Development of a rapid method for identifying asparagus super-males using, N-(4-chloro-2-trifluoromethylphenyl)-Npropoxyacetamidine to induce flowering

In order to shorten the term for the identification of asparagus super-male plants, a method using N-(4-chloro-2trifluoromethylphenyl)-Nʹ-pro-poxyacetamidine (AM12) to induce flowering was developed. This method is conducted as follows: seeds from andromonoecious flowers are treated with AM12 to induce flowers to form on the seedlings, the new male flowers are crossed with normal female flowers, and the progeny seeds are again treated with AM12 to identify supermale plants from the sex ratio of the seedlings. Asparagus officinalis cv. `UC157ʹ seeds were treated with AM12. The seedlings were induced to flower at a high frequency in 25 days. The sex ratio of the plants was 1:1 and the male flowers had the pollen germination ability. One male flower induced by AM12 was crossed with female plant. This cross produced many progeny seeds. The seeds were treated again with AM12, and induced to flower. Two super-male plants were found among the progeny of andromonoecious flowers of the all-male cultivar `Gijnlimʹ within six months by this method. This method thus shortens the time for identifying super-males. Since the female flowers were fertile as well, AM12 treatment would also be effective for cross breeding.