Morphological structures and histochemistry of roots and shoots in Myricaria laxiflora (Tamaricaceae)

Abstract

Myricaria laxiflora (Tamaricaceae) is an endangered plant that is narrowly distributed in the riparian zone of the Three Gorges, along the Yangtze River, China. Using bright-field and epifluorescence microscopy, we investigated the anatomical and histochemical features that allow this species to tolerate both submerged and terrestrial environments. The adventitious roots of Myr. laxiflora had an endodermis with Casparian bands and suberin lamellae; the cortex and hypodermal walls had lignified thickenings in the primary structure. In the mature roots, the secondary structure had cork. The apoplastic barriers in stems consisted of a lignified fiber ring and a cuticle at the young stage and cork at the mature stage. The leaves had two layers of palisade tissue, a hyaline epidermis, sunken stomata, and a thick, papillose cuticle. Aerenchyma presented in the roots and shoots. Several Myr. laxiflora structures, including aerenchyma, apoplastic barriers in the roots and shoots, were adapted to riparian habitats. In addition, shoots had typical xerophyte features, including small leaves, bilayer palisade tissues, sunken stomata, a thick, papillose cuticle, and a hyaline epidermis. Thus, our study identified several anatomical features that may permit Myr. laxiflora to thrive in the riparian zone of the Three Gorges, China.

High effects of climate oscillations on population diversity and structure of endangered Myricaria laxiflora

“…The main reproductive mode of M. laxiflora is seeds or vegetative propagules through unidirectional water transmission, which has restricted the gene flow and genetic drift in the long distance dispersal ( Li et al., 2021 ). It is necessary to increase gene flow to prevent population degradation and maintain the maximum amount of genetic resources with appropriate strategies, which need to reduce inbreeding and artificially promote recruitment among the upstream and downstream populations.…”

De novogenome assembly ofMyricaria laxifloraprovides insights into its molecular mechanisms under flooding stress

“…Myricaria laxiflora (Tamaricaceae, 2n=24) is a perennial deciduous shrub belonging to the family Tamaricaceae [1,2]. It is a typical rare plant in the riparian zone, mainly distributed in the middle and upper reaches of the Yangtze River in China [1].…”

“…Myricaria laxiflora (Tamaricaceae, 2n=24) is a perennial deciduous shrub belonging to the family Tamaricaceae [1,2]. It is a typical rare plant in the riparian zone, mainly distributed in the middle and upper reaches of the Yangtze River in China [1]. M. laxiflora is a flood tolerant plant that sleeps in summer and autumn, reproduces in winter and spring, and grows on gravel beaches in the Yangtze River water level rise and fall zone [3,4].…”

Integrated Transcriptomic and Proteomic Analyses Uncover the Regulatory Mechanisms of Myricaria laxiflora Under Flooding Stress

“…Myricaria laxiflora (Tamaricaceae) is an endangered plant mainly distributed in the flood zone of the Yangtze River, China (Li et al, 2021). In the native habitats, M. laxiflora is completely submerged during the long-lasting flooding periods in summer and rapidly sprouts in the autumn and winter after the flooding (Wu et al, 1998;Wang et al, 2003).…”