I am planning to start breeding a strain that is short with a mild aroma, a high yield, and most importantly, is highly disease resistant.
To develop this strain I’ll need to inbreed. However, this lowers the immune system and vigor. I don’t want that to happen. To counter this tendency do I have to develop two separate lines that will be crossed eventually?

Hastings, Nebraska

As plants are inbred ? that is, crossed to themselves or close relatives ? the genes of the progeny become more homogeneous. This means that each pair of genes is more likely to be uniform or have the same alleles. Homogeneous plants have less vigor than plants that are heterogeneous and have different alleles. The result is the phenomenon known as hybrid vigor. When two different varieties are crossed, the progeny has more vigor than either parent.

To restore vigor to inbred lines, breeders develop two lines with similar characteristics. Since each line has been inbred, the two lines’ genes will have different alleles. Then the two lines are crossed to produce seed for production. The progeny will have the vigor that has been lost due to the inbreeding.

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