Physiological Changes During Cold Storage of Lilium ledebourii (Baker) Boiss. Bulb, a Rare Indigenous Species to Iran

Lilium ledebourii is a native and endangered rare species in Iran. It requires a cold period for proper growth and flowering. This experiment was performed to investigate the effects of cold storage on changes of endogenous abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellic acid (GA3), sucrose, fructose, glucose, and total saponin during dormancy of Lilium ledebourii bulbs. The bulbs of lily were stored at 1 or 7 ºC, for 0, 30, 60, 90, and 120 days, and after each period removed from storage and analyzed using HPLC system. The results indicated that, cold storage at 1 ºC for 120 days decreased the levels of ABA while, 7 ºC in the same duration increased its content, slightly. The levels of IAA increased at 1 ºC storage, while remained almost constant at 7 ºC. Cold treatment at 1 ºC increased the levels of GA3, while storage at 7 ºC caused slight decrease in its content. Sucrose and fructose concentrations increased in both temperatures during the storage, while minor reduction in glucose content was observed. Storage at 7 ºC for 120 days induced the highest content of total saponin. The magnitude of changes in hormones and soluble sugars measured at 1 ºC was greater than that at 7 ºC.