Life Sciences Commons^™

The Influence Of Ph On The Forms Of Cadmium In Four West Australian Soils, S. S. Mann, G. S.P. Ritchie

Food Science and Nutrition

The forms of cadmium in soils affect its uptake by plants and hence its potential toxicity to animals and humans. We studied the effect of pH on the forms of native and added Cd in four West Australian soils which differed in their clay, hydrous oxide and organic matter content. The forms of Cd were extracted sequentially by KCl, BaCl₂, NaOCl, ammonium oxalate and concentrated acids.
The majority of Cd applied to a sandy soil was found in the soluble (KCl) and the exchangeable (BaCl₂) forms at all pH values. In the siliceous sand, the proportion …

Phosphorus Retention And Release From Sandy Soils Of The Peel-Harvey Catchment, G. S.P. Ritchie, D. M. Weaver

Food Science and Nutrition

In order to manage phosphorus (P) losses from soils to waterbodies, knowledge of the mechanisms through which P is retained or released from the soil is essential. Sandy soils of the Peel-Harvey catchment (Western Australia) were subjected to a range of environmental and management factors in the laboratory and field in order to gain an understanding of the mechanisms that affect the magnitude of P losses. Sandy soils accumulated P, despite having little sorption capacity, and this accumulation could be monitored by measuring an acid-extractable fraction. The potential, short-term P loss could be estimated by determination of water-soluble soil solution …

Al Toxicity Of Wheat Grown In Acidic Subsoils In Relation To Soil Solution Properties And Exchangeable Cations, S. J. Carr, G. S.P. Ritchie

Food Science and Nutrition

Toxic concentrations of soluble A1 in the subsoil decrease the yield of wheat grown on many yellow earths in the eastern wheatbelt of Western Australia. In our previous research (Carr et al. 1991), we observed variable plant response to high concentrations of soluble Al in subsoils of yellow earths in different regions of the wheatbelt. Environmental conditions (e.g. water supply) and/or an unidentified soil mitigating factor may have contributed to the variable plant response to soluble Al in some of the regions studied.
We collected ten soils from four regions of the eastern wheatbelt of Western Australia. In a glasshouse …

The Long-Term Fate Of Copper Fertilizer Applied To A Lateritic Sandy Soil In Western Australia, R. G. Mclaren, G. S.P. Ritchie

Food Science and Nutrition

A soil copper fractionation was carried out on soils sampled from plots in a long-term copper fertilizer trial on a lateritic sandy soil in Western Australia. At copper application rates up to 8.25 kg copper sulphate ha^-1, a high proportion of the applied copper was initially associated with the soil organic matter. During the course of the trial (20 years), a substantial proportion of this copper became redistributed to a residual soil fraction, i.e. the residue remaining after extractions to remove organic matter and iron oxides. However, significant redistribution of copper with time was not detected in plots …

H+/Oh- Excretion And Nutrient Uptake In Upper And Lower Parts Of Lupin (Lupinus Angustifolius L.) Root Systems, S. P. Loss, A. D. Robson, G. S.P. Ritchie

Food Science and Nutrition

The cultivation of narrow-leafed lupins (Lupinus angustifolius L.) increase rates of subsoil acidification, and this is thought to be partly related to their pattern of nutrient uptake and H⁺/OH^- excretion. The main hypothesis of this study was that H⁺ and OH^- excretion is not distributed evenly over the entire length of the root system but is limited to zones where excess cation or anion uptake occur. Seedlings of nodulated lupins were grown in solution culture using vertically split pots that allowed the upper and lower zones of the root system to be supplied with …

Life History And Description Of Immature Stages Of Aciurina Thoracica (Diptera: Tephritidae) On Baccharis Sarothroides In Southern California, David H. Headrick, Richard D. Goeden

Horticulture and Crop Science

Aciurina thoracica Curran forms galls on branches of at least three species of Baccharis in southern California. The egg, second and third instars, and puparium obtained from B. sarothroides Gray are described and illustrated. Aciurina thoracica's median oral lobe is described and illustrated. The egg is inserted singly into branch tips of B. sarothroides in early spring. Gall and larval growth continue through summer and fall, and pupariation occurs in early winter. Adults emerge in late winter or early spring, mate, and oviposit into newly forming branch tips. Adult behavior including courtship and copulation is described and compared with other …

