TY - JOUR
T1 - Phytotoxic activity of Chinese violet (Asystasia gangetica (L.) T. Anderson) and two phytotoxic substances
AU - Suzuki, Masahiko
AU - Chozin, M. A.
AU - Iwasaki, Arihiro
AU - Suenaga, Kiyotake
AU - Kato-Noguchi, Hisashi
N1 - Funding Information:
We thank Dr. Ayu Vandira Candra, Bogor Agricultural University, Indonesia, for her kind help in preparing the plant materials. We also thank Professor Dennis Murphy, The United Graduate School of Agricultural Sciences, Ehime University, Japan for checking and editing the English of the manuscript.
Publisher Copyright:
© 2019 Weed Science Society of Japan
PY - 2019/3
Y1 - 2019/3
N2 - Chinese violet (Asystasia gangetica (L.) T. Anderson) is a perennial invasive weed belonging to Acanthaceae. Leaves of this weed have been suggested to possess phytotoxic activity. However, phytotoxic substances in this weed have not yet been reported. Therefore, the present study investigated phytotoxic activity of Chinese violet extracts and phytotoxic substances. The extracts of Chinese violet leaves inhibited the root and shoot growth of cress, lettuce, alfalfa, barnyard grass, ryegrass, and timothy, where the level of inhibition increased with increasing extract concentrations. Bioassay-guided separations of the extracts led to isolation of two phytotoxic substances, indole-3-carboxaldehyde and (6R,9S)-3-oxo-α-ionol. Indole-3-carboxaldehyde significantly inhibited the root and shoot growth of cress at concentrations ≥100 and 30 μmol L −1 , respectively, and concentrations of the substance required for 50% growth inhibition were 210 and 127 μmol L −1 for cress roots and shoots, respectively. The other substance, (6R,9S)-3-oxo-α-ionol, was reported to have strongly inhibited cress roots and shoots. The present results suggest that Chinese violet contains two phytotoxic substances indole-3-carboxaldehyde and (6R,9S)-3-oxo-α-ionol, and those substances may play an important role in the phytotoxic activity of Chinese violet.
AB - Chinese violet (Asystasia gangetica (L.) T. Anderson) is a perennial invasive weed belonging to Acanthaceae. Leaves of this weed have been suggested to possess phytotoxic activity. However, phytotoxic substances in this weed have not yet been reported. Therefore, the present study investigated phytotoxic activity of Chinese violet extracts and phytotoxic substances. The extracts of Chinese violet leaves inhibited the root and shoot growth of cress, lettuce, alfalfa, barnyard grass, ryegrass, and timothy, where the level of inhibition increased with increasing extract concentrations. Bioassay-guided separations of the extracts led to isolation of two phytotoxic substances, indole-3-carboxaldehyde and (6R,9S)-3-oxo-α-ionol. Indole-3-carboxaldehyde significantly inhibited the root and shoot growth of cress at concentrations ≥100 and 30 μmol L −1 , respectively, and concentrations of the substance required for 50% growth inhibition were 210 and 127 μmol L −1 for cress roots and shoots, respectively. The other substance, (6R,9S)-3-oxo-α-ionol, was reported to have strongly inhibited cress roots and shoots. The present results suggest that Chinese violet contains two phytotoxic substances indole-3-carboxaldehyde and (6R,9S)-3-oxo-α-ionol, and those substances may play an important role in the phytotoxic activity of Chinese violet.
KW - invasive weed
KW - phytotoxic activity
KW - phytotoxic substance
KW - plant growth inhibition
UR - http://www.scopus.com/inward/record.url?scp=85059862273&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85059862273&partnerID=8YFLogxK
U2 - 10.1111/wbm.12170
DO - 10.1111/wbm.12170
M3 - Article
AN - SCOPUS:85059862273
VL - 19
SP - 3
EP - 8
JO - Weed Biology and Management
JF - Weed Biology and Management
SN - 1444-6162
IS - 1
ER -