SEGREGATION AND RECOMBINATION OF CHEMICAL CONSTITUENTS IN A HYBRID SWARM OF BAPTISIA LAEVICAULIS × B. VIRIDIS AND THEIR TAXONOMIC IMPLICATIONS

Abstract

T urner , B. L. (U. Texas, Austin), and R alph A lston . Segregation and recombination of chemical constituents in a hybrid swarm of Baptisia laevicaulis × B. viridis and their taxonomic implications. Amer. Jour. Bot. 46(9): 678–686. lllus. 1959.—Selected plants from a hybrid population of Baptisia laevicaulis × B. viridis and individuals from “pure” populations of the parental species were examined chromatographically. The resulting patterns were then compared with the respective phenotypes by the use of hybrid indices. Although the parental type individuals yielded nearly uniform patterns, hybrid‐type plants showed a striking recombination of chemical components and there was an excellent correlation between chromatographic patterns and hybrid expression. Of particular interest was the detection of a new and distinctive compound in 2 of the hybrid‐type plants which was not observed in either parent. Chromatograms of 3 other Baptisia species also showed distinctive patterns, and their relationship to each other, as indicated by morphological features, was accompanied by similarities in the biochemical pattern. The segregation and recombination of biochemical constituents are discussed with respect to their evolutionary and taxonomic implications. It is suggested that an extension of the techniques utilized might provide for the establishment of “biochemical profiles” which should prove of considerable value to the systematist.