The Expression Pattern Of The Tonoplast Intrinsic Protein Γ-Tip In Arabidopsis Thaliana Is Correlated With Cell Enlargement, Edward Himelblau, Herman Hofte, Dolors Ludevid, Maarten J. Chrispeels

Biological Sciences

The vacuolar membrane (tonoplast) contains an abundant intrinsic protein with six membrane-spanning domains that is encoded by a small gene family. Different isoforms of tonoplast intrinsic protein (TIP) are expressed in different tissues or as a result of specific signals. Using promoter-β-glucuronidase (GUS) fusions and in situ hybridization, we have examined the expression of γ-TIP in Arabidopsis thaliana. GUS staining of plants transformed with promoter-GUS fusions showed that γ-TIP gene expression is high in recently formed tissues of young roots. In the shoot, γ-TIP gene expression was highest in the vascular bundles of stems and petioles, as well as …

Elucidation Of The Complete Azorhizobium Nicotinate Catabolism Pathway, Christopher Kitts, Jerome P. Lapointe, Van Thai Lam, Robert A. Ludwig

Biological Sciences

A complete pathway for Azorhizobium caulinodans nicotinate catabolism has been determined from mutant phenotype analyses, isolation of metabolic intermediates, and structural studies. Nicotinate serves as a respiratory electron donor to O₂ via a membrane-bound hydroxylase and a specific c-type cytochrome oxidase. The resulting oxidized product, 6-hydroxynicotinate, is next reduced to 1,4,5,6-tetrahydro-6-oxonicotinate. Hydrolytic ring breakage follows, with release of pyridine N as ammonium. Decarboxylation then releases the nicotinate C-7 carboxyl group as CO₂, and the remaining C skeleton is then oxidized to yield glutarate. Transthioesterification with succinyl coenzyme A (succinyl-CoA) yields glutaryl-CoA, which is then oxidatively decarboxylated to …

The Occurrence And Effect Of A Protozoan Parasite, Ophryocystis Elektroscirrha (Neogregarinida: Ophryocystidae) On Overwintering Monarch Butterflies, Danaus Plexippus (Lepidoptera: Danaidae) From Two California Winter Sites, Kingston L. H. Leong, H. K. Kaya, Michael A. Yoshimura, Dennis F. Frey

Biological Sciences

1. Monarch butterflies, Danaus plexippus, from two overwintering populations, were found to have Ophryocystis elektroscirrha spores on their scales at rates between 53% and 68%. The frequency of butterflies with O.elektroscirrhaspores remained about the same between sites and throughout the winter.

2. The spores, recovered from all parts of the body of the butterfly, were most numerous on the abdomen, particularly near the posterior third.

3. Butterflies with spores survived as long as those without detectable spores at 10.1°C ±0.4 SE and 78.3% r.h. ±0.6SE. Insects with spores held at 19.4°C ±0.4SE and 44.9% r.h. ±1.5SE showed a …

Two-Dimensional Analysis Of Skim Milk Proteins Using Preparative Isoelectric Focusing Followed By Polyacrylamide Gel Electrophoresis, Hye-Hyun Y. Kim, Rafael Jiménez-Flores

Dairy Science

A preparative isoelectric focusing (IEF) method was applied to separate skim milk proteins using the Rotofor device in a pH 3-10 gradient containing 4 M urea/1% triton X-100. Each of the 20 fractions obtained from the Rotofor device was then analyzed by polyacrylamide gel electrophoresis (PAGE). Both urea-PAGE and SDS-PAGE were used to separate purified caseins and skim milk resulting in comparable two-dimensional pattern. The major bovine caseins (α_s1, α_s2, β, κ-casein) were resolved better on urea-PAGE. The α_s1- and β -casein were focused at pH ~ 4.5 and 4.8, respectively, whereas α_{s2 …}

Utilizing Iron In Turfgrass Management, David J. Wehner

Office of the Dean (CAFES) Scholarship

The purpose of this article is to review some of the basic information on iron, look at one of the discoveries made during the 1980s, and present some of the published research studies that have been conducted with iron on turfgrasses. Additional information on the use of iron can be found in popular magazines and in the proceedings of turfgrass conferences.

