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1 Breadfruit Mealybug: Icerya aegyptiaca

1 Breadfruit Mealybug: Icerya aegyptiaca

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18 Mealybug Alikes



cies affected by this insect include Acacia

nilotica, A. tortilis, Casuarina equisetifolia,

Dodonaea viscosa, Grevillea robusta, Morus

alba and Mangifera indica (Sundararaj and

Muthukrishnan 2008).



18.3



Perissopneumon ferox



Perissopneumon ferox Newstead is also similar to

mealybug in appearance. Rodolia fumida and

Leptus sp. were recorded from Malihabad (Singh

1993). Perissopneumon ferox was reported as a

new

mealybug,

Perissopneumon

ferox

(Margarodidae, Homoptera), on mangoes from

Uttar Pradesh, India. Heavy infestation of the

pseudococcid P. ferox on mango was seen in

Uttar Pradesh, India. Two predators, the coccinellid Rodolia fumida and the Erythraeid Leptus

sp., were seen preying on P. ferox (Srivastava and

Verghese 1985). Perissopneumon tamarindus

Green was also reported as a mealybug on ber

and other crops in India (Butani 1973).



18.4



Drosicha spp.



Drosicha stebbingi Green and Drosicha mangiferae are popularly called mango mealybugs

besides Perissopneumon ferox. Mealybug alikes,

Drosicha mangiferae (Green) and Drosicha dalbergiae Green was recorded as mealybugs on

pomegranate and papaya in India. Mealybug

alikes, Drosicha stebbingi Green, D. mangiferae

(Green) (Pruthi and Batra 1960), Drosichiella

tamarindus Green and Perissopneumon tamarindus Green (Butani 1973) were reported as

mealybugs on ber in India. Drosicha stebbingii

Green on forest plants is reported as a mealy

bug occurring throughout the sal (Shorea

robusta) forests of north India. It was also

quoted as mealybug on Tectona grandis and

Albizia spp. in India (Joshi 1992). Drosicha

mangifera was also recorded as a mealybug pest

on black nightshade (Solanum nigrum L) and

Indian gooseberry (Phyllanthus emblica) from

Uttar Pradesh, India.



233



Incidence of Drosicha mangiferae on ashwagandha was reported as mealybug infestation in Jammu and Kashmir, India. The pinkish

nymphs and female adults suck the sap from

the twigs, leaf stock and also along the midrib,

and the infestation was mainly concentrated

on the terminal part of the shoot. Sumnius vestita and Cryptochaetum were known to attack

D. mangiferae. In western Uttar Pradesh,

Drosicha mangiferae has one generation a

year and diapauses in the egg stage in soil for

about 7 months.

The so-called mango mealybug D. stebbingi

was predated by several coccinellids, but none of

these natural enemies were found to give adequate control of D. stebbingi (Rahman and Latiff

1944, Wadi and Batra 1964, Singh 1993).

Beauveria bassiana was found infecting nymphs

of Drosicha mangiferae in the field, and the

pathogen was found infecting the margarodid in

orchards in five localities in India. In field trials

on infested mango panicles, spray application of

a suspension having 4.8 × 106 conidia/ml reduced

populations of D. mangiferae by 33.3–100 % in

10 days (Srivastava and Fasih 1988).

An integrated approach involving cultural,

mechanical and chemical methods is ideal for the

management of mango mealybugs. Raking of

soil four times (May, June, August and October)

in Uttar Pradesh afforded the best control of egg

hatching of the margarodid Drosicha mangiferae;

30 % of the eggs hatched, as compared with 68 %

for no treatment (Chandra et al. 1989). Complete

control could be obtained by the use of grease

bands round the trunks from the second week of

December. An alternative method proved to be

banding with coal tar, which remains effective for

only a relatively short period (Prasad and Singh

1976). Sticky bands were found to remain effective for only a short time (up to 15 days after

application). The commonly used bands of mixture of rosin and castor oil (4:5) and coal tar and

grease (2:1) prevented the nymphs from ascending for only up to 5–6 days after application.

