New Horizons in Insect Science Towards Sustainable Pest Management

362 A. D. N. T. Kumara et al.

the pest is reported in almost 15 % of the global
coconut-growing countries and in nearly 50 % of
the date palm-growing countries (Faleiro 2006 ).
It prevails wherever palms are cultivated. The
geographical spread of the RPW is mainly due
to human intervention, by transporting infested
young or adult date palm trees and offshoots
from contaminated to uninfected areas (Alhu-
daib 1998 ; Gomez and Ferry 1999 ; Al-Saqer
and Hassan 2011 ). Menon and Pandalai ( 1960 )
suggested that R. ferrugineus is a serious pest of
coconut palms in India. It damages 34 % of the
coconut groves in Cochin, India. In Sri Lanka, it
is the most serious pest causing fatal damage to
young coconut palms of 3–10 years old (Brand
1917 ; Kirthisinghe 1960 ). It has been estimated
that 10 % of young coconut palms in the coun-
try is lost annually due to its attack (Mahinda-
pala 1993 ). Accordingly, in 2000–2005, nearly
200,000 young palms have been killed by the
RPW resulting in US$ 1,800,000 loss (Siriward-
ana et al. 2010 ). The RPW was first reported on
coconut from Southeast Asia, and its host range
included 19 palm species worldwide (Malumphy
and Moran 2007 ).The list of known hosts in-
clude: Cocos nucifera (coconut palm), Phoenix
canariensis, Areca catechu, Arenga pinnata,
Borassus flabellifer, Caryota maxima, Caryota
cumingii, Corypha gebanga, Elaeis guineensis,
Corypha elata, Livistona decipiens, Metroxylon

sagu, Oreodoxa regia, Phoenix dactylifera (date

palm), Phoenix sylvestris, Sabal umbraculifera,

Trachycarpus fortunei, and Washingtonia spp.

However, sugarcane and Agava americana are

used for laboratory rearing although their infesta-

tion in the field is not clear (Abraham et al. 1998 ).

Bioecology

The life cycle of the RPW varies between 45 and

139 days depending on environmental and geo-

graphical conditions and is spent inside the palm

itself (Faleiro 2006 ; Esteban-Duran et al. 1998 ;

Murphy and Briscoe 1999 ). The four stages of

life cycle (Fig. 3 ) vary depending on egg, larva,

pupa, and adult. The duration of each life stage

and their numbers varies on host substrate and

climatic factors (Table 1 ).The female RPW lays

eggs, ranging from 58 to 531 in quantity, in the

cracks, wounds, or crevices on the trunk of the

tree. The light-yellow eggs (2.5 mm long) are laid

close to the surface of the incision or wound. The

grubs are white-yellow, and the larvae hatch from

eggs in 4–6 days. They start feeding themselves

by chewing the tissues of the plant and start mov-

ing toward the interior of the palm. The chewed

up palm tissues and the thick brown fluid are

oozing out from the tunnels of the trunk usually

visualized after feeding of grubs. The grub lives

Table 1 Three major insect pests of coconut
Common name Scientific name Family and order Number of species
(approximately)

Geographical

distribution

Pest status

RPW Rhynchophorus fer-

rugineus Olivier

Curculionidae,

Coleoptera

05 South Asia Major

Southeast Asia Major

Middle East Major

North Africa Major

Australia Invasive

Europe Invasive

North America Invasive

RB Oryctes rhinoceros L Dynastidae

Coleoptera

03 South Asia Major

Southeast Asia Major

Pacific Area Major

Africa Minor

Australia Invasive

BHC Opisina arenosella

Walker

Lepidoptera:

Oecophoridae)

01 South Asia Major

Southeast Asia Invasive