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Polyploidization plays an important role in plant adaption to adverse environments, but the mechanism by which polyploidization confers adaptation to cold stress remains elusive. Here, autotetraploid strawberry (2n = 4x = 28) was successfully synthesized from wild strawberry (Fragaria nilgerrensis; 2n = 2x = 14) using a primary meristem processing technique. The autotetraploid plants exhibited a higher resistance to cold stress compared to their parental diploids, revealed by a series of physiological-biochemical examinations. Transcriptome analysis showed that expression pattern changes of genes in several pathways were the key contributors to the high cold resistance of autotetraploid strawberry. These main players included Ca2+ signal transduction, transcription factors (TFs), reactive oxygen species (ROS) scavenging enzyme, phenylpropanoid biosynthesis, abscisic acid (ABA) signaling and carbohydrate metabolism. The coordinate action of these factors enhanced the antioxidant defense system and protected the integrity of membranes and cellular organelles. Notably, gene co-expression network analysis (WGCNA) demonstrated that four hub genes (regulating cinnamyl-alcohol dehydrogenase (CAD), peroxidase (POD), caffeoyl-CoA O-methyltransferase (CCoAMT) and calmodulin-like protein (CML)) function much importantly in the network regulating this high cold resistance. Therefore, a model is proposed to elucidate the regulatory mechanisms of high cold resistance in the autotetraploid strawberry. The present findings provide new insights into understanding the complex regulatory network responsible for enhancing cold resistance in ployploid plants.

Visible-light photodegradation test revealed that B and Zr co-doping can raise the photocatalytic ability of the undoped TiO 2 by a fold. XRD crystallography and Raman phonon spectroscopy measurements suggest that the Zr 4+ ions replace the Ti 4+ ions while the B 3+ ions occupy the interstitial sites, expanding the unit-cell volume and reducing crystallite size. The incorporation of interstitial boron dopants creates oxygen vacancies (Ov ) and reduce Ti 4+ to Ti 3+ to form [Ov -Ti 3+ ] + , which traps the carriers and prolongs carrier lifetime. Moreover, Zr 4+ ions replace Ti 4+ ions and form impurity levels, which could improve visible light response. The co-doped samples are benefited from both B interstitials and Zr substitutes.

Menispermum dauricum is a woody liana with great medicinal value. In the current study, we assembled the first chloroplast (cp) genome of M. dauricum. The whole chloroplast genome is 158,623 bp in ...

Based on molecular data, a new species, Myriolecis altunica, is described, and Lecanora caesioalutacea is placed in the genus Myriolecis (Lecanoraceae, Ascomycota). Myriolecis altunica is characterized by having a continuous, ashy brown thallus, with lobulate margins, apothecia with blackish disc and margin, with the disc whitish pruinose, and the absence of secondary substances. Myriolecis caesioalutacea has an ashy gray thallus and heavily pruinose, almost white apothecia, and contains xanthones (2,7-dichlorlichexanthone). The species was first reported as Lecanora caesioalutacea H.Magn. from Gansu, China, but is here shown to belong in the genus Myriolecis. Phylogenetic analyses based on ITS separately and on a 6-locus combined analysis (ITS, LSU, mtSSU, RPB1, RPB2, MCM7) both support placement of these two species in Myriolecis. The taxa are described and illustrated, and their distribution and ecology are briefly discussed.

Lycium ruthenicum is a precious desert plant with high medicinal and ecological values. It contains rich anthocyanins, which are safe natural pigments and could be used for natural food colorants. In this study, the complete chloroplast (cp) genome of L. ruthenicum was assembled on the basis of next generation sequencing. The whole genome is 154,996 bp in length, including two single copy regions (LSC: 85,993 bp and SSC: 18,213 bp) and two inverted repeat regions (IR: 25,395 bp). The overall G + C content of the genome is 37.9%. The cp genome consists of 111 unique genes, including 30 tRNA genes, 4 rRNA genes and 77 protein-coding genes. Phylogenetic analysis indicates that L. ruthenicum is closely clustered with Atropa belladonna, Przewalskia tangutica, and Scopolia parviflora.