Field tests were carried out in Hissar, India, and

revealed that the slippery band of alkathene sheet

was most effective of all in blocking the ascend-



M. Mani and S. Gul



234



ing nymphs, as an average of 2.79 nymphs per

sample area were able to cross it every alternate

day as compared with 407.3 nymphs on untreated

trees (Lakra et al. 1979). A 30-cm-wide polyethylene band tied round the tree 50–100 cm above

the ground and with its lower edge plastered over

with mud was sufficiently slippery to prevent the

passage of Drosicha stebbingi nymphs and much

cheaper than the conventional sticky band (Bindra

and Sohi 1974). The double girdle band of alkathene was more effective as it stopped the few

nymphs of Drosicha mangiferae that managed to

cross the first band (Srivastava 1980).

Trunk sprays of quinalphos, diazinon and

methyl parathion at 0.0.75–0.15, 0.05–0.1 and

0.05–0.1 % in Haryana were highly effective

against ascending first instar nymphs that had

collected below bands. In Bihar, alkathane

banding was followed by three to four applications to the trunk of 0.04 % malathion or three

of 0.03 % dimethoate, 0.03 % phosphamidon,

0.04 % diazinon or 0.05 % thiometon during

January. All these insecticides were equally

effective when applied to the shoots (after banding of the trunks) in late February and early

March. Diazinon and thiometon were too expensive for their use to be recommended (Prasad

and Singh 1976). Field tests carried out in Delhi

indicated that diazinon was the most effective

compound and was significantly superior to

monocrotophos and chlorpyrifos, both of which,

however, gave fairly satisfactory control of the

pest (Srivastava 1980). Infested trees were

sprayed once, with acetamiprid at 100 g/100 L

of water against first instar in the second week

of February in Pakistan (Karar et al. 2009).

Against Drosicha mangiferae on guava, fenitrothion at 0.1 % was the most effective treatment,

followed by phosalone at 0.07 %, quinalphos at

0.05 %, monocrotophos at 0.04 %, parathionmethyl at 0.05 %, and bromophos-ethyl at 0.07

% and phosphamidon at 0.03 %. Phenthoate at

0.05 %, dimethoate at 0.03 % and malathion at

0.1 % were less effective (Dalaya et al. 1983).

Among 24 insecticides that were tested against

Drosicha mangiferae in Haryana, quinalphos at

0.025 % and fenitrothion, carbophenothion and

parathion-methyl, each at 0.05 %, were highly



effective against gravid females of the pest.

Spraying of acephate, methyl demeton, monocrotophos, quinalphos, dimethoate and phosphamidon at 0.08 % was able to keep the

population of mealybug D. mangiferae under

check.



18.5



Stictococcus vayssierei



Stictococcus vayssierei Richard has been reported

as root mealybug of cassava (Manihot esculenta)

in Cameroon (Ngeve 2003). The larvae and adults

attack young feeder roots of germinating cuttings, causing extensive leaf-fall, wilting, tip dieback and death of plants. Plants that escape early

infestation develop normally and tuberize, but the

mature tuberous roots are small and become covered with the root scale, making them unattractive to market. In severe infestations, a mature

tuberous root of about 40 cm long may harbour

up to 500 mealybugs. It is most severe during the

dry season in lateritic and clayey soils, in fields of

depleting fertility and in thinly prepared land

where planting has been done on the flat. The

prevalence of the pest in the semi-humid forest

region of Cameroon increased from 12.5 % in

1990 to 87.5 % in 1999. S. vayssierei infestation

was more severe (30 mealybugs/hill) when cassava was planted on the flat than when planted on

ridges (16 adults/hill). Plants also sprouted better

(91 %) when cassava was planted on ridges than

when planted on the flat (71 %). Root yields (31.4

t/ha) and root numbers (7 roots/hill) were also

higher in cassava planted on ridges than in those

grown on the flat (24.5 t/ha and 4.5 roots/hill,

respectively). For plants grown on the flat, the

improved clones suffered the least attack by S.

vayssierei, clones 8017 and 8034 showing the

most tolerance (19 and 22 females/hill, respectively) when compared with the local, Meyiboto

(49 females/hill). Stictococcus vayssierei was

more severe when cassava was intercropped;

there were 40, 48 and 59 mealybug adults per hill

when cassava was intercropped, respectively,

with maize, groundnuts or maize and groundnuts

combined. By contrast, maize suffered no yield

depression when intercropped with cassava. S.



