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

In order to shorten the term for the identification of asparagus super-maleplants, a method usingN-(4-chloro-2-trifluoromethylphenyl)-N'-pro-poxyacetamidine (AM12) toinduce flowering was developed. This method is conducted as follows: seedsfrom andromonoecious flowers are treated with AM12 to induce flowersto form on the seedlings, the new male flowers are crossed with normalfemale flowers, and the progeny seeds are again treated with AM12 toidentify super-male plants from the sex ratio of the seedlings. Asparagus officinalis cv. `UC157' seeds were treated with AM12.The seedlings were induced to flower at a high frequency in 25 days. Thesex ratio of the plants was 1:1 and the male flowers had the pollengermination ability. One male flower induced by AM12 was crossed withfemale plant. This cross produced many progeny seeds. The seeds weretreated again with AM12, and induced to flower. Two super-male plantswere found among the progeny of andromonoecious flowers of the all-malecultivar `Gijnlim' within six months by this method. This method thusshortens the time for identifying super-males. Since the female flowers werefertile as well, AM12 treatment would also be effective for cross breeding.