1. Dep. of Plant and Soil Science Texas Tech Univ. Lubbock TX
2. Texas A & M AgriLife Research‐Corpus Christi TX
3. Dep. of Electrical and Computer Engineering Texas Tech Univ. Lubbock TX
4. Texas A&M AgriLife Research‐Lubbock TX
5. Dep. of Mathematics and Statistics Texas Tech Univ. Lubbock TX