1. Texas Agricultural Experiment Station, Texas A&M University, 1102 East FM 1294, Lubbock, TX 79403, USA, and Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA.
2. Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843, USA.
3. Texas Agricultural Experiment Station, Texas A&M University, Stephenville, TX 76401, USA.
4. Tarleton State University, Stephenville, TX 76401, USA.
5. Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA.