Agronomy and Crop Sciences Commons^™

Breeding Centrosema Pubescens Better Adapted To Acid Infertile Soils Of South America, E M. Hutton

IGC Proceedings (1977-2023)

Centrosema pubescen, Benth. {centro) in tropical South America depends upon the development of lines with increased tolerance to high acidity and aluminum (Al). This study classified levels of acid tolerance among Centrosema introduc­tions and crosses of promising introductions. Initially, greenhouse and field evaluations in Carimagua oxisol (pH 4.5, 90% Al saturation) were used. Introductions of C. schottii and C. pascuorom died, while most C. virginianum and C. Uutifolium and a few C. pubescens had low acid tolerance. Most C. pubescens introductions had medium acid tolerance, whereas C. macrocarpum and C. schiedanum were highly acid tolerant. The degree of acid …

Comparison Of Italian Ryegrass And Meadow Fescue With F2, F3, F4 Hybrids Of Both Grass Species, H Kaltofen, E Wojahn

IGC Proceedings (1977-2023)

In forage-grass breeding there is an increasing interest in hybrids of Italian ryegrass (Lolium multiflorum Lam.) and meadow fescue (Festuca pratensis Huds.). The objective of this study was to investigate some agronomic properties of such Festulolium hybrids with special reference to the question of whether these hybrids change from one generation to the next. In a pot experiment with four levels of nitrogen fertilization, Italian ryegrass and meadow fescue as well as F2, F3, and F4 hybrids of the two grass species were examined for 2 years. In each year four cuts were taken. All the F2, F3, …

Effective Selection For Tolerance To Grass-Killing Herbicides In Perennial Ryegrass (Lolium Perenne L.), C E. Wright, J S. Faulkner

IGC Proceedings (1977-2023)

The aim of grassland reseeding is to establish a high-quality sward of improved herbage cultivars. To obtain the maximum value from the improved sward, weed invasion should be prevented. Herbicides are the main tool available. There are many herbicides for selectively controlling dicotyledonous, but not graminaceous, weeds. The control of graminaceous weeds would be possible in swards of grass cultivars selected for tolerance to grass-killing herbicides. Two cycles of recurrent selection for glyphosate tolerance in Lolium perenne L. were carried out by spraying large seedling populations with critical dosages in the greenhouse and intercrossing the survivors. It was found that …

Selection For Specific Leaf Weight In Reed Canarygrass And Its Effects On The Plant, I T. Carlson, D K. Christensen, R B. Pearce

IGC Proceedings (1977-2023)

Specific leaf weight (SL W, dry weight/unit leaf area) may serve as a selection criterion for forage yield through a positive rela• tionship with photosynthesis. Two cycles of phenotypic selection for high and low SLW were conducted in reed canarygrass (Phalaris anmdinacea L.) to investigate direct and correlated responses, particularly those related to yield and quality of forage. In a space-planted test, average direct responses from two cycles of selection for high and low SLW were 23% and 19%, respectively. Significant correlated responses were obtained for ten traits. Compared with the low-SLW cycle-2 population, the high SLW cycle-2 population averaged …

Value Of White Sweet Lupin In Production Of Protein Fodder And Feeding Of Animals, O Saric, I Ramosevac

IGC Proceedings (1977-2023)

The potential of white sweet lupin (Lupinus albus L.) as a grain or forage feed for livestock was investigated in a series of ex­periments. Grain yield of lupin was greater than or equal to that of soybeans (Glycine max [L.] Merrill) in most evaluations. The quality of lupin seed compared favorably with that of soybean meal and fishmeal. Lupin is capable of producing large amounts of forage in a short period, making it a good prospect for forage production in regions that have a short growing season.

Genetic Variability For Morphological And Agronomic Characters In Desmodium Uncinatum (Jacq.) D.C. And D. Intortum (Mill.) Urb., E.M P. Oliveira, P S. Martins, A B. Cruz

IGC Proceedings (1977-2023)

Objectives of this research were to study the performance of eight populations of D. unicinatum and ten populations of D. intortum, with relation to morphological and agronomic characters to estimate the genetic variation between populations and between plants within populations, and to estimate genetic and phenotypic parameters for these characters.

