CHARACTERIZATION OF COTTON SOIL-PLANT-WATER RELATIONS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0213443
• Project Start Date: Jul 1, 2008
• Project End Date: Sep 30, 2012
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF ARIZONA
888 N EUCLID AVE
TUCSON,AZ 85719-4824

Performing Department
Soil, Water & Environmental Science

Non Technical Summary
In the desert Southwest of the U.S., water is commonly recognized as the most critical limiting factor in crop production systems. The latest Arizona Water Map reports that agriculture accounts for 68% of our state's water use. For Maricopa, Pinal and Pima counties, cotton accounts for the most cropland acreage. It also accounts for the most water use of all crops. In spite of rapid urban growth, cotton will play a key role in Arizona's water management for the foreseeable future due to the following: state and city policies have supported open space, sewage sludge can be responsibly disposed of using a cotton rotation, biotechnology makes it possible for cotton to co-exist near urban housing, tribal water right settlements, a generous farm policy towards cotton, and economically attractive recharging through agriculture. However, the question of how to best use a very limited water supply in a cotton production system has yet to be addressed. The need to address this question is also evidenced by the fact that some proposed drought management plans are calling for water allocations to agriculture based on crop consumptive use data. Thus, an understanding of crop water requirements and crop evapotranspiration (ET) is very important.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
102	1710	2050	100%

Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships;

Subject Of Investigation
1710 - Upland cotton;

Field Of Science
2050 - Hydrology;

Keywords

crop coefficients for cotton

cotton crop water use

cotton water use efficiency

capacitance probes

Goals / Objectives
1. Measure cotton crop water use by measuring soil water depletion for each in-season irrigation interval. 2. Develop cotton crop coefficients (Kc) as a function of stage of growth and heat unit (HU) accumulations. 3. Develop information that can be used to evaluate a crop-water production functions for cotton in Arizona (lint yield=f(water inputs and crop-water use)). 4. Evaluate the use of capacitance probes to measure volumetric water content and soil water dynamics.

Project Methods
Field experiments will be conducted at UA Maricopa Ag Center with the objective of evaluating the effects of two irrigation management regimes in terms of plant-water use patterns among all stages of growth and lint yield of an Upland cotton(Gossypium hirsutum L.)variety. The experimental design will be a randomized complete block design with 3 replications. Crop areas will be dry planted and watered up in early April. Plant measurements will be collected from each treatment on a 21 day interval to determine stage of growth, vigor, and N fertility status. Measurements include: plant height, number of mainstem nodes, first fruiting branch, number of aborted sites, number of nodes above top fresh flower, canopy closure, and number of blooms per unit area. Climatic conditions will be monitored daily using an AZMET station. The AZMET station determines hourly temperature and HU accumulations(86/55F thresholds).Daily HU accumulations are summed up from time of planting and reported as HUAP. AZMET also provides daily ETo data. Irrigations will be terminated to provide adequate soil water to mature the crop set through the primary fruiting cycle. The crop will be mechanically harvested and lint turnout estimates will be made using sub-sample analyses. The first treatment(I-1)will provide adequate plant-available water throughout the growing season to avoid plant water stress. The second treatment(I-2)will receive one-half the irrigation provided in I-1 with the intention of imposing substantial water stress. Irrigations will provide adequate conditions for I-1 plots by irrigating at 40-45% MAD which will be determined by projections using AZMET Eto estimates and directly checking soil moisture content on a regular basis. Irrigation applications will provide full replenishment of the depleted soil profile of the I-1 treatment areas which will be determined approximately 1 hour before irrigation begins by use of the volumetric water(θv)content readings that will be taken prior to irrigation. During the growing season θv content readings will be made through each irrigation cycle by a neutron probe, moisture meter to 120 cm by 10 cm increments. θv readings will be taken immediately before I-1 irrigations and 24 hours after irrigation for all areas,including I-2 areas. Neutron probe access tubes will be placed in the upper, middle, and lower 1/3 zones of the irrigation runs. Capacitance probes will be placed in direct proximity to each neutron probe access tube. Capacitance probes provide sensor measurements on 10 cm increments to a 120 cm and read in 15 minute intervals. This array of neutron probe access tubes and capacitance probes will provide the capacity to calibrate the capacitance probes to θv readings. The capacitance probes will be calibrated to θv values by use of the neutron probe data conversions to θv and regression analysis of the companion data. Soil samples will be collected pre-season for the area and caution will be given to the soil salinity. From the field data, Kc values were calculated using measured soil-water depletions for each irrigation interval and standard reference ETo values taken from AZMET.

