Plant Biology Commons^™

Improvement Of Shrub-Covered Hill Pasture By Root Raking: Effect Of Aspect, Superphosphate And Time From Sowing On Nitrogen Fixation And Clover Growth, M P. Rolston, J R. Crush, B P. Devantier

IGC Proceedings (1977-2023)

New white clover (Trifolium repens) grass pastures were established on shrub-covered hill slopes cleared by bulldozer root raking, The site included north and south aspects, and plots were individually fenced and grazed with sheep with superphosphate treatments of 1815 or 790 kg/ha (9% P). Nitrogen fixation was assessed over 5 years, with up. to 308 kg N/ha fixed in year I. Nitrogen fixation rates declined with time and were 72% higher on the moister southern aspect, and 33% higher with high superphosphate. Clover production showed similar trends. Nitrogen fixation efficiency (kg N fixed/I clover dry matter) increased from …

Breeding Switchgrass For Improved Animal Performance, K P. Vogel, K J. Moore, A A. Hopkins

IGC Proceedings (1977-2023)

Studies on breeding and evaluating switchgrass (Panicum virgatum L.) for improved animal performance have been conducted for the last 18 years. !ti vitro dry matter digestibility (IVDMD) has been increased 3 8 g/kg after 3 cycles of selection; demonstrating· that IVDMD of switchgrass can be improved using recurrent, phenotypjc selection. Digestibility of plant tillers collected at panicle emergence was an excellent predictor of IVDMD of progeny in pastures or swards during the growing season. Small improvements in IVDMD (20-30 g/kg} significantly improved average daily gains and gains/ha (17-24 %) of beer cattle (Bos taurus) grazing switchgrass. It should …

Fertilizer Policies For Grassland Production In Winter Cold High Country In The South Island New Zealand And Southern China, C C. Boswell, M.J S. Floate

IGC Proceedings (1977-2023)

Fertiliser policies for legume-based pastures on the high plateau of Guizhou province southern China are compared with those for the South Island of New Zealand, Guizhou policy is reduced to a few essentials. Choice of fertiliser is restricted; severe phosphorus deficiency is corrected with locally manufactured fused calcium magnesium phosphate, potassium deficiency with imported potassium sulphate or chloride. A simple recommendation applies for establishment and maintaining production over vast areas and potentially to huge numbers of small farms (3-7 ha). In the South Island high country, fertiliser forms and rates are matched as far as possible to the variety of …

Residual Effects Of Oversowing, Overdrilling, And Herbicide In The Long-Term Control Of Hieracium Pilosella In Otago, New Zealand, G G. Cossens, C C. Boswell

IGC Proceedings (1977-2023)

The mat-forming weed Hieracium pilosella {mouse-eared hawkweed) has become a major problem of tussock grasslands in New Zealand. Thirteen trials investigating methods of hawkweed control were laid down during 1975-80, monitored for 3 years, and subsequently reassessed in 1991. When grazing was excluded hawkweed was reduced from 60 to 3% ground cover within 18 months by topdressing and oversowing or overdrilling legumes; and to 22% by the use of the herbicides, 2,4 D and mecoprop-MCPA-dicamba. With grazing and no further topdressing, these improved lands reverted to hawkweed at a mean rate of 2-3%/year, as did overgrazed unimproved tussock grassland. In …

Rangeland Improvement On Granitic Soils In Uruguay, D F. Risso, D A. Moron

IGC Proceedings (1977-2023)

Granitic soils comprise more than 15% of productive land of the country, Soils are variable, all being deficient in nitrogen and phosphorus, having a moderately low pH, more than 40% being shallow with low levels of organic matter. Livestock production is predominantly developed on range with moderate yield and ample variations (avg. DM/ha/year=3.l t; c.v.=27.6%; winter yield=l2%), Research conducted to improve this situation, evaluated: 1) range P fertilisation during 5 years, which resulted in a small (but significant) yield increase and improved P concentration of forage. 2) P fertilisation and interseeding of legumes through different methods. Largest differences were due …