18 Mealybug Alikes



vayssierei is a major threat to cassava production

in Cameroon and neighbouring Central African

countries. It calls for emergency integrated control measures. With poorly enforced quarantine

regulations, and the unrestricted movement of

vegetative planting stakes from one country to

the other in Africa, this pest is likely to become

an epidemic if strong measures are not taken to

control its spread. The effects of season, rainfall

distribution and soil type on oviposition and

insect development need to be further studied so

as to determine whether it is the physical or

chemical properties of the soil that play such differential role in pest prevalence and severity.

Finally, the mechanism of cultivar tolerance to

pest infestation could be studied to throw light on

plant traits and cultural conditions that could be

exploited in screening cassava clones for yield

and pest tolerance. Such studies could lead to the

early release of improved, mealybug-resistant

varieties to growers. Orientations for future

research are discussed. Monocropping is recommended in areas where pest impact is very severe.

Also, disinfestation of cuttings with insecticidal

bioproducts should be exploited to reduce pest

impact. Finally, rhizosphere biocontrol agents

such as endomycorrhizae should be studied to

determine their usefulness in controlling the pest

under farming conditions in Cameroon (Ngeve

2003).



18.6



Pseudaspidoproctus fulleri



Pseudaspidoproctus

fulleri

(Homoptera:

Margarodidae), has been reported as mealybug

in Mauritius. Cynodon dactylon was found to

be the preferred food plant of the pest.

Destruction of the plant where it grows as a

weed with herbicides is suggested as a method

of controlling the pest. The predator Rodolia

chermesina was observed consuming large

numbers of the pest, and the parasitoid

Cryptochetum monophlebi is also mentioned as

a potential biological control agent (Rajabalee

and Banymadhub 1990).



235



18.7



Drosicha dalbergiae



Drosicha dalbergiae (Stebbing) has been reported

as almond mealybug in Kashmir, India (Malik

et al. 1972). The eggs are laid in clusters and covered with cottony ovisacs, exhibiting silky touch

and appearance. The freshly laid eggs are yellowish in colour and oval shaped, which later on

turns brownish in colour during hatching. The

adult female of D. Dalbergiae is brownish grey in

colour, devoid of wings, sluggish and similar in

shape as it is in last nymphal instar. Its body is

covered with ash white mealy powder with three

pairs of small black legs. However, males are

more active and smaller in size with a pair of

wings. The pest passes through one complete

generation in a year.

The pest feeds on both aerial and underground

parts of almond plants, colonizing in the collar

region of the tree in crevices and at wounded sites

(Masoodi et al. 1988). On migration to the aerial

parts of the plant, the pest feeds on the plant

phloem and excrete honeydew that cover the

leaves, trunk and fruits, thus making the fruit

unmarketable due to development of black sooty

mould and sickly appearance.

The management strategy involves with

• Raking of the soil around the base of the

infested trees so that egg masses get exposed

to the sun and get killed.

• Application of sticky bands around the tree

trunk so as to check the nymphs from crawling

up the trees (four parts of castor oil and five

parts of resin) 0.5–1 m above the ground level

during the month of May. It will remain effective for a period of 2 weeks after which it

should be repeated.

• The soil application of carbaryl (10 % dust)

will keep the mealybug population under

check.

• Insecticidal spray of methyl-o-demeton

(0.02 %) will exhibit maximum mortality of

almond mealybug.

• The combined effect of carbaryl (10 % dust)

and dimethoate (0.03 %) applied as soil drench



236



and foliar spray, respectively, plays a significant role in suppression of the pest (Shaheen

et al. 2014).



