In line x tester breeding, the selection of appropriate line and tester parents is crucial for the success of the program. For line parents, key criteria include genetic diversity, desirable agronomic traits, and good combining ability. Lines should represent a broad genetic base to maximize heterosis in crosses. Desirable traits such as yield potential, disease resistance, and quality characteristics are important. Good general combining ability (GCA) is preferred for lines to produce superior hybrids. For tester parents, the main features sought are good specific combining ability (SCA), ability to discriminate among lines, and representation of the target heterotic group. Testers should have a narrow genetic base and be genetically distant from the lines. They should effectively reveal the combining ability and breeding value of the lines when crossed. Practical considerations like seed production capacity and adaptability to target environments are also important for both lines and testers. The goal is to identify parent combinations that produce high-performing, stable hybrids suited to the breeding program's objectives.

In line × tester breeding, selecting appropriate line and tester parents is essential for developing superior hybrids. Line parents should exhibit genetic diversity, desirable traits (such as disease resistance and high yield), stability across environments, and strong combining ability (both general and specific). They should also be well-adapted to the target growing conditions. Tester parents should have a broad genetic background, a proven track record of producing high-yielding hybrids, and compatibility with the selected lines to facilitate successful crosses. Additionally, testers should express complementary traits to enhance overall hybrid performance and be effective in revealing the combining abilities of the lines. Considering phenotypic traits, molecular markers for genetic diversity, adaptability to stress conditions, and seed production potential will further strengthen the selection process, ultimately increasing the chances of developing successful hybrids.