White Clover: An Olde Crop With A Promising Future, P B. Gibson, W E. Knight, G W. Barnett, W A. Cope, J D. Miller

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) is a widely adapted, important forage legume for grazing in the U.S. The palatability and quality of the forage, the wide adaptation of the plants to growth in different climates and under various grazing conditions and the role it plays in supplying nitrogen to pastures make white clover our finest pasture legume. The use of adapted white clover cultivars should result in large economic gains to the livestock industry in the U.S .A. Beef and dairy farmers would profit from reduced need for nitrogen fertilizer, an extended grazing season, increased forage pro­duction and quality, better …

Performance And Variability Of Agronomic Characters In Populations Of Stylosanthes Guianensis (Aubl.) Sw., P S. Martins, N A. Vello

IGC Proceedings (1977-2023)

Stylosanthes guianens-is (Aubl.) Sw. shows wide variations in morphological and physiological characteristics, and basic infor­mation on genetic variability is needed for future breeding programs. The objectives of this paper were to evaluate 25 native Brazilian populations of S. guianensis for forage characteristics · • ;10,d • to estimate genetic and phenotypic parameters for these characters. The experiment was conducted in a duplicated 5 x 5 balanced lattice design with plots that contained 4 individuals spaced on 2-m centers. The following characters were evaluated after the beginning of flowering period: days to flowering (DF), mean diameter (MD), basal area (BA), growth …

Rhizoma Peanut: Perennial Warm-Season Forage Legume, G M. Prine

IGC Proceedings (1977-2023)

Rhizoma peanut is the common name given species in section Rhizomatosae of the genus Arachis. Florigraze rhizoma peanut (A. glabrata Benth.) has been released as a cultivar by the Florida agricultural experiment stations and the USDA Soil Conserva­tion Service. Florigraze is adapted to the well-drained soils of Florida and the warm humid tropics and subtropics around the world. Rhizoma peanuts are propagated by rhizomes, which in Florida are best planted during winter. The slowness of coverage during early establishment is the biggest shortcoming of rhizoma peanuts. If they are established first, rhizoma peanuts will grow well in mixture with bermudagrass …

Hedysarum Mongolicum Turcz.: An Important Protein Resource Legume On Dry Sandy Land, Li Min, A W. Hovin

IGC Proceedings (1977-2023)

In searching for plants that can both increase the protein production and improve the sandy-soil conservation of the grassland in the arid, windy regions of North China, so far, from among many native plants, we have identified Hedysarum mongolicum Turcz. as the best species to fulfill our dual purposes. We investigated its distribution, planted its native seeds in the Maowusu desert, and studied it under its native and cultivated growing conditions from 1957 to 1964. Chinese farmers call this perennial subbrush legume of the sweetvetcb genus "Yang Cai," meaning "sheep like to eat." It can thrive in the stable or …

Adaptation And Utilization Of Three Legume In China, Huang Wenhui

IGC Proceedings (1977-2023)

China is a vast territory with extremely varied climates, soil, and topography, and it is very rich in pasture grass resources. The main legumes for forage are Alfalfa (Medicago sativa L.), yellow alfalfa (Medicago folcata L.) and shadawang (Astragalis adsurgent Pall.)

Preliminary Evaluation Of Legume Germ Plasm In The Cerrados Of Brazil, D Thomas, R P. De Andrade

IGC Proceedings (1977-2023)

In 1978 an evaluation program was initiated to select legumes that (1) grow and produce seed on acid soils under aluminum and water stress, (2) persist under grazing, and (3) tolerate pests and diseases. The work is being conducted at the Cerrados Agricultural Research Center, near Brasilia, at lat 15°S and altitude 1,000 to 1, 100 m . Annual rainfall is 1,500 mm, mostly distributed in a 6-month wet season, and mean annual temperature is 21°C. Nine hundred legume accessions from thirteen genera have now been established as spaced plants on the 2 major soil types of the region. The …

Genetics And Utilization Of Apomixis For The Improvement Of Guineagrass (Panicum Maximum Jacq.), Y H. Savidan

IGC Proceedings (1977-2023)

Natural polymorphism in guineagrass (Panicum maximumjacq.) has been stabilized in tetraploid biotypes by apomixis. Sex­ual diploids were found in East African populations. Our objective was to determine whether apomixis could be related with a simple genetic background and manipulated in an improvement program. Apomicts of guineagrass are characterized by a 4-nucleate embryo sac structure, and this trait was used in genetical analyses to differentiate apomictic from sexual hybrids. Progeny tests were also conducted as controls. Ten different types of progenies were analyzed: tetraploid sexual (from colchicine treatment of diploids) x apomictic F1 hybrids; selfed and backcrossed progenies of sexual F1 …

Breeding Challenges In Apomictic Warm-Season Grasses, E C. Bashaw, P W. Voigt, B L. Burson

IGC Proceedings (1977-2023)