References

Bhatnagar VS, Jadhav DP, Pawar CS (1984) Parasitoids of

pigeonpea mealy bug, Ceroplastades cajani Mask. Int

Pigeonpea Newslett 3:45

Bindra OS, Sohi BS (1974) A note on control of the

mango mealybug in the Punjab. Indian J Hortic

31:102–103

Butani DK (1973) Insect pests of fruit crops and their control. Pesticides 7:33–35

Chandra A, Bhati DPS, Singh KM (1989) Note on the

effect of soil raking and irrigation on survival and

hatching of eggs of mango mealy bug, Drosicha mangiferae Green. Curr Agric 13(1–2):103–104

Dalaya VP, Rajput SG, Mali AR, Mohite PB (1983)

Comparative efficacy of insecticides against guava

mealy bug Green. Indian J Plant Protect

11(1/2):138–139

Dantsig EM (1979) A new peculiar genus of mealybugs

(Homoptera, Coccoidea, Eriococcidae) from the

European part of the USSR [Russian]. Trudy

Vsesoyuznogo Entomologicheskogo Obshchestva

61:46–47

Joshi KC (1992) Handbook of forest, zoology & entomology. Oriental Enterprise, Dehradun, 383p

Karar H, Arif MJ, Sayyed HA, Saeed S, Abbas G, Arshad

M (2009) Integrated pest management of mango

mealybug (Drosicha mangiferae) in mango orchards.

Int J Agric Biol 11:81–84

Lakra RK, Kharub WS, Singh Z, Lakra RK, Kharub WS,

Singh Z (1979) Comparative efficacy of some banding

materials against mango mealybug, Drosicha mangiferae Green. in Haryana. Indian J Entomol

41(2):170–176

Malik RA, Punjabi AA, Bhat AA (1972) Survey study of

insect and non insect pests in Kashmir. Horticulture

3:29–44

Masoodi MA, Bhagat KC, Koul VK (1988) Drosicha dalbergiae Green (Coccidae: Homoptera) a new pest of

almond in India. Ann Biol 4:1–2

Ngeve JM (2003) The cassava root mealybug (Stictococcus

vayssierei Richard) (Homoptera: Stictococcidae): a

threat to cassava production and utilization in

Cameroon. Int J Pest Manag 49(4):327–333



M. Mani and S. Gul

Prasad VG, Singh RK (1976) Prevalence and control of

mango mealy bug Drosicha stebbingi (Green) in

Bihar. Indian J Entomol 38(3):214–224

Pruthi HS, Batra HN (1960) Some important fruit pests of

North West India, Indian Coucil Agricultural Rearch

(ICAR) Bull No. 80, New Delhi 113 p

Rahman KA, Latiff AM (1944) Description, bionomics and

control of the giant mealybug Drosicha stebbingi

(Homoptera, Coccidae). Bull Entomol Res 35:197–209

Rajabalee A, Banymadhub N (1990) Preliminary notes on

the mealybug Pseudaspidoproctus fulleri Cockerell

(Homoptera: Margarodidae), a new introduction to the

Island of Mauritius [French]. Revue Agricole et

Sucriere de l’Ile Maurice 69(1–3):60–61

Rao VP (1950) Iceryine scale insects recorded from the

orient. Indian J Entomol 12:39–66

Shaheen G, Zahoor B, Ahmad AS (2014) Management of

almond mealy bug, Drosicha dalbergiae Stebbing by

chemical intervention. Ann Plant Protect Sci 22(1):22–26

Singh SP (1993) Biological control of pests. In: Chadha KL,

Pareek OP (eds) Advances in horticulture III. Malhotra

Publishing House, New Delhi, pp 1591–1616

Srivastava RP (1980) Efficacy of alkathene bands to prevent ascent of mango mealybug nymphs on mango

trees. Indian J Entomol 42(1):122–129

Srivastava RP, Fasih M (1988) Natural occurrence of

Beauveria bassiana, an entomogenous fungus on

mango mealybug, Drosicha mangiferae Green. Indian

J Plant Pathol 6(1):8–10

Srivastava RP, Verghese A (1985) Record of a new mealybug, Perissopneumon ferox Newstead (Margarodidae:

Homoptera) on mango from Uttar Pradesh, India.

Entomon 10(2):184

Sundararaj R, Karibasavara LR, Sharma G, Muthukrishnan

R (2006) Scales and mealybugs (Coccoidea:

Hemiptera) infesting Sandal (Santalum album Linn.).

