and Integrated Pest Management - part - usaid

104 PIS'ICIDE MANAGEMENT AND HPM IN SOUIIIiAST ASIA
Phililpines with varying results. Trials in collaboration with the regional Crop
Protection Centers in the Philippines showed a 3.3% increase in net return with
61% succcssful cases (Waibel I 986a). Litsingcr (1984) reviewed results from
trial, comparing prophylactic treatmlents with ETs during the period 1976 to
1983, and found that overall, 52% of the cascs were successful, when data for all
pests were averaged, with a range from 29% (rice whorl maggot) to 71%
(case\vworml).
Rola and Kenmore (1986), in a study in Laguna, found a considerable
increase in net return with a high proportion of successful cases (Table 1).
In addition to the criteria used in Table 1, Icchnology such as economic
thresholds has also to be viewed from the perspective of risk. Risk i,;often
measured in terms of' the standard dcviation of net returns, with the assumption
that net returns are normally distributed. In Figure 1, it becomes obvious that
the ET technology increases average nci returns along with an increase in
standard deviation. This means that farmers have to 'pay'for the benefits
obtained by Iollowing economic thresholds in terms of a higher risk. For
example, in the 'hilippins (P. Kenmore, unpublishcd), for a S25 increase in net
return farmers would have to 'pay' merely $2 in standard deviation, while in
Thailand the ratio is almost 1:1. The practical implications are as follows: in a
given location a number of ftarmiers are doing perfectly well with thresholds,
while others are not. It might be (uite realistic to assume that fariers will look
at a number of early adopters before they decide to practice ETs by themselves.
It has been hypothesized, however, that fariners in developing countries are
only moderately risk averse, and would be willing to 'pay'two uniLs of standard
deviation for one unit in increased net returns (Ryan 1979). If we apply this
rule, the ET technology would seem to be accclptable under risk considerations.
On the other hand, wc find that while economic thresholds increase farmers'
profils, they do not significantly increase yields (Rola and Kenmore 1986).
LiLsinger (1984) concluded that Philippine rice production could be maintained at
Table 1. Economic assessment of economic thresholds in rice in two Southeast
Asian countries.
Country/(Sotrce)
Thai land m
Average increase of'
fanners' net return(%)
Percent of
succssful cases
ta
Philippines
4.2 80
(Waibel 1986a) t' 3.3 61
(Litsinger 19 84 )c
52
(Rola & Kenmore 1986)11 7.6
!'Results
82
of 40 farmers' fields 1985 dry season. bResults of 58 farmers' fields
1980-1981 dry and wet seasons. cCompared with prophylactic
dResults
treatments.
of 22 farmers fields 1986 wet season.