International Journal of Scientific & Engineering Research, Volume 5, Issue 3, March-2014 961

ISSN 2229-5518

Study on Population Abundance of Papaya Mealybug (Paracoccus marginatus Williams & Granara de Willink) in the North Minahasa

Regency of North Sulawesi Province, Indonesia

William Tairas, Max Tulung, Jantje Pelealu, S.J. Rondonuwu

Abstract— We have conducted a research to study on population and the level of attacks by mealybug (Paracoccus marginatus), which damages the papaya plant, in three villages of papaya production centers, namely Dimembe Village, Matungkas and Paslaten in North Minahasa Regency, North Sulawesi Province, and to assess the abundance of populations of P. marginatus in the dry season and the rainy season. The samples were taken once in June 2011. Observations on population and attack by P. marginatus in the two seasons were made at intervals of one month, starting in April to December 2011 in Dimembe Village where the population of P. marginatus was highest.

The results showed that the abundance of populations of P. marginatus was found in Dimembe Village (2,509 ± 1,732 individuals/plant), followed by Matungkas Village (1018 ± 745 individuals/tamaman) and Paslaten Village (421 ± 419 people/plant). The level of attack on the leaves in Dimembe, Matungkas, and Paslaten Villages were (48 ± 13) %, (25 ± 10) %, and (11 ± 7) %, respectively; while the level of attacks on fruits in Dimembe, Matungkas and Paslaten Villages were (32 ± 19) %, (9 ± 7) % and (7 ± 6) %, respectively. Population abundance of P. marginatus in dry season was 3226 individuals/plant which was higher than in the rainy season, which counted 285 individuals/plant. The total population of P. marginatus was positively correlated with the level of attack on the fruit and leaves of papaya plants. In the dry season the attack level on the fruits was 32% and 49% on the leaves; while during the rainy season the attack level was

11% on fruits and 15% on leaves.

Index Terms— P. marginatus, mealybug, papaya, abundance population, attack level, North Minahasa, North Sulawesi.

——————————  ——————————

1 INTRODUCTION

APAYA mealybug (Paracoccus marginatus) is a destructive polifag pest of tropical fruits, vegetables, and ornamental plants [1]. P. marginatus is a species originated from Mexi-
co and Central America and was first described by Williams and Granara de Willink in 1992. In 1994 P. marginatus became a pest of papaya in 14 countries in the Caribbean region, and in 1998 P. marginatus was found in the state of Florida, and in
2001 spread to the state of Illinois [2], then to India in 2007 [3].
In Indonesia P. marginatus was first found in papaya plants
at the Bogor Botanical Garden, West Java in May and July 2008
[4], and has spread to Bali and Sulawesi islands [5]. Since the
beginning of 2009 and the papaya in North Minahasa Manado has been attacked by P. marginatus [6]. Interviews with papaya farmers in February 2011 showed that P. marginatus has spread and caused damage to the leaves and fruits of papaya
in North Minahasa region. So far population abundance and damages to papaya crops caused by P. marginatus in North Minahasa Regency has not yet been reported.

————————————————

• William Tairas is a Doctoral candidate in the Postgraduate Program, Sam

Ratulangi University, Manado, North Sulawesi, Indonesia. Cell phone -

+6281356222165. E-mail: tairasw@yahoo.com

• Max Tulung, Jantje Pelealu, and S.J. Rondonuwu are Professors of Agri-

cultur, Faculty of Agriculture, Sam Ratulangi University, Manado, North

Sulawesi, Indonesia.

Population abundance is the number of individuals per unit area/plant where the number of organisms in a popula- tion changes over time as a result of various factors such as birth, death, immigration, and emigration [7], [8]. Abundance of insect populations is also governed by the availability of food resources [9]. Abundance and spread of pest populations in crops is very important to study to reveal various things about ecology. Therefore, a quantitative study on population growth of mealybug (P. marginatus) and percentage of attacks need to be carried out, especially when the epidemic. This in- formation is needed to provide the basis for developing a technique that effectively controls P. marginatus. Our research was aimed to study the population abundance and attack rates by P. marginatus in several papaya production centers, and to analyse P. marginatus population abundance in the dry and the rainy seasons in papaya plants in North Minahasa Regency.

