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16 Dysmicoccus dennoi & Trionymus clandestinus

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66 Forage Crops and Grasses



cards can be used to trap the flying adult males,

preventing them from mating. Insecticidal soaps

and horticultural oils work great in controlling

the mealybugs. The tricky part is mealybugs tend

to hide very well where leaves attach to the stem,

so make sure you get coverage there. Horticultural

soaps and oils don’t have systemic properties,

which means when spraying, the product must

come in contact with the pest. Burn leaves with

horticultural soaps and oils. These products need

to be applied when the air temperature is cool.

Make sure your plants were watered well the day

before applying any control measures. Following

labelled rates also reduces the risk of leaf damage. More is not better. Also, make sure beneficial insects are not affected while spraying

insecticides. There are a few beneficial insects

that can help in mealybug treatment, too. Green

lacewings feed on the crawler stage of almost any

mealybug, where some others are more specialized – like the mealybug destroyer (Cryptolaemus

montrouzieri). This beneficial insect is a type of

ladybug that loves to feed on most mealybug species. Mealybugs can be controlled if the timing of

the initiation of the treatment is planned correctly

at the crawler stage.



References

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Ben-Dov Y (2012) ScaleNet. World Wide Web electronic

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and regression of a grass infesting mealybug, intro-



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(1999) Influence of Rhopus nigroclavatus

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T (1998) Identification of mealybug- (Homoptera:

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control of rhodesgrass scale by airplane releases of an

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20(1):46



67



Forest Plants

R. Sundararaj and M. Mani



Mealybugs often cause serious damage to the

growth of forest tree species particularly in nurseries and plantations. The damage is caused by

sap sucking resulting in dieback symptoms and

secreting copious amount of honeydew on which

black sooty mould fungus develops. Often the

infestation results in drying of branches causing

dieback of branches and ultimately death in seedlings and trees. The affected flowers wither and

fruits dry up, fall off prematurely. The seedlings

and trees affected severely by mealybugs shed

their leaves and look like sickly appearance and

in some cases drying of branches in trees and

death of seedlings. Most of the mealybugs are



highly polyphagous and have many collateral

hosts and hence, they can spread very rapidly to

the neighbouring plants.



Ferrisia virgata on S. album



Ferrisia virgata on P. pinnata



R. Sundararaj (*)

Institute of Wood Science and Technology,

Bangalore 560 003, India

e-mail: rsundariwst@gmail.com



M. Mani

Indian Institute of Horticultural Research,

Bangalore 560089, India



67.1



Ferrisia virgata



The striped mealybug Ferrisia virgata (Cockerell)

is covered with powdery white wax and has a pair

of purplish dorsal stripes along the back. It is

reported to breed on leaves, stem and fruits of

large number of tree plants including Azadirachta,

Anacardium, Annona, Artocarpus, Caesalpinia,

Casuarina, Cassia, etc. in India (Ali 1970). On a



© 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_67



607



R. Sundararaj and M. Mani



608



variety of host plants, it was most active during

August-November and March-April but very

much reduced during December-January (Rawat

and Modi 1968). Ferrisia virgata was found

infesting Santalum album in India (Sundararaj

et al. 2006).

It is emerging as an important pest on

Pongamia pinnata. Nymphs and adults were

found sucking the sap from both the surfaces of

leaves as well as tender shoots and flowers of P.

pinnata at the time of formation of new foliage



and flowering. During this period, it infests

almost all parts of tree. The affected flowers

wither and fruits dry and fall off prematurely. Its

infestation starts from February reaching peak

during March and April and then it declines in

Karnataka (Mangala et al. 2012). An infestation

by F. virgata was reported on four tree species

(Albizia lebbeck, Gliricidia sepium, Leucaena

leucocephala and Cassia siamea) in a screen

house at IITA main station, Ibadan, Nigeria

(Kadiata et al. 1992).



