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Studies On The Giant Mealie Witchweed, Striga Forbesii Benth., In Zimbabwe, David Allen Knepper Oct 1989

Studies On The Giant Mealie Witchweed, Striga Forbesii Benth., In Zimbabwe, David Allen Knepper

Biological Sciences Theses & Dissertations

Of the seven species of Striga found in Zimbabwe, S. forbesii Benth. is currently the most destructive in terms of crop damage. Owing to its limited occurrence worldwide as a pest of crops, relatively little work has been done on this species.

Striga forbesii has been found to be a consistent problem on both maize and sorghum in the Hunter's Road District of KweKwe, Zimbabwe. Results of a pot study and field observations, indicate S. forbesii can successfully parasitize Urochloa panicoides Beauv., Sorghum arundinaceum (Desv.) Stapf, and Rottboellia cochinchinensis (L.) L.f., all of which are widespread weeds of arable land. …


Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti Sep 1989

Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti

Bulletins 4000 -

Subterranean clover (Trifolium subterraneum L.) is the most important annual pasture legume in Western Australia, forming the basis of some 6.5 million ha of annual pastures. The success of subterranean clover may be attributed to its ability to increase soil fertility as a consequence of nitrogen fixed, to withstand heavy grazing, to control soil erosion and, with some cultivars, to tolerate waterlogging. Fungal diseases have been a major limitation to the productivity of subterranean clover, affecting both the amount of plant matter and the quantity of seed produced.

Annual medic (Medicago spp., in particular M. polymorpha L.) is also an …


A Comparison Of Chemical Composition & Fermentation Patterns Of Alternative Silages To Whole Plant Corn Silage, Susan Fox Jul 1989

A Comparison Of Chemical Composition & Fermentation Patterns Of Alternative Silages To Whole Plant Corn Silage, Susan Fox

Masters Theses & Specialist Projects

A comparison of the relationship of fermentation to chemical composition was made for forages which were wilted and ensiled at 35 to 45 percent dry matter. Trial I consisted of three forages ensiled in October, 1981: interseeded soybeans and grain sorghum. whole plant corn with added anhydrous ammonia, and whole plant corn with shelled corn added at a rate of 150 kg/t of fresh forage. Trial II consisted of two forages ensiled in 1982: interseeded soybeans and pearlmillet, and wheat. Temperatures of fermentation were collected, and chemical composition during the first 25 days of fermentation analyzed.

Production data were also …


Isolation & Characterization Of A Type I Topoisomerase From The Hypocotyls Of Etiolated Soybeans, Rick Dye May 1989

Isolation & Characterization Of A Type I Topoisomerase From The Hypocotyls Of Etiolated Soybeans, Rick Dye

Masters Theses & Specialist Projects

Topoisomerases are enzymes of critical biological significance. Despite this fact, little data specific to the topoisomerases of higher plants has been published. This research was undertaken to isolate and characterize a higher plant topoisomerase from soybean hypocotyls to further the understanding of the structure and function of these enzymes.

Nuclei were isolated from frozen hypocotyls of 4 day old etiolated soybeans by homogenization and centrifugation, then lysed by gentle stirring in the presence of 1.5 mM ammonium sulfate. The resultant extract was desalted and purified by column chromatography on DEAF sepharose, 5-200 sephacryl and CM cellulose. The components of the …


The Effects Of Spacings & Cultivars On Biological Yields, Yields, Component Of Yield & Harvest Index Of Green Bush Snap Bean (Phaseolus Vulgaris L.), Widodo May 1989

The Effects Of Spacings & Cultivars On Biological Yields, Yields, Component Of Yield & Harvest Index Of Green Bush Snap Bean (Phaseolus Vulgaris L.), Widodo

Masters Theses & Specialist Projects

The effects of cultivars and plant spacings on biological yield, seed yield, seeds per pod, average seed weight, and harvest index of beans (Phaseolus vulgaris L.) were studied in 1987 and 1988. Two cultivars, 'Blue Lake 27' and 'Kentucky Wonder 125' and four plant spacings -- 7, 14, 21, and 28 cm, constituted eight treatments that were arranged in a split-plot with four replications. Each experimental unit or hill consisted of five plants -- four in the corners and one in the center of a square. Spacings treatment were established by varying the distance between the center plant …


Bulletin No 4146 - Commercial Production Of Pawpaws In Western Australia, J. R. Burt, B. L. Toohill May 1989

Bulletin No 4146 - Commercial Production Of Pawpaws In Western Australia, J. R. Burt, B. L. Toohill

Bulletins 4000 -

The papaw (Carica papaya L.) is a native plant of Central America. It produces its highest yields of good quality fruit in tropical regions.

