Cotton Report 1990
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 1990
- Controlling Purple and Yellow Nutsedge with Postemergence Applications of EPTC
- Potential Injury to Rotational Crops Following Single or Multiple Applications of Bladex to Cotton 3
- Evaluation of Date of Planting and Irrigation Termination on the Yield of Upland and Pima Cotton
- Effect of Irrigation Termination Date on Defolation and Yield of Upland Cotton for Short-Season Production
- Effects of Irrigation Termination Date on a Medium Maturity Type Upland Cotton
- Defolation of Pima Cotton, 1989
- Defolation Research on Pima Cotton at the Maricopa Agricultural Center in 1989
- Interaction of Pima Cotton Defoliation and Crop Water Stress Index
- Defoliation Research on Upland Cotton at the Maricopa Agricultural Center in 1989
- Effect of Plant Nitrogen Status on Effectiveness of Pix and Defoliants for Short-Season Cotton Production
- Effects of Date of Planting on the Yield of Four Cotton Varieties at Yuma, Arizona
- ABA and Auxin Contents of Squared and Flowers in Relation to Water Deficit Stress and Subsequent Young Boll Shedding
- PIX Multiple Application Evaluations in Arizona on Upland and Pima Cotton, 1989
- A Study of PIX Rates across CaZa and Triggrr on Long and Short Staple Cotton, Safford Agricultural Center, 1989
- Influence of Multiple Applications of PIX on Long and Short Staple Cotton, Safford 1989
- Plant Growth Regulator Research on Upland Cotton at the Maricopa and Marana Agricultural Centers in 1989
- Short Staple Variety Trial, Cochise County, 1989
- Cotton Variety Trial, Safford Agricultural Center, 1989
- Short Staple Demonstrations, Graham County, 1989
- Short and Long Staple Variety Trials, Greenlee County, 1989
- Short Staple Variety Demonstration, Yuma County, 1989
- Short Staple Variety Demonstration, Maricopa Agricultural Center, 1989
- Short Staple Variety Demonstrations, Pinal County, 1989
- Cotton Variety Trial, Mohave Valley, 1989
- Regional Variety Tests
- Pima Cotton Improvement
- Pima Gotton Genetics
- A Sensor System for Monitoring Cotton Water Status
- Pima Cotton Irrigation Scheduling Using Infrared Thermometers and the Crop Water Stress Index
- Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics
- Irrigation Scheduling on Long and Short Staple Cotton, Safford Agricultural Center, 1989
- Response of Texas Root Rot to a Soil Sterilant the Second Year After Application in Marana, 1989
- Effect of Harvest Date on Aflatoxin Contamination in the Yuma Valley
- The Effect on Yield of Cotton Due to Incidence and Severity of Black Root Rot Caused by Thielaviopsis Basicola
- Suppresion of Inflection of Cotton Seedlings by Rhizoetonia Solani in the Presence of Thielaviopsis Basicola, the Causal Agent of Black Root Rot
- Cottonseed Treatment Evaluations in Arizona, 1989
- Evaluation of Cotton for Resistance to Pink Bollworm
- Insecticide Efficacy on Beet Armyworm Infestations in Open and Closed Cotton Flowers and Effects of Flower Infestation on Boll Abcission
- Gossyplure-baited Pink Bollworm Male Moth Trap Studies
- Sweetpotato Whitefly Populations in Cotton Genotypes at Poston, Arizona in 1988
- Early-season Cotton Square Removal with Ethephon and Initiation of Pink Bollworm Infestations
- The Influence of ULV Malathion, Applied for Boll Weevil Control, on Other Pest and Beneficial Species in Arizona Cotton Fields
- Planting Date and Susceptibility to Pink Bollworm
- Effect of Date of Planting and Irrigation Termination on Pink Bollworm Populations in Pima and Upland Cotton
- Nitrogen Management in Irrigated Cotton
- Sewage Sludge Effects on Soil Properties, Nitrogen Availability, and Yield at Marana, 1989
- Upland and Pima Cotton Response to Banded Phosphate Fertilization
- A Comparison of Three Cotton Tillage Systems