Progress 07/01/08 to 09/30/12

Outputs
Target Audience:Target audiences include other members of the scientific community and also people from industry and the crop production communities in arid and semi-arid regions. This information is also valuable in the context of communicating science-based crop water relations in arenas where policy and resource management issues are being addressed. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Desert Turf School. Characteristics of Desert Soils Fertility and relation to turfgrass nutrition Presented at Tucson, AZ on 1/6/2009. (100%). Beltwide Cotton Conference. Evaluation of Residual Nitrogen Effects on Irrigation Cotton Presented at San Antonio, Texas on 1/7/2009. Manejo del Algodonero en el Valle de Mexicali. Fertilizacion en Algodon Presented at Mexicali, Mexico on 1/21/2009. (Cotton management in the Mexicali Valley - Cotton Fertilization). 2009 Southwest Ag Summit. Fertilizer and Water Management for Cotton in Arizona Presented at Yuma, AZ on 3/11/2009. (100%). Chile Mechanization Working Group. Using Heat Unit Tracking to Predict Chile Growth and Manage Inputs Presented at Deming, NM on 6/23/2009. (100%). SAHRA Annual Meeting. Climate, Water and Land Cover Change in a Non-Stationary World Managing Agricultural Systems with Chris Scott, Chris Udall, Steven Bales, George Frisvold Presented at Tucson, AZ on 9/23/2009. (25%). Simposium Internacional De Agricultura Ecologica (International Symposium on Organic Farming). Factores de agronomia para el desarrollo de sistemas de produccion de cultivos sostenibles en regiones aridas (Agronomic factors for the development of sustainable crop systems in arid regions). Presented at Cd. Obregon, Sonora, Mexico on 9/30/2009. Simposio Internacional Nutricion Vegetal. Recuperacion de suelos y/o sustratos afectados por factores inductores de estres en los cultivos (International Vegetable Nutrition Symposium. Soil improvement for factors affecting crop stress). Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. Simposio Internacional Nutricion Vegetal. Efectos de la fertilizacion sobre el medio ambiente y la calidad de los alimentos. (International Vegetable Nutrition Symposium. Effects of fertilization on crop and environmental quality). Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. (100%). Simposio Internacional Nutricion Vegetal. Desarrollo De Sistemas Agricola Sustentable por Regiones Aridas Y Semiaridas Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. Conferencias sobre el Cultivo de Esparrago. Principios para el manejo de nutrientes en esparrago de riego (Asparagus Production Conference. Principles of nutrient management for irrigated asparagus). Presented at Mexicali, Mexico on 10/16/2009. (100%). XL Aniversario Del Instituto De Ciencias Agricolas. Desarrollo De Sistemas De Produccion De Cultivos Sustentables En Regiones Aridas Y Semiaridas (Institute of Agricultural Science Anniversary Conference. Development of Sustainable Crop Production Systems in arid and semi-arid regions). Presented at Mexicali, Mexico on 10/29/2009. (100%). How have the results been disseminated to communities of interest?The results from this work addressing crop-water use requirements has been used in the development and delivery of many documents and presentations at producer and land/water management oriented meetings. Thus, the information is critically important in addressing programs with the objective of improving crop water-use efficiency in the desert Southwest. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Field experiments were conducted at the University of Arizona Maricopa Agricultural Center investigating soil- plant-water relations in an irrigated cotton (Gossypium hirsutum L.) production system. Current guidelines for the management of irrigation for cotton production systems in the desert Southwest utilize parameters that have not been thoroughly validated. The objective of this project was to develop an accurate water balance in a furrow-irrigated cotton production system and evaluate the accuracy of the crop coefficients that are currently available through the University of Arizona Meteorological Network (AZMET). Measurements of water application rates were taken with each irrigation event. In- season soil-water measurements were made prior to and immediately following each irrigation event by use of neutron attenuation to a depth of four feet (approximately 120 cm). Soil-water depletion rates were compared to crop ET estimates provided by AZMET. In-season crop monitoring was conducted and final lint yield was determined. Fiber quality was determined by HVI analysis. Results provide a thorough characterization of the soil-plant system under study and indicate soil-water depletion rates compare favorably with the AZMET crop ET estimates. Accordingly, crop coefficients (Kc) calculated from the data derived from this experiment were also close to the Kc values that have been developed and used in the AZMET system.