Use Of Dryland Forage Plants For Improving Semi-Arid And Hawkweed-Affected Land In New Zealand, B J. Wills, J S. Sheppard, J.S C. Begg

IGC Proceedings (1977-2023)

mi-arid climatic conditions affect large areas of New Zealand's South Island east coast and inland basins. A significant area - some 6 million ha - is affected by, or is at risk from, invasion by hawkweeds, mainly Hieracium pilose/la. This plant, along with rabbits, is severely affecting the viability of extensive pastoral grassland farming in New Zealand. Soil erosion, in particular associated with frost heave and wind, is notable in areas associated with both a semi-arid climate and high densities of hawkweeds. The use of dryland pasture plants selected for drought tolerance, frost tolerance and ability to grow under low …

Small-Grain Forage For Winter Pastures, D J. Undersander, D P. Hutchenson

IGC Proceedings (1977-2023)

The paper summarises 2 studies comparing wheal (Triticum aestivum), barley (Horderim vulgare), rye (Triticale secale), and triticale (x Triticoseca/e) for fornge production and animal performance. Wheat, rye and triticale were planted in 10, 20 and 30 cm row spacings and grown over 2 winters in South Carolina. Porage yield from early­October plantings ranged from 2961 to 5000 kg/ha in 1986-87 and from l012 to 3400 kg/ha in 1987-88. Porage yield was highest from rye, most of the forage growth occurring in autumn. Wheat produced forage growth most uniformly throughout autumn and spring. In the …

Effects Of Lime And Fertilizer On The Establishment Of White Clover In The Falkland Islands, J A. Kerr, Rosie Poultney

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.)-based pastures could improve low pasture and animal production in the Falkland Islands. However, establishment is difficult and expensive. Effects of lime and fertilisers containing nitrogen (N), phosphorus (P) and potassium (K) on white clover dry matter yield and root nodulation were experimentally assessed between 1986-88. Lime at 1 t/ha and 30 kg/ha P as triple superphosphate, separately improved clover yield. Nodulation was improved only by lime. Neither N nor K fertilisers affected on white clover establishment yields,

Complementarity Between Summer-Active Grasses And Cool-Season Annual Legumes In Temperate-Zone Pastures, W H. Johnston

IGC Proceedings (1977-2023)

The effect of mowing and subterranean clover (Trifolium subterraneaum) on plant density; basal area and total dry matter yield of the C perennial grasses Eragrostis curvula complex, cv. Consol and 4 Accession 4660, and Cenchrus ciliaris cv. American, and the c; Pllalaris aquatica cv. Sirocco was studied at Cowra, NSW, Australia between spring 1982 and spring 1987. C. cilaris did not persist. The density and basal area of phalaris was not affected by subterranean clover but declined with mowing, Clover reduced the density, basal area and summer dry matter ·yield of E. curvula while mowing was', advantageous. E. curvula …

Winter Grazing Rough Fescue Grasslands With And Without Preconditioning On Annual Pasture, W D. Willms, L M. Rode, B S. Freeze

IGC Proceedings (1977-2023)

Winter grazing of the fescue prairie is desirable to reduce the cost of feeding preserved forages and to conserving the native prairie. Rough fescue (Festuca campestris Rydb,), the dominant and most productive forage species in the foothills region, is highly sensitive to summer grazing but tolerates grazing while dormant. Since the forage quality declines after senescence, and the energy requirements increase in winter, this study was made to determine the feasibility of winter gmzing pregnant Hereford cows with and without preconditioning on annual pasture. The study, replicated over a 4-year period {n=4), used a 2x2 factorial design representing native …

Interaction Of Drill Type And Herbicide On Pasture Establishment In Semi-Arid Environments, W L. Lowther, R F. Horrell, P D. Johnstone, K D. Trainor

IGC Proceedings (1977-2023)

Results are presented from an overdrilling experiment comparing a conventional triple-disc drill with an' experimental single-pass strip­seeder drill designed to remove competiting vegetation mechanically; Herbicide application markedly increased herbage mass of sown species in the triple-disc treatments. ,However, herbage mass was. higher from the strip-seeder drill than the .triple-disc in both ihe' nbsence and presence of herbicide. The results indicate the potential of the strip-seeder drill technology for cost-effective establishment of pasture species in difficult environments.