Entomon 31(3):239–241

Sundararaj R, Muthukrishnan R (2008) Sucking pest

complexes of sandal and their host range in South

India. In: Gairola S, Rathore TS, Joshi G, Arun Kumar

AN, Aggarwal P (eds) Proceedings of the national

seminar on “conservation, improvement, cultivation

and management of sandal (Santalum album L.).

Brilliant Printers, Bangalore, pp 111–120

Wadi SR, Batra HN (1964) Pests of tropical and subtropical fruit trees. Entomological society of India, New

Delhi, pp 464–466

Waterhouse DF (1991) Possibilities for the biological

control of the breadfruit mealybug, Icerya aegyptiaca,

on Pacific Atolls. Micronesica (Suppl. 3):117–122

Williams DJ (2004) Mealybugs of southern Asia. The

Natural History Museum/Southdene Sdn. Bhd,

London/Kuala Lumpur, 896 p



Part II

Management of Mealybugs in Agricultural

and Horticultural Crops



19



Rice

Gururaj Katti



19.1



Mealybug Species



Mealybugs are injurious to rice in several countries. Among the species, Brevennia rehi

(Lindinger) is widely distributed across the world

in South and South East Asia, North America and

Australasia (Table 19.1). In a recent report also,

the rice mealybug has been listed as one of the

important pests of rice in Bangladesh (Ahmad

et al. 2011). It is found to cause heavy loss to the

growers in India and Pakistan. Identification of



rice mealybug species Brevennia rehi has undergone several modifications across space and time

(CABI 2003). At first, the rice mealybug

Brevennia rehi was recorded as Ripersia sacchari

Green by Lefroy (1908), attacking rice in India,

and later, Brevennia rehi was confirmed as the

valid name for the rice mealybug by Miller (1975).

It has become a primary pest in Bihar, and also in

other rice-growing states such as West Bengal,

Orissa, Bihar, Andhra Pradesh, Tamil Nadu,

Karnataka, Kerala and Maharashtra (CIE 1979).



Brevennia rehi (Photo credit: Lyle Buss, University of Florida)



19.2



Damage



Both the adults and nymphs are found in sedentary colonies and suck sap from stems and leaf

G. Katti (*)

Indian Institute of Rice Research, Rajendranagar,

Hyderabad 500030, Telangana State, India

e-mail: gururajkatti@yahoo.com



sheaths, resulting in yellowish curled leaves,

stunting and wilting of rice plant. The mealybug

populations can be easily noticed in the field as

they are covered by a distinct waxy and powdery

coating. Also, ants frequent the mealybuginfested plants, and sometimes carry the mealybugs to healthy plants. The insect pest attacks

rice during the tillering and stem elongation



© Springer India 2016

M. Mani, C. Shivaraju (eds.), Mealybugs and their Management in Agricultural

and Horticultural crops, DOI 10.1007/978-81-322-2677-2_19



239



240



G. Katti



Table 19.1 List of mealybug species recorded on rice in different regions of the world

Species

Brevennia rehi (Lindinger)

Syns: Heterococcus rehi (Lindinger);

Heterococcus tuttlei Miller and

McKenzie; Rhizoecus cynodontis

Bodenheimer; Brevennia femoralis

Borchsenius



Chlorozococcus mireorum Matile

Ferren

Chorizococcus ilu Williams

Dysmicoccus boninsis (Kuwana)



Dysmicoccus brevipes (Cockerell)

Dysmicoccus oryzae (Wijati)

Formicoccus lingnani (Ferris)

Geococcus oryzae (Kuwana)

Nipaecoccus graminis (Maskell)

Novaniliacoccus oryzae Ghosh &

Ghise

Paracoccus ilu (Williams)

Planococcoides lingnani (Ferris)

Planococcus minor (Maskell)

Pseudococcus saccharicola Takahashi



Pseudorhodania oryzae Tang

Saccaharicoccus sacchari (Cockrell)

