Hybridization between hexaploid triticale and Triticum monococcum L. I. Progamic reaction

摘要

One triticale (AUAUBBRR) was crossed with 15 forms of Triticum monococcum (AbAb) from different geographical regions. Twenty-four hours after hand pollination, the ovules were removed from the florets and fixed and stained in a solution containing water-soluble aniline blue. By means of a fluorescent microscope, assessments were made for the amount of pollen on stigmatic surface, the value of pollen germination, and the length of pollen tubes, calculated in diameters of the corresponding pollen grain. An absolute progamic barrier was observed in none of the 15 initial combinations. Five to 20 percent of pollen grains germinated, with important differences between the pollinators. The latter was observed for pollen tube length, too. A contingency table analysis revealed a strong correlation between both traits. It was shown that quantitative differences of this kind can only be detected if the real data distribution is used. A transformation into vectors or ranks, was less informative. Furthermore, a correlation between the quantitative differences mentioned above and the number of fertilized ovules was visible. In case of pollen germination and pollen tube length, (–values were 0.69*and 0.71*, respectively. It can be concluded that there is some kind of “specific crossability” even in such complicated distant hybridization. It is necessary, therefore, to involve more than one T. monococcum form, independent of a more or less uniform habit of this material.