Ferrisia virgata on white leadtree



Nipaecoccus viridus on S. album



67.2



and two species of dipteran parasitoids

(Sundararaj et al. 2006; Sundararaj 2008). N.

viridis has been reported on Dalbergia sisso in

India. In Egypt, the lebbeck mealybug was particularly destructive to the lebbeck tree, Albizia

lebbeck. Releases of C. montrouzieri has resulted

in establishment but were of limited effectiveness

(Hall 1927). Two encyrtid parasitoids, Anagyrus

aegyptiacus Moursi and Leptomastix phenacocci

Compere were introduced from Java and established. Parasitization levels soared to 98 %, providing complete biological control, so that it was

difficult to find the host (Clausen 1978; Dahlsten

and Hall 1999). Population of N. viridis was sig-



Nipaecoccus spp.



The spherical mealybug Nipaecoccus viridis

(Newstead) occurs on foliage, stem, branches and

root of sandal (Chatterjee and Bose 1933). It is

also known to infest Acacia karroo, Ficus carica,

Grevillea robusta, Spathodea campanulata and

Tamarindus indica (http://www.plantwise.org/

KnowledgeBank/Datasheet.aspx?dsid=36335.

On Santalum album, the mealybug infestation

was found throughout the year with two peaks of

population the first during April-May and the

other during February-March. Besides, it was

found parasitized by ten species of hymenopteran



67 Forest Plants



nificantly higher on branches of the woody

legume Leucaena leucocephala in northern

Guam, Mariana Is. Cryptolaemus was found

feeding on N. viridis (= N. vastator) infesting

several plants in Guam but the predator was not

feeding preying N. viridis when it occurred on

woody legume L. leucocephala. It might be due

to the presence of amino acid mimosin derivative

which might have acted as feeding deterrent

through the host (Muniappan et al. 1980). The

presence of the ants Technomyrmex albipes (Fr.

Smith) decreased the percentage of N. viridis

parasitized by the encyrtid Anagyrus indicus

Shafee et al. and the mortality of mealybugs was

attributed due to parasitism by A. indicus and predation by other arthropods. Natural enemies play



Rastrococcus iceryoides on P. pinnata



67.4



Nipaecoccus nipae



Nipaecoccus nipae (Maskell) (Pseudococcus

nipae) completely defoliated Erythrina glauca

each year but since the introduction of C. montrouzieri, there is no economic importance of

this pest on the above tree in Puerto Rico

(Martorell 1940).



67.5



Rastrococcus iceryoides



The mango mealybug Rastrococcus iceryoides

(Green) has been reported on several tree plants

including Ficus indicus, Mangifera indica,



609



an important role in maintaining N. viridis populations at low levels (Nechols and Seibert 1985).



67.3



Nipaecoccus filamentosus



Nipaecoccus

filamentosus

(Cockerell)

(Pseudococcus filamentosus) has been recorded

on limes, Tamarix stricta, Ficus carica [figs],

Vitis sp. and Nerium oleander in Iran. There were

four generations annually in the Fars region. The

coccinellid Cryptolaemus montrouzieri has been

imported from northern Iran and has proved to be

effective as a biological control agent of N. filamentosus (Khalaf and Aberoomand 1989).



Paracoccus marginatus on teak leaf



Pithecellobium saman, Samanea saman, S.

album, Wendlandia notoniana, Zizyphus mauritiana, Tephrosia candida, Vitex sp. (Varshney

1992). It is reported to infest on Pongamia pinnata in and around Bangalore. Both the nymphs

and adults suck the plant sap from leaves and

sooty mould develops on the honey dew excreted.

The extent of infestation was more (23 %) in

younger plantations and lower (8.0 %) in older

plantations. In some cases, due to severity of

infestation, the leaves gradually dried resulting in

defoliation of trees (Mangala et al. 2012;

Sundararaj and Devaraj 2010). Rastrococcus

invadens was also recorded on Ficus sp. in Sri

Lanka (Galanihe and Watson, 2012).



