Plant Biology Commons^™

Implications Of Grazing Experiments Which Employ Only One Grazing Level Per Treatment, David I. Bransby

IGC Proceedings (1977-2023)

Stocking rate is one of the most powerful driving variables in grazing ecosystems, but its influence on animal production is mediated through effects on pasture sward state, and associated effects on quantity and quality of forage consumed by animals. Consequently, confounding important sward state char­acteristics with treatments in grazing experiments will often mask treatment effects and lead to erroneous conclusions. While this problem has generally been recognized (e.g. Mott and Lucas, 1952; Wheeler et al. 1973 ; Hodgson, 1985), attempts to overcome it appear to be less than satisfactory. The aim of this paper is to discuss methods of stocking …

Experiments And Extension Of The Utilization And Improvement Of Sandy Rangelands In Nei Monggol (Inner Mongolia) Autonomous Region, China, Hou Yong-Zhang, Bai Ri-Sheng, Li Xhang-Chun

IGC Proceedings (1977-2023)

There are about 60 million ha. of rangelands available for livestock in Nei Monggol (Inner Mongolia) Autonomous Region. In the great vast area of rangelands there are 4 rather large sandy rangelands: 1) the Hulun Beir Sandy Rangeland; 2) the Kerching Sandy Rangeland ; 3) the Hunshandak Sandy Rangeland ; and 4) the Maowoos Sandy Rangeland. Their total area covers about 20.8 million ha and accounts for more than 1/3 of that available in N. M. A. R.

The Hulun Beir Sandy Rangeland located in the northeast part of N. M.A. R. - N 47° 40'-50°12' E 118°3!'-121°03' 355 km …

Production De Viande Bovine Et Ovine Sur Prairie Dans Les Monts Sudetes, Janina Fatyga

IGC Proceedings (1977-2023)

Par suite du depeuplement des villages et de !'abandon de la culture dans des zones situees en altitude dans !es Sudetes, on y observe l'accroissement de la superficie des paturages perma­nents. Des 1968, on y cree des zones de pature OU en ete de jeu­nes bovins et des ovins provenant des fermes situees plus bas sont conduits en permanence. L'importance du phenomene est illustre par le fait qu'a present, sur le terrain d'une seule region de Walbrzych, il y a 103 bases de pature d'une superficie de 7.000 ha, appartenant a 54 fermes d'etat ou paissent environ 25.000 ovins et …

A Standard Livestock Unit (Slu) For Defining Stocking Rate In Grazing Studies, D J. Minson, P C. Whiteman

IGC Proceedings (1977-2023)

The weight of animals and hence their intakes vary between grazing experiments and at different stages of the same study but the results are often presented as though these differences do not affect grazing pressure (Roberts, 1980). Thus we have sheep/ha and cattle/ha, with no indication of the effects that differences in intake and hence grazing pressure might have on the pasture/animal interaction. Pastures are utilized by different classes of stock and there is a need to have a common basis for comparing their productivity. These problems would be over­come by the use of a Standard Livestock Unit (SLU).

The Ecophysiology Of The Enigmatic Namib Succulent, Lithops Ruschiorum, Garrett Macleod Althausen

Environmental Studies Senior Theses

Water availability is the primary constraint for plant survival and reproduction in hyper-arid ecosystems. In such environments, plant fitness depends on an alignment between physiological traits and limited water resources. The Namib Desert of Namibia exemplifies this extreme selection pressure. Within the Namib Desert, Lithops ruschiorum, a succulent endemic to the gravel plains, exhibits habitat specificity and numerous physiological adaptations to cope with the hyper-aridity.

This research explores the intersection of two fitness strategies for L. ruschiorum: habitat selection and exploitation of alternative moisture sources. The first chapter explores the population dynamics and micro-site habitat conditions preferred by …

Isolation And Enumeration Of Salmonella Enterica From Fresh Lettuce (Lactuca Sativa L.) Leaves And Its Susceptibility To Different Washing Protocols, Meinard Talplacido, Angella Melissa Carlos, Bryan Rey Oliveros, Ida Dalmacio

The Philippine Agricultural Scientist

Lettuce is one of the most consumed fresh produce items in the country, but it also serves as a vehicle for human pathogens, posing a risk of foodborne illness. This study used conventional microbiological and molecular analyses to obtain the concentration and prevalence of Salmonella enterica in fresh Green Ice and Iceberg lettuce leaves from selected supermarkets in Los Baños, Laguna, Philippines. The efficacy of different household washing procedures in reducing S. enterica on lettuce leaves was also investigated. Of the 19 composite Green Ice lettuce and 21 composite Iceberg lettuce samples tested, 5.26% and 4.76%, respectively, were contaminated with …

Effects Of Water Deficit Stress And Mycorrhiza, Azotobacter Chroococcum, And Azospirillum Lipoferum Biofertilizers On Yield And Morphological Traits Of Wheat (Triticum Aestivum L.) Cultivars, Mehdi Rashnou, Farshid Aref, Bahram Amiri, Masoud Rafiee, Mahdi Zare

