
TY  - JOUR
A1  - Ismail, B. S. 
A1  - Kalithasan, K. 
T1  - Mobility of metsulfuron-methyl in tropical soils
JF  - Soil Research
JO  - Soil Res.
Y1  - 1997
VL  - 35
IS  - 6
SP  - 1291
EP  - 1300
KW  - sulfonylurea herbicides.
UR  - https://doi.org/10.1071/S97008 
N2  - The mobility of metsulfuron-methyl in 5 soil series with different organic contents was determined in a greenhouse as well as under natural conditions. In these studies, the movement and biological activity of metsulfuron-methyl were determined by the bioassay method using long bean as a bioassay species. Bioactivity and movement of the herbicide down the soil profile were inversely related to the organic matter content of the soil. Phytotoxic levels of metsulfuron-methyl were restricted to the 10-cm depth of the column containing Selangor Series soil except when it received 40 mL of water daily (depth, 10&#8211;15 cm). In Munchung Series, the phytotoxic level was also mainly in the 5&#8211;10 cm layer. However, when the column received 40 mL daily or every 4 days, the residue was detected in 15&#8211;20 cm and 10&#8211;15 cm zones, respectively. The phytotoxic level moved downward to the 20&#8211;25 cm layer both in Sogomana and Holyrood Series when 40 mL of water was given daily. A phytotoxic level of metsulfuron herbicide was detected in the 20&#8211;25 cm layer when the soil column containing Serdang Series was leached with 40 mL of water every 4 days or with 20 mL daily; the phytotoxic level was detected at a depth of 25&#8211;30 cm when this soil was watered daily with 40 mL. The downward movement of metsulfuron under natural conditions showed a pattern similar to that found under simulated conditions. Phytotoxic effects of the residue could be detected in the 25&#8211;30 cm and 15&#8211;20 cm zone of Serdang and Holyrood Series, respectively, after exposure to 20 days of rainfall (total 111&#183;9 mm). Phytotoxic residue in both Sogomana and Munchung Series soil was detected in the 10&#8211;15 cm layer, and in the 5&#8211;10 cm layer for Selangor Series soil, after exposure to 20 days of rainfall. After exposure to 40 days of rainfall (total 152&#183;8 mm) under natural conditions, the residue could be detected in the 15&#8211;20 cm layer of Selangor Series. The phytotoxic level moved deeper in soil with low organic matter after exposure to 40 days of rainfall. Fresh weight reduction was greater in the 20&#8211;30 cm layer in Serdang Series than in the top layer. 
ER  -