R. Sundararaj and M. Mani



610



67.6



Maconellicoccus hirsutus



M. hirsutus (Green) (PHMB) was known to infest

Acacia arabica and Albizzia lebbak in Egypt.

Maconelicoccus hirsutus was detected in teak

plantations in 2004 in the Banderas valley in

Mexico. A biological control programme was initiated in May 2004 to release 210,000 of the

predator Cryptolaemus montrouzieri on 150 ha.

Damage to trees was reduced by 92 %. In India,

it has been reported on Samanea saman, Tectona

grandis, Tabeubuia rosea, Delonix regia (Anand

Persad and Khan 2006), Ficus cunia, F. religiosa,

F. indica (Ayyar 1930; Varshney 1992). In Bahia

de Banderas, Nayarit, Mexico, the parasitoid

Anagyrus kamali Moursi regulated the population growth of Maconellicoccus hirsutus on teak.

The average reduction of the pest was 96.5 % in

30 days after release (Garcia-Valente et al. 2009).

M. hirsutus was found infesting Casuarina equisetifolia in Andhra Pradesh (Murthy et al. 1997)

and Ficus trees in Gujarat, India (Muralidharan

and Badaya 2000).



67.7



Humococcus resinophilus (Green) in northern

India is a pest of Pinus roxburghii regeneration.

As a result of heavy infestations, branches apparently turn black and die (Ben-Dov 1994).



67.8



Paracoccus marginatus



In multi-tier agroforestry ecosystems of Kerala,

India, the invasive mealybug Paracoccus marginatus Williams and Granara de Willink infestation

was reported from teak, rubber, and other such

plantations of Kerala even though the incidences

were highly localized. In the case of young teak

plantations, the immediate action taken was to

chop off the infested branches and burn them.

Subsequently the exotic parasitoid Acerophagus

papayae was released in the forest ecosystem to

control Pa. marginatus.



67.9



Saman tree killed by heavy

PHM B infestation



Humococcus resinophilus



Planococcus vovae



Planococcus vovae (Nasonov) was known to

infest cypress trees in Shiraz, Iran. A total of 15

species of natural enemies was found attacking

cypress tree mealybug Pl. vovae. These included

two parasitoids, Anagyrus pseudococci (Girault)

and Dusmetia fascipennis (Noys & Hayat). The

most common predators included Exochomus

quadripustulatus (L.) Hyperaspis polita Weise,

Nephus bipunctatus (Kugelann), Chrysoperla carnea (Stephens), Suarius fedtschenkoi (McLachlan

in Fedchenko), Dicrodiplosis manihoti Harris and

Geocoris quercicola Linnavuor (Lotfalizadeh and

Ahmadi 2000) and Coccidoxenoides perminutus

Girault (Talebi et al. 2008). P. vovae is a common

pest of cypress trees in Greece (Milonas and Kozar

2008). C. montrouzieri adults and larvae were

detected in Turkey during May and June on cypress

trees (Cupressus sempervirens L.) heavily infested

with P. vovae (Yigit and Canhilal 1998). It was

found attacking the conifers, e.g., Chamaecyparis,

Cupressocyparis, Cupressus, Libocedrus and

Thuja in Poland. Insecticides Actellic [pirimiphosmethyl] 500 EC and Ultracid [methidathion] 40

EC for its control were recommended (Golan and

Jaskiewicz 2002).



67 Forest Plants



Planococcus vovae



611



Oracella acuta on slash pine



67.10 Phenacoccus azaleae

The Bunge Prickly-Ash tree plant (Zanthoxylum

bungeanum) damaged by the mealybug

Phenacoccus azaleae Kuwana which attracts its

natural enemy, the ladybug Harmonia axyridis

(Pallas), was studied in Tainhang Mountain Area

of Shanxi Province, China, during 1999–2001

(Xie et al. 2004).



