ObjectiveLilium spp. is one of the main commercial flowers in the world which possesses both high ornamental and economic value. However, the current leading cultivars of Lilium Oriental hybrid are lack of drought and saline-alkaline tolerance thus it is crucial to improve the above properties.

MethodBased on four-year subculture and one-year greenhouse culture, the stability of the target gene and changes of the phenotypes and physiological indices were tested for the single copy transformation line L89 and double copy line L31 with the P5CS-F129A gene of Lilium Oriental hybrid 'Sorbonne'. The Southern blot and cDNA detection showed stable inheritance of the target gene.

ResultThe results of drought stress treatments demonstrated that the leaves of both transgenic lines contained higher proline content than the common 'Sorbonne', of which L31 contained the highest proline level. Though the relative leaf ion leakage of both transgenic lines and the common 'Sorbonne' rose in the drought stress process, the transgenic lines showed lower relative leaf ion leakage than the common 'Sorbonne'. After the second watering, the relative leaf ion leakage of both transgenic lines recovered to normal level, while the common 'Sorbonne' didn't. In the aspect of phenotype, both L89 and L31 grew well after the second watering, showing no obvious damage on growth, while the common 'Sorbonne' showed severe leaf etiolation and growth retardation.

ConclusionThe above research indicated that the P5CS-F129A transgenic gene lines possessed stronger drought tolerance which would be significant to the cultivation of new cultivars of stress-tolerant lily.