Location: Cotton Production and Processing Research
Project Number: 3096-21410-009-010-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 15, 2021
End Date: Jul 14, 2023
The goal of this research is to develop universal recommendations on safe moisture levels and storage period lengths for seed cotton stored in round modules in order to minimize lint and seed quality losses during pre-ginning storage. Additionally, we aim to evaluate the accuracy of seed cotton moisture data collected by several “off-the-shelf” moisture sensing technologies relative to reference gravimetric moisture content measurements and demonstrate their utility in predicting post-storage changes in lint and seed quality.
Cotton grown in multiple areas will be harvested with cotton strippers and cotton pickers with round module forming capability to capture storage condition variation resulting from different growing environments and harvest methods. The crops will be produced and prepared for harvest using irrigated or dryland management practices typical for the area. Harvest will begin in the morning of each day when seed cotton moisture content is high from nighttime dew and relative humidity and progress continuously throughout the day as the crop dries from exposure to sunlight and wind. Harvest will continue into the evening hours as the seed cotton increases in moisture content due to rising relative humidity. The goal is to produce modules with varying levels of seed cotton moisture for observation over multiple pre-ginning storage periods. A harvester based system will be used to gather moisture content, diameter, and weight data on each module during harvest and the resulting moisture content data will be used to group the modules into four moisture groups: <9%, 9-12%, >12% morning, and >12% evening. It is hypothesized that morning and evening seed cotton moisture levels over 12% will produce different storage effects due to different seed and foreign matter moisture levels (wetter seed/foreign matter in the morning, drier in the evening). Approximately twelve round modules from each of the four moisture range groups will be sampled during formation on the harvester to collect samples for foreign matter content analysis and gravimetric moisture content analysis. The moisture content samples collected in the field will be sealed in moisture tight bags for shipment to an analytical testing laboratory. The fractionation samples will be stored in air-permeable sample bags for shipment to the laboratory for analysis. Additional, seed cotton moisture content measurements will be taken on each module using sensing systems employing the capacitance, resistance, time domain reflectometry, and through-transmission microwave technologies. After harvest, the round modules will be grouped according to target moisture range. At random, half of the modules in each moisture group will be assigned to ginning groups 1 and 2. Ginning group 1 will be transported to the commercial gin of the grower’s choice for ginning within one week of harvest. Group 2 modules will remain in the field for approximately 6 weeks before being transported to the gin for ginning. Ambient air conditions during harvest and storage will be monitored and logged. Prior to ginning, moisture content measurements of the seed cotton in each module will be conducted using the same measurement technologies used at harvest and compared to gravimetric moisture content measurements taken prior to ginning for accuracy. Additionally, ginned seed and lint samples will be collected for seed quality, and HVI/AFIS lint quality analyses. The change in measured response variables between ginning dates will be analyzed by target initial moisture content level and storage duration using the Mixed procedure in SAS.