Evolution of sugar beet harvesters‘quality over the last decades, with special consideration of the methodical aspects of the test procedure

Abstract

The publication comprises a description of a test method for sugar beet harvesting devices and presents the field test results from 1984 to 2012. Quality parameters examined for harvesters were beet mass losses (both surface and sub-surface), root breakage, soil tare, and topping quality (accuracy and crown retention). The tests were held at Seligenstadt Estate near Würzburg/Germany on a test plot with loess soil. The introduction together with the chapter methods focuses on the test method which is constituted as an international standard of the International Institute of Sugar Beet Research (IIRB) dedicated to unifying the assessment of the working quality of harvest machines. The results from the last test held in 2012 are introduced in more detail outlining the working quality of the participating harvesters representing the state of technique. As a review targeted to reveal the trend of the last decades the test results from the beginning in 1984 are presented with a preceding paragraph on the progress and changes in the design and functions of the harvest machines in this time range.

The test results outline a shift in the topping quality tending to a slighter topping of the beets to avoid mass losses due to excessive overtopping. The share of beets that are over-topped decreased in the last tests. Major mass losses over the entire time span originate from breakage of the root tips accounting for 2.7%, on the surface, and underground mass losses amount to 0.9%. Soil tare strongly depends on soil conditions (soil water content and soil type) having an average of 9.8% over test years.