sawada, H Noriike, H Yokota

IGC Proceedings (1977-2023)

In the central part of Honshu island in Japan, seasonal vari­ation of herbage mass is also large (Okajima et al., 1985). So, when the grazing managements, i.e. stocking rate, grazing intensity etc., were not appropriate, part of herbage produced was lost through standing dead and litter, or grazing cattle lose their body weight. Sward characteristics affect the grazing behaviour of cattle (Jamieson and Hodgson, 1979), and then affect the herbage production and utilization. Relative herbage intake of cows was related to sward height (Baker et al., 1981). So, sward height was used as the indicator of the grazing management in …

The Effect Of Daily Herbage Allowance On The Ingestive Behavior Of Dairy Cows, M Rogalski, J Kryszak, Z Karzoun

IGC Proceedings (1977-2023)

In conditions of pasture feeding sward selection and con­sumption by grazing animals is strongly influenced by char­acters of herbage (Forbes, 1986). Quantitative and qualitative state of the sward affects its consumption primarily through changes of such elements in animal behaviour as grazing time and number and size of bites (Hodgson, 1982, 1985). Rela­tivelyt much research has been done to investigate the response to the grazed sward of such ruminants as sheep, while the response of cattle, and particularly of dairy cows, has received much less attention (Arnold, 1981 ; Holmes, 1980). This paper presents results of investigations on the effect …

Effect Of Grazing On Pasture Production In South-West Western Australia, K.M S. Curtis, A C. Dunlop, T O. Albertson

IGC Proceedings (1977-2023)

INTRODUCTION With a mediterranean climate in the south-west of Western Australia, pastures are composed of annual species from the genera Trifolium, Hordeum, Lolium, Bromus, Vulpia, Erodium and Artotheca. The length of the growing season ranges from 9 months near the coast to less than 5 months in the eastern wheatbelt. Seven million hectares of pastures are grazed predominantly by Merino sheep (about 33 millions). Stoking rate is the major factor affecting wool production on farm. An increase in stocking rate reduces wool production per sheep.Increasing the stocking rate reduces total pasture growth (Dunlop, et al., 1984) and changes the botanic …

Development Of A General Relationship Between Stocking Rate And Animal Production, J.M Van Heerden, N M. Tainton

IGC Proceedings (1977-2023)

One of the best known mathematical representations of the relationship between stocking rate and individual animal pro­duction, that of Mot (1960), postulated a modified exponential relationship. Subsequent workers, however, derived a linear relationship between stocking rate and production per animal unit, at least at stocking rates beyond a certain minimum value. One of these relationships, that of Jones & Sandland (1974), is widely used in South Africa. The results of grazing trials with sheep on complex grass/legume mixtures in the winter rainfall region of South Africa (van Heerden & Tainton, 1987-1988), however, suggested a degree of non-linearity in this relation­ship. …

Mixed Animal Species Grazing Under Temperate And Semi-Arid Conditions, T Nolan, J Connolly, L M. Guillon, C Sall, K Dieye, K Dieye, H Guerin

IGC Proceedings (1977-2023)

Mixed grazing has been practiced for a long time, under a variety of climatic conditions, combinations of animal species and grazing managements (Nolan and Connolly, 1977). They suggested that although mixed grazing research progress was impeded by difficulties associated with the increased number of variables involved it offered greater opportunity to improve resource use. The purpose of this paper is to present results from recent research carried out under temperate and semi-arid conditions related to individual animal and per unit area outputs, animal/vegetation relationships and complemetary patterns of grazing behavious in relation to more efficient and balanced use of vegetation …

The Influence Of Clothes On The Thermoregulatory Behavior And The Protection Against External Parasites Of Grazing Cattle, M Sakurai, A Yamada

IGC Proceedings (1977-2023)

Under the monsoon climate, maximum temperature showed 34 °C in August and minimum temperature showed - 15 °C in February, total rainfall amounting to 1.700 mm. Through the welfare of the grazing cattle, both hot, rain and frosty environ­ment influence the animal production (Bennett et al., 1984; Done-Currie Jr et al., 1984; Fraser, 1983). In order to improve the welfare of grazing cattle under hot, cold, rain and attacks of the external parasites, the efficiency of cattle clothes were studied.

Comparison Of Energy Budget In Pastures By System Model: Intensively Managed Pasture Vs. Extensively Managed Pasture, M Shiyomi, N Koyama, M Tsuiki, K Ochiai, H Kobayashi, S Shioya, T Ami

IGC Proceedings (1977-2023)

An annual gain of 1 ton cattle body weight per ha was attained in an intensively managed pasture (IMP) of the National Grassland research Institute, NGRI, in 1986. In this experiment the efficiency of solar energy converted into herbage and cattle body was not directly determined although seasonal changes in herbage and animal biomasses were measured. In current report, the energy budget for herbage and cattle body in this pasture was estimated and compared with that in an extensively managed pasture (EMP) using a system model.

Cattle Grazing Of Bahiagrass (Paspalum Notatum Flugge) Sward Canopy As Influenced By Dung Deposition, M Hirata, Y Sugimoto, M Ueno

IGC Proceedings (1977-2023)

It is commonly observed in a grazed pasture that the grazing animal rejects the herbage on and near the dung pat (Marsh and Campling, 1970). However, quantitative information on the dung-induced changes in herbage consumption is very limited. In this study, cattle grazing of the dung-deposited sward canopy is compared with that of the dung-free sward canopy in order to clear the cattle dung effect on the herbage consumption in a bahiagrass pasture.