Trionymus ceres Williams



Country/Region

Israel, Iraq, Azerbaijan, Tajikistan

and Brazil

Bangladesh

Nepal

Taiwan

Australia and Papua New Guinea

India



Bangladesh, Pakistan and

Philippines

USA

Cameroon



Reference

Ben-Dov (2008)

Alam et al.(1979), Alam and

Bhuiyan (1964)

Pradhan (1981)

Liu and Tao (1988)

Williams et al. (1981)

Narayan and Ram (1985), Radja

(1985), Velusamy and Babu

(1986), Gopalan et al. (1987a),

Ghode and Mishra(1988),

Lakshmanan et al. (1988),

Raguraman et al. (1991), Jayarani

and Velusamy (1994)

Williams (2004)

Miller and McKenzie (1970)

Ben-Dov (1994)





Bangladesh

Taiwan and China

USA

Bangladesh



Java

Bangladesh

Malaysia and Thailand



Bangladesh



Bangladesh

India



Williams (1970)

Alam and Karim (1981)

Liu and Tao (1988)

Miller and McKenzie (1970)

Alam and Karim (1981)

Williams (1970)

Williams (2004)

Alam and Karim (1981)

Williams (2004)

Williams (1970)

Alam and Karim (1981)

Williams (1970)

Alam and Karim (1981)

Williams (2004)



Fiji and New Zealand

China

Bangladesh

Philippines

Australian and Oriental region

Bangladesh

Malaysia and Thailand

China



Bangladesh

India and Pakistan

Bangladesh



Ben-Dov (2008)

Ben-Dov (2008)

Alam and Karim (1981)

Williams (2004)

Ben-Dov (2008)

Pathak and Khan (1994)

Williams (2004)

Ben-Dov (2008)

Williams (1970)

Alam and Karim (1981)

Williams (1970; 2004)

Alam and Karim (1981)



19



Rice



241



stages of the rice crop. The infested plants appear

stunted and scorched. High incidence inhibits

panicle emergence, and plants may even dry.

Grains from mealybug-infested plants do not



develop properly and have a bitter taste; if present

in normal food, they spoil the flavour after being

cooked. The pest is also known to transmit the

virus known as chlorotic streak (Williams 2004).



Damage by Brevennia rehi



19.3



Factors Influencing

Incidence of Mealybugs



The prevalence of dry period, presence of grassy

weeds, well-drained soils and upland/rain-fed

environments are major factors influencing the

mealybug incidence. Increased temperature and

wind velocity and decreased relative humidity

have been reported to increase the incidence of B.

rehi (Radja 1985). Also, the pest infestation is

more severe in unirrigated and upland fields

(Mammen 1976; Pradhan 1981). The planting

dates and irrigation regimes also influenced the

incidence of rice mealybugs. Early planting and

continuous pounding of irrigation water at 5-cm

depth throughout the growing period resulted in

lower intensity of rice mealybug infestation

(Gopalan et al. 1987a). Also, type and dosage of

nitrogenous fertiliser applied affected infestation

levels: higher levels of nitrogen increased the rice

mealybug infestation, whereas the application of

raw coir pith, raw sugarcane trash and farmyard

manure reduced the infestation (Backialakshmi

1994). During the off season, rice mealybugs survive on a variety of grasses, later spreading into



the rice nurseries, which provide the main source

of infestation. The alternative hosts include

Cynodon

dactylon,

Cyperus

rotundus,

Echinochloa crus-galli, Echinochloa colona,

Panicum repens and Paspalum scrobiculatum.

The mealybug damage is found mainly confined

to upland and rain-fed environments, particularly

in fields with uneven soil surface where the plants

grow in relatively dry soil patches. It occurs in

great number during the rainy season.



19.4



Extent of Losses



The rice mealybugs cause heavy losses to crops

in Bangladesh, India, and Thailand. High density

(>100 mealybugs/hill) causes plants to wilt and

die. Despite being a traditional pest in the upland

paddy in the eastern states of Orissa and West

Bengal, there are few reports on the quantification of the extent of rice mealybug incidence or

its damage in India. Banerjee (1956) reported

incidence of mealybugs from Midnapore, Nadia,

24 Parganas, Bankura, Murshidabad and

Jalpaiguri districts of West Bengal. Satpathi et al.



