Skip to main content
ARS Home » Southeast Area » Jonesboro, Arkansas » Delta Water Management Research » Research » Publications at this Location » Publication #307727
Title: Development of a solar radiation stress index for cotton

Author
item Reba, Michele
item TEAGUE, TINA - Arkansas State University

Submitted to: Arkansas Agricultural Experiment Station Research Series
Publication Type: Experiment Station
Publication Acceptance Date: 4/7/2014
Publication Date: 8/1/2014
Citation: Reba, M.L., Teague, T.G. 2014. Development of a solar radiation stress index for cotton. Arkansas Agricultural Experiment Station Research Series. 618:66-71.

Interpretive Summary: The incorporation of solar radiation measurements in understanding plant stress has the potential to help improve our understanding of yield variability in the cloudy, Mid-South cotton production region. In Mid-South cotton fields, a marked increase in small boll abscission following a progression of cloudy days may be erroneously attributed to effects of arthropod pests. A solar radiation stress metric was developed to quantify potential stress from cloudiness. The solar radiation stress metric was calculated by taking a ratio of measured incoming solar radiation to calculated clear-sky radiation for the location of interest. This could be applicable in interpreting yield and fiber quality results from regional variety trials to understand response to overcast conditions. Real-time weather station data also could be made available to producers and crop advisors, as well as researchers, alerting them to potential for reduced boll retention and maturity delay should the solar radiation deficit stress occur during the effective flowering period and during boll maturation.

Technical Abstract: In Mid-South cotton fields, a marked increase in small boll abscission following a progression of cloudy days may be erroneously attributed to effects of arthropod pests. Zhao and Oosterhuis (2000) found that 4 days of shading impacted yield especially during the period of effective flowering and boll maturation. A solar radiation stress metric was developed to quantify potential stress from cloudiness. We first quantified cloudiness on a daily time scale and then tracked if the cloudiness persisted for several days. Incoming solar radiation was measured in 2012 and 2013 at the Judd Hill Foundation Research Station, near Trumann, AR, with a LP02 Pyranometer (Campbell Scientific, www.campbellsci.com, Logan, UT), a full-spectrum solar radiometer. Hourly totals of incoming solar radiation were cumulated for each day to determine total incoming solar radiation in MJ m-2 day-1. Clear sky radiation is the maximum amount of incoming solar radiation for a given day at a specific location. It is calculated from daily extraterrestrial radiation. Daily extraterrestrial radiation was calculated from the solar constant, solar declination and time of year. Clear sky radiation was generated from extraterrestrial radiation corrected for elevation. The cloudiness for a given day was taken to be the ratio of measured incoming solar radiation to calculated-clear sky radiation, hereafter referred to as the cloudiness ratio. To track the persistence of cloudy conditions, a three-day running mean of the cloudiness ratio, centered on the third day, was the basis for the solar radiation stress index. The incorporation of solar radiation measurements has the potential to help improve our understanding of yield variability in the cloudy, Mid-South production region. This could be applicable in interpreting yield and fiber quality results from regional variety trials to understand response to overcast conditions.