Efforts to breed apomictic grasses met with little success in the past, but results of more recent research show significant progress with some species and new prospects for improving apomicts. Early research uncovered the cytological basis for apospory and diplospory, found the common apomictic mechanisms in grasses, and showed that apomixis is transmitted from pannt to offspring. Discovery of sexual or partially sexual (facultative apomicts) plants in several species formerly considered obligate apomicts allowed for hybridization and genetic studies. Results of subsequent research confirmed inheritance of apomixis, and data from the more conclusive studies indicate that method of reproduction …

European Corn Borer Management In Field Corn, Igor Sulzbacher Schardong, Francis Reay-Jones

Agronomic Crops

In the past, European Corn Borer (ECB) was considered a billion-dollar pest. Bt corn was first released in 1996 and its widely adoption reduced ECB populations and economic importance. Resistance to some Bt toxins was detected in Canada, representing a possible threat to corn production. In this paper, we reviewed potential management tactics for ECB in corn.

Evaluating Soil Health And Crop Yield In Louisiana Agricultural Systems: Impacts Of Best Management Practices And Prediction Models, Hector J. Mendoza Lagos

LSU Doctoral Dissertations

The adoption of conservation management practices is critical for improving soil health, enhancing nutrient use efficiency, and sustaining crop productivity in row crop systems in Louisiana. This study evaluated the role of conservation agronomic practices, soil biochemical indicators, and machine learning predictive models to improve soil nutrient dynamics, soil health indicators, microbial communities (MC), and crop productivity on a corn (Zea mays L.) research plot scale and in a commercial forty-hectare cotton (Gassypium hirsutum L.)-corn-soybean (Glycine max L.) rotation system in northeast Louisiana. The objectives of the study were to evaluate soil nutrient dynamics and MCs under …

Double Cropping Fodder Maize: Broome 2022, Carla Milazzo, Christopher Ham, Geoff Moore

Grain and other field crops research reports

• While it is logistically feasible to grow and harvest two short-season maize crops during the dry season in the West Kimberley, growing a single crop with high yield potential is a more efficient use of machinery, labour and inputs.
• Total biomass yield from a double cropping trial east of Broome generated 20.8t/ha dry matter and 59.7t/ha of silage over a seven-month period but this did not exceed the yield achieved from growing a single crop with a longer-season phenology and best practice agronomy.
• Plant population density was highly correlated with yield, underscoring the importance of achieving the target plant population …

Nitrogen-Use Efficiency Of Irrigated Rhodes Grass In Northern Wa, Carla Milazzo, Christopher Ham, Geoff Moore

Grain and other field crops research reports

Cultivation of irrigated fodder and forage crops to intensify northern beef production in the west Kimberley and Pilbara has seen significant private investment over the past decade. To support this growing investment, the Department of Primary Industries and Regional Development (DPIRD) carried out replicated, randomised trials on irrigated Rhodes grass near Broome.

High nitrogen (N) inputs are required for subtropical grasses to achieve annual growth rates of up to 40 t DM/ha and there is growing scrutiny of these systems to prevent nutrient losses to groundwater and downstream ecosystems. The research aimed to establish N (urea) response curves to five …

Evaluation Of Subtropical And Tropical Perennial Grasses For Irrigated Fodder In Northern Wa, Carla Milazzo, Samuel Crouch, Christopher Ham, Geoff Moore

Grain and other field crops research reports

• Under irrigation, varieties of Rhodes grass (Chloris gayana) and panic grass (Megathyrsus maximus) grew more than 110 kg/ha dry matter per day, when averaged over a year, equal to more than 40 t/ha dry matter annually. Digit grasses (Digitaria spp.) were significantly lower yielding.
• Daily growth rates were affected by seasonal conditions and ranged from 60–90 kg/ha in Barrgana season (June–August) to 110–170 kg/ha in Wirlburu-Laja (September–November). Panic grass was slightly more sensitive to cool temperatures than Rhodes grass.
• Subtropical grasses outperformed tropical grass varieties such as Jarra grass, which had very low growth during the cool months (June–July).
• Crude …

Fodder Maize Variety Trial: Broome 2021, Carla Milazzo, Samuel Crouch, Christopher Ham, Geoff Moore

Grain and other field crops research reports

• High yielding, highly digestible maize can be produced under irrigation on Pindan sands in northern Western Australia.
• Using high inputs, the biomass and digestibility of all trialled varieties equalled or exceeded varieties used in well-established maize growing regions of Australia.
• Eleven hybrid maize varieties were trialled near Broome. The average dry matter yield of all trialled varieties was 24t/ha at 10.5MJ/kg of dry matter.
• The impact of fall armyworm on yield was successfully reduced by using integrated pest management combining NPV virus (nucleopolyhedrovirus) with strategic insecticide applications.