Plasticity in phenotype and biomass allocation of Vetiveria zizanioides under long-term alternate flooding and drying

Vetiveria zizanioides（hereafter vetiver） is one of the few species that survived in the water-level fluctuation zone of the Three Gorges Reservoir. Although the introduction, cultivation, and research of vetiver in China has a history of decades, little is known about the adaptive strategies of vetiver that under the conditions of long-term flooding and drying periodic changes. Therefore, the plasticity in phenotype and biomass allocation of vetiver planted in altitude zones of 166-169 m, 169-172 m and 172-175 m above sea level in the water-level fluctuation zone of the Wushan section of the Three Gorges Reservoir in 2008 were studied in 2016. The results showed that:（1） the morphological traits（e.g.,number of tillers, average plant height, number of internodes, length of internodes, number of leaves per tiller, number of leaves per bush and length of leaves） of vetiver in altitude zone of 166-169 m were all lower than those in altitude zones of 172-175 m and 169-172 m. The number of internodes in altitude zone of 166-169 m was significantly different（P