field survey on fruit flies (diptera: tephritidae) in …...62 res. bull. pl. prot. japan no.54...

───────────────────────────────────────────────────────────1) Plant Protection Division (PPD), Yangon2) Plant Protection, Department of Agriculture, Ayeyarwaddy Region3) Fukuoka City, Fukuoka Pref., Japan

Res. Bull. Pl. Prot. Japan No. 54：61～ 67（2018）

Field Survey on Fruit Flies (Diptera: Tephritidae) in Mango Orchards in Myanmar

Shigehito NAKAHARA, Mu Mu Thein 1), Khin Nyunt Yee 1), Shaine Shane Naing 1), Win Soe 2), Than Htiek 2) and Mitsuru KATAYAMA 3)

Research Division, Yokohama Plant Protection Station. 1-16-10 Shin-yamashita, Naka-ku, Yokohama, 231-0801 Japan.

Abstract: A survey on fruit flies in Myanmar was conducted by the Japan International Cooperation Agency (JICA) in

collaboration with the national governments of Myanmar and Japan in 2014. The objective of this survey was to acquire

information on the Bactrocera fruit fly species present in Myanmar for possible phytosanitary concerns when mangoes are

exported to other countries. In the survey, more than seventy thousand Bactrocera fruit fly specimens were collected from

four major mango production areas, namely the Yangon, Bago and Mandalay regions and Shan State by fruit sampling

and adult fly trapping. The subsequent identification revealed that B. correcta and B. dorsalis were distributed in mango

orchards in all four areas. In addition to these, three other species, B. carambolae, B. zonata and B. cucurbitae, were found

present while the detected numbers were substantially smaller than the two previously mentioned. While these three species

have the potential to infest and damage mango fruits as well, a significantly lower number of flies were caught in each trap

per day (FTD) from these three species than the two aforementioned species. In addition, B. zonata and B. cucurbitae were

not found in the sampled fruits. Based on this analysis, it was concluded that B. correcta and B. dorsalis are two major

species present in mango production areas of Myanmar, and can be of phytosanitary concern to trade partners in the export

of mangoes, and other species could be found in commercial mangoes for which further detailed study is necessary.

Key words: Bactrocera, Mango, Field survey, FTD, Trap

Short Communication

Introduction

　Fruit flies (Diptera: Tephritidae) are recognized worldwide as

serious insect pests of fruits and vegetables, and they are a major

obstacle in the international trade of fruits. In Myanmar, certain

species of fruit flies have caused damage and considerable yield

losses in mangoes (Mangifera indica). A project formulation survey

was conducted by the Japan International Cooperation Agency

(JICA) in 2014 in order to study basic information necessary for

technical cooperation concerns with the export of fresh mangoes

from Myanmar to Japan. One of the main activities was to identify

fruit fly species that may be parasitic on fresh mangoes. Surveys

to ascertain fruit fly pests are an important component in research

seeking the lifting of import bans, and play key roles in the selection

of quarantine treatments. In Myanmar, the Australian Agency for

International Development (AusAID) (2006 – 2008) and the Plant

Protection Division of Myanmar (PPD) (2010 – 2011) collected

various plant pests including fruit flies to obtain general information

regarding insect pest fauna. The reports from these efforts, however,

did not focus on phytosanitary perspectives, and relevant information

has not been published in detail. Also, no follow-up surveys for fruit

flies have been conducted in Myanmar. Therefore, this study will

be the first report on the species composition of fruit flies from a

phytosanitary perspective of fresh mango exports.

Materials and Methods

　Two types of approaches, i.e. fruit sampling and adult fly

Res. Bull. Pl. Prot. Japan62 No.54

trapping, were taken in two phases; the first was from January 20 to

February 21, 2014 (dry season) and the second was from May 12

to June 18, 2014 (monsoon season: mango harvest season is from

April to June). The survey was conducted in 20 mango orchards

in eight townships over five areas (Fig 1). Two of those orchards

are of national institutes, namely the Vegetable and Fruit Research

Development Center PPD (VFRDC) in Yangon Region, and Htone

Bo Farm of Department of Agriculture (DOA) in Mandalay; and the

other 18 orchards are private farms (Fig. 1, Table 1). The five areas

were primary mango production areas and were selected with the

cooperation of the PPD. Some orchards had mixed vegetation with

other fruit trees such as papaya and guava and/or various vegetables

such as gourd, chili pepper and green beans. GPS data were recorded

at representative points of each orchard using a Wireless GPS

Logger M-241 (Holux Technology Inc.). The resultant geographical

distribution of the orchards is shown in Table 1. (1) Fruit sampling (mangoes)

