Cotton Report 1992
ABOUT THE COLLECTION
The Cotton Report is one of several commodity-based agricultural research reports published by the University of Arizona.
This report, along with the Forage and Grain Report, was established by Hank Brubaker, Extension Agronomist, after seeing a similar report published by Texas A&M University in the mid-1970’s.
The purpose of the report is to provide an annual research update to farmers, researchers, and those in the agricultural industry. The research is conducted by University of Arizona and USDA-ARS scientists.
Both historical and current Cotton Reports have been made available in the UA Campus Repository as part of a collaboration between the College of Agriculture and Life Sciences and the University Libraries.
Contents for Cotton Report 1992
- Weather Conditions during the 1991 Growing Season
- Cotton Crop Growth and Development Patterns
- The Effects of PIX Application Timing on Lint Yield and Growth and Development Parameters
- Effect of PIX (Mepiquat Chloride) on the Growth, Development, and Yield of Pima S-7 (P-69) and Deltapine (90) Cotton
- Late-Season PIX Treatment for Cotton Termination
- Short Staple Variety Demonstration Summary, Maricopa Agricultural Center, 1989-1991
- Short Staple Variety Demonstration, Pinal County, 1988-1991
- 1991 Yuma County Upland Cotton Variety Trial, Wayne Stuhr Farm - Wellton, AZ
- Short Staple Variety Demonstrations, Graham County, 1991
- Cotton Variety Trial, Safford Agricultural Center, 1991
- Short Staple Variety Trial, Cochise County, 1991
- Short Staple Variety Trials, Greenlee County, 1991
- Pima Cotton Improvement
- Pima Cotton Genetics
- The Use of AZSCHED to Schedule Irrigation on Cotton, Safford Agricultural Center - 1991
- Water Stress Effects on Pima Cotton Lint Yields Using Infrared Thermometry to Schedule Irrigations
- Irrigation Efficiencies, Nitrogen Applications, and Lint Yields of Upland Cotton Grown at the Marcopa Agricultural Center, 1991
- Community-wide Insect Management Program in Pima County, 1991
- IPM Cotton Projects, Safford Agricultural Center 1991
- Evaluation of Transgenic Cotton Lines for Resistance to Pink Bollworm and Leaf Feeding Lepidoptera
- Response of Nectaried and Nectariless Pima Cotton to Pink Bollworm
- Inundative Release of Trichogrammatoidea bactrae for Biological Control of Pink Bollworm
- Seasonal Dynamica of Sweetpotato Whitefly
- Sweetpotato Whitefly: Flight Activity, Effects of Wind Velocity, and Precopulatory Pairing Activity Patterns
- Insecticidial Control of the Sweet Potato Whitefly in Cototn
- Use of Treated-vial Technique to Determine Efficacy of Several Insecticides against the Sweetpotato Whitefly, Bemisia tabaci (Gennad.)
