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18
Journal of Science and Technology in the Tropics (2010) 6: 17-21
Peninsular Malaysia. Chini 2 is a small town of the
Chini Felda scheme while Runchang is an Orang Asli
settlement in the Sungai Bebar area. The surrounding
of Sungai Bebar is peat swamp forest.
Male fruit flies were collected in the morning by
means of the sex attractants methyl eugenol (4-allyl-1,
2-dimethoxybenzene) and cue-lure (4-[4-(acetyloxy)
phenyl]-2-butanone). A small amount of each lure
was applied separately and away from each other on
the upper surface of a green leaf – the lures are very
effective and not affected by the leaf. Insects attracted
to the lures over a period of about 30 minutes were
collected with the aid of specimen tubes and plastic
bags. The specimens were preserved in ethanol in
the field and subsequently identified using current
literature and personal experience [1, 2, 5, 6].
Representative individuals were also photographed
in the field.
The diversity of the fruit flies was analysed using
BioDiversity Professional Ver 2.0 1997. Shannon-
Weiner index and Jaccard cluster analysis were
applied for this study.
RESULTS
The diversity and relative abundance of Dacinae
fruit flies collected in Chini 2, Runchang and Sungai
Bebar are listed in Table 1. Three species of methyl
eugenol group were present – Bactrocera carambolae
Drew and Hancock, Bactrocera papayae Drew and
Hancock and Bactrocera umbrosa (Fabricius). The
cue-lure attractant yielded four species – Bactrocera
infesta (Enderlein), Bactrocera melastomatos Drew
and Hancock, Bactrocera nigrotibialis (Perkins) and
Bactrocera cf tau.
For the methyl eugenol group all three species were
present in three localities, C2, R1 and R2. Two species
(B. carambolae and B. papayae) were collected in
C1 and only B. carambolae was found in R3, SB1
and SB2. Fruit flies of the cue-lure group were found
in five of the seven localities studied, not present in
C2 and R2 (Table 1). Bactrocera nigrotibialis was
the predominant species while B. infesta occurred in
quite large number in a river bank locality. The other
two species (B. melastomatos and B. cf tau) appeared
to be uncommon.
The Shannon-Weiner diversity index of the
Dacinae fruit flies revealed that R1 had the highest
H’ (0.58) followed by R2 (H’= 0.432) and C2 (H’=
0.401) (Table 1). Locations SB1 and SB2 yielded the
lowest H’ of 0.126 and 0.110 respectively (Table 1).
The Jaccard cluster analysis showed that R2 and C2,
and SB2 and R3 had respectively similarity of 100%
(Fig. 1).
DISCUSSION
An extensive trapping effort, using Steiner traps
baited with methyl eugenol or cue-lure and provided
with malathion, was conducted over 12-36 months in
the 1990s in Peninsular Malaysia and Thailand [7].
The trapped fruit flies were collected on a 1-2 week
Table 1. Species and number of Dacinae fruit flies collected in September 2009 by methyl eugenol
and cue-lure attractants from Chini 2, Runchang and Sg. Bebar (Pekan District, Pahang, Peninsular
Malaysia). C1, edge of secondary vegetation and fence of apartments in Chini 2; C2, abandoned village
house along main road and near housing estate in Chini 2; R1, near school and Orang Asli house with
orchard and secondary vegetation in Runchang; R2, near Orang Asli house in Runchang; R3, secondary
forest near river in Runchang; SB1, river bank near abandoned aquaculture area along Sg. Bebar; SB2,
forested area upstream from SB1 of Sg. Bebar.
Lure/species C1 C2 R1 R2 R3 SB1 SB2
Methyl eugenol
B. carambolae
B. papayae
B. umbrosa
Cue-lure
B. infesta
B. melastomatos
B. nigrotibialis
B. cf tau
22
58
2
28
26
5
12
16
8
1
1
1
4
6
12
63 1 3
Number of species 3 3 6 3 2 3 2
Shannon H’ 0.299 0.401 0.580 0.432 0.298 0.126 0.110
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