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Natural Resources Management and Environmental Sciences

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't …

Comparative Stress Dynamics Of Brood Stock Striped Bass Morone Saxatilis Associated With Two Capture Techniques, Reginal M. Harrell, Mark A. Moline

Biological Sciences

Mature striped bass (Morone saxatilis) were collected from the spawning reaches of the Choptank River, Maryland for the purpose of evaluating stress effects associated with capture. Two commonly used capture devices were evaluated—gillnetting and electrofishing. Results indicated that stress, as measured by changes in plasma corticosteroid and chloride concentrations, was significantly lower and recovery time quicker in those fish captured by electrofishing compared to gillnetting. By the end of the study period (48 h), those fish captured by electrofishing had recovered from the initial capture shock as evidenced by corticosteroid levels returning to near baseline levels. Conversely, at …

Pleistocene Terrestrial Vertebrates From Near Point San Luis, And Other Localities In San Luis Obispo County, California, George T. Jefferson, Harry L. Fierstine, John R. Wesling, Teh-Lung Ku

Biological Sciences

Terrestrial vertebrate remains were recovered from sediments that lie on remnants of the lowest marine wave-cut platform between Point Buchon and Point San Luis. Uranium series ages of these samples, which range from 83 to about 49 ka suggest a correlation to late Pleistocene climatic and eustatic events associated with marine oxygen isotope substage 5a, and establish a maximum age of ≈80 ka for the occurrence of terrestrial mammal fossils. The Point San Luis area assemblage appears typical of the late Pleistocene regional vertebrate paleofauna fauna from west-central California. Five mammalian taxa are added to the Pleistocene record from San …

Palmer Lter Program: Spatial Variability In Phytoplankton Distribution And Surface Photosynthetic Potential Within The Peninsula Grid, November 1991, Barbara B. Prezelin, Nicholas P. Boucher, Mark A. Moline, Elise Stephens, Keith Seydel, Kai Scheppe

Biological Sciences

No abstract provided.

Palmer Lter: Temporal Variability In Hplc Pigmentation And Inorganic Nutrient Distribution In Surface Waters Adjacent To Palmer Station, December 1991-February 1992, Barbara B. Prezelin, Mark A. Moline, Keith Seydel, Kai Scheppe

Biological Sciences

No abstract provided.

New Combinations In Gnaphalium (Asteraceae: Inuleae), G. Ledyard Stebbins, David J. Keil

Biological Sciences

Because of extensive morphological intermediacy, plants formerly distinguished at the species level as Gnaphalium beneolens, G. microcephalum, G. thermale, and G. wrightii are treated as intergrading races of the widespread G. canescens. The new combinations, G. canescens subsp. beneolens, G. canescens subsp. microcephalum and G. canescens subsp. thermale are made.

Enterprise Projects: Experiential Learning In Applied Entomology, Mark D. Shelton

Office of the Dean (CAFES) Scholarship

During 1924, when jobs for college students were difficult to find in San Luis Obispo, Calif., a group of entrepreneurial students at the California Polytechnic School negotiated an $80 bank loan from a local lender to raise chickens. Parents and college faculty cosigned the loan, and thus was born the Agricultural Enterprise Program.