G. Katti



242



(2005) reported an average damage up to 7 % in

the rice-growing areas of West Bengal. Ghode

and Mishra (1988) reported a serious outbreak of

its occurrence in Dhenkanal, Cuttack and Puri

districts of Orissa state, the affected areas being

4,000 ha, 2,780 ha and 303 ha, respectively.

Velusamy and Babu (1986) observed a severe

attack of mealybugs in an area of 100 ha of rice in

the Pudukottai district of Tamil Nadu, India. The

population of adults and nymphs was 650–750/

hill and the affected plants failed to produce panicles. Later in two villages of Tamil Nadu,

extremely severe incidence of mealybug populations was reported up to 91.1 per tiller (Nalini

et al. 2011). There was yield reduction in

extremely stunted rice plants at a population level

of 50 mealybugs/hill (Backialakshmi 1994). The

association of high mealybug incidence with the

occurrence of sheath rot disease further aggravates the yield reducing potential of this pest in

rice (Alam and Karim 1981; Lakshmanan et al.

1988; 1991). Rice mealybugs are also associated

with rice chlorotic streak viruses as the transmission studies with the bug were positive. There

have been reports of widespread and severe outbreaks of rice mealybug infestation with association of sheath blight and sheath rot diseases in

Bangladesh during the drought years of 1950,

1957, 1966, 1972 and 1979 (Alam et al. 1979).

Both traditional and improved varieties showed

infestation, and the crop losses were estimated at

30 % because of the combined effects of drought

and mealybug. Pradhan (1981) mentioned B. rehi

as a pest of rice in the Terai belt of Nepal which

included areas of Sarlahi, Bara, Parsa, Rautahat

and Dhanusha. Rice mealybug has also been

reported as tuttle mealybug-infesting Bermuda

grass (Cynodon dactylon) in USA (Ben-Dov

2012).



19.5



timely destroying of the infested plants are useful

in preventing its spread and impact.



19.6



Varietal Resistance



Traditional/local varieties and improved cultivated varieties showed low levels of resistance

(Alam et al. 1979; Heinrichs 1983). Radja (1985)

and Gopalan et al. (1987b) reported varieties

such as IET 8616, AS 89090 and IET 12798 with

low infestation after screening them under field

conditions. Mallikarjuna Rao (1987) found that

TNAU 80030, TM 1087 and CO 43 were tolerant, with the outer leaf tip turning yellowish,

despite high bug population, while TNAU 831520

and TNAU 831521 were found to be resistant and

moderately resistant, respectively. Further studies identified more resistant sources such as Ptb

33, IR 56 and IR 58, Tending, Badal 2, Rathu

Heenati, Ptb 21, Sufaida 172, IR 42 and IR 72,

Senawee, Sufaida 172, DR 52 and ARC 575

(Jayarani 1992: Jayarani and Velusamy 1994:

Backialakshmi 1994). The studies on resistance

mechanism indicated that feeding by rice mealybug resulted in a marginal increase in total phenolic content and a large increase in total sugars,

reducing sugars, non-reducing sugars, isoleucine

and proline content of the rice plants (Gopalan

et al. 1987c). Resistant varieties had low total

nitrogen, low potassium and high calcium contents compared with the moderately resistant and

susceptible varieties (Mallikarjuna Rao 1987).

Antixenosis and antibiosis were also reported,

resulting in low oviposition and egg hatchability,

slow nymphal development, reduced adult longevity and low fecundity. Steam distillate extracts

of resistant varieties adversely affected the ovipositional behaviour and were toxic to crawlers

(Lakshmanan and Velusamy 1991).



Management

19.7



It is difficult to control B. rehi because of its protective waxy covering over its entire body and a

secure position in between the stalks and leaf

sheath; however, early detection of the infestation in the nursery as well as pulling out and



Cultural Control



Removal of alternative hosts in the vicinity of the

field is recommended to prevent pest multiplication (Ayyar 1939). It is also advised to infested

plants at the post-panicle initiation stage, burying



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1 Breadfruit Mealybug: Icerya aegyptiaca

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