Meiotic behavior as a selection tool in silage corn breeding.

Area of Science:

• Plant breeding and genetics
• Agronomy
• Cytology

Background:

• Commercial maize hybrids are vital sources for inbred lines in breeding programs.
• Meiotic stability is essential for viable gametes, impacting maize production and hybrid development.
• Developing regionally adapted silage corn hybrids requires inbred lines with high meiotic stability.

Purpose of the Study:

• To evaluate the meiotic stability of five commercial silage corn hybrids used in southern Brazil.
• To identify hybrids suitable for retaining in breeding programs to derive inbred lines for new hybrid creation.

Main Methods:

• Evaluation of meiotic stability in five commercial silage corn hybrids.
• Utilized conventional squashing methods for cytological analysis.
• Quantified meiotic abnormalities including chromosome segregation, cytokinesis, cytomixis, and spindle orientation.

Main Results:

• All evaluated silage corn hybrids exhibited meiotic abnormalities.
• SG6010 showed the lowest mean frequency of abnormal cells (21.27%), while P30K64 had the highest (44.43%).
• Frequencies of abnormal meiotic products varied, with CD304 (7.63%) and Garra (43.86%) showing the lowest and highest, respectively.

Conclusions:

• Meiotic abnormalities are present in commercial silage corn hybrids.
• Hybrids CD304, P30K64, SG6010, and P30F53 demonstrated sufficient meiotic stability.
• These recommended hybrids are suitable for retaining in breeding programs to develop inbred lines for new hybrid production.