The tree is short-lived and rarely produces crops for more than two or three years. It is quick growing and soon reaches a maximum height of 5 to 7 m. It is usually unbranched, but may branch after either injury to the top or cutting back.


The Biology Of Skeleton Weed In Western Australia, J Dodd Jan 1989

The Biology Of Skeleton Weed In Western Australia, J Dodd

Experimental Summaries - Plant Research

Effects of height of cutting on the rate of stem regrowth, 89ME116. Response of Gorteria to grazing, 88PE28. Biology of P. globifera in stubble paddocks, 89ME75, 89ME76. Comparative phenology of P. globifera suffruticosa, 89ME77. Establishment and spread of the leaf mining moth, Dialectica scalariella. 89PE8. Intensive monitoring of the leaf mining moth and Patersons curse at Muresk, 89NO65 - 89NO670.


Flower : Predicting Flowering Times Of Cereal Crops, G A B Elliott, Stephen Loss Jan 1989

Flower : Predicting Flowering Times Of Cereal Crops, G A B Elliott, Stephen Loss

Journal of the Department of Agriculture, Western Australia, Series 4

FLOWER is a computer program which predicts the flowering date of a given wheat or barley variety at a specified location and sowing date. Department of Agriculture agronomists, breeders and advisers are using the program to provide useful information on how the development of cereals responds to different environments across Western Australia's cereal growing areas.


Increased Returns From Agronomic Inputs In Early Sown Cereal Crops, W K. Anderson Jan 1989

Increased Returns From Agronomic Inputs In Early Sown Cereal Crops, W K. Anderson

Journal of the Department of Agriculture, Western Australia, Series 4

When crop variety and soeing dae are matched so that flowering occurs in the 'window' for a particular site, grain yields are increased and yield response to inputs such as nitrogen fertilizer and seeding rate is magnified.

This response occurs because the srop's potential for setting and filling grains is much improved by sowing at the optimum time. However varieties differ in their yield potential because they have different lenghts of growing season, which probably affects grain numbers, and because they have different inherent grain sizes. These differences affect the way varieties react to sowing date. Figure 1 shows how …


Early Sowing Of Ceral Crops In Low Rainfall Areas, R J. Delane, John Hamblin Jan 1989

Early Sowing Of Ceral Crops In Low Rainfall Areas, R J. Delane, John Hamblin

Journal of the Department of Agriculture, Western Australia, Series 4

One of the objectives of the Department of Agriculture's crop research in the low rainfall, northern wheatbelt is to develop crop varieties and management practices that will make best use of stored water on both sandplain and fine textured soils. Sowing a crop early will improve its water use efficiency and yiel in low rainfall areas.


Frost Injury To Wheat, S P. Loss Jan 1989

Frost Injury To Wheat, S P. Loss

Journal of the Department of Agriculture, Western Australia, Series 4

Frost injury has not been a major concern to the Western Australian wheat industry despite causing spectacular but irregular crop losses on some farms.

The development of suitable herbicides, direct drilling technology and the adoption of early flowering varieties in the late 1970s and early 1980s led to wheat crops being sown and flowering earlier than previously. This resulted in an increase in the incidence of frost damage.

Research into frost indicates that most wheat producers face low to moderate risks of yield loss caused by frost. However, individual farms in particular years can suffer devestating widespread losses. Grost injury …


Reproduction Of Lindera Melissafolia In Arkansas, Robert D. Wright Jan 1989

Reproduction Of Lindera Melissafolia In Arkansas, Robert D. Wright

Journal of the Arkansas Academy of Science

Field reproduction was investigated in several populations of the endangered dioecious species Lindera melissifolia. Fruit set was light and erratic, and even where fruiting was heavy no effective seed bank was found. Field transplantation of greenhouse-grown seedlings was successful for one growing season. Rhizome sprouting was widespread, and produced rapid recovery from fire. Without enhancement of natural reproduction, the species will probably decline.