67.10.1 Oracella acuta

The mealybug Oracella acuta (Lobdell) is native

to the south-eastern United States. Hosts of this

mealybug include loblolly (Pinus taeda L.), slash

(Pinus elliottii Engelm.), Virginia (Pinus virginiana Miller), shortleaf (Pinus echinata Miller),

and longleaf (Pinus palustris Miller) pine (http://

forestpests.org/vd/7047.html). O. acuta was accidentally introduced into Guangdong, southern

China, in 1988 on scions of slash pine (Pinus

elliottii) and found damaged pine trees (Sun

Jiang Hua et al. 1996). Mealybugs either settle on

the shoot or occasionally between the needles

near the fascicle. Females secrete a characteristic

white resin cell that covers their body. The tips of

new shoots are the preferred settling site, though

the entire shoot may be colonized when populations are high. The resin cells, shoots, and needles may become covered with black, sooty

mould growing on honeydew produced by the

mealybug. Infestations rarely cause tree mortality,



Close up of the mealybug



but they may severely retard growth (http://forestpests.org/vd/7047.html). Three native parasitoids, Zarhopalus debarri Sun, Acerophagus

coccois Smith and Allotropa oracellae Masner

help regulate this mealybug’s population size in

the southeast United States. All three parasitoids

were imported to China and released in heavily

infested slash pine plantations (Clarke et al. 2010).



67.10.2 Pseudococcus viburni

(=Pseudococcus obscurus)

Judas tree, Cercis siliquastrum, is a small deciduous tree from Southern Europe and Western Asia

which is noted for its prolific display of deep pink

flowers in spring. Heavy predation by

Cryptolaemus montrouzieri was observed on Ps.

viburni (Signoret) infesting Judas trees in avenues of Turin resulting in small mealybug population in subsequent years (Arzone 1983).



67.11 Peliococcus serratus

American Beech Fagus grandifolia is an important tree in forestry. Peliococcus serratus (Ferris)

was known to attack F. grandifolia in Maryland,

USA. The mealybug had two generations in a

year. The eggs were laid in an ovisac on the bark

in June-August (hatching in 7–10 days) and in

October-November (these overwintering, hatching in late April or early May). Limiting factors



R. Sundararaj and M. Mani



612



included adverse weather conditions, parasitoids

and predators (Russell 1987).



67.15 Palmicultor lumpurensis

and Chaetococcus bambusae



67.12 Pseudococcus aurilanatus



Palmicultor lumpurensis (Takahashi) and

Chaetococcus bambusae (Maskell) had established in Florida, USA. The potential economic

impact of these invasive species for Florida’s

bamboo is not yet known. Monitoring of populations from each of these invasive species will be

important for the native bamboo species,

Arundinaria gigantea, and for ornamental bamboo stands (Hodges and Hodges 2004). The bamboo mealybug Palmicultor lumpurensis causes

considerable damage to the host plant. New

shoots are more susceptible to damage and heavy

populations can cause abortion of new shoots.

Severe infestations could potentially kill stands

of bamboo.



In South Australia, C. montrouzieri played a key

role in controlling the golden mealybug,

Pseudococcus aurilanatus (Maskell) – a serious

pest of Norfolk Islands pines, Araucaria excelsa

(Vosler 1920).



67.13 Plotococcus spp.

Plotococcus capixaba Kondo was found infesting the leaves of the jaboticaba tree, Myrciaria

jaboticaba at Espirito Santo and Leandra erinacea at Sao Paulo. Plotococcus hambletoni Kondo

was collected in Sao Paulo on a myrtaceous plant

(Kondo et al. 2005).



67.14 Antonina spp.

Bamboo node mealybugs, Antonina sp., in the

absence of attending ants, produced long waxy

filaments both in the greenhouse and in the field

conducted in the Philippines. In contrast, antattended mealybugs had only very short filaments

or none at all. Ant exclusion experiments using

potted Bambusa tuldoides and B. vulgaris var.

vitatta confirmed the field observations. The

available data suggest that the long filaments are

an adaptation for the dispersal of honeydew in the

absence of solicitous ants to avoid drowning in

the accumulating honeydew or suffocation due to

development of sooty moulds (Lit et al. 1999).