　 A total of 94 damaged fallen mango fruits were collected on 18

orchards (not including two orchards in Patheingyi Township). After

collection, the fruits were placed for a week in plastic containers

with small square synthetic mesh in which sand was laid on the

bottom of the containers to facilitate pupation. The containers were

kept at the fruit fly laboratory (at room temperature) at the PPD in

Insein, Yangon Region. Fruit juice and mold were removed from the

damaged fruits, as appropriate. About one week after collection, each

of the fruit were cut open and examined to confirm the presence of

fruit fly larvae. For the fruits collected from the southern part of Shan

State, the fruit fly larvae emerged after the authors left Myanmar;

therefore, the specimens were sent to Japan through the JICA.(2) Adult fly trapping

　40 pairs of traps were placed in five townships in Phase 1 (dry

season), and 46 pairs of traps in eight townships in Phase 2 (monsoon

season) (Table 1).

　These traps were simple versions of the suggested Lynfield type

(IAEA, 2003), which consist of a clear, cylindrical polyethylene

terephthalate container measuring 9.5 cm high with a 13 cm diameter

base lid and 10 cm diameter top (Fig. 2). The trap has three openings

on the sides for fruit fly entry. Two types of synthetic attractants were

used, namely methyl eugenol and cue-lure, to which insecticide was

added (Malathion, 7.5-8.0%) so that trapped fruit flies would not

escape. A cotton wick saturated with the malathion-added attractants

was hooked with wire in the center of the trap. In addition, sticky

glue (Tree Tanglefoot Insect Barrier, CONTECH, USA) was set

above the trap to thwart ants. Two to five pairs of traps were installed

in every orchard at a height of about 1.5m and they were arranged

70-100m apart from each other. The trapped fruit flies were collected

approximately two weeks after trap installation. For the orchards in

Taunggyi and Nyaung Shwe in southern Shan State, however, the

sample fruits were collected one or two days after installation due to

the limited time of the authors’ stay in the area. (3) Identification

　Morphological identification of the fruit flies was done both in the

laboratory of the PPD in Insein, Yangon Region and in the Nagoya

Plant Protection Station in Japan. White and Elson-Harris (1992)

and Drew and Romig (2013) were mainly used as references for

identification, while other papers were referred to as needed. For

some samples of Bactrocera dorsalis species complex, researchers at

the Plant Pest Identification Section of the Yokohama Plant Protection

Station were consulted.

Fig 1. Survey locations in Myanmar. The letters correspond to Table 1.

++

+

++AB

CD

E

18 N

24 N

12 N

96 E

Yangon

Mandalay

Bago

Naypyidaw

Shan State

Fig 2. The trap used in the survey.

Nakahara et al., Field Survey on Fruit Flies in Myanmar. 63Ｄecember. 2018

(4) FTD

　To evaluate the phytosanitary significance as pests to mangoes,

FTD (Fruit flies/Trap/Day) values were calculated and compared

among research areas and locations. FTD is a population index

suggested by the IAEA (IAEA, 2003), which indicates the average

number of flies captured per trap per day in a specified period. While

no statistical analysis was undertaken, the general trend will be

discussed later in this paper.

Results

(1) Fruit sampling (mango)

　The collected mango fruits were mainly of the Sein Ta Lone

variety. As a result of rearing the larvae, 2,556 adult flies emerged

in total (Table 2), which were identified as being from three species,

namely B. carambolae, B. correcta and B. dorsalis, and numbering

37, 1,102, and 1,417, respectively. B. dorsalis was detected at all

orchards, while more flies emerged from fruit collected from southern

Shan State (109 adult flies per fruit on average).

　B. correcta was detected from most orchards, and 63 adult flies

emerged on average from damaged fruit collected in Bago Region.