The Effect On Farm Profit Of Conserving Stubble To Prevent Wind Erosion, A D. Bathgate Jan 1989

The Effect On Farm Profit Of Conserving Stubble To Prevent Wind Erosion, A D. Bathgate

Journal of the Department of Agriculture, Western Australia, Series 4

Over-grazing of stubbles is a major cause of winf erosion on WesternAustralian farms. Stubble contributes to the 'roughness' of the paddock; as the roughness is reduced, the risk of winf erosion is increased.

The risk of lupinosis in sheep has previously reduced the likelihood of lupin stubble being over grazed, but the development of Gungurru, a phomopsis-resistent variety of lupin, has increased the potential for over-grazing and hence the probability of wind erosion.

This article describes the economic benefit (or cost) of conserving stubble at the conservation standards.


Early Sowing : One Key To Improved Yields Of Cereal Crops, M W. Perry, Wal Anderson, Rob Delane Jan 1989

Early Sowing : One Key To Improved Yields Of Cereal Crops, M W. Perry, Wal Anderson, Rob Delane

Journal of the Department of Agriculture, Western Australia, Series 4

Early sowing of cereal crops is one of the most important management practices through which Western Australian cereal growers can increase yields.

Researchers have long known that in theory early sowing should mean improved growth and water use efficiency - which both contribuite to increased yields. Application of this knowledge has had to await new tillage and herbicide technology, but recent research in the northan and central wheatbelt has now demonstrated the advantages of early sowing in practice. And more exciting yet, there is evidence that yield responses to weed control and applied fertilizers may also be greater in early …


Allelopathic Observations In Rice (Oryza Sativa L.) To Ducksalad (Heteranthera Limosa), R. H. Dilday, Paolo Nastasi, Roy J. Smith Jr. Jan 1989

Allelopathic Observations In Rice (Oryza Sativa L.) To Ducksalad (Heteranthera Limosa), R. H. Dilday, Paolo Nastasi, Roy J. Smith Jr.

Journal of the Arkansas Academy of Science

More than 50 weed species infest drill-seeded rice in the U.S. and one of the most prevalent aquatic weeks is ducksalad (Heteranthera limosa). During the summer of 1988, a field experiment was conducted to identify rice accessions from the USDA/ARS rice germplasm collection for allelopathic effects to ducksalad. In this field experiment, 5,000 accessions were evaluated for allelopathic activity. Five to seven seeds of each rice accession were planted in hills about 75cm apart in two replications. Allelopathic activity was recorded as 1) radius of the area affected by allelochemical from the base of the rice plant and 2) percentage …


Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt Jan 1989

Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt

Experimental Summaries - Plant Research

a. Trial 88GE34

Cultivar evaluation in machine sown plots.
Location: NMRS

The higher seed yield of Serena compared to the other cultivars resulted in better early forage .production as well a legume dominated pasture.

b. Trial 88TS 63 and 88TS 65

Wheat yields following pastures.
Location: 88TS63 - Perenjori and 88TS65 - Three Springs.

There was no response to nitrogen in either biological yield or grain yield of wheat sown over volunteer based pasture at the Three Springs site. All pasture treatments resulted in similar wheat yields except for Sava because of poor control of the snail medic under the …


Farming Systems Research/Extension And The Concepts Of Sustainability, Charles A. Francis, Peter E. Hildebrand Jan 1989

Farming Systems Research/Extension And The Concepts Of Sustainability, Charles A. Francis, Peter E. Hildebrand

Department of Agronomy and Horticulture: Faculty Publications

Farming Systems Research and Extension (FSR/E) has strongly influenced the direction of agricultural development over the past two decades. Involving farmers, change agents and researchers, this participatory approach to technological improvement has evolved as an efficient means to develop individual components and more integrated systems that are uniquely suited to specific biophysical and socioeconomic conditions. Farmers with similar conditions and for whom specific recommendations are appropriate are grouped, in FSR/E, into identifiable Recommendation Domains. The technologies recommended conform with the biophysical and socioeconomic constraints that create environments within the domains, based on the philosophy that new technologies must conform with …


Concetta Tm (Papconc) C.V. (Rose Plant), Ellen T. Paparozzi Jan 1989

Concetta Tm (Papconc) C.V. (Rose Plant), Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

A new and distinct variety of rose plant of the hybrid tea rose class, which was originated as a sport of the rose Gabriella; characterized by its bright orange red, well-formed hybrid tea type blooms with dark velvet overtones on the outer edges of the open flower; disease resistant with everblooming habit and outstanding pot forcing characteristics.


