Abstract                                                                         Back to Table of contents

Cotton has an indeterminant growth habit and an extreme sensitivity to adverse environmental conditions which can result in excess fruit abscission. Because of these characteristics, during most of the time this plant has to assume simultaneously flowering, canopy and boll development, until any limiting factors (water, temperature, light or nutrient stress) occurs, producing shedding and limiting lint and seed yields. The effects of N, P and K nutrients on vegetative growth, flowering, fruiting and lint or seed production have often been described. Nevertheless the synchronism of these process implies that it is necessary to supply every nutrient throughout the growth cycle of cotton. Then the mineral nutrition of cotton depends both on the cotton roots ability to explore the soil and on the soil ability to supply N, P and K nutrients.

The exploration of a large volume of soils favours high nutrition in all elements. The failure in root growth can be put down to physical conditions, excess of water, plant diseases and also because of chemical factors: toxicity (aluminium in acid soils) or shortage of plant vigour like water stress, low temperature and solar radiation, bad sanitary conditions etc.

The soils N, P and K supplies are in dynamic equilibrium between available forms (dissolved and easily dissolved substances) and reserves which cannot be absorbed directly. These balances are linked to physical, biological and chemical conditions in soil.

The N, P and K in fertilizers are added to the soil mineral “pool”. Many documents present responses of cotton and/or soil to N, P and K fertilizers. However, there is a large response variability to fertilizers: variability between regions, years, sowing dates, etc.

The cotton price fluctuations and environment problems should encourage better management of fertilizer, using the physiological and agronomical knowledge of N, P and K dynamics. We must search for an economic optimum and take the long term future of the farm into account.  This management must be done firstly by cropping techniques to improve the root’s ability to explore the soil.

Fertilization must also be managed at the historical level. The cotton field benefits or suffers from the previous crop or fallow and from technical practices on the field. Fertilization of cotton also influences the following crops, the sustainability of the fields and pollution.

The fertilization must be managed at a geographical level. Nutrients transfer may occurs from some place in the landscape to another by wind, livestock, stream, harvest removals, etc. on the vertical axis, trees and some cover crops may absorb drained elements from deeper levels of soil and deliver them to the surface.

Then fertilization is now a systems problem and research has to quantify the relationships between all the factors of the fertilization and create models in order to help the farmers to manage their crop.


Agricultural science is currently changing rapidly.  For several years, it has been developing into an ecophysiology.  ECO because it takes into account what is happening within the natural environment and PHYSIOLOGICAL because attempts are being made to understand yield determination through increasingly fine-tuned analyses.  This change has been made possible through the extraordinary advances made in computerisation, which have enabled the modelling of relations and the development of yield determination models that take into account the crop system as a whole.  In fact, the plant and the field are immersed in a set of relations that have to be taken into account to provide farmers with fertilizer recommendations.  Consideration of economics in the advice given is also destined to develop.

Of course, this change is still new and not all the systems have been described, validated or quantified, but it is highly likely that as it proceeds it will completely transform how recommendations for farmers are established.

In many cases, the search for optimum yields has been superseded by that for a response to farmers’ economic and social requirements.

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Abstract                                                                         Back to Table of contents

A vision guidance system has been designed, built and commissioned which steers a tractor relative to the rows of a crop such as cotton.  It was required to be insensitive to additional visual “noise” from weeds, while tolerating the fading out of one or more rows in a barren patch of the field.  The system integrates data from several crop rows, testing for image quality.  At the same time, the data processing requirements have been limited by the use of frame-sequential strategies to reduce the image space which must be processed.  The current prototype employs an embedded 386 PC notebook computer and shows great promise of cost effective commercial exploitation.

Experimental results are reported and further sensing systems are explored to enhance performance in difficult environments.


A program of research combining theory and experimentation has resulted in the verification of a practical guidance system, despite early limitations of very meagre resources.  Now that adequate funding has been allocated, the system can be prototyped to professional standards and its performance enhanced to achieve industry acceptance.

