I have worked for TAES since 1994. I started at the Texas Agricultural Experiment Station-Amarillo at the Bushland site working for Mark Lazar and Jerry Michels. The projects I worked on included a greenbug fecundity study and a wheat breeding project to develop a Pursuit resistant wheat variety. Later I transferred to the agronomy department where I worked for Steve Winter.

At this position, I worked on sugarbeet variety testing. We looked at nitrogen management and sugarbeet root aphid effects. Nitrogen has an important role in sugarbeet production especially in the heavy clay soils of the Texas Panhandle. Too much nitrogen late in the growing season will cause increased impurities in the root which interfere with sugar extraction at the factory. However, too little nitrogen will lead to yield losses that equal economic losses. Nitrogen requires a fine balance that is hard to manipulate in heavy clay soils. Our research was aimed at studying this nitrogen balance for sugarbeets.

In summer 1997, I worked on a soybean variety test. Soybeans are not commonly grown on the Texas High Plains, but under irrigated conditions soybeans can produce quiet well in the Texas Panhandle. Due to the increasing swine industry in this area, we felt the need to investigate soybean production in anticipation for a higher soybean demand.

Current Work:

         Research Associate with the Lubbock soil physics dept. since January, 1998.

Precision Agriculture is a big priority at our center. We are designing a nitrogen-balance study on cotton with a precision ag emphasis for the summer of 1998. This study will help us determine the scope of our sampling procedures, i.e. how frequently to sample, what density to take samples, grid size. The objective of this study will be follow N inputs and available N to the outputs throughout the season. Plant samples will be collected throughout the growing season and analyzed for total N. Soil samples will be evaluated to determine the amount of N that leaches through the soil and out of the rooting zone.  In another study, we are taking soils samples every 60 inches across a pivot irrigated field to determine the amount of variability in such a small area.

Education:

        Bachelor’s degree in Agronomy and Soils from Auburn University in June, 1992, .

Received Master’s degree in Plant Science from West Texas A&M University in August, 1997. Thesis title: Comparisons of chlorophyll meter and petiole length with standard petiole nitrate testing for determining nitrogen status of sugarbeet.

Abstract:

Sugarbeet (Beta vulgaris L.) requires careful nitrogen (N) management to balance root yield with sucrose content and purity. Excessive N late in the growing season greatly increases impurities, which interfere with the extraction and recovery of sucrose during processing. Currently petiole nitrate-N (NO3-N) testing is the standard method for monitoring N concentration of sugarbeet. The chlorophyll meter (SPAD-502 Chlorophyll Meter, Minolta Camera Co., Ltd., Japan) or petiole length may offer an alternative method for monitoring N needs of sugarbeet that will allow more timely correction of an early season deficiency.

This experiment was conducted at the Texas Agricultural Experiment Station Bush Research Farm on furrow irrigated Pullman clay loam near Bushland, Texas. Four rates of N replicated four times were applied in a Latin square design with three sugarbeet cultivars as subplots. Petiole NO3-N samples, chlorophyll meter readings, and petiole length measurements were taken on three dates, and results were evaluated to determine if a correlation with sugarbeet yield, sucrose, or quality exists.

Petiole NO3-N at the July 18 sampling date were the best estimators of sucrose and quality at harvest. A regression analysis using July 18 chlorophyll meter readings to estimate sucrose and molasses concentration reveals a limited ability to estimate sucrose (r2=0.55) and molasses (r2=0.53) on sugarbeet cultivar HMI 9155.

July 18 petiole lengths were better predictors of sucrose than the chlorophyll meter for HMI 9155 (r2=0.63) and 9355 (r2=0.64). The data from this experiment suggest petiole NO3-N still gives the best estimate of N status of sugarbeet. Results from the chlorophyll meter appear to be confounded by factors affecting the sugarbeet plant other than applied N.

Publications:

Booker, J. D. 1997. Comparisons of chlorophyll meter and petiole length with standard petiole nitrate testing for determining nitrogen status of sugarbeet. M.S. Thesis. West Texas A&M University.

Booker, J. D., S. Winter, and R. Van Meter. 1997. Progress in precision agriculture. Poster at the 1997 Amarillo Farm Show. December 2-4, 1997.

Lazar, M. D., G. J. Michels, and J. D. Booker. 1995. Reproductive and developmental rates of two greenbug biotypes in relation to two wheat host resistance genes. Southwestern Entomologist. 20: 467-482.

Michels, G. J., M. D. Lazar, D. A. Fritts, and J. D. Booker. Biotype E greenbug reproduction and development through multiple generations on resistant and susceptible winter whet genotypes. Southwestern Entomologist. 22: 431-437.

Winter, S., J. Booker, R. Van Meter, and S. Carter. 1996. 1995 Sugarbeet research results. AREC 96-1.

Winter, S., J. Booker, and R. Van Meter. 1997. Yield mapping for research and extension. AREC 97-25.