Phosphorus Sorption By Gravels In Lateritic Soils, D. M. Weaver, G. S.P. Ritchie, R. J. Gilkes

Food Science and Nutrition

The effect of sesquioxidic gravels (>2 mm size fraction) on phosphorus sorption by two gravelly lateritic soils was investigated by phosphorus sorption experiments, X-ray diffraction, autoradiography and electron microscopy.In one soil the abundance and size of gravels decreased downslope. As the gravel content of both soils increased (13-61%), the proportion of large (>8 mm) gravels increased (0-70%). Phosphorus sorption increased in the order: (>2 mm fraction) < (whole soils) < (2 mm) decreased with increasing gravel size and increased with increasing time. Phosphorus sorption by whole soils decreased with increasing gravel content. Phosphorus sorption by the >2 mm fraction was principally by the external surfaces of the gravels. The estimation of phosphorus application rates for lateritic soils depended on the amount of phosphorus required by the plant …

Fitness: A Viable Adjunct To Treatment For Young Adults With Psychiatric Disabilities, Karen V. Unger, Gary S. Skrinar, Dori S. Hutchinson, Ann Yelmokas Mcdermott

Kinesiology and Public Health

The role of physical illness as a factor of mental illness and the positive effects of exercise on psychological functioning are examined A study of six persons who participated in a fitness program as an adjunct to an existing psychoeducational program is discussed. Methodology, description of the students, results, and personal responses to the fitness program are described. outcomes include a slight decrease in body fat and an increase in cardiovascular fitness as measured by oxygen intake. Although a formal measure of self esteem did not show changes over the course of the study, students report positive attitude changes. An …

Phenology Of The Western Cherry Fruit Fly (Diptera: Tephritidae) In Utah And Washington, Vincent P. Jones, Diane G. Alston, Jay F. Brunner, Donald W. Davis, Mark D. Shelton

Office of the Dean (CAFES) Scholarship

The flight period of the western cherry fruit fly, Rhagoletis indifferens Curran, was investigated in Utah tart cherry, Prunus cerasus L., orchards from 1983 to 1989 and in Washington sweet cherry, Prunus avium L., orchards between 1982 and 1988. In Utah, flies were first detected on 31 May 1989, but the average time of first detection was 9 June across nine site-years. In Washington, the first fly was detected on 23 May 1988, with an average first detection time of 1 June in the three site-years. On a degree-day (DD) scale (lower threshold of 5°C and no upper threshold), detection …

Soil Tests For Aluminum Toxicity In The Presence Of Organic Matter: Laboratory Development And Assessment, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Al toxicity in plants is related to the activity of Al³⁺ and Al-hydroxy monomers in the soil solution, whereas Al complexed with ligands such as fluoride (F), sulphate (SO₄^2-), and oxalate is not toxic. Estimation of toxic Al relies on measurement of “labile”; Al after short contact times with colorimetric reagents or cation-exchange resins. However, shifts in equilibrium may result in non-toxic forms of Al reacting with the complexing agent or resin.

A series of laboratory experiments tested the degree to which labile Al is related to Al³⁺ in simplified media and compared methods of …

Calcium Chloride Extractable Cadmium As An Estimate Of Cadmium Uptake By Subterranean Clover, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Cadmium (Cd) may accumulate in soils which have been regularly fertilized with phosphate fertilizers which contain Cd originating in rock phosphate. Soil was taken from three sites in the wheatbelt of Western Australia which were estimated to have received different amounts of phosphate fertilizer over the past decade. The pH was adjusted with dilute HCl or CaCO₃. No Cd was added experimentally. The concentration of Cd in the whole tops of Trifolium subterraneum cv Mt Barker grown in a glasshouse pot experiment increased from 0.2-0.8 µg g^-1 dry wt at pH 6.6-6.9 (1:5 0.01 M CaCl …

Review Of Pacific Marlins: Anatomy And Physiology, By Peter S. Davie, Harry L. Fierstine

Biological Sciences

No abstract provided.

