HERBICIDES in Asian rice - IRRI books - International Rice ...

Table 2. Most common rice herbicides and herbicide
mixtures used in selected Asian countries.
Herbicide/mixture Country Trade names (no.)
2,4-D Thailand 120
Malaysia 98
Philippines 23
Indonesia 12
Sri Lanka 7
Bangladesh 6
Korea 5
2,4-D + butachlor
2,4-D + propanil
Butachlor
MCPA
Molinate + propanil
Propanil
Thailand
Thailand
Philippines
China
Korea
Sri Lanka
Malaysia
Thailand
Thailand
Sri Lanka
Malaysia
28
10
11
8
8
21
6
6
35
12
7
Thiobencarb Pakistan 5
a Source: 1991 ARSAP/CIRAD Regional Agro-pesticide Index for Asia
(same countries as Table 1). b lncludes only those countries where five
or more trade names are found.
spp. in Korea) following the decreased incidence of annuals that has resulted from
continuous use of herbicides that control annuals (i.e., phenoxys since 1950 and
chloroacetamides and thiocarbamates since late 1960 [Kim 1992, Park 19931).
New herbicides currently in advanced stages of development are expected to be
available soon: sulfamoylureas for postemergence broadleaf/sedgecontrol (Quakenbush
et al 1993, Murai et al 1993) and aryloxyphenoxypropionates or APPs
(fenoxaprop, cyhalofop) for postemergence grass control (Matsumoto et al 1993, Ray
et al 1993). Fenoxaprop, currently used for postemergence grass control in rice in the
United States (Khodayari et al 1989), is now used in some countries in Asia.
In general, the rice herbicides currently being used have adequate selectivity to
rice. However, rice is most susceptible to herbicide treatments at the same growth
stages as are weeds (i.e., from germination to the four-leaf stage). Herbicides for
broadleaf weeds and sedges have adequate physiological and morphological selectivity
to rice. Certain selectivity problems may occur with grass herbicides which do not
have adequate physiological selectivity to rice.
Integrated weed management in rice in Asia 149