Submitted to: Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2017
Publication Date: 11/4/2017
Citation: Mahan, J.R., Payton, P.R. 2017. An agrocentric analysis of regional rain patterns as they relate to a rained cotton cropping system on the Southern High Plains of Texas. Agriculture. 7(11). doi: 10.3390/agriculture7110093.
Interpretive Summary: Cotton is often produced without the aid of irrigation. Under such rainfed conditions, the amount and pattern of rain during the growing season is a major determiner of yield and quality. The relationship between rain in an environment and the management of a rainfed cotton crop is an important consideration for the optimization of production. In this study we have analyzed 10 years of rain and weather data to determine if there are certain planting dates that are generally preferable over others. We identified 7 possible planting dates for cotton in the Lubbock, TX area and analyzed rain patterns and crop water requirements for each planting date. Over the 10-year study period we produced 70 potential cotton crop seasons. Patterns indicate that early and late plantings may be advantageous and contribute to less water stress in the crop. Additional analyses will include crop models and pattern recognition to refine predictions. This analysis will provide information to rainfed cotton producers on the benefits and risks associated with various planting dates.
Technical Abstract: Rain is the major limiter of cotton yields for the semi-arid region of the Southern High Plains of Texas. The effects of rain are appropriately analyzed in terms of the effect of the rain on the crop and an “agro-centric rain” analysis seeks to understand the amounts and timing of rain events within a defined management system. In this study, the cotton growing season on the Southern High Plains of Texas at Lubbock, TX, was analyzed in terms of the crop water environment associated with 70 potential cotton crop seasons across the 10-year period from 2006 to 2015. For the 10-year period, the 238-day cotton growing season was divided into 7 potential cotton crop seasons of 154-days each. Rain and crop water status (as reference and crop evapotranspiration) were calculated for each of the 70 potential cotton crop seasons. The rain amounts showed a pattern of highest rain amounts associated with earlier plantings. Reference evapotranspiration showed a strong pattern with maximum values associated with the mid-season plantings and minimum values associated with the earliest and latest plantings. Crop stress, as the difference between rain and reference evapotranspiration, showed a pattern with maximum stress associated with the earliest planting dates. The results indicate that crop water status across potential cotton crop seasons can vary with planting date across years to an extent that it may be possible to exploit the variation to improve yield and or quality in terms of germplasm and management practices.