2 MATERIALS AND METHODS

Sampling and observation of the abundance of P. marginatus were conducted in three temperate tropical papaya producer villages in North Minahasa District, North Sulawesi Province, Indonesia. They are Dimembe Village (01º 30' 29.3" N and 124º
58' 45.0" E), Matungkas Village (01º 28' 12.2" N and 124º 57'
54.8" E), and Paslaten Village (01º 24' 19.2" N and 125º 00' 10.7"
E). Geographically, the Matungkas village is situated on about
270 m above sea level (asl) and the Dimembe village on 219 m
asl in District of Dimembe, and the Paslaten village seats 274
m asl located in District of Kauditan North Minahasa Regency,

International Journal of Scientific & Engineering Research, Volume 5, Issue 3, March-2014 962

ISSN 2229-5518

North Sulawesi Province.
In our research we studied the mealybug population abun-
dance on the leaves and fruit of papaya plants in the three vil-
lages,) calculated the rate of leaf attack by P. marginatus in the
three villages, and analysed the differences in population
abundance of P. marginatus in the dry season and the rainy
season in the village with the highest population.
Observations were made in the plantations under attacked
by P. marginatus. Papaya plants were cultivated monoculture-
ly. Observation plots were made by dividing the plantation
area of 5000 m2 into five plots. Four samples of papaya plant
were taken from each plot by purposive sampling. P. margina-

tus invested papaya leaves and fruits were taken and put into

plastic bags. Population abundance of P. marginatus was
measured by counting the number of egg and nymph groups
under a stereo microscope.
Percentage of P. marginatus on the fruits and leaves was cal-
culated by dividing the number of fruits/leaves attacked by
the total number of fruits/leaves in each plant individual by
(1);

ulations of the insect due to changes in physiology develop- ment, migration and dispersal, resulting in a local population explosion [10]. Variations in temperature and humidity in the crop environment (microclimate) occur due to variations in crop conditions are a result of agronomic practices in the cul- tivation of plants, plant population and fertilization.

Fig. 1. The population of egg and nymph groups of P. margina- tus on papaya crop in the three villages of study.

P = n × 100%

(1)
with P = percentage attack rate, n = number of fruits/leaves infected per plant, and N = total number of fruits/leaves per plant.
Population abundance of the papaya mealybug (P. margina- tus) in two different seasons, i.e. the dry season and the rainy season, was calculated every month, from April to December
2011. The results were analyzed using the analysis of variance (ANOVA). If the analysis results indicated that the effect was significance, then further tests were conducted by using the Tukey method at the level of 95%.

3 RESULTS AND DISCUSSION

3.1 Population Comparison of P. marginatus Egg and

Nymph Groups in Three Villages

Population of egg and nymph groups of P. marginatus di- versed in all villages. Results of Anova showed that the popu- lation number of egg and nymph groups in three studied vil- lages were significantly different (P ≤ 0.00) (see Fig. 1).
We found the highest population of eggs and nymphs in
Dimembe village (2,509 ± 1,732 individuals/plant and 823 ±
600 groups of eggs/plant), whereas in Paslaten village gave
the lowest population, although not significantly different
from the population in the Matungkas village. The differences
in nymph and egg populations of P. marginatus on papaya
crops in the three villages were thought to be influenced by
differences in climatic factors, plant cultivation method and
the presence of natural predators, parasitoids and pathogens.
Spacing of the papaya plants in Dimembe village varied from
2 to 3 meters, which was suspected to causing the easier
spread of P. marginatus onto other papaya plants. One of the
characteristics of P. marginatus is its first and second instars
both have high activity and continuesly migrate to another
niche for survival. Temperature and humidity also affect pop-
The high plant populations and the dense spacing allow the plants to grow very densely, resulting in microclimate in the plantation with a consequence of high susceptibility to herbi- fora infestation [11]. Papaya cultivation in Paslaten village is almost the same as in Dimembe village, yet mealybug Aleo- rodicus dispersus outnumbered P. marginatus. Low popula- tions of P. marginatus in Paslaten village might be resulted from competition in one habitat and the presence of its natural enemies [12].

