Recoverable Sucrose Yield Research Articles

Effects of Ploidy Level on the Components of Sucrose Yield and Quality in Sugarbeet1

Comparisons of 2χ, 3χ, and 4χ sugarbeet (Beta vulgaris L.) lines and hybrids were made to determine the effects of ploidy level on sucrose yield and quality components in equivalent and non‐equivalent hybrid populations.The relative order of importance for the components of recoverable sucrose was generally the same for all three ploidy levels, with root weight having the greatest path coefficient direct effect and juice purity the least.Purity generally decreased as .ploidy level increased; this decrease was accompanied by increase in the quantity of non‐sucrose chemical components in the extract.Significant differences were found between reciprocal equivalent 3χ hybrids for both yield and quality components. Recoverable sucrose yield of triploids produced from tetraploid female plants. [3χ(4χ ♀ )] averaged 17% greater than that of the reciprocal 3χ(4χ ♂ ) hybrids. The same 3X(4x ♀ ) triploid hybrids also were lower than their reciprocal equivalents in extract concentrations of Na. K, and total N, with decreases of 9, 17, and 12%, rcspectlvely. When components are expressed in rag/100 g sucrose, the corresponding decreases were 13, 20, and 16%, respectively.

Effect of N Fertilization on Sugarbeet Crown Tissue Production and Processing Quality1

AbstractOver the past 4 decades, sucrose content of sugarbeets (Beta vulgaris L.) has decreased while root yield has increased. Reasons reported include processing of more crown material, because mechanical harvesting removes less crown tissue than hand‐topping methods, and incre ased use of N fertilizer. Our objective was to determine the relationship between N application rate and sugarbeet crown tissue production, and its effects on processing quality of sugarbeets. Reported are the results of two studies conducted in 1975 and one in 1976, each using a different sugarbeet cultivar and seven N rates. Green petiole material was removed before each sugarbeet was sectioned into root and crown tissues for yield and quality analyses. Crown tissue increased linearly as rates of N application increased. Root tissue and recoverable sucrose yields were near maximum when spring soil NO3‐N or soil NO3‐N plus added N reached 200 to 225 kg/ha. At higher N levels, crown tissue yield increased and sucrose content in both root and crown tissues decreased, offsetting any potential benefits from increased whole beet yield. When N was adequate for maximmn sucrose production, crown tissue contributed approximately 20% of the total recoverable sucrose per ha. As N rate increased, sucrose concentration, extractable sucrose per metric ton, and purity decreased whereas Na, K, amino‐N, invert sugar, and imaturity index values increased for both root and crown tissues. Root tissue always had higher levels than crown tissue of extractable sucrose and purity and lower levels of Na, amino‐N, invert sugar, and impurity index. Crown tissue production can be minimized, and processing quality of sngarbeets can be improved by conservative use of N fertilizer.