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Root border cells (RBCs) originate from the root tip epidermis and surround the root apices. In this study, we evaluated the developmental characteristics and the roles of RBCs in protection of root apices of cucumber and figleaf gourd seedlings from CA toxicity. The formation of RBCs and the emergence of the root tip occurred almost simultaneously in root apices of cucumber and figleaf gourd seedlings. CA ranging from 0 to 0.25 mol L−1 inhibited root elongation and decreased root cell viability in the root tip, moreover the inhibitory effects of CA were more significant in the CA-sensitive cucumber than in the CA-tolerant figleaf gourd. Removal of RBCs from root tips led to more severe CA induced inhibition of root elongation and decline in root cell viability. Increasing CA levels and treatment time decreased the relative viability of attached and detached RBCs. CA also induced a thicker mucilage layer surrounding attached RBCs of both species. Additionally, a significantly higher relative cell viability of attached RBCs and thicker mucilage layers were observed in figleaf gourd. These results suggest that RBCs play an important role in protecting root tips from CA toxicity.

Three new phytane-type diterpene-γ-lactone shaliuin I (2), shaliuin II (3) and shaliuin III (4) were isolated along with thirteen known compounds from twigs of Salix cheilophila omitted (Chinese name "Shaliu", Salicaceae). The structures of three new compounds have been established on the basis of spectroscopic methods and 2D NMR techniques.

A new cyclohexanone derivative, methyl 5α,6α-epoxy-1-hydroxy-2-methoxy-4-oxocyclohexanacetate, along with five known cyclohexanones were isolated from the aerial parts of Senecio argunensis. Their structures were elucidated on the basis of spectroscopic methods, including IR, EI-MS, HR-ESIMS, 1D NMR and 2D NMR.

The title compound, [Ag(C(7)H(4)ClO(2))(C(6)H(8)N(2))(2)], is a mononuclear silver(I) complex. The Ag(I) atom is three-coordinated by two pyridine N atoms from two 5-methyl-pyridin-2-ylamine ligands and by one O atom of a 4-chloro-benzoate ligand, forming a distorted T-shaped coordination. In the crystal structure, the mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains running along the b axis.

In the title complex, [Zn(C(3)H(3)O(2))(C(27)H(27)N(7))](ClO(4))·C(3)H(7)NO·1.5CH(4)O, the Zn(II) ion is five-coordinated by four N atoms from a tris-(1-methyl-benzimidazol-2-ylmeth-yl)amine (Mentb) ligand and one O atom from an acrylate ligand in a distorted trigonal-bipyramidal geometry with approximate mol-ecular C(3) symmetry. The atoms of the acrylate ligand are disordered over two sites, with approximate occupancies of 0.84 and 0.16. In addition, a methanol solvent mol-ecule is disordered over two sites with equal occupancies. In the crystal structure, the full-occupancy methanol is linked to a dimethyl-formamide mol-ecule by an inter-molecular O-H⋯O hydrogen bond.