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Contents of the WCRC1, in Brisbane, Australia (1994)


Opening Address (The Honourable Bill Hayden AC
Governor-General of the Commonwealth of Australia)

Future Role of Cotton Research in Developing Countries (Barbosa, S.)


Plant monitoring and growth regulators

Predicting Yield Responses of Cotton to Growth Regulators (Constable, G.A.)

Use of Growth Regulators in Cotton Production (Cothren, J.T.)

The Use of Plant Monitoring Techniques as an Aid in Determining Mepiquat Chloride Rates in Rain-fed Cotton (Edmisten, K.L.)

Effects of PGR-IV on the Growth and Yield of Cotton: A Review (Oosterhuis, D.M.)

Virtual Cotton: A New Tool for Research, Management and Training (Room, P.M. & Hanan, J.S.)

Imperial Valley Cotton Fields Surveyed with Plant Mapping (Wrona, A.F. & Kerby, T.)

Irrigation and water relations

Near Real-Time Irrigation Scheduling on Cotton Using Azsched Software (Clark, L.J., Slack, D.C., Fox Jr., F.A. & Martin, E.C.)

Yield Potential of Cotton Under Drip Irrigation in South Africa (Dippenaar, M.C., Barnard, C. & Pretorius, M.M.)

The Physiology of Cotton Water Use Efficiency (Gerik, T.J., Landivar, J.A. & Faver, K.L.)

The Principles of Cotton Water Relations and Their Application in Management (Hearn, A.B.)

Improvements in Water Use Efficiency in Irrigated Cotton: Choices in Systems and Management (Hutmacher, R.B., Phene, C.J., Davis, K.R., Detar, W.R. & Ayars, J.E.)

Plant Responses to Late Season Water Deficits in Acala Cotton Cultivars (Munk, D.S., Grimes, D.W. & Kerby, T.A.)

Influence of Salinity on Reproductive Growth of Three Egyptian Cotton Cultivars (Nawar, M.T., Zaher, A.M., El-Sahhar, K. & Abdel-Rahim, S.A.

Crop nutrition

Nitrogen, Phosphorus and Potassium Availability in the Soil, Physiology of the Assimilation and Use of These Nutrients by the Plant (Bisson, P., Cretenet, M. & Jallas, E.)

Sowing Date and Nitrogen Application Effects on Petiole Nitrate Content in Cameroon (Ekorong Á Moute, J.)

Foliar Application for Yield and Quality of Cotton Grown on Kampang Saen Soil in Thailand (Kesawapitak, P., Boonyong, B., Somnus
P., Sangsila, S. & Jongruaysup, S.)

Potassium Nutrition of Cotton (Oosterhuis, D.M.)

Response of Cotton to NPK Fertilization – The Greek Experience (Setatou, H.B. & Simonis, A.D.)

Effect of Foliar Applied Nitrogen and Potassium on Cotton in the San Joaquin Valley of California (Weir, B.L. & Roberts, B.)

Soil structure

Managing Soil Mechanical Stresses for Cotton Production (Agrawal, R.P.)

Problems Associated with Soil Structural Assessment on Vertisols Used for Irrigated Cotton Production (Greenhalgh, S.E., McKenzie, D.C.,
Melville, G. & MacLeod, D.A

Compaction in Cotton Beds – Measurement, Modelling and Management (Kirby, J.M. & Blunden, B.G.)

The Optimisation of Soil Structure for Cotton Production (McGarry, D.)

Soil Management Options for Cotton-Based Farming Systems in Swelling and Non-Swelling Soils (McKenzie, D.C.)

Structure Repair with Wet/Dry Cycles in a Cotton Soil (Pillai-McGarry, U., Sarmah, A.J. & McGarry, D.)

Determining Non-Erosive Velocities for Design of Contour Banks (Titmarsh, G. & Loch, R.)

Weed control

Future Weed Control Systems for Conservation Tillage Cotton in the Southeastern USA (Patterson, M.G.)

Nightshade Control with Phrithiobace (Staple) in California (Vargas, R. & Wright, S.)

Metham in Cotton (Wright, S.D., Vargas, R., Jimenez Jr., M.R. & Duvall, T.M.)

