and Integrated Pest Management - part - usaid

292 PE'STICIDE MANAGMitwr AND IPM INSOIflhIEAsT ASIA
More than 100 insecticide trade names belonging to the organophosphate,
carbamate, synthetic pyrethroid compounds and its combinations, are registered
for food crop protection in the country (Anon. 1985). The ratios of
organophospha!.- and carbamate compounds expressed in percentages are shown
in Table 1. The yearly increase in total amount of insecticides distributed for the
intensification program of rice and secondary crops is shown in Figure 1 and the
total land planted with rice is shown in Figure 2. Despite the cultivation of
resistant varieties due to fear of crop failure, many farmers are applying
insecticides routinely, and very often, excessively.
INSECTICIDE RESISTANCE
Insecticides have been well adopted by farmers and are widely used because
of their quick effects against insect pests. On the other hand, it is well known
that large-scale and inappropriate use of insecticides may create serious
environmental and ecological pioblems. The continuous use of insecticides has
also led to the development of resistar, c i::rminy places (Nagata and Morita
1974).
The first evidence of insecticide resistance in Indonesia was recorded in 1951,
when DDT became ineffective against the diamondback moth Plutella xylostella.
This compound was replaced first by Toxaphene, and then by BHC. Up to
1982, no study was done on insect resistance even though organophosphates and
synthetic pyrethroids were intensively used for controlling the insect.
In 1982, Dandi et al. (1982) reported that P. xylostella collected from
Lembang, West Java, were resistant to permethrin, and Iman et al. (1985)
recorded difference! in insect susceptibility to organophosph;ita and synthetic
pyrethroid depending on the locality and origin of insects. Detection of
insecticide resistance of rice pests has focused on BPH, the number one pest in
Indonesia, which has undergone selection pressure with several insecticides.
In 1977, we initiated a study on BPII resistance to insecticides. Eight
populations of BPH collected from West and Central Java were treated
individually with diazinon and carbaryl using a micro topical application method.
Based on the LD 50 values, no differences of susceptibility level among the
Table 1. The ratio of organophosphate and carbamate compounds distributed in
Indonesia, expressed in percentages.
Compound 1978 1979 1980 1981 1982 !983 1984 1985 1986
Organophosphate
86 85 78 72 72 71 70 70 65
Carbamate 14 15 22 28 28 29 30 30 35
Source: Badan Pengendali Bimas, Jakarta.