Crearea şi utilizarea analogilor androsterili şi restauratori de fertilitate a polenului la porumbul timpuriu

Abstract

The paper presents a generalization of the results of multiannual investigations concerning the reaction of early maize lines to M-type and C-type cytoplasmic male sterility (cms) and the development of male sterile analogues and pollen fertility restorers. 308 inbred lines belonging to the main groups of germplasm useful for early maize breeding were studied. The classification of the lines by their reaction to male sterility was preponderantly performed at the stage of combining ability evaluation in systemic crosses with male sterile testers. A high percentage of inbred lines (85,7%) maintaining M-type cms was established, while for C-type cms there was an approximately equal proportion of sterility maintainers (41,2%) and pollen fertility restorers (44.5%). The germplasm groups Euroflint, Early Batler, Northwester Dent and subgroups A654, CG-12 manifested similar reaction in both types of cytoplasmic male sterility. In specific cases deviations of male sterility expression were observed in relation to the genetic background. 9 male sterile analogues and 4 pollen fertility restorers were created as parental components for 14 registered maize hybrids.

Keywords

• maize
• zea mays
• hybrids
• inbred lines
• male sterility
• pollen fertility restorers
• backcrosses