3.2 Attack Percentage of P. marginatus in the Three

Villages

Results of the Anova analysis showed differences in presentage levels of mealybug attack on fruits and leaves in the three study areas (P ≤ 0.00). The results showed that the average percentage rate of mealybug attack on the fruits and leaves in Dimembe Village was significantly higher (32.01 ±
18.63) % than in Paslaten Village (7.01 ± 5.61) % and Matungkas Village (9.52 ± 6.61) % (see Fig. 2). Similar condi- tions also occured where mealybug attack on the leaves was highest in Dimembe Village (48.07 ± 12.87) %. The level of at- tack in the Matungkas Village was (24.85 ± 10.26) % and Paslaten Village was (10.75 ± 7.25) %.
Population growth led to an increase in the percentage level of attack on the papaya fruits and leaves in all villages of pa- paya production centers. This suggests that if the population abundance of P. marginatus were low, the percentage of attack will itself be reduced, and vice versa. In general, this insect has a high adaptability to environmental conditions of their life. Deployment and density of the population are closely related to local conditions, such as altitude [13] and climatic factors (temperature, humidity, rainfall, light) and biotic factors [9], [14].

International Journal of Scientific & Engineering Research, Volume 5, Issue 3, March-2014 963

ISSN 2229-5518

Fig. 2. Percentage of P. marginatus pest attack on papaya fruits and leaves in the three villages of study. n = 20 ± SD. Figures followed by different letters indicate significantly different.

Fig. 3. Fluctuations of P. marginatus mealybug populations on papaya plants and total rainfall observation in April-December

2011.

3.3 Population Abundance P. marginatus in Dry and

Rainy Seasons

Observations on abundance of population of P. marginatus in the dry season and the rainy season were carried in Dimembe Village as the village showed the highest mealybug popula- tion. The results showed that from April to September the to- tal population significantly growed from 30 individuals/plant in April up to 3,183 individuals/plant in September (Fig. 3) and dropped after then in October-December. This was inline with the condition of rainfall. Changes in population abun- dance indicate a close relationship between the amount of rainfall and the growth of mealybug populations, where the highest population coincides with dry season [15].
Variation in population abundance of eggs also relates with changes in population of nymphs. When the nymph popula- tion increases, so does the egg number; and vice versa. The population of P. marginatus reached an average of 3,226 indi- viduals per plant in August when the total rainfall touched
188.5 mm (Fig. 3). Such condition indicates a tight relationship between the population growth rate with the surrounding environment as explained by Painter [16] and Chapman [17]. Mealybug take approximately 2 to 3 months to grow properly when climatic conditions support, such as low rainfall, and food is plenty. In contrast, when the climatic conditions are not suitable, e.g. in rainy season, the mealybug populations decline. Our findings showed a 563.5 mm rainfall and 28-day raining yields a declined population by an average of 285 in- dividuals per plant. The high population in the dry season is a common phenomenon that has long been known on tropical insects [18]).
The influence of temperature on the development of insects closely relates to humidity as it could influence the growth and insect activity. During our observation in July to Septem- ber the average temperature was 32 ºC and humidity average of 53.33%, which was an ideal condition for the development of mealybug [15].
The influence of temperature on the development of insects closely relates to humidity as it could influence the growth and insect activity. During our observation in July to Septem- ber the average temperature was 32 ºC and humidity average of 53.33%, which was an ideal condition for the development of mealybug [15].

4 CONCLUSION

Papaya mealybug P. marginatus has spread in three villages of papaya producers in North Minahasa Regency, North Sulawe- si Province. Of the three villages observed, Dimembe Village had the highest population abundance (2,509 ± 1,732 individu- als/plant), which was associated with a high rate of attacks on leaves (48.07 ± 12.87) % and the fruits (32.01 ± 18.63)%. Popula- tion abundance of P. marginatus on papaya plants showed dif- ferences in two different seasons. The population was higher in the dry season (an average 3,226 individuals/plant) and lower in the rainy season (an average 285 individuals/plant).
Our study did not take into account the presence of natural enemies of P. marginatus. Therefore, it is important to study the population conditions by looking at the influence of the natural enemies.

