Movement of adult Monochamus alternatus was investigated on young black pine, Pinus thunbergii, trees for about one month in a screen cage. Number of pine trees to which M. alternatus females and males moved during the experimental period was 6.4±1.4 and 7.2±1.5 out of 15 trees, respectively. Adult females and males moved to 0.2±0.1 and 0.3±0.1 tree per day, respectively. A 74.6 and 80.7% of adult females and males moved at night (17:00-08:00) to other trees. After moving, most beetles (72.6% of females and 76.0% of males) stayed on the tree to which they moved for one to two days. Some beetles stayed for up to seven days.
We investigated moth communities in Samcheok, Korea, to elucidate the influence of the East Coast Fire in 2000. Moths were collected with UV light traps 4 times a year from 2006 to 2009 at 3 sites: Unburned area (Site 1), Surface fire area (Site 2), and Crown fire area (Site 3) sites, respectively. A total of 3,804 individuals belonging to 727 species from 30 families were captured at the 3 study 1,727 individuals of 505 species (27 families) at Site 1, 1,193 individuals of 353 species (24 families) at Site 2, and 885 individuals of 340 species (25 families) at Site 3. Species richness and individuals of Noctuidae, Pyralidae, Geometridae, and Tortricidae were the highest at all 3 sites. All of species richness, individuals, and species diversity (H’) were the highest in Site 1 for 4 years. The index of similarity (α-Index) was higher between Site 2 and 3 in 2006, while higher between Site 1 and 2 in 2009. Moths were grouped into 16 categories by hosts of the larval stage. Individuals of moths of herbaceous feeding habit continuously decreased at Site 3, but proportion of individuals of tree feeding habits continuously increased. The present results showed that moth communities was relatively recovered according to vegetation change after forest fire and regeneration of moth communities in surface fire area was more faster than in crown fire area.
Three species of the genus Neolygus Knight - N. hakusanensis (Yasunaga, 1991), N. roseus (Yasunaga, 1991) and N. zhugei (Yasunaga, 1991) - are recognized for the first time in Korea. An identification key to the eleven Korean Neolygus species is presented. Some illustrations of male genitalic structures are also provided.
Twenty-five species of pests had occurred at orchards of Japanese Apricot, Prunus mume Siebold & Zucc., in Hadong and Jinju (Gyeongsangnam-do province) from 2005 to 2007. Rhopalosiphum rufiabdominale (Sasaki), Singapora shinshana M., Tetranychus viennensis Zacher, and Synanthedon hector B. occurred as major pests and Anthonomus persicae sp. nov., Grapholita molesta (Busk), Spodoptera litura F., and Myzus persicae (Sulzer) as a sporadic pests. The population of S. shinshana had increased continuously during the season, from late April to late October. The population of T. viennensis occurred early May, reached the highest peak in late June to early July, and then declined with worsening consequences of nutritional conditions in the apricot leaves. A. persicae was observed to occur before breaking flower-bud of apricot and emerged adults were found in April to early May.
A remote sensing pheromone trap called IT pheromone trap (Korean patent: 10-0982563) was applied to monitor overwintering population changes of the oriental fruit moth, Grapholita molesta, for three successive years in apple orchards. Males of the overwintering populations were attracted during April and May. However, the occurrence peak was delayed and extended to early June in 2010, at which the average spring temperature was significantly lower than the previous years. These overwintering populations could be monitored by the remote-sensing pheromone trap. When the remote-sensing pheromone traps were deployed to apple orchards of different provinces in Korea in 2010, the maximal overwintering populations of G. molesta were monitored at May in all areas. However, the population sizes monitored were significantly different among different localities. This study suggests a practical application of IT pheromone trap to monitor G. molesta in field conditions.
This study analyzed effects of different sound treatments in frequencies and intensities on digestion and immune physiological processes of the beet armyworm, Spodoptera exigua larvae. Without effect on egg hatch, sound treatments with 100-5,000 ㎐ at 95 ㏈ suppressed feeding behavior and inhibited a digestive enzyme activity. In addition, two dimensional electrophoresis of midgut luminal proteins indicated a marked difference of the sound-treated larvae. In response to 5,000 ㎐ at 95 ㏈, larvae showed a significant decrease in hemocyte nodule formation against fungal challenge along with significant suppression in phospholipase A₂ activity in hemocyte and plasma. With increase of sound frequencies, the treated larvae showed an enhanced susceptibility to insecticides. Such sound frequency effect was significantly modulated with different sound intensities. These results suggest that sound treatment may give adverse stress to physiological processes of S. exigua larvae and may be applied to a nonchemical insect pest control.
