Browsing by Author "Dr. John Van Duyn, Committee Member"

Now showing 1 - 1 of 1

Influence of Plant Available Water on Yield Potential and Crop Water Stress Index in Corn.
(2005-11-17) Gurganus, Kent Rodgers II; Dr. Ronnie W. Heiniger, Committee Chair; Dr. Carl R. Crozier, Committee Member; Dr. John Van Duyn, Committee Member
Understanding and measuring the driving forces behind potential yield within the growing season are vitally important in corn production. The objectives of this study were to (i) quantify the effects of location, year, and water regime on the dynamic temporal changes in plant available water (PAW) over the growing season, (ii) determine if there was a relationship between plant available water per fifteen centimeters of soil depth (PAW15cm) measured at different dates throughout the growing season and corn yield, and (iii) quantify the relationship between plant available water measured at four depths throughout the growing season and crop water stress as determined by crop water stress index. Rainfall, water treatments, and location (related to differences in soil texture and how irrigation treatments were applied) were the main factors influencing the dynamic changes in PAW measured at different sampling depths in 2001 and 2002. Rainfall contributed heavily to changes in PAW at the shallow sampling depths making it difficult to use single measurements of PAW at these depths to determine yield potential. The influence of irrigation was observed at the deeper sampling depths due to the accumulation of water that was not affected by transpiration and evaporation. Significant correlations between PAW15cm and yield were measured. However, the lack of strength of these correlations made it difficult to use them to predict corn yield. Correlation of CWSI and PAW15cm at each measurement date and location indicated significant relationships. The variation in CWSI was accounted for by variation in PAW15cm at the lower sampling depths.