- Efficacy of the Insect Growth Regulator, Buprofezin and the Insecticide, Amitral against the Sweetpotato Whitefly on Cotton at Maricopa, AZ, 1991
- A Native Weed as a Trap Crop for Whiteflies in Cotton
- Leafminers, Liriomyza trifolii, on Cotton in Arizona
- Nitrogen Management Experiments for Upland and Pima Cotton, 1991
- Upland Cotton Resposne to Soil and Foliar Applies Potassium Fertilizer, 1991
- Cotton Yields: Nitrogen and Harvest Aid Effects
- Dissolved Nitrogen Compounds in Integrated Aquaculture Effluent
- Cottonseed Treatment Evaluations in Arizona, 1991
- Physiological Studies of Cotton Drought Tolerance
- The Arizona Cotton Advisory Program
- Revised Planting Window for Full Season Cototn Varieties
- Evaluation of Date of Planting and Irrigation Termination on the Yield of Upland and Pima Cotton
- Effects of Planting Date on the Yield of Cotton Varieties at Yuma, Arizona
- Plant Population Effects on Pima S-6 Lint Yield
- Cotton Row Spacing Studies, Safford Agricultural Center
- 1991 Cotton Replant Decisions, Safford Agricultural Center
- Defoliation of Pima Cotton, 1991
- Defoliation Research on Pima and Upland Cotton at the Maricopa Agricultural Center in 1991
- Defoliation Research on Pima and Upland Cotton at the Marana Agricultural Center in 1991
- Defoliation of Pima Cotton at 3000 Feet Elevation, Safford Agricultural Center, 1991
- Effect of Plant Water Status on Defoliation and Yield of Upland Cotton for Short-Season Production
- Effect of Plant Nitrogen Status on Defoliation of Short-Season Upland Cotton
Effect of Plant Nitrogen Status on Defoliation of Short-Season Upland CottonField studies have been conducted over a four year period at the Maricopa Agricultural Center to determine the influence of nitrogen (N) fertility level on the effectiveness of chemical defoliants for short- season cotton production. Excessive N resulted in dense foliage and cotton that was difficult to defoliate. When plants were deficient in N from mid-season to termination, defoliants were very effective, but lint yields were reduced. The effectiveness of defoliants decreased as the petiole NO₃-N content increased. The optimum fertility program for short-season cotton is one that provides sufficient N during the season to produce maximum lint yields, but allows the crop to become deficient in N at the end of the season, prior to chemical defoliation.
Effect of Plant Water Status on Defoliation and Yield of Upland Cotton for Short-Season ProductionA field study was conducted at the Maricopa Agricultural Center to determine the influence of plant water status at the time of defoliation on the effectiveness of defoliants and yield of short-season cotton. Irrigation termination dates of 14 and 26 August and 10 September were used to achieve different levels of plant water stress at the time defoliants were applied (19 September). Irrigation termination dates had no effect on seedcotton yield for cotton defoliated in September. As the period between the termination irrigation and the date of chemical defoliation was increased the effectiveness of defoliants was increased. CWSI and plant water potential measurements indicated that the irrigation termination dates resulted in large differences in plant water stress at defoliation time. There was a significant increase in the defoliation percentage as CWSI values increased (from 0.32 to 0.96) and water potential decreased (from -1.5 to -3.5 MPa). Short- season cotton (163 days) produced 4,396 lbs. seedcotton /A as compared to 5,299 lbs./A for a full-season crop (212 days).
Defoliation of Pima Cotton at 3000 Feet Elevation, Safford Agricultural Center, 1991A preliminary study of several defoliants and /or combinations was made on the Safford Agricultural Center. Even though conditions were less than ideal because of cool temperatures, acceptable defoliation occurred under several of the treatments. In fact, three of the treatments performed better than sodium chlorate, which is the predominant defoliant used in the area.
Defoliation Research on Pima and Upland Cotton at the Marana Agricultural Center in 1991A field study was conducted at the Marana Agricultural Center to evaluate the effectiveness of ground rig applied defoliant treatments on Pima and Upland cotton under cool weather conditions. Defoliants were slow acting at this location, however, all chemical treatments tested resulted in good defoliation 14 days after application.
Defoliation Research on Pima and Upland Cotton at the Maricopa Agricultural Center in 1991A field study was conducted at the Maricopa Agricultural Center to evaluate the effectiveness of selected defoliant treatments on Pima and Upland cotton under warm and cool weather conditions. In September tests, no defoliant treatment was effective in a single application. Upland cotton that was injured by frost in late October was difficult to defoliate in November tests. Pima cotton exhibited less frost injury than Upland and all defoliant treatments resulted in good defoliation in November.
Defoliation of Pima Cotton, 1991Four field experiments were carried out in several representative cotton producing areas of Arizona to evaluate the effectiveness of a number of defoliation treatments on Pima cotton. Somewhat variable but generally hot and dry conditions were encountered among the experimental locations in 1991 for treatment comparisons. It appears that consistencies in the effectiveness of several treatments for Pima defoliation offer a basis for further refinement of recommendations across the state.
