Arsenic Accumulation and Physiological Response of Three Leafy Vegetable Varieties to As Stress.

Arsenic (As) in leafy vegetables may harm humans. Herein, we assessed As accumulation in leafy vegetables and the associated physiological resistance mechanisms using soil pot and hydroponic experiments. Garland chrysanthemum (Chrysanthemum coronarium L.), spinach (Spinacia oleracea L.), and lettuce (Lactuca sativa L.) were tested, and the soil As safety threshold values of the tested leafy vegetables were 91.7, 76.2, and 80.7 mg kg−1, respectively, i.e., higher than the soil environmental quality standard of China. According to growth indicators and oxidative stress markers (malondialdehyde, the ratio of reduced glutathione to oxidized glutathione, and soluble protein), the order of As tolerance was: GC > SP > LE. The high tolerance of GC was due to the low transport factor of As from the roots to the shoots; the high activity of superoxide dismutase, glutathione peroxidase, and catalase; and the high content of phytochelatin in the roots. Results of this work shed light on the use of As-contaminated soils and plant tolerance of As stress.

The complete chloroplast genome of Acanthopanax brachypus (Araliaceae), a famous medicinal plant in China.

Acanthopanax brachypus (Araliaceae) is an important medicinal plant originated from China. Here, we reported the first chloroplast genome sequence of A. brachypus. The plastome of A. brachypu is 156,802 bp in length, including a large single-copy (LSC) of 86,742 bp, a small single-copy (SSC) of 18,184 bp, and a pair of inverted repeat regions (IRa and IRb) of 25,938 bp. It contains 113 unique genes consisting of 80 protein-coding genes, 29 tRNA genes, and 4 rRNA genes.

The complete chloroplast genome of Tagetes erecta (Asteroideae), a wildly cultivated ornamental plant.

Tagetes erecta (Asteraceae) has been wildly cultivated as ornamental and medicinal plant. Here, we reported the first chloroplast genome sequence of T. erecta. The chloroplast genome size is 152,065 bp with GC content of 37.4%, including a large single-copy (LSC) of 83,895 bp, a small single-copy (SSC) of 18,065 bp, and a pair of 25,048 bp IR (inverted repeat) regions. A total of 132 genes were annotated including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The phylogenetic analysis revealed that T. erecta belongs to the subfamily Asteroideae.