Seed science

Effects of Soaking on the Germination Characteristics and Mineral Leakage of Cotton (Gossypium hirsutum L.) Seed (Gençer, O., Wali, S., Düzenl, S. & Efe, L.)

The Effect of Storage and Radiation on Cotton Seed for Some Yield Component (Raafat, M.A.A.)

Farming systems

An Automatic Steering System for the Inter-Row Crop Cultivation of Cotton (Billingsley, J. & Schoenfisch, M.)

Recovery of Cotton (Gossypium hirsutum) from Intercropping Suppression by Beans (Phaseolus vulgaris) (Elobu, P., Orwanga, J.F., Ocan, J. & Opolot, G.W.)

The Use of Cotton Stalks and Cotton Ginning Trash as Feedstocks for Ethanol Fuel Production (Fraser, K.I., Gould, N.S. & Holmes, A.J.)

Management of Lablab purpureus L. Residues in Cotton-Based Farming Systems and Consequent Effects on Properties of a Typic Pellustert (Hulugalle, N.R., Larsen, D.L. & Henggeler, S.)


Diseases and breeding for disease resistance

Mechanisms of Disease Resistance in Gossypium Species and Variation in Verticillium dahliae (Bell, A.A.)

Breeding for Resistance to Bacterial Blight of Cotton in Relation to Races of the Pathogen (El-Zik, K.M. & Thaxton, P.M.)

Loss in Seed Cotton Yield Due to Fusarium Wilt in Sudan Gezira (Ibrahim, G. & Fadl Alla, A.S.)

Development of MAR Cotton Germplasm with Morphological Mutant Traits (Thaxton, P.M. & El-Zik, K.M.)

Fibre quality

Quality Assessment for Breeding Egyptian High Quality Cotton Varieties (Abdel-Salam, M.E.)

Agronomic Management of Extra Fine Cotton for Higher Grades in Egypt (El Rifai, G.)

Crystallinity, Crystallite Size, Fine Structural and Physical Fibre Properties at Two Fibre Maturity Levels in Two Egyptian Cotton Cultivars (Nawar, M.T., Khalifa, B.A. & Al-Ganainy G.)

Development of Medium Staple High Strength Cotton Suitable for Rotor Spinning Systems (Patil, N.B. & Singh, M.)

High Speed Measurements of Strength and Elongation (Taylor, R.A.)

 Genetics, biotechnology and wild species

Risk of Escape of Transgenes from Cotton into Natural Populations of Australian Gossypium Species (Brown, A.H.D., Hurka, H., Craven, L.A. & Grace, J.P.)

The Australian Wild Species of Gossypium (Craven, L.A., Stewart, J. McD., Brown, A.H.D. & Grace, J.P.)

The Heritability of Yield, Yield Components and Fibre Technological Properties in Partial Diallel Hybrids of Upland Cotton (Gossypium hirsutum L.) Varieties in Southeastern Anatolia Region of Turkey (Gençer, O. & Kaynak, M.A.)

A Brief Review of Cotton Genetic Research in China (Jinfa, Z. & Jizhong, S.)

Inheritance and Genetic Effect of Cleistogamy in Upland Cotton (Jinfa, Z., Jizhong, S. & Jinlan, L.)

Progress in Genetic Engineering of Cotton for Fiber Modifications (John, M.E.)

Studies of Quantitative Characters in Upland Cotton (Gossypium hirsutum L.) (Kapoor, C.J).

Identification of the Karyotype of Gossypium bickii Prokh (Kunbo, W., Maoxue, L., Guoli, S. & Xiangdi, Z.)

Use of Molecular Markers in Cotton Breeding (Meredith Jr., W.R.)

Interspecific Hybridization and Synthesis of Allotetraploid Genotypes in Cotton (Randhawa, L.S. & Dhillon, J.)

Potential for Crop Improvement with Exotic Germplasm and Genetic Engineering (Stewart, J. McD.)

Screening of Somatic Mutants for Resistance to Verticillium Wilt in Gossypium hirsutum L. (Xianlong, Z., Mingjing, Y. & Jizhong, S.)