- Effect of NaCl on the Growth of Germinating Upland Cotton (Gossypium hirsutum L.) Seeds
- Accumulation of Proline in Germinating Cotton (Gossypium hisutum L.) Seeds During NaCl Stress
- Exogenous L- and D-Proline Does Not Reduce NaCl Inhibition of Radidle Growth of Germinating Cotton (Gossypium hirsutum L.) Seeds
Exogenous L- and D-Proline Does Not Reduce NaCl Inhibition of Radidle Growth of Germinating Cotton (Gossypium hirsutum L.) SeedsThe adaptive significance of proline (Pm) accumulation in cotton seeds can be assessed by determining if NaCl tolerance is influenced by changes in the Pm level of the seed. The objective of this study was to determine if exogenous L-Pro and D-Pro reduce NaCl inhibition of radicle growth of germinating cotton seeds. Seeds were imbibed for 24 h at 32°C before transfer to agar medium containing either Pro, NaCl or mixtures of both. Results indicate that exogenous Pro increases the Pro contents of cotton seed radicles and cotyledons to a similar extent. Such increases are independent of whether L- or D-Pro is fed exogenously. Results also show that exogenous Pro does not significantly reduce NaCl inhibition of radicle growth in germinating cotton seeds. .
Accumulation of Proline in Germinating Cotton (Gossypium hisutum L.) Seeds During NaCl StressThe accumulation of proline (Pro) in plants during NaCl stress may have adaptive significance and the study of this response could reveal a genetic strategy for enhancing NaCl tolerance. Our objective was to determine if the Pro content of germinating cotton seeds is altered by exposure to exogenous NaCl. Seeds were imbibed for 24 h at 32°C before transfer to agar media containing NaCl. After 24 h of NaCl exposure, the Pro contents of radicles and cotyledons were measured using a colorimetric assay. Results showed that Pro contents of both radicles and cotyledons increased as the level of NaCl increased. The bulk of Pro content increases were restricted to the radicle and occurred in the range of NaC1 concentrations from 200 to 400 mM NaCl.
Effect of NaCl on the Growth of Germinating Upland Cotton (Gossypium hirsutum L.) SeedsResponses to environmental stresses such as excess salinity are difficult to understand if not studied under defined conditions. The objective of this study was to determine if cottonseed radicle and cotyledon growth during germination was affected by exogenous NaCl. Cottonseeds were imbibed in moistened paper toweling for 24 h at 32°C before transfer to an agar media containing selected concentrations of NaCl for an additional 24 h. Radicle linear growth extension was stimulated at low NaC1 concentrations (80 mM), but increasingly inhibited as NaCl concentrations increased from 160 to 400 mM. Radicle and cotyledon fresh weights were increasingly inhibited by NaCl concentrations between 0 and 400 mM. NaCl inhibition of radicle fresh weights was more pronounced than that of cotyledons. We conclude that the inhibitory effects of NaCl can be quantified as reductions in cottonseed radicle and cotyledon growth.
A Comparison of Three Cotton Tillage SystemsTwo alternative tillage systems used significantly less energy than conventional tillage. The Sundance system used the least energy, averaging 35 horsepower-hours per acre (Hp-hr /ac), the Uprooter Shredder-Mulcher (USM) was intermediate at 50 Hp-hr /ac, and the conventional system used the most energy at 69 Hp-hr /ac. These energy savings translated directly into cost savings of about the same proportions. The USM and Sundance systems can plow down and prepare the next seedbed in about one-half the time that conventional tillage requires. In the two years of testing we could not measure any significant differences in cotton yield. So far, we have not found any significant differences in soil compaction.
