Submitted to: American Society of Sugar Cane Technologists
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/14/1998
Publication Date: N/A
Interpretive Summary: Sugarcane and related grasses have been used in the basic breeding program to expand the genetic base of commercial sugarcane, transfer of desired characteristics, and explore the heterotic effect on yield and sugar content. Genetic information is needed so that desired characters can be effectively used in sugarcane breeding programs. Progeny produced by mating interspecific and intergeneric hybrids as females with commercial cultivars as males were used to estimate the fraction of the phenotypic variability transmitted from parents to offsprings. Both morphological (stalk: height, number, diameter and weight) and juice-quality (Brix, sucrose content and purity) characters were evaluated. Estimates of heritability varied considerably and were dependent on the methods of estimation and characters. Heritability of Brix and percent sucrose was consistently moderate, but heritability estimates for the other five characters varied. Information on heritability of morphological and juice-quality characters from backcross populations of interspecific and intergeneric sugarcane hybrids should assist in establishing more effective backcrossing and selection strategies for the germplasm utilization.
Technical Abstract: Saccharum spontaneum, Erianthus sp., and Miscanthus sp. have been used through interspecific and intergeneric hybridizations to transfer desired characters to cultivated sugarcane. BC2 progenies produced by mating four BC1 hybrids (one interspecific and three intergeneric) as females with three commercial cultivars as males were used to estimate heritability for both morphological (stalk: height, number, diameter and weight) and juice-quality (Brix, sucrose content and purity) characters. Female effects were significant for all characters, but only juice-quality characters showed significant male and male-female interaction effects. Additive genetic variance was greater and more important than non-additive genetic variance for most characters except stalk height and stalk number. The ratios of genetic to non-genetic variance showed there was some degree of overdominance for genes affecting both stalk height and stalk number, but there was little or no dominance for genes affecting either character. Estimates of heritability varied considerably and were dependent on the method of estimation and characters. Heritability of both Brix and sucrose content was consistently moderate, but heritability estimates for the other five characters varied.