Hypsipyla Shoot Borers of Meliaceae in Sri Lanka - Australian ...

Hypsipyla Shoot Borers of Meliaceae in Indonesia
Oemijati Rachmatsjah 1 and F.R. Wylie 2
Abstract
In Indonesia, Hypsipyla robusta (Moore) has been recorded from the native Toona sureni
(Blume) Merr. and several introduced species, principally Swietenia macrophylla King. Impact has
been severe, particularly on the mahoganies, trees aged three to six years and two to eight metres
tall being the most heavily damaged. In Java, H. robusta completes its life cycle in about five
weeks, peak flight activity occurring around dusk in the early rainy season (October). Several
methods have been tested to control the insect, including form pruning, closer spacing at planting,
the use of nurse, barrier and mixed plantings, and insecticide application. However, effective
management of H. robusta has not yet been achieved.
THE SHOOT BORER Hypsipyla robusta (Moore) is
known to feed on most tree species of the subfamily
Swietenioideae in the family Meliaceae. In Indonesia,
its most noticeable impact has been on the
mahoganies, Swietenia macrophylla King and
S. mahagoni (L.) Jacq., introduced into the country
in the late 1800s and extensively attacked by the
mid-1920s (Morgan and Suratmo 1976). These
species are favoured for planting because of their
high value timber. When young, they are often
attacked by H. robusta, resulting in highly branched
trees of inferior value due to a large reduction in
straight bole length and timber volume. Several other
species of Swietenioideae have been trialed, mainly
in Java, but most have been attacked by the shoot
borer.
Biology of Hypsipyla robusta
Hypsipyla robusta appears to be very widespread in
Indonesia, being recorded from the islands of Java,
Sumatra, Kalimantan, Sulawesi and Maluku. It is
found in an altitudinal band ranging from the lowlands
through to 1100 m above sea level (Suharti and
Santoso 1990).
1 Faculty of Forestry, Bogor Agricultural University,
PO Box 168, Bogor 16680, Indonesia
2 Queensland Forestry Research Institute, PO Box 631,
Indooroopilly Qld 4068, Australia
31
Following on early work by Kalshoven (1926), the
morphology and biology of H. robusta in Java have
been studied in some detail by Indarwati (1980), and
its host preferences by Morgan and Suratmo (1976).
Light trap catches and observations by the latter
authors in West Java showed that, while generations
are continuous throughout the year, the moth is most
active during the period early September to early
December. Flight activity of the adult is greatest
around dusk in the early rainy season (October) and
copulation and egg-laying occur during the night.
Indarwati (1980) found that individual female H.
robusta can produce up to 472 eggs, with an average
incubation period of seven days. Newly hatched
larvae bore through the epidermis of the growing
shoot and mine in the twig. There are four or five
larval instars occupying about 19 days (Morgan and
Suratmo 1976). Usually, each shoot contains only
one larva. Pupation is mostly within the twig mines
or in silken cocoons in the foliage, and takes 10 days.
The adult lives on average four days. The life cycle
of H. robusta in Java is thus about five weeks
(Morgan and Suratmo 1976).
Damage to Meliaceae
In Indonesia, H. robusta is known to feed on the
native Toona sureni (Blume) Merr. and the
introduced Carapa guianensis Aubl., Cedrela
odorata L., Chukrasia tabularis A. Juss., Khaya
anthotheca (Welw.) C.DC., K. grandifoliola C.DC.,