Effect of on-farm storage method on root mass and sugar losses of sugar beet

Document Type : Scientific - Research

Authors

1 Associate Professor of Sugar Beet Seed Institute (SBSI) - Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran.

2 Instructor of Sugar Beet Seed Institute (SBSI) - Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran.

3 Instructor of Sugar Beet Seed Institute (SBSI), Karaj, Iran

Abstract

The objective of the present experiment was to study the root mass and sugar losses of sugar beet during the storing beets in two methods of on-farm storage. A factorial split plot experiment with nine replications based on a completely randomized design was conducted during 2005 in the experimental fields of Sugar Beet Seed Institute (SBSI) of Iran, in Karaj. Combination of two harvest dates (early October and November) and two on-farm storage methods (small pile in the field as a check- farmer method- and recommended pile close to the field) were arranged in the main plots. Four root storage intervals of 2, 4, 6 and 8 weeks were arranged in the sub plots.  About 25 sugar beet roots were placed in a plastic net bag as an experimental unit.  Quality and quantity traits of beet samples were determined in all treatments using standard methods. Sugar losses and mass loss of beet samples were determined relative to each harvest date, before storing sugar beet roots.  The results showed that mass loss of sugar beet in the small pile was 2.6 times greater than that stored in the recommended pile method. Storing sugar beet in the small pile until eight weeks compared to storing beet in the recommended pile method resulted in an increase in sugar content by 2.48% (mostly due to 4.6% root dehydration). However, the concentration of sucrose on dry weight basis was reduced by 2.40%. Both sugar content and root dry matter content increased significantly by increasing the duration time of sugar beet storage until six weeks. During the two first weeks of storage, both root mass and sugar losses were significantly greater than that in the later weeks of storage. Sugar losses during the two first weeks were 40% more than that of the second two weeks of beet storage. The results of storage cost of sugar beet in the recommended pile was 50625 Rials per ton of sugar beet in terms of loading from field, transporting and keeping in the on-farm storage. However, sugar losses in this method were 1072 gt-1d-1, equivalent to 5896 Rials less than that in small pile in the field (farmer method).  In conclusion, if farmers have to keep the harvested beet roots in the field more than nine days (equal to 27 Respiration Degree Days, RDD), it is economic to store the beet roots according to the recommended on-farm storage.  From technical quality point of view, as the high quality of beet root as a row material may reduce the sugar losses of beet processing in the factory, the sugar factories are recommended to encourage the farmers to keep the harvested roots immediately in the recommended pile by paying some bonuses to the farmers.

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