Submitted to: University of Missouri Agricultural Experiment Station Publication
Publication Type: Experiment Station
Publication Acceptance Date: 8/15/2016
Publication Date: 9/2/2016
Citation: Vories, E.D. 2016. Precision agriculture approach for improving cotton irrigation. Fisher Delta Research Center Annual Field Day Report 2016, September 2, 2016, Portageville, Missouri. p. 26-27.
Technical Abstract: Cotton is a vital part of the southeast Missouri economy and while we’re not currently facing problems with groundwater decline, it’s still important to apply the right amount of irrigation at the proper time. We currently have several projects at the Fisher Delta Research Center with that aim. For surface irrigated fields, cotton producers commonly employ patterns such as every-other-furrow irrigation to allow them to irrigate fields in one set, saving time and labor. While many years there is sufficient rainfall that no obvious deleterious effect is observed, producers are always concerned that they are reducing yields with the strategy. We’re completing a multi-year study where we looked at the impact of four furrow irrigation patterns: every furrow; every other furrow (same furrows each time); every other furrow (alternating); and every third furrow; along with rainfed cotton. In addition to using a yield monitor to observe the spatial distribution of yield, we also employed tractor mounted sensors to measure the spatial distribution of canopy height, temperature, and reflectance. In addition to irrigation patterns, two new studies are focused on improving cotton irrigation recommendations and also deal with spatial distribution of crop parameters. For irrigation timing, the crop coefficient (Kc) is generally assumed to be a uniform function of age or growing degree days. However, proper use of site specific technologies including variable rate irrigation (VRI) will require a more detailed understanding of the spatial and temporal variability. Research has shown that canopy reflectance is one method for estimating Kc values in the field and we’re investigating the differences among the most commonly grown cultivars. Finally, we’re working with a team of ARS researchers at Bushland, TX, Stoneville, MS, and Florence, SC, to investigate the use of center pivot mounted sensors to automatically prepare prescriptions for VRI. This information will help to insure that we continue to provide cotton producers with state-of-the-art production recommendations and our farming practices are sustainable.