Hybrid vigour

Hybrid Cotton: Results and Prospects (Basu, A.K.)

Heterosis Breeding for Crossing Present Yield Barriers in Cotton (Randhawa, L.S. & Singh, T.H.)

Performance of F1 and F2 Hybrids Between Australian and USA Commercial Cotton Cultivars (Reid, P.E.)

Host plant resistance to insect pests

Volatile Terpenes and Terpenoid Aldehydes in Australian-Grown Gossypium hirsutum L. Cultivars and Lines (Benson, C.G., Fitt, G.P., Leach, D.N., Mares, C.L., Naiker, M.N. & Wyllie, S.G.)

Induction of Somatic Embryogenesis in a Range of Cotton Cultivars (Dongre, A.B., Nandeshwar, S.B., Kranthi, K.R., Kranthi, S. & Basu, A.K.)

Host Plant Resistance to Insects in Cotton (Jenkins, J.N.)

New Cotton Varieties for IPM (Mursal, I.E.J.)

Varietal improvement

Cotton Research and Production in Bangladesh (Rahman, M.A.)

Progress with Varietal Improvement in CIRAD (Hau, B.)

New Horizons in Lint Percentage in Pakistan (Khan, M.D., Khan, W.S., Ahmad, M. & Ibrahim, M.)

Performance of Early and Late Maturing Varieties of Cotton (Gossypium hirsutum L.) in the Marginal Rainfall Areas of Central and Eastern Kenya (Ngigi, R.G.)

Commercial Utilisation of the Okra Leaf Mutant of Cotton – The Australian Experience (Thomson, N.J.)


Ecology/integrated pest management

Impact of Boll Weevil Eradication on Cotton Production and Insect Management in Virginia and North Carolina, USA (Bacheler, J.S.)

Thai Cotton Growers Still Far Away from IPM: Contribution of Systems Approach to a Better Understanding of Farmers’ Practices (Castella, J., Swangsri, W. & Kimnarux, J.)

The Use of Pheromones to Control Three Species of Bollworm in Pakistan (Chamberlain, D.J., McVeigh, L.J., Critchley, B.R., Hall, D.R. & Ahmad, Z.)

Migration of Cotton Pests:  Patterns and Implications for Management (Gregg, P.C.)

Area-Wide Management of Heliothis/Helicoverpa in the Delta of Mississippi (Hardee, D.D. & Bell, M.R.)

Chemical Characterisation of Cotton Insect Honeydew and Elimination of Stickiness of Honeydew-Contaminated Lint (Hendrix, D.L., Perkins Jr., H.H. & Valaitis, A.)

Synthetic Pyrethroid Induced Cotton Plant Leaf Tissue Morphological Changes and Incidence of Bemisia tabaci (Ilyas, M.D., Puri, S.N., Lavekar, R.C., Butler Jr., G.D. & Henneberry, T.J.)

The Use of Baculoviruses in Cotton IPM (Jones, K.A.)

Comparative Information on the Local Abundance of Two Pests, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and Aphis gossypii (Glover) (Homoptera: Aphididae) and Selected Predators on Cotton in Eastern Tanzania (Kabissa, J.C.B.)

Integrated Pest Management in Cotton (de B. Lyon, D.J.)

Impact of the Introduction of the Cotton Boll Weevil in Brazil(Ramalho, F.S. & Santos, R.F.)

Modelling Pheromone Use for Pink Bollworm Control in Egypt (Russell, D.A., Radwan, S.M., El-Deeb, Y.A. & Mahmoud, H.M.)

Management  of the Cotton Boll Weevil with Attract-and-Kill-Devices (Smith, J.W., McKibben, G.H., Villavaso, E.J., McGovern, W.L. & Jones, R.G.)

Assessing Population Structure in the Cotton Bollworm, Helicoverpa armigera (Lepidoptera:  Noctuidae), Using Variation in the A+T-Rich Region of Mitochondrial DNA (Spackman, M.E. & McKechnie, S.W. )

Pest Models for Decision Support – Development and Applications (Sterling, W.)

