and Integrated Pest Management - part - usaid

ECONOMICS OFIPC IN RICE IN SOUTIIlEAST ASIA 109
Thailand, we collected data on agronomic practices and pests 'iswell as beneficial
population.;. We grouped these practiccs (Table 4) for all significant differences
in pest levels. For example, in the province of Chachoengsao, we found that
farmers who apply more than the recorimended level of nitrogen have
significantly higher population level-, of green leallopper Nephotettix spp. anti
rice leaffolder Cnaphalocrocisinedinalis. Shezald we recomniend the farmers
concernecd to reduce their fertilizer level? In the province of Chai Nat as another
example, we found that farmers who followed the tr'nsplanting method
experienced a significantly higher stemborer infestation. Should they shift to
direct seeded rice? We are well aware that result,, as shown in Table 4 must be
treated with extreme care, more so because data are coll.2cted from farmers' fields
and not under controlled conditions. Also they represent only a short period of
time. We need to have more of such information in quantitative terms and to
use this information for resource allocation and goal achievemealt.
We cannot refrain from asking another equally impoitant question. Flow do
farmers assess the possible effects of changing agronomic practices?
In the Thai-German Plant Protection Program (TG-PlPP), we are at present
conducting a study on the decision making process of farmers. In Table 5, a
farmer's expectations from changing his variety is presented (Tuetinghoff 1987,
pers. comn.). The two varieties under consideration were assessed by the farmer
as being equally susceptible to some insect pests while the resistanct in the
second variety was believed to be effective against rice blast Pyriculariaoryzae.
The farmer expected the resistan' variety to command a lower price which,
however, he expected to be compensated for by its higher yield due to the nonoccurrence
of rice blast. He also expected the effect of applying fertilizer to be
higher than in the non-resistant variety. On the other hand, he expected a higher
yield loss from not spraying insecticides in the non-resistant variety and equal
loss from not applying herbicides. It is remarkable that he placed herbicides
Table 5. A farmer's expectation from changing from a non-resistant to a
resistant variety.
Non-resistant Resistant
variety variety
Expected price (Eaht/tang) 21.5 20.5
Expected yield (tangrai) 72 82
Yield increase from fertilizer 21.4 24.6
application (tanirai) a1
Yield increase from insecticide 31.6 26.9
application (tang/rai)a
Yield increase fron herbicide 32.6 32.4
application (ang/rai)a
aMeasured in terms of yield reduction in case input would not be applied.