Introducing Onslow, Western Australian Department Of Agriculture Jan 1989

Introducing Onslow, Western Australian Department Of Agriculture

Grain and other field crops published reports

Onslow Barley........ a new breed of barley for the southern high rainfall areas (see map VH,H4 &H5). Suited to May plantings, Onslow is the first barley developed specifically for the long growing seasons in these areas.

For the first time barley growers have a variety designed for those 4 t/ha plus yields which research shows are possible with early sowing.

Onslow is the first of a new breed of barley cultivars developed in Western Australia specifically for the southern high rainfall areas which have a long growing season.


The Short Term Effects Of Manganese Toxicity On Isocitrate Dehydrogenase In Wheat & Tobacco, Juergen Pfeiffer Dec 1988

The Short Term Effects Of Manganese Toxicity On Isocitrate Dehydrogenase In Wheat & Tobacco, Juergen Pfeiffer

Masters Theses & Specialist Projects

The short term effects of high manganese levels (80 mg/L) on wheat and tobacco isocitrate dehydrogenase (IDH) activity were compared. The change in activity was then compared to the concentrations of manganese in the tissues.

As the time of manganese exposure increased, the fresh weight IDH activities in wheat and tobacco decreased. In contrast both control groups had similar enzyme activities every 6 hr over the 24 hr test period. The decrease in IDH activity of wheat and tobacco plants in experimental groups seemed to be related to an increase of the manganese in the leaf tissue. The slower decrease …


Miscellaneous Production 23/87 - Animal Production In The Spinifex And Shrubland Regions Of Western Australia, D. Burnside Jul 1988

Miscellaneous Production 23/87 - Animal Production In The Spinifex And Shrubland Regions Of Western Australia, D. Burnside

Animal production and livestock published reports

The role of the Rangeland Management Branch is to promote the sustained economic use of the rangeland resource. It provides research and extension services to the pastoral industry, provides advice on the condition of the range resource to Government and provides technical information on rangelands to other rangeland managers. A principal objective to be met in fulfilling that role is the development and promotion of economically efficient place systems that conserve the rangeland resource. At the inaugural Pastoral Soil Conservation Districts Conference in Meekatharra in May 1987, pastoralist delegates emphasized the importance of achieving that objective within the various soil …


Soil Science Research Report - 1988 Jan 1988

Soil Science Research Report - 1988

Soil Science Research Reports

Tillage Experiments

An Economic and resource analysis of deep tillage to reduce soil compaction for crop production .......... 1

Effect of phosphorus rate, method of application and tillage on soybean yield in Nebraska .......... 7

Increasing nitrogen use efficiency by dryland sorghum under conventional disk and no-tillage systems .......... 13

Nitrogen placement evaluation for winter wheat in three fallow tillage systems ....... 19

On the infiltration characteristics between tillage/residue soil condition and rainfall .......... 24

Tillage influence on soybean production .......... 26

Tillage, rotation and N effects on dryland corn production and nitrogen uptake in Northeastern Nebraska .......... 30

Fertilizer …


Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong Jan 1988

Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong

Grain and other field crops research reports

In the past couple of years research into lupins has increased substantially particularly in the fields of weed control, seeding rates, and control of diseases such as brown leaf spot and pleiochaeta root rot. This report is a summary of the lupin trials in the Lake Grace advisory area as well as a guide to better lupin farming.


Demographic Responses To The Chemical Control Of Doublegee, Dpird Jan 1988

Demographic Responses To The Chemical Control Of Doublegee, Dpird

Experimental Summaries - Plant Research

Trial No. 88WH58

Doublegee demography in cereal crops.

Objective: To measure reproductive output in relation to times of emergence and herbicide application.

Trial No. 88WH10

Growth of doublegee under summer irrigation.