Alfalfa Cultivar Selection From 30 Years Of Records In The State Of Illinois, Usa, Don W. Graffis

IGC Proceedings (1977-2023)

Data from alfalfa (Medicago sativa L.) cultivar trials in Illinois, USA from 1963 lo 1992 have been adapted to a computer software spreadsheet for storage and manipulation. The data recorded have been the percentage of check cultivar's yield. The average % of checks for a given cultivar is calculated after each year of recorded yield. The computer spreadsheet enables sorting of resultant yields. The sorting in descending order determines lhe top-performing cultivars. Criteria used lo determine cultivar suggestions for extension clienlele are: (a) a minimum of 3 harvest years in the region of cultivar suggestion, and (b) the cultivar …

Developing Eastern Gamagrass On A Conserved Forage, John A. Dickerson, Paul R. Salon

IGC Proceedings (1977-2023)

Bastern gamagrass (Tripsacum dactyloides L.) is highly regarded as a native forage resource in the prairie region of North America. Recent discovery of a gynomonoecious plant in Kansas has raised expectations that efficient seed production will be possible with the species. A possible use for eastern gamagrass is as a perennial haylage crop for dairy farms, replacing erosion-prone silage corn. Compared with corn silage, eastern gamagrass forage has higher crude protein, slightly lower energy, and higher neutral detergent fibre and acid detergent fibre. Breeding work is underway to develop hardy, high volume forage-producing strains with good seed production capability. …

Rangelands In Dry Mountain Areas, T Boyadgiev

IGC Proceedings (1977-2023)

The extent and characteristics of temperate and mountainous climatic zones, steeply dissected and mountainous areas, permanent meadows and pasture lands, and the trend of land use evolution and aspects of land degradation are presented and discussed. The rangelands improvement strategy in Bulgaria is based on mineral fertilisation of mountainous grasslands leading to an increase in production of dry material, protein, phosphorus and cereals, This reduces sheet erosion. Overgrazing and prolonged dry periods, causing a decrease in the number of species, are also discussed, Measures to improve grassland practices are proposed.

Improvement Strategies In Winter Cold Temperate Rangeland Ecosystems With Particular Reference To Extensive Grazing Lands Of Iran, A Koocheki

IGC Proceedings (1977-2023)

Traditional land use systems in Iran have been divided between crop production and livestock grazing. Grazing land management in most parts is based on pastoral nomadism which operates between plains as winter grazing lands and mountains as summer grazing lands. Mountainous areas are an important source of food and feed production for nomads and their herds. In Iran two main ranges of mountains, Elburz and Zagros, are the summer territory of nomadic pastoralists. At present 1.5% of total population of the country are nomads. They contribute as much as 27% of value added in the animal industry of the country. …

Winter Cold Temperate Rangelands: Improvement Strategies For Intensive Rangeland Ecosystems, B E. Allan, D Scott

IGC Proceedings (1977-2023)

Transfer of developed grassland technologies to rangelands is discussed in terms of environmental gradients and the options and constraints they impose. Winier feed limitation can be overcome through conserved feeds and various in situ systems involving special purpose pastures and feed banks. General animal nutrition can be improved through intensive development, low input systems, better control of range utilisation and, where appropriate, correction of mineral deficiencies. The emphasis in seeking quick and easy solutions to rangeland management problems is questioned, A more informed, environmentally sound and sustainable approach to rangeland fanning atlitudes and management is proposed. A stepwise process to …

The Effects Of Sunlight On The Decomposition Rate Of Opuntia Humifusa, Paul George, Elena Amonette, Celine W. Seder, Katherine Massaro

Science University Research Symposium (SURS)

Plant decomposition plays a critical role in community and ecosystem ecology by recycling minerals and returning nutrients to the soil. The rate of plant decomposition can be impacted by a multitude of factors including chemical composition of the plant, presence of decomposing microorganisms, temperature, and more. This study sought to quantify the effects of sunlight on plant decomposition. In this project, Opuntia humifusa (prickly pear) were placed outside on the Belmont greenroof to decompose in sunny and shaded environments. The plants were collected over a period of 12 weeks, and data on the masses of the decomposing plants was used …

