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Hairy's Inheritance, Investigations into the inheritance of hairs on rapid cycling Brassica rapa, RBR
This powerpoint presentation contains copies from my research notebook and photos documenting some of my investigations into the inheritance of hairs on the leaves and stems of RBR. In this study, I have mass crossed a population of 25 very hairy,Hir(9), strongly purple, Pan(8), as the paternal parent,P2, with 25 hairless, Hir(1), completely green, anthocyaninless, anl, maternal parents. The cross is facilitated by the use of the male sterile gene, mst2, in the maternal population, in which approximately half of the plants are male sterile. Male fertile plants are recognizable before anthesis and are removed before the crosses are made. The cross, enables the production of F1 and F2 progeny suitable for data collection and analysis, selection, test crossing and further analysis. Patterns of segregation for the anl marker can be compared with the segregation for the quantatively inherited phenotype of hair numbers. Seed of the strongly purple, very hairy RBR parent, P2, were obtained from Neal Williams of Bryn Mawr College, PA, who obtained them from Bruce Fall, Biology Program, Univ. of Minnesota, St.Paul. http://www.fastplants.org/activities.variation.hairs.php#menu. Bruce's stock had undergone 14 cycles of selection for increased numbers of hairs on the first internode of the stem of RBR. I have increased the very hairy stock without selection for hairyness.