The seasonal occurrence of Riptortus pedestris Fabricius was investigated using pheromone traps baited with its aggregation pheromone in the fields with various crop composition (mixture culture of barley and hairy vetch in Asan, Chungnam, monoculture of hairy vetch in Yuseung, Daejeon) from mid-May to mid-July of seed gathering season in 2010. The invasion of R. pedestris into the experimental fields began to increase rapidly from late-June in which period hairy vetch and barley reach the beginning of seed formation stage. After seed gathering season in mid-July, the invasion rate of R. pedestris decreased, and the activity was continually observed till early-November. In addition to dominant R. pedestris species, 33 species of hemiptera including Apolyaus watajii, Dolycoris baccarum, Adelphocoris suturalis, and Yemma exlis were collected, which indicated abundant species diversity in the hairy vetch fields. In the laboratory, R. pedestris did not developed successfully to adult stage on food sources of hairy vetch, with decreasing survival rate after 4th instar and the failure of emergence to adult stage. Also, R. pedestris showed higher preference on soybeans than hairy vetch. Consequently, hairy vetch may be not true host for the development and survival of R. pedestris. It is considered that R. pedestris is a temporary visitor at the season of seed formation in hairy vetch fields
This study was conducted to develop an artificial diet for the mugwort looper, Ascotis selenaria (Lepidoptera: Geometridae), which is an insect pest to leaves of citrus (Citrus unshiu). Corn and soybean powder were selected as main nutrient sources for larvae of A. selenaria after several diets consisted of wheat germ, corn, kidney bean and/or soybean were tested for larval development and survival. A higher amount of the main nutrients in the diet increased the larval survivorship. Addition of yeast and cholesterol in diet increased the larval survivorship. Finally the composition of diet was decided as followings, corn 100 g, soybean 100 g agar 25 g, Brewers’ yeast 30 g, cholesterol 0.5 g, Vanderzant vitamin mixture 2 g, Wesson’s salt mixture 2 g, sorbic acid 2 g, ascorbic acid 2 g, and methyl-4-hydroxybenzoate 2.5 g, and distilled water 1 liter. Development periods of larvae and pupae, survival rate and fecundity of A. selenaria reared on the diet were not significantly different with those on the host plant, citrus leaves. Larvae of early instars were reared in a group, while larvae of later instars (5-6th) were reared individually. Adult mating was conducted in a plastic cage and an oilpaper covered with a gauze was provided as an oviposition site.
Micromus variegatus (Neuroptera: Hemerobiidae) is reported here as new to South Korea. In addition, three other hemerobiid species recorded only the collection data, Hemerobius harmandinus, Sympherobius tessellatus and S. domesticus are also reported with a brief description, images of the adult and wings, and its Korean common name. With four previously reported species in Korea, there are eight species of the family Hemerobiidae from Korea.
The legless mealybug, Antonina nakaharai Williams and Miller (Hemiptera: Pseudococcidae) is recorded from bamboos (Poaceae) in Korea. An identification key to adult females of three species of Antonina from the Korean Peninsula is also provided.
Two species of the genus Andaspis, Andaspis crawii (Cockerell) and Andaspis kashicola (Takahashi) are newly recorded in the Korean fauna of armored scales (Diaspididae). A key to species of Andaspis, illustrative photographs and information on the distribution and hosts of each species, are also provided to identify the specimens of Andaspis collected in Korea.
Biological control of Aphis gossypii by natural enemies was carried out in watermelon from April to June. Aphidius colemani was released 3 times at rate of 2/㎡ to control A. gossypii(April 24, May 8, and May 22 in 2007). In A. colemani-released plots, A. gossypii showed low population density of < 0.6 per leaf with the highest parasitism of 57.2%, and 2.0~10.6% in the percentage of leaves with aphids. In control, the population of A. gossypii kept on increasing from early May and reached 653.2/leaf on may 29.