For B. carambolae, internationally well known as a serious pest of

mangoes, only 37 adult flies were detected from one orchard in Bago

Region (Table 2). B. zonata, another species well known as a serious

pest, was not detected. B. cucurbitae was also not detected in this

survey.

(2) Adult fly trapping

　The fruit fly species trapped, vegetation type and geographical

information are shown in Table 1. A total of 68,352 individuals from

five species (B. carambolae, B. correcta, B. dorsalis, B. zonata and B.

cucurbitae) were collected using two attractants (Table 2). While the

species composition somewhat varied from one orchard to another,

B. correcta and B. dorsalis accounted for the most individuals in any

survey location in both the dry season and monsoon season using

methyl eugenol. B. cucurbitae was trapped using cue-lure in all five

research areas in the Yangon, Bago and Mandalay regions and two in

Shan State. As Table 1 indicates, no correlation was observed between

the fruit fly species trapped and the orchard height above sea level.

　FTD values of the five Bactrocera species in each orchard are

shown in Fig. 3. Because the survey was conducted only in Phase

2 for three orchards in Mandalay and all orchards in southern Shan

State, data for the dry season does not appear in this figure. For

four species excluding B. cucurbitae, FTD values in the monsoon

season were evidently higher than those in the dry season. Relatively

high FTD values of 241 and 131 for B. dorsalis were observed in

Mandalay Region and southern Shan State, respectively. Similarly,

relatively high FTD values of 54.4 and 44.8 for B. correcta were

also observed in Mandalay Region. However, FTD values of B.

carambolae and B. zonata collected in all research areas were

significantly lower than those of B. dorsalis and B. correcta. The

highest FTD value of B. cucurbitae, 2.96, was detected at orchard

No. 6. in Mandalay in the monsoon season. While the FTD of B.

cucurbitae generally tended to be high in the monsoon season as was

observed with the other four Bactrocera species, those on several

orchards in Yangon and Bago were higher in the dry season than the

monsoon season.

Discussion

The five species detected in the survey are those which have been

reported as the species widely distributed in Asian countries such as

China, Thailand and Malaysia (Drew and Hancock, 1994; Drew and

Romig, 2013). It was reconfirmed in this study that the species well-

known as important pests of mango cultivation are also distributed

in Myanmar. It also became clear that the occurrence density and

infestation rate differed by species. Among the five species, B.

correcta and B. dorsalis were trapped at all orchards irrespective of

height above sea level or surrounding vegetation, and this implies

that the density of both species is high and they are the main pests

of mango fruits in Myanmar. While the detected number of B.

dorsalis was 3.6 times greater in the monsoon season, this should be

cautiously interpreted as the response of B. correcta against methyl

eugenol being lower than that of B. dorsalis (Kamiji et al., 2017),

and B. correcta could be a dominant species. For B. carambolae and

B. zonata, FTD values of both species were lower than 1.0 in most

orchards. Their occurrence density seems close to the prevalence

condition suggested in the Trapping Guidelines for Area-Wide Fruit

Fly Programs (IAEA, 2003), which is defined as a range between

0.1 and 1.0. Therefore, possible damage caused by these species

can be reduced further by performing appropriate pest control in the

field. From the above, two species, B. correcta and B dorsalis, can

be a major obstacle to international trade. The population densities

in the dry season were observed to be clearly lower than in the

monsoon season for all species except B. cucurbitae, for which the

opposite situation appeared in several orchards in Yangon and Bago.

This indicates the relative tendency for population densities of B.

cucurbitae to be high in the dry season, as previously reported in

northern Thailand (Clark et al., 2001). This is likely due to seasonal

differences in the availability of suitable host plants. In addition

to this difference in availability, other factors such as temperature,

rainfall and humidity have been suggested to affect fruit fly

populations (Kawashita et al., 2004; Felicia et al., 2013; Danjuma

et al., 2014), and further study is necessary to have more detailed

and comprehensive understanding of seasonal occurrence patterns

throughout the year.

Only three species, B. carambolae, B. correcta and B. dorsalis,

were detected from the sampled fruits. The latter two, B. correcta

and B. dorsalis, were detected from most fruits that we collected

in the field. It was also observed that the two species were found

in mango fruits collected from open spaces of temporary storage


Tabl

e 1.