Objectives: A major impediment to achieving biological control of any annual weed in the wheat belt is that the bicontrol agent must have a means of aestivation. Since the only insect to have been introduced to Australia for a the control of doublegee does not aestivate, it was thought that populations could be able to oversummer in irrigated doublegee standards. The aim of this study was to assess the …


Considerations In Breeding Endophyte-Free Tall Fescue Forage Cultivars, Jeffrey F. Pedersen, D. A. Sleper Jan 1988

Considerations In Breeding Endophyte-Free Tall Fescue Forage Cultivars, Jeffrey F. Pedersen, D. A. Sleper

Department of Agronomy and Horticulture: Faculty Publications

Breeding tall fescue (Festuca arundinacea Schreb.) cultivars that are free of the endophytic fungus Acremonium coenophialum Morgan-Jones and Gams [previously identified and referred to as Epichloe typhina (Fries) Tulasne] is necessary to improve animal performance. The techniques used in developing new cultivars are not greatly different from those used previously, with one exception. Prior to the evaluation of new tall fescue lines or populations, the endophyte needs to be eliminated from the seed or the plants. Several techniques utilizing aging, heat, or chemical treatment are being used to effectively accomplish this in the seed. Methods for permanently eliminating the endophyte …


Levels And Timing Of Nitrogen Fertilizer Applications For Tall Fescue In Central Alabama, J. W. Odom, Jeffrey F. Pedersen Jan 1988

Levels And Timing Of Nitrogen Fertilizer Applications For Tall Fescue In Central Alabama, J. W. Odom, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Tall fescue (Festuca arundinacea Schreb.), the most important cool season perennial pasture grass in the United States, is generally well adapted to the northern two-thirds of Alabama. Unfortunately, the most commonly grown tall fescue cultivar, Kentucky 31, is of northern origin and is dormant during the winter. To reduce this problem, AU Triumph was selected from Mediterranean germplasm. The Alabama Agricultural Experiment Station released this cultivar to growers in 1981. Compared to Kentucky 31, AU Triumph produces about 80 percent more forage during the winter and produces mature seed about 2 weeks earlier in the spring. Total annual forage production …


Direct Seeding Trees On Farmland In The Western Australian Wheatbelt, J P. Piggott, P H. Brown, M M. Williams Oct 1987

Direct Seeding Trees On Farmland In The Western Australian Wheatbelt, J P. Piggott, P H. Brown, M M. Williams

Resource management technical reports

Field and nursery experiments were conducted to determine suitable species, weed control methods, sowing times and seeding techniques. Sowing time was the most significant variable evident in the field experiments. Trees sown in the winter months of June and July out-performed later sowing times. Early sowing of trees in areas of low seasonal rainfall appears to offer considerable advantages for successful establishment over late sowing.


Intsormil Annual Report 1987, John M. Yohe, Timothy T. Schilling Jan 1987

Intsormil Annual Report 1987, John M. Yohe, Timothy T. Schilling

INTSORMIL Impacts and Bulletins

The Sorghum/Millet CRSP was initiated on July 1, 1979. This annual report covers the activities for program Year 8. Eight years of experience have reaffirmed the need for this type of research program aimed at relieving the constraints to improved sustainable sorghum/millet production in developing countries. The emphasis by the CRSP on development of collaborative linkages with national sorghum/millet research programs has been unique. Significant contributions have been made toward resolving constraint problems and enhancing the national program capability by strengthening its human resource base as well as the national institutional capability to conduct collaborative research. Thus, the CRSPs present …


Reproductive Biology Of Gorteria Personata, J. Dodd Jan 1987

Reproductive Biology Of Gorteria Personata, J. Dodd

Experimental Summaries - Plant Research

Trial 86MO3 and 86NO8

Loss of dormancy

Location: Moora and Meckering.

Gorteria shows germination characteristics typical of winter annuals, which lose primary dormancy during summer, germinate in autumn when sufficient moisture is available and exhibit cold-induced dormancy in winter.


The Economics Of Saltland Agronomy, John S. Salerian, Clive Malcolm, Eddie Pol Jan 1987

The Economics Of Saltland Agronomy, John S. Salerian, Clive Malcolm, Eddie Pol

Resource management technical reports

No abstract provided.