REFERENCES

[1] D. R. Miller and G. L. Miller, "Redescription of Paracoccus margina- tus Williams and Granara de Willink (Hemiptera: Coccoidea: Pseu- dococcidae), including descriptions of the immature stages and adult male," Proceedings of the Entomological Society of Washing- ton, vol. 104, pp. 1-23, 2002.

[2] A. Walker, M. Hoy, and D. Meyerdirk, "Papaya Mealybug, Para- coccus marginatus Williams and Granara de Willink (Insecta: He- miptera: Pseudococcidae)," The Entomology and Nematology De- partment, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, USA. 2003.

[3] R. K. Tanwar, P. Jeyakumar, and S. Vennila, Papaya mealybug and its management strategies. New Delhi: National Centre for Integrat-

ed Pest Management, 2010.

International Journal of Scientific & Engineering Research, Volume 5, Issue 3, March-2014 964

ISSN 2229-5518

[4] R. Muniappan, "Papaya mealybug, a new invader in Asia," IAPPS Newsletter, vol. No. 1, 2009.

[5] R. Muniappan, "Recent invasive hemipterans and their biological control in Asia," in 5th Meeting of the Asian Cotton Research & De- velopment Network, 23-25 February 2011, Lahore, 2011.

[6] D. T. Sembel and W. Moniaga, "Survey Hama Baru Paracoccus mar- ginatus William and Granara de Willink (Homoptera; Pseudococ- cidae) pada Tanaman Pepaya di Sulawesi Utara," Eugenia: Media Publikasi Ilmiah Pertanian, Fakultas Pertanian Universitas Sam Rat- ulangi, vol. 15 2009.

[7] R. F. Norris, E. P. C. Chen, and M. Kogan, Concept in Integrated

Pest Management. New Jersey, USA: Prentice Hall, 2003.

[8] R. C. Tarumingkeng, Dinamika Populasi Kajian Ekologi Kunatitatif.

Jakarta: Pustaka Sinar Harapan dan Universitas Kristen Krdida

Wacana, 1994.

[9] D. J. Borror and D. M. DeLong, An Introduction to the Study of

Insects. New York: Rinehart, 1954.

[10] A. P. Gutierrez, D. E. Havenstein, H. A. Nix, and P. A. Moore, "The Ecology of Aphis craccivora Koch and Subterranean Clover Stunt Virus in South-East Australia. II. A Model of Cowpea Aphid Popu- lations in Temperate Pastures," Journal of Applied Ecology, vol. 11, pp. 1-20, 04/01 1974.

[11] Nurindah, "Pengelolaan Agroekosistem dalam Pengendalian Ha- ma," Indonesian Tobacco and Fibre Crops Research Institute, Ma- lang, Indonesia. 2006.

[12] M. A. Altieri, "The ecological role of biodiversity in agroecosys- tems," Agriculture, Ecosystems & Environment, vol. 74, pp. 19-31,

1999.

[13] J. F. Brown, A. Kerr, F. G. Morgan, and I. H. Parbeny, A course

Manual in Plant Protection. Melbourne: Hedges and Bell Pty. Ltd.,

1980.

[14] S. Sastrodihardjo, Pengatar Entomologi Terapan. Bandung: ITB Press, 1984.

[15] J. M. E. Mamahit, Kelimpahan Populasi,Biologi dan Pengendalian Kutu Putih Nenas Dysmicoccus brevipes (Cockerell)(Hemiptera: Psedococcidae) di Kecamatan Jalancagak, Kabupaten Subang. Dis- ertasi Doktoral Thesis. Sekolah Pasca Sarjana, IPB. Bogor. 2009.

[16] R. H. Painter, Insect Resistence in Crop Plants. New York: MacMil- lan, 1951.

[17] R. F. Chapman, The Insect Structure and Function. Second Edtion.

New York: Elsevier, 1971.

[18] A. Rauf, "Dinamika Populasi Spodoptera exigua (HUBNER) (Lepi- doptera: Noctuidae) pada Tanaman Bawang Merah di Dataran Rendah," Buletin Hama dan Penyakit Tumbuhan, vol. 11, pp. 39-47,

1999.