ON THE ROAD TO PRECISION AGRICULTURE

January, 2000

ON THE ROAD TO PRECISION AGRICULTURE

Michigan Precision Agriculture Research – NCR-180 is a committee of researchers from land grant university experiment stations who are working in precision agriculture. Committee members prepare annual research summaries, which are presented and discussed at a meeting in January. Below are abstracts of Michigan research presented to the group in January. Research reports for Michigan and other states can be found at: http://precision.agri.umn.edu/ncr180_Pawg/research/research.html

Mapping of Soil and Field Characteristics to Understand Soybean Yield - F.J. Pierce, Co-PI with W.J. Weibold, U of MO (PI) and scientists from IL, MO, IA, and SD

This is a 3-year project, funded by the North Central Soybean Research Program, to evaluate sensor-based measurements and develop procedures for mapping inherent and management-induced soil and field characteristics of importance to soybean and corn production in the North Central. Michigan has selected two fields for study, one on the fine textured Capac soil on the MSU and the other on a coarse textured Kalamazoo loam near Kalamazoo, MI. The MSU field was previously managed in small plot experiments for over 25 years which should contain considerable variation in management-induced soil variability. In 1999, intensive data on soils, terrain variables, and soybean growth and development were obtained. Soybean yield in 1999 varied from 38 to 73 bu/acre^-1. Spatial patterns present in remote sensed imagery obtained early in the growing season corresponded to spatial patterns in yields while imagery obtained mid-season indicated little spatial variation in soybean at that time. Plant height correlated well with final yields and remote sensed imagery. The Kalamazoo field has yield maps available since 1996. The field in 1999 consisted of 70 acres of soybean and 55 acres of corn and these are rotated annually. A drought occurred in 1999 at this site with very little rainfall in July - September so yield variability relates to soil water availability.

Remote imagery was obtained at critical times during the 1999 growing season and distinct areas of drought were clearly delineated within the field. Additional data layers on soils and terrain attributes will be obtained in 2000 and plant growth and development monitored at sites corresponding to the range of spatial variability observed to date.

Site-specific Management of Soybean Cyst Nematode, Scn - (Heterodera Glycines) -Haddish Melakeberhan, Felicitas Avendano, F. J. Pierce, and Oliver Schabenberger.

The overall research goal is to understand the spatial variability of SCN and its conduciveness to site-specific management approaches for SCN suppression. This research will quantify the spatial variability of SCN within fields, assess which SCN biological races control infestation intensity, investigate the temporal dynamics of SCN-plant nutrient interactions over multiple generations, and determine how SCN population dynamics relate to soil and landscape properties. In 1999, field studies assessing the spatial distribution of SCN over the growing season were conducted in two Michigan fields where SCN infection was known to occur. A geostatistical sampling design was imposed on each site and SCN counts obtained four times during the growing season. Soil fertility was measured on each soil sampling site and the field yield mapped at harvest. Based on results from 1999, additional space-time monitoring of SCN will be done in 2000 along with some initial testing of site-specific SCN management practices.

Roger Brook