Sugarbeets are a unique crop which is unparalleled in its ability to produce and store sucrose. The sugarbeet root is a highly specialized plant organ for carbohydrate storage. Typical sucrose accumulation is generally between 16-20% with 20-23% being attainable. Research is continually being conducted to determine how to attain the highest amount of sucrose in the beetroot and sucrose per acre at harvest time. Yet sucrose content can vary significantly between harvest years. Studies have concluded a multitude of factors that affect sucrose accumulation that is both controllable and uncontrollable.
Factors that Affect Sucrose Accumulation
Sugarbeet genetics play an essential role in sucrose accumulation. There are significant differences between varieties and quantity of sugar produced. Choosing varieties that have been shown to have high sugar content consistently and root yield are essential to maximize sugar per acre. However, one must be careful in variety selection for other reasons. Often varieties with the least disease resistance have the highest sugar content. As breeders breed in genetic disease resistance, it can lessen the plant’s ability to produce sugar. These varieties must be placed selectively in fields without those disease issues. As genetics and techniques improve, plant breeders are doing a better job in overcoming the sugar drag.
Another factor that affects sucrose accumulation is the plant’s ability to capture solar radiation. The quantity of solar radiation available for photosynthesis depends on the amount of sunlight available and the ability of leaves to intercept it. Because of the earth’s tilt and rotation, day length, and radiation intensity changes. The highest available solar radiation occurs between May and July. This is when beets are small, and foliage cover of beets is the least. Foliage cover is the greatest August thru October when solar radiation levels are declining. Weather patterns during the summer that include cloud cover also will reduce sunlight.
The goal is to have rows canopied by June 20th the longest day of the year. Early planting, rapid emergence, and growth are essential. Narrow rows and optimum plants populations are also very important for increasing light interception. Xbeet® seed processing by Germains Technology has been shown to improved speed of emergence between 3-7 days and increase early growth. More on this topic next month.
Article by Sales Agronomist, Steve Poindexter