Two inheritance studies were conducted at College Station, Texas, to determine the nature and mode of inheritance of fermentablecarbohydrates in stems of Sorghum bicolor (L.) Moench. harvested stems were stripped and topped, and the juice extracted on a cane press mill. Carbohydrates yield was defined as the sum of the glucose, fructose, sucrose and starch concentration in the juice times the volume of juice extracted. In one study involving 16 F1 hybrids from 2 female and 8 male parents, general cambining ability (GCA) values were significant for carbohydrate yield, juice volume and each of the carbohydrate fractions. Specific combining ability (SCA) values were significant only for glucose, fructose and sucrose. The predominance of additive over non-additivegenetic variance was confirmed by a GCA/SCA ratio of 13.6 for carbohydrate yield. Correlation and regression analysis indicated that juice volume and sucrose were the most important components of carbohydrate yield. Glucose, fructose and starch contributed only slightly more to the statistical model for predicting carbohydrates yield. Although the average heterosis effect was small and negative, 7 of the hybrids yielded more stem carbohydrate than the better parent. In addition, an average positive heterosis was found for yield of fresh heads, suggesting that higher grain yields of hybrids would offset any loss of stem carbohydrate. Another study consisted of 5 parents and the 10 F1 hybrids of a one-way diallel cross. The aprents represented a range (...).