Publications

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Desert Turf School. Characteristics of Desert Soils Fertility and relation to turfgrass nutrition Presented at Tucson, AZ on 1/6/2009. (100%). Beltwide Cotton Conference. Evaluation of Residual Nitrogen Effects on Irrigation Cotton Presented at San Antonio, Texas on 1/7/2009. Manejo del Algodonero en el Valle de Mexicali. Fertilizacion en Algodon Presented at Mexicali, Mexico on 1/21/2009. (Cotton management in the Mexicali Valley - Cotton Fertilization). 2009 Southwest Ag Summit. Fertilizer and Water Management for Cotton in Arizona Presented at Yuma, AZ on 3/11/2009. (100%). Chile Mechanization Working Group. Using Heat Unit Tracking to Predict Chile Growth and Manage Inputs Presented at Deming, NM on 6/23/2009. (100%). SAHRA Annual Meeting. Climate, Water and Land Cover Change in a Non-Stationary World Managing Agricultural Systems with Chris Scott, Chris Udall, Steven Bales, George Frisvold Presented at Tucson, AZ on 9/23/2009. (25%). Simposium Internacional De Agricultura Ecologica (International Symposium on Organic Farming). Factores de agronomia para el desarrollo de sistemas de produccion de cultivos sostenibles en regiones aridas (Agronomic factors for the development of sustainable crop systems in arid regions). Presented at Cd. Obregon, Sonora, Mexico on 9/30/2009. Simposio Internacional Nutricion Vegetal. Recuperacion de suelos y/o sustratos afectados por factores inductores de estres en los cultivos (International Vegetable Nutrition Symposium. Soil improvement for factors affecting crop stress). Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. Simposio Internacional Nutricion Vegetal. Efectos de la fertilizacion sobre el medio ambiente y la calidad de los alimentos. (International Vegetable Nutrition Symposium. Effects of fertilization on crop and environmental quality). Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. (100%). Simposio Internacional Nutricion Vegetal. Desarrollo De Sistemas Agricola Sustentable por Regiones Aridas Y Semiaridas Presented at Guadalajara, Jalisco, Mexico on 10/8/2009. Conferencias sobre el Cultivo de Esparrago. Principios para el manejo de nutrientes en esparrago de riego (Asparagus Production Conference. Principles of nutrient management for irrigated asparagus). Presented at Mexicali, Mexico on 10/16/2009. (100%). XL Aniversario Del Instituto De Ciencias Agricolas. Desarrollo De Sistemas De Produccion De Cultivos Sustentables En Regiones Aridas Y Semiaridas (Institute of Agricultural Science Anniversary Conference. Development of Sustainable Crop Production Systems in arid and semi-arid regions). Presented at Mexicali, Mexico on 10/29/2009. (100%). PARTICIPANTS: The results from this work addressing crop-water use requirements has been used in the development and delivery of many documents and presentations at producer and land/water management oriented meetings. Thus, the information is critically important in addressing programs with the objective of improving crop water-use efficiency in the desert Southwest. TARGET AUDIENCES: Target audiences include other members of the scientific community and also people from industry and the crop production communities in arid and semi-arid regions. This information is also valuable in the context of communicating science-based crop water relations in arenas where policy and resource management issues are being addressed. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The results from this work addressing crop-water use requirements has been used in the development and delivery of many documents and presentations at producer and land/water management oriented meetings. Thus, the information is critically important in addressing programs with the objective of improving crop water-use efficiency in the desert Southwest.

Publications

• Efectos de la fertilizacion sobre el medio ambiente y la calidad de los alimentos. Simposio Internacional Nutricion Vegetal. (Fertilization effects on crop and environmental quality. International Vegetable Nutrition Symposium.) Recuperacion de suelos y/o sustratos afectados por factores inductores de estres en los cultivos. Simposio Internacional Nutricion Vegetal Published. (100%). (Soil improvement of factors that induce crop stress. International Vegetable Nutrition Conference. Desarrollo De Sistemas Agricola Sustentable por Regiones Aridas Y Semiaridas. Simposio Internacional Nutricion Vegetal Published. (Development of sustainable agricultural systems in arid and semi-arid regions. International Vegetable Nutrition Conference). Evaluation of Residual Nitrogen and Water Effects on Irrigation Cotton. Beltwide Cotton Conference. San Antonio, TX, January 7, 2009. Published. (100%). Fertigation. Silvertooth, JC. 2009. Fertigation. Farming Outlook. September, pp 17-26. Published. (100%).

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Field experiments were conducted at the University of Arizona Maricopa Agricultural Center investigating soil-plant-water relations in an irrigated cotton (Gossypium hirsutum L.) production system. Current guidelines for the management of irrigation for cotton production systems in the desert Southwest utilize parameters that have not been thoroughly validated. The objective of this project was to develop an accurate water balance in a furrow-irrigated cotton production system and evaluate the accuracy of the crop coefficients that are currently available through the University of Arizona Meteorological Network (AZMET). Measurements of water application rates were taken with each irrigation event. In-season soil-water measurements were made prior to and immediately following each irrigation event by use of neutron attenuation to a depth of four feet (approximately 120 cm). Soil-water depletion rates were compared to crop ET estimates provided by AZMET. In-season crop monitoring was conducted and final lint yield was determined. Fiber quality was determined by HVI analysis. Results provide a thorough characterization of the soil-plant system under study and indicate soil-water depletion rates compare favorably with the AZMET crop ET estimates. Accordingly, crop coefficients (Kc) calculated from the data derived from this experiment were also close to the Kc values that have been developed and used in the AZMET system. PARTICIPANTS: J.C. Silvertooth, University of Arizona Roberto Soto-Ortiz, Universidad de Baja California Autonoma D.L. Silvertooth, University of Arizona P.W. Brown. University of Arizona TARGET AUDIENCES: Crop production managers (growers and consultants), irrigation district managers, educational programs. PROJECT MODIFICATIONS: This information is allowing us to evaluate and update crop water management guidelines in the desert Southwest.

Impacts
This information is being used to evaluate our cotton crop water management guidelines in the desert Southwest.

Publications

• J.C. Silvertooth, D.L. Silvertooth, P.W. Brown, and R. Soto-Ortiz. 2008. Evaluation of Soil-Plant-Water Relations in Irrigated Cotton. Beltwide Cotton Research and Production Conference. Nashville, TN.