Genetic analysis of mesocotyl length and its relationship with other agronomic characters in rice (Oryza sativa L.)

• Published in: Euphytica 1993, Vol.72 (3), p.189-195
• Main Authors: MGONJA, M. A, LADEINDE, T. A. O, AKEN'OVA, M. E
• Format: Article
• Language: English
• Subjects: Adaptation to environment and cultivation conditions; Agronomy. Soil science and plant productions; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Oryza sativa; Varietal selection. Specialized plant breeding, plant breeding aims
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/BF00034157

Mesocotyl length is an important character in promoting seedling emergence of direct-seeded rice. Genetic analysis of rice mesocotyl length was conducted using a six parent diallel cross. Generation mean analysis was carried out on parents (P), F1, F2 and backcrosses (B) of three crosses to complement the genetic information from the diallel analysis. Both analyses demonstrated the presence of significant additive and dominance effects. Duplicate type of non-allelic interaction was detected by the generation mean analysis and two crosses showed significant negative dominance gene effect. Dominance was partial and the narrow sense heritability estimate for mesocotyl length was high, indicating the preponderance of the additive effects. Mesocotyl length was negatively but weakly correlated with the coleoptile length and length of the second internode L2. There was no correlation between mesocotyl length and other mature plant characters such as plant height and internode lengths L sub(1), (L sub(1) being the peduncle with subsequent internodes to the base of the plant). Selection for mesocotyl length can therefore be carried out independent of these plant characters and semidwarf rice varieties with long mesocotyl can be developed.