1991 Cotton Replant Decisions, Safford Agricultural CenterEach planting season in the Safford valley there are fields that suffer stand reduction from adverse weather conditions. This study addresses some of the options and the economical effects from exercising these options on a field at the Safford Agricultural Center. References are made to work in California that have quantified the yield effect of stand reduction and chilling damage to cotton seedlings. This study shows that patience may pay better than rushing into the field to replant or rewater.
Cotton Row Spacing Studies, Safford Agricultural CenterA row spacing study was conducted at the Safford Agricultural Center from 1989 to 1991, evaluating the effects of 40 inch, 36 inch, 36-30 inch and 30 inch row spacing on Pima and upland cotton. The results of the study are not clear cut in favor of narrow or wide row cotton. Trends make it appear that narrow rows are more favorable for upland than Pima cotton varieties. Insufficient data is available at this point to make a firm recommendation.
Plant Population Effects on Pima S-6 Lint YieldA replicated field study was conducted at the Maricopa Agricultural Center in 1991 to investigate the effect of plant population density on Pima S-6 lint yield. Treatments ranged from a low of 10,465 plants per acre to a high of 65,000 plants per acre. There were no significant yield differences observed with populations between 17,000 plants per acre and 65,000 plants per acre. Significant yield decreases occurred when populations were reduced below 17,000 plants per acre.
Effects of Planting Date on the Yield of Cotton Varieties at Yuma, ArizonaA field experiment was conducted in Yuma, Arizona to evaluate the effects of planting date on cotton yields. Six Upland varieties were planted on 3 dates from 15 March to 24 April in 1991. Significant differences were found among varieties at the first planting date (15 March) with full season varieties yielding higher than medium and short season varieties. No differences were found among varieties at planting dates 8 April and 24 April. Significant differences were found among planting dates for all varieties. Weather conditions in March were abnormally cool and may have negatively influenced yields from the first planting date.
Evaluation of Date of Planting and Irrigation Termination on the Yield of Upland and Pima CottonFive field experiments were conducted at three locations in 1991 in Arizona to evaluate the response of Upland and Pima cotton to dates of planting and dates of irrigation termination. Planting dates ranged from as early as 2 April in the Yuma Valley (150 ft. elevation) to 14 May at Marana (2,000 ft. elevation). Dates of irrigation termination ranged from 8 August in the Yuma Valley to 24 September at Maricopa. Planting date was commonly a significant effect in these experiments, particularly with Pima cotton. Irrigationtermination results over three locations and three seasons show increases of approximately 50 to 100 lbs. lint /acre by extending later irrigations.
Revised Planting Window for Full Season Cototn VarietiesA heat-unit-based planting window was introduced in 1991 as a means of reducing early season problems with pink bollworm (PBW). Growers were encouraged to plant full season varieties when the annual heat unit (HU) accumulation ranged between 600 and 900 -- a window designed to ensure 75% suicidal emergence of PBW yet maintain acceptable yield levels. New research findings and a reexamination of past PBW emergence studies now support making an adjustment to the planting window. For 199Z the recommended planting window is 450 - 700 HUs after January 1.
The Arizona Cotton Advisory ProgramArizona Cooperative Extension produced and distributed weather -based Planting Date and Cotton Development Advisories for 8 cotton production areas (Marana, Litchfield Pk, Pinal Co., Parker, Safford, Yuma Valley, Dateland and Aguila) in 1991. Planting Date Advisories were distributed from mid - February through the end of April and stressed 1) planting full season cotton varieties according to heat unit accumulations rather than calendar date and 2) the importance of soil temperature to good germination. Cotton Development Advisories were distributed from early May through mid- September and provided growers updates on crop development, insects, weather and agronomy. The Cotton Advisory Program will continue in 1992 with the major change being an expansion in coverage to include Paloma, Queen Ck, and Mohave Valley.
Physiological Studies of Cotton Drought ToleranceWe evaluated an array of progeny of interspecific cotton crosses in the field. Significant water stress was placed on the plants in mid-summer by withholding water supplied by drip irrigation during plant development earlier in the season. A number of physiological measurements were carried out on selected individual plants of this population during the several week period of imposed drought stress. Overall results confirm that a large degree of variation exists within the population for all traits measured. Initial carbon isotope discrimination measurements suggest this trait may prove useful in estimating transpiration efficiency of cotton genotypes.
