Crossability between C. arabica and C. kapakata and cytological analysis of the hybrid

The ability of C. kapakata to cross with C. arabica was analysed in the present paper. The ratios between seed-ovules, seedling-seeds and seedling-ovules were taken into account in order to evaluate the kinhood of the two species. It was found that the crossing rate was higher when C. arabica, the tetraploid species, was used as female. In the backcrosses it was found that the hybrid could not be crossed with C. kapakata, while C. arabica crosses in both directions with the F, hybrid. The hybrids were morphologically intermediate to both species. Observations were made about the meiosis of one of the hybrids. The chromosome associations were in average 1.33III 9.45II and 10.07I, for diakinesis and first metaphase. The distribution of the chromosomes during anaphase as well as the tetrades are abnormal. The pollen grains contain more frequently from 13 to 17 chromosomes. The hybrids between C. arabica and C. kapakata have been used as bridge for transferring drought resistance of C. kapakata to the cultivars of C. arabica.