Bodine: An Agent-Based Modeling Approach To Studying Localized Coexistence Across Environmental Heterogeneity, Alexandra Campbell

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Designing A Decision-Support Tool For Fertilizer Recommendations In Oil Palm Smallholders, Rana Farrasati

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Oil palm (Elaeis guineensis Jacq.), originally from West Africa, now accounts for 42% of global vegetable oil production and mainly includes key regions cultivated in tropical regions of Southeast Asia, West Africa, South America, and Central America. Despite its economic significance, the oil palm industry faces challenges of stagnant yields and large yield gaps, particularly among independent smallholders. These issues often stem from inadequate nutrient management practices and limited agronomic knowledge. Our objective was to quantify nutrient requirements for mature oil palm plantations as a basis to design a decision support tool (DST) for fertilizer recommendations. To do so, …

Understanding Limitations In Photosynthesis And Cold Tolerance In Panicoid Grasses: Maize And Sorghum, Fangyi Li

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

Sorghum and maize, both key crops within the Poaceae family (commonly known as the grass family), are staple foods in various regions and play a vital role in global food systems and economic development. These crops thrive in similar climates, particularly in warm, arid, and semi-arid regions. As subjects of extensive agricultural research, both maize and sorghum are being studied to enhance stress resistance and improve yield. Due to their botanical similarities, advances in one crop often inform practices in the other. The goal of this dissertation is to deepen our understanding of the photosynthesis process and cold tolerance in …

Water Lettuce And Its Control, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

Water lettuce (Pistia stratiotes) is a declared pest in Western Australia (WA). This factsheet describes the nature of the plant with links to requirements landowners/occupiers must adhere to and pest control methods.

Gorse And Its Control, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

Gorse (Ulex europaeus) is a declared pest in Western Australia (WA). This factsheet describes the nature of the plant with links to requirements that landowners/occupiers must adhere to, pest control methods and how to search, detect and report it.

Gorse is a Weed of National Significance (WoNS) present in Australian states and the Australian Capital Territory; it is not present in the Northern Territory. Gorse is a declared pest plant in WA.

Evaluation Of Dual Purpose Canola And Cereals Grazed With Cattle, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

The Department of Primary Industries and Regional Development conducted research to investigate and demonstrate the importance of dual-purpose crops (canola, wheat and barley) to improve the feed availability for cattle (in late autumn to early winter) in mixed farming systems of the high rainfall environment of Western Australia (WA).

The grain yield of a wide range of canola and cereal varieties sown in mid-April were unaffected by the grazing of cattle at a stocking rate of 20 to 22 dry sheep equivalent (DSE) per hectare (ha) for up to 4 weeks at Esperance in 2011.

The grazed crops yielded the …

Assessing The Above- And Belowground Productivity Of Fall-Planted Cover Crop Cultivars In Nebraska's Diverse Ecoregions, Bridget Mckinley

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Cover crops (CC) provide essential ecosystem services including soil conservation, nutrient cycling, and weed suppression, through the accumulation of aboveground (AGB) and belowground (BGB) biomass. While AGB has been widely studied, BGB contributions, particularly root development and distribution, remain less understood. This study evaluated fall-planted CC across three Nebraska ecoregions, assessing AGB productivity, BGB biomass, and correlations between ground cover, plant height, and AGB.