A Comparison Of Soil Tests To Predict The Growth And Nodulation Of Subterranean Clover In Aluminium-Toxic Topsoils, M. G. Whitten, G. S.P. Ritchie

Food Science and Nutrition

Total Al concentration or pH in 1∶5 10 mM CaCl₂ extracts and exchangeable Al in 100 mM BaCl₂ extracts cannot always distinguish between Al-toxic and Al-nontoxic topsoils. Our objectives were to compare the abilities of different measures of Al and pH in various extracts to predict the effects of acidity on growth and nodulation of subterranean clover. In a glasshouse experiment, Trifolium subterraneum L. cv. Mt Barker was grown in acidic soils from 3 sites in the Western Australian wheatbelt with different histories of phosphate fertilizer application. The pH was adjusted to give a range of …

A Soil Test For Aluminium Toxicity In Acidic Subsoils Of Yellow Earths In Western Australia, S. J. Carr, G. S.P. Ritchie, W. M. Porter

Food Science and Nutrition

Many of the yellow earths in the Western Australian wheatbelt have naturally acidic subsoils which can reduce the yield of wheat grown on them. Current methods of assessing soil acidity cannot identify which soils have subsoil acidity severe enough to restrict wheat yields.

We conducted 53 field experiments at 34 sites in 5 regions over 3 years to determine the relationship between yield of wheat and several different indices for identifying subsoils with toxic concentrations of aluminium, Al. Initially, we identified that the concentration of aluminium, [Al], in the soil solution and in 1 : 5 0.005 M KCl extracts …

Life History And Descriptions Of Immature Stages Of Tephritis Baccharis (Coquillett) On Baccharis Salicifolia (Ruiz & Pavon) Persoon In Southern California (Diptera: Tephritidae), Richard D. Goeden, David H. Headrick

Horticulture and Crop Science

Tephritis baccharis (Coquillett) is bivoltine and monophagous on Baccharis salicifolia(Ruiz & Pavon) Persoon in southern California. The egg, the second and third instar larvae, and puparium are described and illustrated. Eggs are inserted singly into terminal buds of main and axillary branches in late winter or early spring. First instar larvae hatch and tunnel into the pith just basad to the apical bud where they initiate gall formation. Gall and larval growth continue slowly into the fall, when pupation occurs. Most F₁ flies emerge, mate, and after about one week begin oviposition. Some F₁ flies that emerge …

Spatial And Temporal Continuity Of Kangaroo Rat Populations Shown By Sequencing Mitochondrial Dna From Museum Specimens, W. Kelley Thomas, Svante Pääbo, Francis X. Villablanca, Allan C. Wilson

Biological Sciences

The advent of direct sequencing via the polymerase chain reaction (PCR) has opened up the possibility of molecular studies on museum specimens. Here we analyze genetic variation in populations over time by applying PCR to DNA extracted from museum specimens sampled from populations of one species over the last 78 years. Included in this study were 43 museum specimens of the Panamint kangaroo ratDipodomys panamintinus from localities representing each of three geographically distinct subspecies. These specimens were originally collected and prepared as dried skins in 1911, 1917, or 1937. For each specimen, a 225-bp segment of the mitochondrial genome …

Life History Of Paracantha Gentilis (Diptera: Tephritidae), David H. Headrick, Richard D. Goeden

Horticulture and Crop Science

The life history of Paracantha gentilis Hering in southern California is described. This stenophagous tephritid reproduces in the capitula of native Cirsium thistles. Courtship and mating behavior are described from field and laboratory observations. Territorial and courtship behavior of males and the morphological characters involved in possible male pheromone emission are described and illustrated, as are the oviposition behavior and reproductive morphology of females. Egg clutch sizes ranged from one to 13 eggs, with a maximum of six clutches per capitulum. Larvae fed gregariously within stage-specific niches. Pupariation occurred in the capitula, from which adults emerged in mid-June through early …

Cost-Effective Wilderness Fire Management: A Case Study In Southern California, Christian A. Childers, Douglas D. Piirto

Natural Resources Management and Environmental Sciences

Federal wilderness fire management policies have been scrutinized since the catastrophic fires in the Greater Yellowstone Area in 1988. While wilderness tire management objectives are still aimed at recreating natural fire regimes, all USDA Forest Service fire management programs must be cost-effective. Since current Forest Service economic analyses do not fully represent the value of fire to wilderness, a cost-effectiveness analysis was developed to compare wilderness fire management options. The analytical procedure is briefly reviewed, illustrated through a southern California case study and case study results are discussed. These results suggest that containment of some tires may be more cost-effective …