Non-Lethality of the Mid Factor in Lythrum Salicaria

Abstract

IN 1927 East¹ proposed a theory of the inheritance of style-length in tristylic Lythrum Salicaria which involved three factors. One of these, S, was epistatic to the others, and determined Short style as opposed to Mid and Long. The other two, each of which was supposed to give Mid style as opposed to Long, were lethal when homozygous and were linked. In 1932 East² seemed to abandon this theory in favour of a single non-lethal factor, having found for the first time a plant which, crossed with Long style, gave a large progeny nearly all Mid. In 1936, however, he explained³ that the 1927 theory was not abandoned, but applicable in his opinion only to the special type of plant with which first Barlow and later he himself had worked.