Eleven species of Antonina were reported on

bamboos from Taiwan, China, Japan, and the

U.S. (California) (Williams and Miller 2002).



Palmicultor lumpurensis



67 Forest Plants



613



67.16 Dysmicoccus obesus



67.20 Dysmicoccus spp.



Dysmicoccus obesus (Lobdell) was found in

Arkansas living in crevices under bark scales of

loblolly pine trees (Pinus taeda). Most individuals (77 %) were found on the bole between 0 and

90 cm of the ground, and they showed slight preferences for the northern and southern bole exposures. Individuals of the formicid Crematogaster

were observed tending the mealybug. Three

broods per year were detected, with adults produced in May, July and September. It is suggested

that D. obesus probably overwinters off the tree

as immatures. The documented occurrence of D.

obesus from ten southern and south-eastern states

in the USA suggests that its distribution is probably throughout the range of its host, P. taeda.

Records from Maryland indicated that the pseudococcid also feeds on Virginia pine (P. virginiana) (Thompson and Colvin 1990).



Serianthes nelsonii is a large tree endemic to

Guam and Rota of the Mariana Islands. Three

species of mealybugs, Dysmicoccus neobrevipes

Beardsley, D. brevipes (Cockerell), and

Planococcus citri (Risso), feed on the leaves, leaf

buds, branch tips, and roots of trees and seedlings. On the cultivated tree in Yona, up to 40 %

of the branch tips were killed every two weeks by

a combination of D. neobrevipes and P. citri.

Most mealybug colonies were removed by predators, including the lady beetle Nephus roepkei

(Fluiter) (Coccinellidae). Seedlings may remain

vulnerable to mealybugs for longer periods of

time; malathion effectively killed the mealybugs

on the seedlings (Gary et al. 1996).



67.17 Chaetococcus sp.

On the bamboo Gigantochloa scortechinii in

Malaysia, the ant Tetraponera sp. was found to

be always associated with the pseudococcid

Chaetococcus sp. (Klein et al. 1992).



67.18 Pseudococcus baliteus

In Philippines, Pseudococcus baliteus Lit was

recorded on prop roots of Ficus elastica (Lit and

Calilung 1994).



67.19 Acaciacoccus spp.

Acaciacoccus hockingi Williams and Matile was

recorded in swollen thorns of Acacia drepanolobium in Tanzania. The species was tended by

Crematogaster nigriceps prelli. It was not found

without this formicid in attendance and appeared

to be reliant on C. n. prelli to remove honeydew

from the thorns (Williams and Matile-Ferrero

1994)



67.21 Management

Inspecting seedlings and young trees regularly is

essential for early detection. The branches, heavily infested by these coccid bugs, should be

lopped and burnt. Eggs of the mealybugs, protected by waxy filamentous secretions of ovisacs,

are almost impossible to reach with insecticides.

Late instar nymphs and adult female mealybugs

are not affected by foliar application of insecticides since they are covered with waxy coating.

Besides, spraying with suitable insecticides may

not be economically and environmentally viable.

Hence, biological control particularly the third

type that involves the supplemental release of

natural enemies is the best control option in forestry. Among the predators, coccinellids commonly known as ladybird beetles are mainly

free-living species that consume a large number

of preys during their lifetime. They feed on mealy

bugs, and other injurious insect and mites and

keep the insect populations under control. Proven

natural enemies of the respective mealybug species can be used for their suppression on forest

plants. Hence, it is vital to exploit natural enemies to develop ecologically and environmentally sound insect pest management in forestry

(Table 67.1).



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16 Dysmicoccus dennoi & Trionymus clandestinus

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