Fru

it fly

spec

ies t

rapp

ed a

nd v

eget

atio

n ty

pes a

t eac

h lo

catio

n.

Phas

e 1

Phas

e 2

1Y

-1～

5Y

-1～

5E9

6°17

'27.

, N17

°9'1

3.-1

++

++

+C

aric

a pa

paya

, Citr

us m

axim

a, H

yloc

ereu

s und

atus

, Man

gife

ra in

dica

,M

usa

spp.

, Pha

seol

us v

ulga

ris,

Pru

nus

sp.,

Sech

ium

edu

le,

Zizi

phus

mau

ritia

na2

Y-6～

7Y

-6～

7E9

6°17

'38.

, N17

°8'2

8.2

++

++

+M

angi

fera

indi

ca3

B-1～

2B

-1～

2E9

6°25

'28.

, N17

°13'

23.

10+

++

+C

itrus

max

ima,

Dur

io zi

beth

inus

, Man

gife

ra in

dica

4B

-3～

6B

-6～

8E9

6°28

'01.

, N17

°13'

34.

15+

++

++

Car

ica

papa

ya, C

itrus

max

ima

, Dur

io zi

beth

inus

, Hyl

ocer

eus u

ndat

us,

Psid

ium

gua

java

, M

angi

fera

indi

ca5

B-7～

10B

-3～

5E9

6°26

'57.

, N17

°12'

39.

29+

++

+Ar

toca

rpus

het

erop

hyllu

s, D

urio

zibe

thin

us, M

angi

fera

indi

caA

mar

apur

a To

wns

hip

(Man

dala

y R

egio

n)6

M-1～

4M

-1～

4E9

6°04

'01.

, N21

°47'

01.

83+

++

+M

angi

fera

indi

ca

7M

-7～

9M

-10～

12E9

6°11

'37.

, N21

°30'

08.

102

++

++

+M

angi

fera

indi

ca8

M-1

0～11

M-1

3～14

E96°

11'5

1., N

21°3

0'10

.10

4+

++

++

Man

gife

ra in

dica

9M

-12～

14M

-15～

17E9

6°12

'14.

, N21

°30'

44.

117

++

++

+M

angi

fera

indi

ca10

M-5～

6M

-5～

6E9

6°03

'30.

, N21

°48'

44.

91+

++

+M

angi

fera

indi

ca11

M-1

5～17

-E9

6°12

'08.

, N21

°52'

41.

90+

+Ae

gle

mar

mel

os, M

angi

fera

indi

ca, Z

izip

hus m

auri

tiana

12M

-18～

20-

E96°

12'1

4., N

21°5

2'43

.96

++

Man

gife

ra in

dica

13M

-22～

24M

-7～

9E9

6°13

'46.

, N21

°54'

32.

88+

++

+C

itrus

max

ima

, Dim

ocar

pus l

onga

n,

Hyl

ocer

eus u

ndat

us, M

angi

fera

indi

ca14

-S-

1～2

E96°

54'3

0., N

20°5

1'35

.96

3+

+M

angi

fera

indi

ca15

-S-

3～4

E96°

54'4

6., N

20°5

1'39

.92

4+

++

+M

angi

fera

indi

ca, C

apsi

cum

frut

esce

ns, P

hase

olus

vul

gari

s16

-S-

5～6

E96°

56'3

0., N

20°5

0'15

.90

0+

++

+M

angi

fera

indi

ca17

-S-

7～8

E96°

59'1

7., N

20°4

7'36

.97

8+

++

++

Man

gife

ra in

dica

18-

S-11～

12E9

6°59

'39.

, N20

°44'

45.

983

++

++

Man

gife

ra in

dica

19-

S-13～

14E9

6°59

'53.

, N20

°44'

04.

1008

++

+M

angi

fera

indi

ca20

-S-

15～

16E9

6°57

'19.

, N20

°39'

42.

