The bulb of Lilium longiflorum Thunb. cv. Nellie White were harvested in August, September, and October from field in Oregon and sent to St. Paul. Bulbs were also obtained in July from greenhouse forced material. These bulbs were used to study the types of dormancy.
We propose that dormamcy of L. longiflorum can be divided into innate dormancy, which is present in the mother scales of early harvested bulb and imposed dormancy, which is present in the outer daughter scales. The criteria of dormancy is based on the sprouting response.
Although dormancy can not be investigated independantly from the factor of immaturity, dormancy could be induced in both long and short photoperiod conditions. These two types of dormancy are removed by lighting bulb scales.
As the bulb harvest dates were delayed, the level, or degree of dormancy bacame weak. Sprouting of October harvested bulbs was not influenced by scale removal or by light treatment.
We propose that the maturity factor was located in the mother and other daughter scales.
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