| Country or region name |
Japan |
| Organism group |
insect |
| Order name |
Lepidoptera |
| Family name |
Gelechiidae |
| Species name |
Phthorimaea operculella |
| English common name |
potato tuber moth, potato tuberworm, potato split-worm |
| Substantially same species (synonym) |
|
| Year of invasion or detection |
1953 |
| Native region |
Central-South America |
| Situation of establishment |
Category 4: Settled after 1951, but not distributed all over the
country |
| Taxonomic description |
| |
| Expansion of distribution area |
| In Japan, Phthorimaea operculella was first found in 1953 in Hiroshima Prefecture, and its distribution
area has been expanded over the warm temperate regions of Japan. This species
infests some Solanaceae plants, such as potato, tobacco, eggplant and so
on. Tubers of potato are given severe damage by the larvae.
In Japan, Phthorimaea operculella was first found in 1953 in Hiroshima Prefecture from cultivated tobacco.
Its distribution area has been expanded over the western half of Japan
until 1963, and northward to Fukushima Prefecture (southern part of Tohoku
region) until 1971. It is not presently distributed in Hokkaido and Northern
Tohoku region.
|
| Environmental impact |
| Potato: Yong larvae mine in the leaves and make linear silver blotches,
becoming larger later. Mature larvae tunnel into the tubers underground
and in storage. |
| Economic damage |
| Infested tubers generally become rotten under warm conditions. Eggplant
and Tobacco: Larvae infest leaves in the same way as in potato. They also
tunnel into stems, causing cease of stem growth. In eggplant, they occasionally
enter fruits through calyx, and devour inside. |
| Reproduction |
| |
| Growth |
| The eggs are laid singly on the under side of the leaf, or in tubers
near the eye. Each female lays 30-80 eggs. The developmental zero is 11.0
degree centigrade for egg, larva, and pupa. One generation can be completed
in one month at 25, two months at 18, and about three months at 15 degree
centigrade. There are 6 to 8 generations per year in the temperate area
of Japan. This species overwinter in all stages in the warm temperate regions
of Japan. However it can not in the cold area, because it does not have
a diapausing stage. |
| Countermeasure |
| Some insecticides such as chlorfenvinphos, methomil, aceephaate
are effective to control larvae infesting leaves and stems. Since large
larvae have some tolerance to chemicals, it is important to apply those
in young instar. To prevent from egg laying by female moths on potato tubers,
tubers should be covered by soil not to be exposed during cultivation.
|
| Writer's name and affiliation |
| © Written by Yasuda, K. National Institute for Agro-Environmental
Science.(Written on 9, Nov. 2004) |