Cottonseed Treatment Evaluations in Arizona, 1991Field experiments were conducted at three locations in Arizona (Maricopa, Marana, Safford) to evaluate 12 cottonseed treatments on Upland cotton (G. hirsutum L.). Stand counts were taken to evaluate the effectiveness of each treatment. Statistical analysis showed no significant differences among the treatments used at the Marana location. Significant differences were found among the treatments used at the Maricopa and Safford locations.
Dissolved Nitrogen Compounds in Integrated Aquaculture EffluentIntegrated aquaculture utilizing pre- irrigation water will hypothetically increase the levels of dissolved nitrogen products in the resulting effluent. Research was performed to assess the levels of additional nutrients added. The results suggest however, that integrated aquaculture may reduce the amount of nitrogen as nitrate applied to the fields.
Cotton Yields: Nitrogen and Harvest Aid EffectsThe results of field studies with N rates from 0 to 336 kg/ha, in combination with two growth regulators, ethephon (Prep® ɑ-chloroethyl phosphonic acid, Rhone-Poulenc Ag Co., Research Triangle Parr NC) and thidiazuron (Dropp® N- phenyl -N' -1,2,3 -thiadiazol -5ylurea, Nor-Am Ag Prod. Inc., Naperville, IL). Results showed that sidedress applications of N (ammonium nitrate) to cotton did not influence the defoliation effects of ethephon and thidiazuron, or reduce number of immature green bolls at harvest. Under short-season conditions, sidedress N applications did not effect yields. Ethephon and thidiazuron at the rates tested did not affect cotton lint yields. Thidiazuron alone or in combination with ethephon resulted in high percentages of cotton defoliation.
Upland Cotton Response to Soil and Foliar Applied Potassium Fertilizer, 1991A single field experiment was conducted near Gila Bend, Arizona in 1991 to evaluate the effects of both soil and foliar applied potassium (K) fertilizersto Upland (Gossvpium hirsutum L.) cotton to a soil testing 315 ppm K (high). Soil applied K fertilizer at rates of 0, 75,150, and 225 lbs. K₂O/acre as K₂SO₄ were broadcast and preplant incorporated before listing. Foliar applications were made in all combinations with the various soil applied K treatments and consisted of four applications of 4.6 lbs. K₂O /acre as KNO₃ (10 lbs. KNO₃ /acre) over the first fruiting cycle, by a ground applicator with approximately 25 gallons per acre as carrier. No differences among treatments were detected by any plant growth measurement taken, plant tissue analyses, lint yield or lint quality determinations which were made over this experiment. Conclusions (preliminary) based upon these results indicate that K fertilization was not warranted under the conditions characterized in this single field experiment.
Nitrogen Management Experiments for Upland and Pima Cotton, 1991Two field experiments were conducted in Arizona in 1991 at two locations (Maricopa and Safford). The purposes of the experiments were to validate and refine nitrogen (N) fertilization recommendations for both Upland and Pima cotton. The experiments each utilized N management tools such as pre-season soil tests for NO₃⁻-N, in- season plant tissue testing (petioles) for N fertility status, and crop monitoring to ascertain crop fruiting patterns and crop N needs. Results at both locations revealed a strong relationship between the crop fruit retention levels and N needs for the crop. This pattern was further reflected in final yield analysis as a response to the N fertilization regimes used.
Leafminers, Liriomyza trifolii, on Cotton in ArizonaLiriomyza leafminers have occurred in Arizona for several years. It has only been recently that a new species, Liriomyza trifolii, has been reported on vegetable crops such as melons and lettuce. During the 1991 growing season, L. trifolii was observed causing damage to cotton for the first time in Central Arizona. Infestations occurring in Coolidge, had reached damaging levels and required control, whereas populations occurring in Yuma were very low. The impact of management and environmental factors responsible for the outbreaks of L. trifolii on cotton are discussed.