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Archives (2000)
Study identifies dynamics
of jackfruit
infestation
by Mario A. Martinez and Rufino
B. Ayaso, III |
July-September
2000
|
With a recorded 18 commercial and non-commercial
uses, jackfruit (Artocarpus heterophyllus Lam.) displays
great export potential specially as the fruit is gaining increased
popularity beyond Asian shores. The Department of Agriculture
(DA) has made jackfruit one of its banner commodities, attesting
to this fruit's foreign earning generation capacity.
 In
Eastern Visayas, efforts are underway to commercialize this
crop. But the full commercialization of jackfruit, like other
crops, encounter numerous problems which all result to low
yields. Insect pest attack is the most predominant obstacle
to the growth of the industry in the said region. Jackfruit
is considerably attacked by fruit fly (Bactrocera umbrosa
Fabr.) during the fruiting period, according to Coronel (1979).
In any crop production scheme, crop protection
is always crucial to prevent insect-pest infestations. Crop
protection activities include: a) pest identification, b)
population fluctuation, c) assessment of damaged done by the
insect pests and d) understanding of some biological information
of the insect pests (life cycle, mortality, alternate host,
and natural enemies attacking of insect pests).
However, literature or information on insect
infestation conditions, in Eastern Visayas in particular,
is not available.
A study was conducted in Eastern Visayas to
identify the dynamics of insect pests associated with jackfruit.
The study identified insect pests that attacked the crop in
the provinces of Leyte, Southern Leyte, Samar, Northern Samar
and Eastern Samar. It also determined the population fluctuation
while developing an understanding of the basic biological
information, assessing the damage inflicted by the major insect
pests and establishing a management system for the major insect
pests.
Monthly surveys and sampling of the insect pests
from the selected municipalities of the above provinces revealed
10 insect pests that attack the crop - bark borer/stem borer,
gray mealybug, pink waxy scale, cottony cushion mealybug,
white grub, red worm, fruit fly, fruit borer and leaf weaver.
These pests are present throughout the year and infest the
crop at various stages of growth and at various parts.
Fruit fly (Bactrocera umbrosa) and pyraustid
and curcullionid fruit borers were the most dominant in terms
of number and damage inflicted. The insect feedings considerably
destroyed the fruits of the crop.
The pyraustid and curcullionid fruit borers
are newly identified insect pests. The overall metamorphosis
and the natural controlling factors of these borers were determined
under laboratory conditions. In the cages and glassware, the
borers are capable of producing several generations given
their total life cycle (33.8 days for pyraustid fruit borer
and 65.8 days for curcullionid fruit borer). However, in the
actual crops, their life cycles were higher. Mortality of
the borers in its original host is higher during the first
instar period of the larva and tends to decrease as the growth
of the insect-pests progresses. Collected larvae from the
field showed parasitism by Apanteles sp., a hymenopterous
parasite.
The control of fruit fly and fruit borers attacking
jackfruit was also studied. Five strategies of control against
fruit fly on jackfruit were tested. The use of Dipterex (0.75
kg ai/ha applied at the fruit setting and bi-weekly thereafter)
and bagging the fruits earlier effectively reduced infestation.
(For more information, please contact Mr.
Ayaso, EVIARC, Abuyog, Leyte, or call at tel no. 062- 3332537
or e-mail at daeviarc@tac.weblinq.com)
More Articles:
Vol. 2 No. 3
July-September 2000
»» 1st week of oct is "nat'l agriculture,
fisheries R&D week"
»» Mulching
arrests uneven fruit ripening in durian, study reveals
»» Philippine mangoes break into world market
»» National integrated RDE agenda and program
for fruits
»» Sweet tamarind propagation and management
»» Micropropagation: propagating coconut
through tissue culture
»» Study identifies dynamics of jackfruit
infestation
»» Accelerating coconut replanting program
through biotech
»» Ensuring fruit quality and longevity through
HWD
»» Transgenic fish 21st century solution
to decreased fish farming productivity
»» Early detection of viral infection in
shrimps possible through use of new protocol
»» New technique to boost shrimp industry
[More
2000 Articles]
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