Upland and Pima Cotton Response to Banded Phophate FertilizationFour field experiments were established in Arizona in 1988 and six in 1989 to evaluate the effects of banded phosphorus (P) fertilizer on cotton. Experiments each year involved both Upland (Gossvpium hirsutum L.) and American Pima (Q. barbadense L.). Banded applications of P fertilizer were made with placement of the concentrated band of fertilizer 6 in. below and 3 in. to the side of the zone of seed placement. Fertilizer sources of P₂O₅ were with 10-34-0 or 16-20-0. At all locations, a series of rates of applied P₂O₅ were established as the treatment variables, including a check (0 lb P₂O₅/acre). Rates of applied P ranged from 0 to 90 lb P₂O₅/acre, at increments of approximately 30 lb. P₂O₅/acre. In all cases, treatments in the field were arranged in a randomized complete block design with four replications. Plant measurements for plant height, flower numbers per unit area, number of mainstem nodes, and nodes to the first fndting branch were initiated by the fifth true leaf stage to evaluate plant response in terms of growth and development. Plant tissue samples were also taken at several stages of growth from each experiment throughout the growing season. Tissue samples consisted of petioles and leaf blades from the uppermost fully developed leaves. Petioles were analyzed for extractable PO₄-P and leaf blades for total P. Lint yield measurements also were taken. With the exception of one of the experimental locations in each year, no statistically significant differences (P≤0.05) were found among any treatments for any of the plant growth parameters. The same was true with regard to petiole PO₄-P and leaf blade total P levels measured. No significant differences among treatments were found for either Upland or Pima cotton with regard to lint yield in 1988 or 1989.
Nitrogen Management in Irrigated CottonTwo field experiments were conducted in 1989 in Arizona to compare several methods of nitrogen (N) management in Upland and Pima cotton. Standard preplant, preplant plus sidedress, and use of soil and petiole analysis for NO₃⁻-N were the basic methods of N fertilization management compared. A nonfertilized check treatment also was included with the N management treatments, which were arranged in a randomized complete block design in each experiment. Preseason soil samples and a series of in- season petiole samples were taken for all treatments and analyzed for NO₃⁻-N. The concentrations of NO₃⁻-N in the petioles reflected the boll load obtained and the crop fruiting patterns as well as the N fertilization patterns in the respective treatments. Final lint yield analysis revealed distinct differences among the treatments imposed at the Maricopa location but no statistically significant differences at the Safford location.
Effect of Date of Planting and Irrigation Termination on Pink Bollworm Populations in Pima and Upland CottonField experiments conducted in 1989 comparing effects of planting date and irrigation termination date on pink bollworm in both in- season and overwintering infestations indicated different responses depending upon the location and type of cotton. Tests were located at: Yuma Agricultural Center; Marana Agricultural Center; and Maricopa Agricultural Center. Infestations at Yuma ranged from 0% at early flowering to 80% infested bolls prior to harvest. Marana had equally high infestations at the end of the season, while Maricopa had the lowest infestations ranging from 2% to 5% for Pima and 3 %-17% for Upland. Planting date or species of cotton did not affect early infestation. Data comparing plots for overwintering infestations are still being evaluated. Continuous insecticide treatments were made at all locations after squaring began.
Planting Date and Susceptibility to Pink BollwormThe susceptibility of cotton to spring emergence of pink bollworm (PBW) was evaluated for a variety of planting dates in Pinal Maricopa, LaPaz and Yuma counties using historical climate records and heat-unit-based models that predict PBW emergence and cotton development. Early planted cotton proved most susceptible to the PBW emergence, however, cotton type (shoe vs. long staple) and springtime weather conditions both played an important role in overall susceptibility.
Early-season Cotton Square Removal with Ethephon and Initiation of Pink Bollworm InfestationsEthephon applied at rates of 0.50 or 0.75 lb AI/acre removed early-season squares and delayed initiation of pink bollworm, Pectinophora gossvpiella (Saunders) infestations and reduced the number of infested bolls on early-season fruiting branches, without affecting yield except for ethephon at 0.751b AI /acre at one location. Higher rates of application reduced yields. In most cases, ethephon treatments delayed flowering but plants compensated for removal of early- season squares and equalled or surpassed accumulated flowering of untreated control plants later in the season.
Sweetpotato Whitefly Populations in Cotton Genotypes at Poston, Arizona in 1988Studies were conducted to identify potential sources of cotton germ plasm resistant to sweetpotato whitefly (SPW), Bemisia tabaci (Gennadius). Numbers of adult SPW sampled using black pan and vacuum methods showed reduced numbers of SPW on GC-EXP-7007 experimental variety vs. all other entries. However, numbers of SPW pupae on leaf samples in most cases were not different. Pima P-62 had the high numbers of SPW adults per blackpan sample, and highest number of pupae/leaf sample.
