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Advanced - Breeding Strategies

What is recurrent selection?

Recurrent selection refers to selecting for certain traits generation after generation.

With the interbreeding of reselected plants, the breeder can access favorable recombinations as well as stabilize traits within the genepool. Select your ideotype in each IBL, but don't be totally reliant on the phenotype because its not always indicative of the actual genotype. Make yield and quality trials with test crosses and select the best ten lines. Intercross and repeat.

After recurrent selection is done, select new individuals to be the new parents of IBLs. These are then recurrently selected for four or five generations. After recurrent selection has been done in two seperate programs, an F1 single cross of the two lines (A X B) is then produced.

In reciprocal recurrent selection (RRS), pollen of multiple A males is used to pollinate ideal B females and pollen of B used to pollinate ideal plants of A. Thus A is used as a tester to select for the combining ability of B plants, and B is a tester for A. At the same time,inbred seedlots(A X A) and (B X B) are made,using mixed male pollen and the best females of each population. Store the resulting seed-- the seedlines with the best combining ability will be used as parents of the next RRS cycle.

The (A X B) hybrid progeny are simply used as visual indicators of the combining ability that lies in the saved seeds.These specific inbred parental lines are kept in reserve until the progeny testing of the different (A X B) hybrids has shown which has better SCA and will make the better hybrids. Since this is such a complicated strategy, good note taking and organization are definitely required.