Management of centre pivotirrigation on Florida potato: Impact on plant physiology and yield components.
Byrd, S. A.. 2012. M.Sc. University of Florida
Abstract
Proper irrigation scheduling can lead to higher returns and more sustainable production practices. This is especially true for potato during the tuber bulking stage when the largest irrigation applications are needed to meet greater crop demand. In an attempt to reduce irrigation input with a minimal reduction in yield, we evaluated a novel deficit irrigation treatment utilizing mild water stress in a commercial potato production field in Florida with the FL-1867 cultivar. The irrigation treatments in this project consisted of: the normal irrigation schedule (FULL); and an irrigation skip, or a dry pass, followed by typical irrigation for two passes of the center pivot (PARTIAL). The partial irrigation treatments were designed to be initiated after primary tuber initiation was complete. To monitor the effect of the partial irrigation schedule on the crop, plant physiological measurements and soil and plant nutrient samples were taken throughout the growing season, and yield and quality measurements were quantified. Plant water use was determined through the use of sap flow sensors, and soil moisture was logged continuously during the season with the use of capacitance probes. In both years, the irrigation treatment had no effect on plant physiological processes, and
impact on certain plant and soil nutrients. The yield with the partial irrigation treatment was 25% lower than the yield of the full irrigation. This significant reduction in yield in 2011 was most likely due to the partial irrigation treatment occurring too early in the season, and led to a delay of the initiation of the partial irrigation treatment in 2012. This delayed resulted in no significant difference in yield in 2012. A relationship was found between total daily water use (as measured with sap flow) and soil moisture showing the efficacy of using soil moisture as a tool for efficient irrigation scheduling. This study shows the potential for a reduced irrigation schedule as a viable option for Florida potato growers and as a sustainable management option for potato production.
