Root tissue strength and storage losses of sugar beet varieties as affected by N application and irrigation

Abstract

There is some evidence that sugar beet root tissue strength affects damage susceptibility and storage losses. This study aimed at analyzing the effect of N application and of irrigation on tissue strength of sugar beet varieties, on root composition, and on root tip breakage and storage losses. For this purpose, field trials in six replicates with three sugar beet varieties were carried out with three N doses in The Netherlands and Belgium in 2018 and 2019, alternatively with three irrigation treatments in Sweden in 2018 and 2019. Results show a low impact of N application and irrigation on puncture resistance, tissue firmness and compressive strength of the roots, while varieties differed always stronger and significantly. Cell wall composition (pectin, hemicellulose, cellulose, lignin) did not differ markedly in roots from different environments (sites, years) and varieties, giving no explanation for differences in tissue strength. However, the percentage of cell wall material (AIR, marc) and of dry matter were higher in roots with higher tissue strength. Root tip breakage and sugar losses during storage tended to be lower when root compressive strength of varieties was higher. Hence, root tissue strength could serve as an indirect selection criterion for reduced damage susceptibility and improved storability of sugar beet varieties.