A CHARACTERIZATION OF SORGHUM (SORGHUM BICOLOR (L.) MOENCH) FOR BIOMASS UTILIZATION (PLANT BREEDING, GENETICS, ENERGY RESOURCES)

Increased utilization of novel biomass sources for energy conversion schemes has become a significant portion of energy related research and sorghum (Sorghum bicolor (L.) Moench) is often considered a viable potential resource. Plant breeding efforts to improve sorghum are limited in part by a poor definition of quality traits and their inheritance.; To address these concerns, six diverse sorghums were compared and then combined to produce a full F(,1) diallel with reciprocal crosses for genetic analysis. Fourteen agronomic, composition or quality traits were measured using chemical, biological and microscopic techniques. The six parental genotypes were grown at College Station and Weslaco, Texas in 1982 and 1983 while the diallel was grown at College Station in 1983. Data were analyzed using analysis of variance, correlation and the Jinks-Hayman methods of diallel analysis.; A significant genotype x environment interaction occurred for Brix % and yield per plant, but height and maturity did not display a significant effect. Among the traits evaluated, Brix % and total sugars were highly positively correlated and total sugars and cell wall % were highly negatively correlated. Structural components, lignin, cellulose and hemicellulose comprised between 50 to 65% of the total carbohydrate and as such indicate that utilization schemes must use these fractions. IVDMD was not highly correlated with any of the traits evaluated nor did the microscope measurements correlate in a useful manner.; Through the diallel analysis, it was determined that additive genetic variance was a significant factor for total sugars, cell wall %, IVDMD, hemicellulose and starch. However, partial dominance was indicated for several traits as well. Reciprocal effects were not a major factor for the traits evaluated. Heritability estimates ranged from a high of 88% for starch to almost zero for lignin; with total sugars, IVDMD and starch being the only traits with heritabilities greater than 35%. The results together indicate that a breeding program should continue to develop improved male and female lines for use in hybrids.