The Philippine Agricultural Scientist

Crop production in various parts of Iran faces significant constraints due to insufficient water availability, which is a major challenge to agricultural productivity. To study the effects of water deficit stress on shoot and root growth characteristics and seed yield of different wheat (Triticum aestivum L.) cultivars, an experiment was conducted using a randomized complete block design with a split-plot arrangement and 3 replications. The main factor was irrigation treatments (full irrigation during the growing season [S1], water withholding after flowering [S2], and water withholding after grain filling at the milk stage [S3]). The secondary factors were wheat cultivars …

Arkansas Corn And Grain Sorghum Research Studies 2024, Jason Kelley, Travis Faske

Arkansas Agricultural Experiment Station Research Series

The 2024 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, nematode, and insect management; economics; irrigation; agronomics; soil fertility; drone use; and research verification program results.

Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

The reports inform and guide our long-term recommendations, but should not …

Summaries Of Arkansas Cotton Research 2024, Fred M. Bourland

Arkansas Agricultural Experiment Station Research Series

Planted cotton acreage in Arkansas increased in 2024 to 670,000 planted acres, which was 160,000 acres more than in 2023 when Arkansas producers planted approximately 510,000 acres of cotton. A wet spring, and two hurricanes in three weeks in late summer/early fall led to a slight decrease in harvested acres that culminated in a final number of 640,000 (https://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=ARKANSAS). Producers harvested 640,00 acres of cotton, which ranked third nationally, behind Texas and Georgia (https://downloads.usda.library.cornell.edu/usda-esmis/files/k3569432s/nk324887m/qn59s0097/cropan25.pdf). The total harvested acreage is the greatest amount since 680,000 acres in 2011. The average cotton yield in Arkansas in 2024 was …

Quantifying Dna Methylation In Response To Drought Stress In Silver Firs (Abies Alba), Julia K. Brandfonbrener

Biology Honors Projects

As future droughts are expected to increase in duration and severity due to climate change, forest managers may need to evaluate which coniferous species are the most resilient in drought events. Drought stress induces changes in physiology, including decreases in water potential, stomatal closure, pigment degradation, and leaf senescence (Jongdee et al., 2002, Munné-Bosch & Alegre, 2004, Heitholt et al., 1991). These physiological changes are associated with epigenetic regulation of gene expression in response to abiotic stressors (Alongi et al. 2025) and have been highly studied in crop plants and Arabidopsis. This project examines the photosynthetic and epigenetic response …

Changes In Elephantgrass Plant Components With Maturity: 1. Percentage Dry Yield, P Mislevy, F G. Martin, M B. Adjei

IGC Proceedings (1977-2023)

Elephantgrass (Pennisetum purpureum Schum.) biomass can be a source of energy for tropical regions of the world because of its high dry matter production (Mislevy et al., 1986 ; Prine et al., 1987). Research has shown the production of energy (meth­ane) from biomass can be best understood through systems analysis methodology that integrates the availability of land, climate, production inputs, plant quality, etc. To assess avail­able technology and identify information gaps Biomass to Methane (Biomet) models have been developed to determine the impacts of basic growth processes in response to the crops environment (Mishoe et al., 1987). Biomass growth …

Teneurs En Constituants Parietaux Et En Matieres Azotees Des Ligneuz Fourragers D'Afrique Occidentale, A R. Kone, D Richard, H Guerin

IGC Proceedings (1977-2023)

Dans !es pays intertropicaux d'Afrique, l'elevage est surtout extensif et l'alimentation du betail est essentiellement basee sur le paturage nature! ou la strate ligneuse (arbres, arbustes) fournit des fourrages verts pendant la periode seche de l'annee, periode pendant laquelle le tapis herbace est sous forme de paille sur pied. Les ligneux sont done tres importants dans l'alimentation des ruminants domestiques et ii est necessaire d'en connaitre la composition chimique comme dans le cas des fourrages herbaces.

Evaluation Of Tree Legumes Species At Different Agroclimatic Zones Of Indonesia, Mas'ud Panjaitan, R Jessop, W W. Stur

IGC Proceedings (1977-2023)

The population of Indonesia is over 145 million and more than 56 % of them earn their living from agriculture (Bi. Stat. Ind., 1983). A major problem in the development of improved animal production has been the shortage of feed and the generally low nutritive value of tropical forages which limit livestock pro­duction in Indonesia (Asian Agriculture Survey, 1969). The production of feed of adequate quality for ruminants is an important consideration particularly for small holders. In many situations, nitrogen fixing legume trees can be used as a high protein feed supplement which improves the utilization of grasses and crop …

Valeur Nutritive D'Un Parcours Mixte A Acacia Cyanophylla, Atriplex Nummularia Et Medicago Arborea, Y Saadani, C Kayouli

IGC Proceedings (1977-2023)

II existe tres peu de donnees concernant la valeur nutritive des arbustes fourragers ; les rares etudes realisees en Tunisie ont porte surtout sur leur productivite, la charge animale et sur leur appetence (Hamrouni et Sarson, 1975; Ben Boubaker, 1985). L'objectif de ce travail est d'etudier la valeur nutritive des feuilles et brindilles d' Acacia cyanophylla, d' A triplex nummula­ria et de Medicago arborea ainsi que leur contribution dans la ration de caprins et d'ovins.