Thirty treatments, including grasses, legumes, brassicas, and mixtures, were evaluated over two fall growing seasons (2022–2023 and 2023–2024) at three UNL research centers in northeast, west central, and west Nebraska. AGB was highest at west site …

Bio-Based Sprayable Mulch For Weed Control In Row Crop Systems, Camila Chiaranda Rodrigues

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Improving current crop productivity levels requires transformative advancements in management, engineering, and science. One of the main challenges is the increasing difficulty of weed management due to herbicide-resistant weeds. There is a growing need for alternative weed management methods to reduce pesticide use and improve environmental safety. An emerging technology that is being developed is spray-on films which could help address these challenges. Spray-on films are liquid solutions that after spraying on the soil will dry and form a physical barrier. The overall objective of this research was to evaluate the effectiveness of a chicken feather bio-based sprayable mulch film …

The Role Of Siamese In G2 Checkpoint Regulation In Arabidopsis Thaliana, Martha A. Schwall

LSU Doctoral Dissertations

Cyclin-cyclin dependent kinase (Cyclin-CDK) pairs regulate progression through the checkpoints of the cell cycle. They bind with some specificity and must be bound to for their regulative properties to be active. The presence of cyclin-CDKs is conserved throughout eukaryotes, while differences in specifics exist between yeast, animals, and plants. In Arabidopsis, SIAMESE (SIM) is a CDK inhibitor that restricts progression through mitosis. Overexpression of SIM is required for endoreplication in Arabidopsis trichomes, and overexpression of SIM results in increased endoreplication in leaf epidermal cells. SIM is expressed at high levels in the root elongation zone, where it plays a …

Effect Of Crop Age On Seed Yield Of Arachis Pintoi At Two Sites In Costa Rica, Pedro J. Argel, Alfredo Valerio

IGC Proceedings (1977-2023)

Arachis pintoi is a forage legume well adapted to the humid tropics of Costa Rica. Seed production studies were carried out at two contrasting localities within the country, Gulipiles (very humid tropics) and San Isidro (seasonal evergreen tropical forest). The accessions CIAT 18748, 18744 and 17434 cv. Amarillo of A. pinloi were vegetatively planted at both sites. Seed yields were measured at 8, 12, 16 and 20 months post- planting inGulipiles, and at·8, 16 and 20 months in San Isidro. Mean seed yields among accessions were similar in San Isidro but significantly different in Gulipiles; however, the contrary occurred in …

Efficient Nitrogen Fertilization In Grass Seed Crops With Regard To Soil Mineral Nitrogen Content And Analyzing Grass Tillers In Spring, W Schoberlein, H J. Wahl

IGC Proceedings (1977-2023)

When applying the Nmln method in grass seed crops analogously lo that in cereal crops we proceed from the experience that for a mean level of mineralisation, the sum total of soil-borne Nm1n available to plants at the beginning of the growth period and Nd Input in the form of fertiliser will provide sufficient N to the crop. The total quantity of mineral soil-borne N and fertiliser N is considered as the nominal value. The required N input can be derived from the difference between nominal value and mineral soil-borne N (Nd = nominal value• Nrnin>· For Dactylis glomerata …

Effects Of Aneuploidy On Seed Production In Autopolyploid Forage Crops, A Elgersma

IGC Proceedings (1977-2023)

Between the selection of a population and its commercial use, several generations of multiplication are necessary. The essential feature in variety maintenance is that no genetic changes occur during multiplication. In seed-propagated species, however, during each multiplication cycle natural selection takes place at ihe gamete, zygote, seed and plant level. In induced autopolyploids high frequencies of aneuploids can occur. Aneuploidy not only affects the seed yield level, but also the selection processes that occur during multiplication. It may cause genetic shift and affect variety stability. Species differ in their tolerance to aneuploids. It is not possible to eliminate aneuploidy by …

Effects Of Ratooning And Protection From Diseases And Birds On Seed Production In Guinea Grass, Okoro Oji, F N. Madubuike, F.O C. Ezedinma

IGC Proceedings (1977-2023)

Effects of ratooning and protection from diseases and birds on seed production in guinea grass (Pannicum maximum L.) were assessed in a study from October 1986 to April 1987. Treatments included ratooning and mancozeb application with or without protection from birds (netting). Highest yield occurred with combined netting and mancozeb application. Mancozeb sp,aying without netting gave lower seed yield than netting without fungicide spraying. Seed yield, which generally decreased with ratooning, was lowest among unnetted and unsprayed crops. Prom anthesis to seed maturation lasted, on average, 9 days, and seeds borne on the upper part of the panicle matured …