Diallel Analysis for Tocopherol Contents in Seeds of Rapeseed

• Published in: Crop science Vol. 41; no. 4; pp. 1072 - 1079
• Main Authors: Goffman, Fernando D., Becker, Heiko C.
• Format: Journal Article
• Language: English
• Published: Madison Crop Science Society of America 01-07-2001; American Society of Agronomy
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Flowers & plants; Fundamental and applied biological sciences. Psychology; Genetics; Genetics and breeding of economic plants; Lipids; Oils & fats; Plant breeding; Plant reproduction; Rapeseed; Seeds; Varietal selection. Specialized plant breeding, plant breeding aims; Vitamin E; Yield, quality, earliness, varia; Seeds; Production quality; Diallel analysis; Vegetable oil; Antioxidant; Genetic determinism; Cruciferae; Dicotyledones; Angiospermae; Genetic improvement; Brassica napus; Spermatophyta; Chemical composition; Heritability; Tocopherol; Oil plant (vegetal)
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2001.4141072x

Because of their nutritional and antioxidative properties, tocopherol production is an interesting trait for the lipid quality of oil crops. Total tocopherol content in rapeseed (Brassica napus L.) is medium to low, and therefore, higher levels of tocopherol are desirable in this species. The objective of the present study was to determine the inheritance of α‐, γ‐, and total tocopherol content and the α‐/γ‐tocopherol ratio in seed of rapeseed. Two diallel mating designs with six parents each were used. In Diallel I, the parents selected were high or low for total tocopherol content and in Diallel II, the parents were high or low for the α‐/γ‐tocopherol ratio. Parents and F1 hybrids were tested in a screenhouse in 1998 and under field conditions in 1999 by means of a completely randomized design with two replications. In addition, 10 selected F2 populations were grown along with their respective parents. Compared with the parents, the F1 hybrids showed a significantly higher γ‐tocopherol content of about 6 mg kg−1 seed for Diallel I and 24 mg kg−1 seed for Diallel II. General combining ability effects in both diallels were highly significant (P < 0.01) and much larger than specific combining ability effects for all traits studied. Reciprocal effects were not statistically significant. γ‐Tocopherol was not correlated with α‐tocopherol. The results indicate that tocopherol content and composition inheritances are strongly associated with additive gene action in rapeseed.