Utilization Of Native Mediterranean Fodder Trees By Dairy Goats, M Meuret

IGC Proceedings (1977-2023)

Few data are available on utilization of fodder trees and shrubs by lactating goats. In most cases, predictions of animal performances on the basis of recommendations obtained from standard reference trials, do not correspond with production results achieved on the farm. Using measurements in digesti­bility cages and on rangelands (chromic oxide marker), we recorded intake, apparent digestibility of diets and perform­ances of goats well used to rangelands and browsing fresh oak foliage (Quercus ilex and Quercus pubescens).

Phenols As Defensive Compounds In Birch (Betula Spp.) Metabolism Of Platyphylloside In Goats, Rabbits And Hares, R T. Palo, G Iason, P G. Knutsonn

IGC Proceedings (1977-2023)

Herbivores of the boreal forest like moose (Alces alces), hares (Lepus spp.) and birds (Tetranoidae) use birch as a major feed source. The tree is of medium preference to the animals and is low in available nutrients for most of the year. Apart from a high amount of lignified cell walls it also contains con­siderable amounts oflow molecular phenolic substances (Palo, 1984). A herbivore feeding on birch could thus be excepted to ingest large amounts of phenols. These are in general enough fat soluble to enter animal cells expected to ingest large amounts of …

Forage Production And Nutritive Value Of Leucanea Leucoephala In Southern Puerto Rico, L E. Tergas, R Milton Martinez, A V. Mendez Cruz

IGC Proceedings (1977-2023)

Leucaena leucocephala (L.) is a perennial schrub native to Mexico, Central America and the Caribbean, considered by investigators as a valuable forage legume because of its capacity for high production of digestible forage with a high protein content and tolerance to drought in semiarid regions with annual rainfall less than 1,000 mm (Skerman, 1977). The soil fertility of the semiarid region in southern Puerto Rico is adequate, but rainfall distribution is limiting for forage production and nutritive value. There is a demand for a suit­able and inexpensive source of high quality forage to improve the diet of the grazing cattle …

Effect Of Chemical Composition Of Roughages On Their Degradation Characteristics In The Rumen And Their Relationship With The < In Vitro > Organic Matter Digestibility, S Lopez, Dolores Carro, J S. Gonzales, Conchita Carpintero

IGC Proceedings (1977-2023)

The microbial fermentation of feeds in the reticulo-rumen allows ruminants the utilization of feeds with amounts of cell wall components, i.e. roughages. This rumen fermentation can be affected by the feed chemical composition and numerous techniques have been developed for its determination (Van Soest, 1982). The objective of the present work is to investigate the effect of the chemical composition of forages preserved under differ­ent methods on their degradation characteristics in the rumen determined by the « in sacco » method and to study the rela­tionships between the « in vitro» organic matter digestibility (IVOMD) and the rumen degradability.

Rumen Degradation Of Various Grass Species At Different Stages Of Growth, L J. Halliday

IGC Proceedings (1977-2023)

The species and cultivars sown depends on the farming sys­tem practiced. These developing swards are however, always invaded by native species including Agrostis, Paa and Festuca spp. which are generally referred to as 'weed' grasses. While the merits of Lolium spp. are well documented (Minson et al. 1960; Norton, 1982) information on the weed grasses is limited (Hag­gar, 1976). The potential for milk and meat production is dependent on the supply of utilizable nutrients to the animal's tissues which in turn is largely governed by the ability of rumen microbes to degrade plant cell walls. Although the degradability of dry …

Apparent Digestibility, Dynamics Of Rumen Fermentation And Sites Of Digestion Of Hays Of Leucaena Leucocephala (Lam) De Wit Cv. Peru, N M. Rodreiguez, I Borges

IGC Proceedings (1977-2023)

Protein deficiency, among others, is a common problem for livestock production in tropical regions. The use oflegumes has been suggested as a solution and Leucaena leucocephala has shown a great potential due to its capacity of nitrogen (N) fix­ation and dry matter (DM) production (NAS, 1984). However, very little is known about its nutritive value regarding its protein-energy balance and the process of digestion. The present work aimed the evaluation of the nutritive value of hays of Leucaena leucocephala cut at two stages of growth, through trials of apparent digestibility, dynamics of rumen fer­mentation and partition of digestion.