Hyung-Joo Yoon

Life Cycle of the Mulberry Longicorn Beetle, Apriona germari Hope on an Artificial Diet

Abstract Mulberry longicorn beetle, Apriona germari, was reared on an artificial diet to investigate its life cycle. Average egg period was 17.95 days. Most larvae pupated at the 8th (33.3%) or 9th (33.3%) instars, but others emerged from the 7th to the 11th instars. The total duration of larval stage from the 1st to the end of the 9th and the 11th instars were 176.2 and 251.5 days, respectively. For terminatiopn of diapause and acceleration of pupation, low temperature treatment at 5°C for 60 days was highly effective. Average pupal period for female and male was 19.3 and 18.4 days, respectively. Average longevity of adults was similar with 40.5 days for female and 44.3 days for male. Mating had occurred from about 10 days after the adult emergence, and then a female adult laid one or two eggs per day. Average number of eggs oviposited by a female was approximately 47.7. Total life span of A. germari, when reared on an artificial diet in the laboratory, ranged broadly from 197.5 days to 331.5 days mainly depending on the larval period.

Expressed sequence tag analysis of the diapausing queen of the bumblebee Bombus ignitus

We constructed a full‐length cDNA library from diapausing queens of the bumblebee Bombus ignitus. A total of 480 randomly selected clones was sequenced by single‐run 5′‐end sequencing. Of these, there were 437 high quality clones, 23 poor quality clones and 20 read‐fail clones. Each high quality clone sequence was searched against a public protein database. The most frequently found matching genes were ribosomal proteins (12.5%), p10 (3.58%), cytochrome P450 monooxygenase (3.13%) and sensory appendage protein (2.9%). Sequence similarity analysis between bumblebees and other insect species showed that 72 out of 437 (16.5%) bumblebee expressed sequence tags (EST) matched sequences of Apis mellifera, with matches to Drosophila melanogaster (6.6%), Caenorhabditis briggsae (6.2%), Lysiphlebus testaceipes (4.8%), Periplaneta americana (3.7%) and Anopheles gambiae (3.4%) following, suggesting that sequence similarity of bumblebee EST is closest to that of A. mellifera. Functional classification of EST based on Gene Ontology showed that most genes found by sequencing are associated with physiological processes in the bumblebee. The results of sequencing and analysis of our 437 cDNA demonstrated that high‐throughput EST sequencing and data analysis are powerful means for identifying novel genes and for expression profiling. Our bumblebee EST collection could be a useful platform for further studies of gene expression in diapausing bumblebees.

Comparison of the Colony Development of the Bumblebees, Bombus terrestris Produced from Domestic and Foreign Bumblebees Companies

We compared colony development and survival rate after artificial hibernation between the bumblebees, Bombus terrestris, produced from domestic and foreign companies. The number of worker and queen produced from foundation colony of three domestic and one foreign companies was 232.4-270.8 and 62.0-181.8, respectively, but there was no statistical difference. In colony development of B. terrestris queens which were terminated diapause by narcosis at different companies, oviposition rate, colony foundation and progeny-queen production of bumblebees produced from domestic companies were superior to those from foreign company. But foreign company in the number of worker and queen was superior to domestic companies. On the other hand, survival rate and colony development of B. terrestris queens, which were terminated diapause by artificial hibernation at three domestic and two foreign companies, were no significant differences. These results indicate that oviposition, colony foundation, progeny-queen production, and survival rate after artificial hibernation showed no differences between the bumblebees produced from domestic and foreign companies.

Development of an Apparatus for the Oviposition Induction of the Bumblebee Bombus ignitus Using Electricity

Bumblebees are widely used to pollinate crops in greenhouses and fields. Here we firstly developed an apparatus for the oviposition induction of the bumblebee Bombus ignitus using electricity. The apparatus consists of boxes for colony initiation, part of temperature control, part of heat transfer, and moving shelf. The result shows that the rates of oviposition and colony foundation in the newly developed apparatus are respectively 3.9% and 5.2% higher than in the existing apparatus using hot water. More importantly, the newly developed apparatus is 75% cheaper in costs and can more save energy than existing apparatus. These results indicate that the newly developed apparatus could serve as an effective apparatus for the oviposition induction of B. ignitus.

Lifespan elongation of Bombus terrestris and economic effect by regular pollen supplement to its hives released on beefsteak-tomato varieties.

About 50,000 hives of Bombus terrestris are used for pollination of tomato and other economical crops (fruit vegetables and fruit trees) in Korea. Therefore this study was conducted to find out the effective use of B. terrestris and its economic effect in the major beefsteak-tomato cultivation areas from February to August in 2008. The pollinating activities, rate of bite-mark and lifespan of B. terrestris`s hive according to all beefsteak-tomato varieties (Super Momotaro, Zeus42, Mascara and Super Sunroad, 500 , plants) were apparent by regular supplement of pollen (/3 days) to the hive of B. terrestris. Especially, Super Momotaro and Super Sunroad variety were most distinctive in the effects by regular pollen supplement.

Effect on the Pollinating Activities of Honeybee, Apis mellierfa L.(Hymenoptera: Apidae) and Bumblebee, Bombus terrestris L. in Paprika Vinyl-Houses

This study was surveyed the effects by pollinating activity of Apis mellifera and Bombus terrestris released in the paprika vinyl-houses. The foraging activity and behaviour of A. mellifera and B. terrestris visited on the paprika flowers were nearly alike. The pick times of pollinating activity by A. mellifera and B. terrestris were showed the hightest at 11:00 and 15:00, and 09:00 to 11:00, respectively. The rate of fruit set by A. mellifera and B. terrestris released for pollinating paprika were same level with 94%, and these rate were higher than the fruit setting rate which was 92% by fan operated. The qualities of paprika produced by pollinators released were higher than those by fan operated. And weight per fruit, number of seeds per fruit and economical profit per 2,310 were over 10% higher than those by fan operated. Therefore the economical effects by the pollinating activities of A. mellifera and B. terrestris released in the paprika vinyl-houses were obviously demonstrated.

Characteristics on the Pollinating Activity of Korean Native Bumblebee, Bombus ignitus Smith (Hymenoptera: Apidae) in the Peach House

The pollinating activity of bumblebee, Bombus ignitus was investigated at the blossom of Peach [Prunus persica (L.) Batsch] planted in vinyl house. The major time of foraging activity by B. ignitus was between 08:00 and 7:00, and the peak time of pollinating activity by B. ignitus was 11 :00 in the peach vinyl house from February 28 to March 5 in 2002. The rate of fruit set and the rate of marketable fruit by foraging activity of B. ignitus were much better than artificial pollination, and the effect of labor reduction by the pollinating activities of B. ignitus released against th e artificial pollination was took remarkable profits over 93%. Therefore, the foraging activity of B. ignitus in peach vinyl house brought satisfactory results among the rate of fruit set, the rate of marketable fruit and the effect of labor reduction against the artificial pollination.