905

++

++

Man

gife

ra in

dica

B. cucurbitae

Vag

etat

ion

EN

yaun

g Sh

we

Tow

nshi

p(N

yaun

g Sh

we,

Sha

n st

ate)

MA

SL

BPe

gu T

owns

hip

(Bag

o R

egio

n)

C

Sint

gain

g To

wns

hip

(Man

dala

y R

egio

n)

Path

eing

yi T

owns

hip

(Man

dala

y R

egio

n)

D

Kal

aw T

owns

hip

(Tau

nggy

i, Sh

an st

ate)

Taun

ggyi

Tow

nshi

p(T

aung

gyi,

Shan

stat

e)

A

B. dorsalis

B. zonata

Hle

gu T

owns

hip

(Yan

gon

Reg

ion)

Are

aG

PS p

ositi

on(re

pres

enta

tive

poin

t )

B. carambolae

B. correcta

Orc

hard

No.

Trap

No.


Table 2. Number of fruit flies in each species.

B. (Bactrocera ) carambolae Methyl eugenol 6 451 37B. (Bactrocera ) correcta Methyl eugenol 2,043 13,794 1,102B. (Bactrocera ) dorsalis Methyl eugenol 1,226 50,078 1,417B. (Bactrocera ) zonata Methyl eugenol 4 182 0B. (Zeugodacus ) cucurbitae Cue-lure 152 416 0

**Fruits samplingon phase 2

Species Lurephase 1* phase 2*

Trapping

0.01

0.1

1

10

100

1000

B. carambolae

0.01

0.1

1

10

100

1000

B. dorsalis

0.01

0.1

1

10

100

1000

B. correcta

0.01

0.1

1

10

100

1000B. cucurbitae

0.01

0.1

1

10

100

1000

B. zonata

FTD

FTD

FTD

Fig 3. Seasonal FTD (Flies per trap per day) values of five Bactrocera species.

Item of horizontal axis for the township and first letter of the research area; Yangon Region (Y), Bago Region (B), Mandalay Region (M) and Shan State (S). *Data of the dry season was not available because research in Shan State, Kalaw, Taunggyi and Nyaung Shwe was carried out during the rainy season only. Solid bar and open bar indicate FTD average in phase 1 and phase 2, respectively. Vertical lines indicate the standard error.

*Phase 1 and Phase 2 were carried out from January 20 to February 21, 2014 and from May 12 to June 18, 2014, respectively. **Fruits means Mangifera indica.


on the farms (data not shown). The first species, B. carambolae,

was detected on only one orchard, and the number trapped was

extremely small. As that orchard had no difference in pesticide use

from the orchards with large numbers of detected B. correcta and

B. dorsalis, it can be said that the relative population density of B.

carambolae is low in Myanmar, or that members of the species living

in neighboring habitats occasionally come into the orchard when

climate and/or ecological conditions are favorable. It may be useful to

conduct additional surveys in surrounding fields to further clarify the

occurrence of B. carambolae.

The remaining species, B. zonata, and B. cucurbitae, were not

detected in fresh mango fruits. Various fruit trees or vegetables are

planted in or around the orchard (Table 1), and it can be said that

there are more suitable host plants than mangoes for them.

In this survey, fruit collection was conducted mainly of fallen

mango fruits, which are different in quality from the ones used

for export. The quality difference might also lead to differences in

infestation rates for different fruit fly species. Therefore, further

study of mango fruits distributed on the market may reveal possible

infestation of the three other species besides B. correcta and B.

dorsalis.

A variety of fruits and vegetables are cultivated in Myanmar. In a

series of activities done in the JICA project, other Bactrocera species

were also trapped, which infested various fruits and vegetables apart

from mangoes. The findings for those species will be introduced on

another occasion with identification and classification results. Since

there is no detailed information for the distribution of important

agricultural fruit fly pests such as B. correcta, B. cucurbitae and B.

dorsalis, it is insufficient to consider targets for plant quarantine

treatments in the trading of fruit and vegetable commodities.

In this paper, basic information was presented on the status of

fruit fly species in major mango production sites of Myanmar,

which should help Myanmar and its trade partners consider proper

management and development of disinfection methods, as well as

quarantine regulations and requirements.

In addition, as originally aimed for in the JICA project, this

survey was conducted in cooperation with local staff, improving

their technical skills in fruit fly identification; therefore, the outcome

should be evaluated also from the viewpoint of technical cooperation

in phytosanitary quarantine.

