Question

Four inbred lines of wheat are crossed. The cross is called

• A. Double cross
• B. Multiple cross
• C. Dihybrid cross
• D. Tetrahybrid cross

Answer 1

The correct option is A Double cross

In double-cross hybrid, two stages of the crossing of two pairs of inbreds or four inbreed lines are involved. In Step 1, two pairs of inbreds are crossed to produce single-cross hybrids. In Step 2, the two single-cross hybrids produced in Step 1 are crossed to produce the double-cross. Double-cross hybrid is important in the production of organic corn, wheat where the herbicides are not used. Therefore, seed producers desire parents that have good vigor and can compare successfully against weeds.