Molecular mechanisms underlying the phenotypic changes on root growth and flowering of Tamarix chinensis parasitized by Cistanche tubulosa

Cistanche tubulosa (Schenk) R. Wight is a valuable traditional Chinese medicine in China, which is exclusively alloparasitic on the roots of Tamarix spp. Parasitism usually causes a series of morphological and physiological changes on the host plants. However, the effects of C. tubulosa parasitism on root growth and flowering of Tamarix chinensis have rarely been studied. To understand the molecular mechanism, the endogenous hormone levels and gene expression profile in T. chinensis roots and leaves parasitized and unparasitized by C. tubulosa were determined and sequenced. Phytohormones and key flowering regulating genes synergistically caused non-flowering phenotype in infected T. chinensis. The results revealed the underlying mechanisms of phenotypic changes in infected T. chinensis and given the first molecular insights into the flowering regulation of plant parasitism.