Acknowledgements

We would like to thank the JICA, specifically the Rural

Development Department and the JICA Myanmar Office, for

supporting the activities for this study. Also, we thank the Government

of Myanmar, particularly the Plant Protection Division (PPD) of

the Ministry of Agriculture, Livestock and Irrigation (MOALI)

and the Plant Protection Division of the Ministry of Agriculture,

Forestry and Fisheries (MAFF) of Japan for various arrangements

necessary for the research work. For all assistance on site, we would

like to thank Mrs. Tar Nway Oo, Ms. Thee Su Su Aung, Ms. Tinzar

Hla Oo, Mr. Zayar Yar Soe (PPD, Yangon) and other members of

PPD regional offices. The staff of the Naha Plant Protection Station

technically helped with the trapping work. The staff of the Nagoya

Plant Protection Station helped with the identification of fruit flies.

Particular appreciation is given to Dr. K. Tsuruta for his advice on

fruit fly identification, and to Mr. I. Miyazaki (Naha Plant Protection

Station) for his technical advice in various aspects of the survey. We

are grateful to Mr. Y. Yokoi (Yokohama Plant Protection Station) and

Mr. M. Kaneda, (Yokohama Plant Protection Station) who reviewed

drafts and provided critical comments.

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和　文　摘　要

ミャンマーのマンゴウ栽培園地におけるミバエ発生調査

中原　重仁 , Mu Mu Thein 1), Khin Nyunt Yee 1), Shaine Shane Naing 1),

Win Soe 2), Than Htiek2) , 片山　満 3)

横浜植物防疫所調査研究部

　2014年 1-2月（乾期）及び同年 5-6月（雨期；マンゴウの収穫期）にミャンマーの主要なマンゴウ生産地域であるヤンゴン、バゴー、マンダレー、そしてシャン州南部の 20のマンゴウ生産園地でミバエ類の発生調査を実施した。5-6月に果樹園内からミバエ幼虫の寄生したマンゴウの落果を回収し保管調査を行った結果、B. carambolae、B. correcta、B. dorsalisの 3種が羽化した。特に B. correcta及び B. dorsalisの 2種が調査した園地の 8割以上の園地のマンゴウで確認された。これに対し B.

carambolaeはバゴーの 1園地で採取したマンゴウで寄生が確認されたものの発見頭数は 37頭のみであり、同園地における前 2種の発見頭数に比べて極めて少なかった。さらに、マンゴウの害虫として様々な文献上に報告のある B. cucurbitaeと B.

zonataについては今回果実調査では確認されなかった。また、メチルオイゲノールとキュウルアの 2種類の誘引剤を用いたトラップのべ 172個を設置して調査した結果、B. carambolae、B.

correcta、dorsalis、B. zonata及び B. cucurbitaeが誘殺された。B. correctaと B. dorsalisの誘殺頭数は他種に比べて極めて多く、1トラップあたり 1日あたりの誘殺虫数（FTD）は両種とも5-6月のマンダレーでの調査で最高値を示し、B. correctaでは54.4、B. dorsalisは 241であった。他の B. carambolae、B. zona-

ta及び B. cucurbitaeの最高値はそれぞれ 3.1、1.2、3.0であった。これらの結果から、調査したマンゴウ園地では B. correcta 及びB. dorsalisの発生量が圧倒的に多く、この 2種がマンゴウの主要害虫であると考えられた。一方 B. carambolae、B. zonata、B.

cucurbitaeはマンゴウ果実への寄生率が極めて低いか全くなく、トラップによる誘殺頭数も少なかった。この要因としては、これら 3種のミャンマー国内でのそもそもの分布密度が低いか、あるいはマンゴウ園地の周辺に生息し、環境要因や好適寄主植物のフェノロジー等の条件により一部がマンゴウ園地に侵入する可能性等が考えられた。

───────────────────────────────────────────────────────────1) Plant Protection Division (PPD), Yangon2) Plant Protection, Department of Agriculture, Ayeyarwaddy Resion3)元神戸植物防疫所大阪支所（福岡市）

field survey on fruit flies (diptera: tephritidae) in …...62 res. bull. pl. prot. japan no.54...

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