Host Resistance to the Leafhopper, Amrasca devastans (Distant) in Cotton, Gossypium spp.(Uthamasamy, S.)

Ecological Attributes of Major Cotton Pests:  Implications for Management (Vaissayre, M.)

An Integrated Cotton Insect Pest Management System for Cotton-Wheat Intercropping in North China (Xia, J.Y.)

Insecticides/insecticide resistance management

Pymetrozine (CGA 215,944) – A Novel New Control for Sucking Pests in Cotton (Allemann, D.V., Robinson, S.W. & Flückiger, C.R.)

Insecticide Resistance in Helicoverpa armigera (Hübner):  Status and Prospects for its Management in India (Armes, N.J., Jadhav, D.R. & Lonergan, P.A.)

Fipronil:  A New Soil and Foliar Insecticide for Cotton (Hope, J.H.)

Insecticide Resistance Management as a Part of an IPM Strategy in Israeli Cotton Fields (Horowitz, A.R., Forer, G. & Ishaaya, I.)

Status of Tobacco Budworm Pyrethroid Resistance in Mexico (Martínez-Carrillo, J.L.)

Insecticide Resistance in Major Cotton Pests Worldwide:  Incidence, Mechanisms and Management (Plapp Jr., F.W., Kanga, L.H.B. & Karunaratne, K.)

Problems and Prospects of Management of Insecticide Resistance in Helicoverpa armigera (Hübner) in India (Regupathy, A.)

Cotton Pest Control Problems in Andhra Pradesh, India:  Optimising Pest Management Options for a More Sustainable Approach to Cotton Cultivation  (Venugopala Rao, N., Rajasekhar, P., Venkataiah, M. & Rama Rao, B.)

Novel Biological and Conventional Insecticides:  What’s New? (Watkinson, I.A.)

Development of an Insect Specific Fungus (Naturalis-L®) for Control of Cotton Insects (Wright, J.E.)

Pesticide application and the environment

Controlled Environment Study of the Degradation of Endosulfan in Soils (Ghadiri, H., Rose, C.W. & Connell, D.W.)

The Fate of Endosulfan Sprayed on Cotton (Kimber, S.W.L., Southan, S.K., Ahmad, N. & Kennedy, I.R.)

Development of Laboratory and Field Elisa Tests for Detection of Endosulfan in Water and Soil (Lee, N., Skerritt, J.H., Kennedy, I.R., McAdam, D.P., Beasley, H.L. & Hill, A.S.)

Increased Deposition of Insecticide Using Turbulent Air Assistance (Manor, G., Geva, A. & Tabac, S.)

Effective Spray Coverage Measuring Procedures (Manor, G., Jarvis, L.R. & Fielke, J.M.)

The Breakdown of Lambda-Cyhalothrin in Cotton-Growing Soil (Wang, S. & Kennedy, I.R.)


Abstract                                                                         Back to Table of contents

Soil mechanical stresses are detrimental to root and shoot growth in cotton when threshold values are exceeded.  Soil surface, mechanical stresses are manifested either as crusts or seals formed when rain or irrigation is followed by rapid drying, while at shallow depths a dense hard layer is formed due to either clay accumulation or calcification. Cotton seedling emergence was reduced from 58 to 10% when surface crust strength increased from 0.25 to 1.20 kg cm-2 in a sandy loam soil. Mechanical disruption of soil crust and seedline mulch application with farm yard manure (FYM) overcame the adverse effect of surface mechanical stresses on seedling emergence. A 5 cm thick layer of about 1.9 Mg m-2 at 15 to 20 cm depth decreased the plant height, root growth and yield of seed cotton. The growth of the tap root completely ceased when it encountered the dense layer and reduction in yield was about 16%. Deep tillage alleviated the adverse effect of a dense layer at shallow depths.


Surface and sub-surface mechanical impedance reduced seedling emergence, growth and yield of cotton. Seedline mulch with FYM, mechanical breaking and deep tillage is useful for managing soil mechanical stresses and for increasing cotton yield.

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