Gossyplure-baited Pink Bollworm Male Moth Trap StudiesGossyplure, the pink bollworm, Pectinophora gossvpiella (Saunders), sex pheromone is an excellent tool as a bait in traps for detection, survey, research and monitoring male moth populations. We studied the within - and between-seasonal changes of pink bollworm male moth catches in gossyplure-baited live traps installed in cotton fields each year from 1981 to 1988. Seasonal average number of male moths caught varied from 14/trap/night in 1982 to 148 /trap /night in 1981. Male moths caught/trap/night were highly correlated with the minimum air temperatures. The number of male moths caught from March to June were significantly correlated with those caught from July to August, indicating that early spring trapping can be used to identify potential problem fields.
Insecticide Efficacy on Beet Armyworm Infestations in Open and Closed Cotton Flowers and Effects of Flower Infestation on Boll AbcissionIn 1988 severe beet armywonn (BAW) infestations resulted in damaged cotton flowers and foliage. Some insecticide applications failed to eliminate larvae in the flowers because applications were applied before the flowers opened. Applications made after flowers were open were more effective. In 1989, tests were conducted to define further these results. Karate™ applied when cotton flowers were open achieved 90% control compared to 9% when flowers were closed in one test, and 97% compared to 13 %, respectively, in a second test (P\0.01). A higher percentage (18 %) of cotton bolls was shed on day 7 following flower infestations than were shed (6 %) when flowers were not infested.
Evaluation of Cotton for Resistance to Pink BollwormCotton cultivars and germ plasm lines were screened for resistance to pink bollworm. Sixteen advanced strains were selected for resistance to pink bollworm and/or high yield potential. In a regional early maturing germ plasm lines test, only the short- season check had less seed damage caused by pink bollworm than did the long-season check. Five lines yielded more lint than both checks. In a Pima test, Pima S-6 nectariless had 14% less seed damage than Pima S-6. Seven pink-bollworm-resistant germ plasm lines will be released in the near future.
Suppresion of Inflection of Cotton Seedlings by Rhizoetonia Solani in the Presence of Thielaviopsis Basicola, the Causal Agent of Black Root RotHigh population levels of Rhizoctonia solani in a field in Coolidge, AZ which also contained Thielaviopsis basicola failed to cause the expected infection by R. solani in untreated seeds of Gossypium hirsutum. Growth chamber experiments with autoclaved soil amended with inoculum of both R. solani, and T. basicola had a significantly lower infection rate by R. solani than did the control soil with R. solani alone.
The Effect on Yield of Cotton Due to Incidence and Severity of Black Root Rot Caused by Thielaviopsis BasicolaIncidence of Black Root Rot of cotton and soil inoculum potential of the causal agent Thielaviopsis basicola were monitored throughout the season in two adjacent fields planted in mid April, 1987 in Duncan, Arizona. Mean inoculum potential in Field 1 soil was 65 cfu/g and 20 % of the seedlings were infected. In Field 2 the inoculum potential and percentage of infected plants were 225 cfu/g and 93, respectively. No cortical decay was noted after June 6 in either field. Yields were similar in both fields.
Effect of Harvest Date on Aflatoxin Contamination in the Yuma ValleyExperiments were performed at the Yuma Valley Agricultural Center to determine how timely harvest of cotton may affect aflatoxin contamination of cottonseed As the cotton was held in the field between the final irrigation and harvest, the quantity of aflataxin in the crop increased. Significant reductions in aflatoxin contents of seed were realized by harvesting in early September.
Response of Texas Root Rot to a Soil Sterilant the Second Year After Application in Marana, 1989Two years after sterilizing a sandy loam soil in Marana, we measured significant yield responses of short staple cotton. The yield response was significant in the first year as well, but was not enough to pay the cost of sterilization. This second year of yield response made the treatment economically feasible.