Small hive beetles (SHBs) are parasites of bee colonies and is one of the invasive pest species worldwide. In this study, we aimed to investigate a chemical responsible for the attractiveness of a hive to this pest. Based on the laboratory observation, we found the fermented pollen dough (honey bee food) was highly attractive to adult SHBs. Olfactometer bioassay showed the crude methanol extract of this material is attractive to both sexes (> 60%). However, the methanol extracts of fresh honey and pollen patty which we used as a food of SHB were not attractive to the pest. The crude methanol extract of fermented pollen dough was subjected to partitioning with n-hexane, chloroform, ethyl acetate, and n-butanol. The n-hexane and chloroform fractions were attractive > 80% for both sex SHBs. On the other hand, ethyl acetate and n-butanol were repulsive >70% and >80%, respectively. The wandering larvae of the pest showed a reverse response for the solvent fractions observed in adults. HPLC and GC-MS analysis indicated the methanol extract of fermented pollen dough constitute butanoic acid (7.70%), neopentylamine (7.29%), (E)-9-octadecenoic acid ethyl ester (3.89%) and hexadecanoic acid, ethyl ester. While these compounds were not found even in a trace level in the methanol extract of honey and pollen patty. Based on this findings these constituents of the fermented pollen dough were formed by the action of SHB and its larvae and we believe these volatile organic compounds are responsible for attractiveness to SHB as pollen dough undergoes attach by SHB and ferment. We are working on investigating attractiveness of each of these chemicals toward the pest. We recommend further work on these chemicals for their application to control this pest.

The potato tuber moth (PTM) is an oligophagous insect pest on solanaceous crops. Potato tuber is regarded as the main host of PTM but it can also feed, develop and reproduce on other solanaceous crops such as tomato. We tested adult olfactory behavior and larval development on 5 cultivated tomato varieties namely Money maker, Campari, Ailsa craig, LA 3475 (M82) and E-6203, and one wild species, S. pimpinellifolium. Tomato leaf hydro-distilled oils of Money maker, Campari, Ailsa craig, S. pimpinellifolium and E-6203 leaves showed strong attractiveness for mated adult PTM of both sexes (> 70%) in two-armed bioassay. LA 3475 (M82) oil showed repulsive response (83.7% for males and 87.3% for females). GC-MS analysis of the hydro-distilled oils of all tomato leaves contain the fatty acid n-hexadecanoic acid (Palmitic acid) as a major compound with relative percentage as S. pimpinelifollium (32.1%) > E-6203 (26.5%) > money maker (26.1%) > LA-3475 (16.3%) > Campari (15.0%) > Ailsa craig (10.4%). LA 3475 consists of (1-hexyltetraecyl)cyclohexane (10.5%) as the second major compound which was absent in all other tomato varieties. In no choice test, PTM larvae showed highest developmental performances such as number of mines, headcapsule size, pupal weight and survival in Ailsa craig, and lowest in LA 3475. In choice test, similar results were observed. This study indicates the leaf volatile of n-hexadecanoic acid might be responsible for PTM attractiveness and (1-hexyltetraecyl)cyclohexane for repulsiveness. And varieties of tomato leaves could support suitable nutritional contents to PTM, posing pest potential in the future where higher exposure is expected.

The correlation analysis between odor sensor and air dilution olfactometry method with odor emission facilities was performed for the real-time evaluation of odor emitted from the 13 facilities. The total correlation was less significant for all facilities due to various emission characteristics of odor. The correlation for the individual facility, however, showed a higher correlation coefficient (R=0.7371~0.9897). Especially, the strong correlation (above 0.9) was observed for the industry type with the odor characteristics like tobacco, styrofoam, acetic acid, and burning smell. The repeated odor measurements using the odor sensor showed good reproducibility with the mean relative standard deviation of 5.06%. The odor sensor could be useful tools for identifying and evaluating odor with an olfactometry in field, if the use and proofreading of the odor sensor are improved by a standardized method.