실내 벽면녹화용으로 많이 이용되고 있는 덩굴식물 스킨답 서스(Epipremnum aureum)는 줄기의 상·하 유인방향에 생장 차이를 보이는 것으로 알려져 있으나 그 원인에 대해서는 구 체적으로 알려져 있지 않다. 본 연구에서는 광원의 위치(상· 하)와 줄기 유인방향(상·하)에 따른 스킨답서스의 생장반응을 15주간 조사하였다. 그 결과 정상적인 식물 생장 환경조건인 광원이 위에 있고 줄기를 위로 유인한 처리를 제외하고는 광 원이 아래에 위치하거나 줄기를 아래로 유인한 처리에서는 굴 곡과 뒤틀림 정도가 매우 컸다. 이것은 굴광성과 항굴지성에 대한 식물체 지상부의 반응 결과이며, 굴광성과 항굴지성의 경합반응은 식물체 아래 광원이 위치하고 줄기를 아래로 유인 했을 때 더욱 뚜렷하였다. 광원의 위치와 줄기 유인방향에 따 른 스킨답서스의 생장 반응은 굴광성과 항굴지성으로 설명 가 능하며 굴광성의 영향이 상대적으로 높게 나타났다.
Temperature and insecticide are two important factors that affect survival, reproduction and other physiological processes of insects. To determine interactions of temperature and insecticide treatment on susceptible (S) and imidacloprid-resistant strains (IMI-R) of Aphis gossypii, adults were exposed to three temperatures (17, 22, and 28℃) or combinations of three temperatures (17, 22 and 28℃) and imidacloprid (LC20), and the expression of several genes (heat shock protein 70, cuticle protein, cytochrome P450, and elongation factor) were analyzed. The expression level at 17℃ of heat shock protein 70, cuticle protein, and elongation factor in S strain were up-regulated with increased time and higher than those of IMI-R strain. However, expression of cytochrome P450 was not affected by elevated temperature both S and IMI-R strain. Combined treatment of elevated temperature and imidacloprid were significantly up-regulated only cuticle protein in S strain and higher than those of IMI-R strain.
The effect of increased carbon dioxide concentration in atmosphere was examined on the pheromone system of Helicoverpa armigera reared from egg stage to adult in three room. Two of three room (2×2×2 m) were treated with carbon dioxide gas as 600 ppm and 1,000 ppm, respectively. Mean of carbon dioxide concentration was 429.1 ppm in the control, 603.3 ppm for 600 ppm, and 1011.5 ppm for 1,000 ppm during experiment. Electroantenograph (EAG) test was conducted on 3-d-old male adults with air, hexane, and a series of their sex pheromone component, Z11-16Al, from 0.01 to 100 ng. The result was that male EAG responses of 600 and 1,000 ppm were 30.3% lower than that of control room. Production of Z11-16:Al was examined on about twenty 2-d-old virgin females. Carbon dioxide increases did not show a statistically significant difference. However, higher amount of sex pheromone was produced in females of 600 and 1,000 ppm. So, This experiment was replicated with different population reared again. The amount of the sex pheromone per female was 108.9 and 118.1 ng in control room, 139.8 and 141.8 ng in 600 ppm room, and 124.6 and 125.8 ng in 1,000 ppm room.
Apple and pear are popular fruits consumed in Korea and are common fruit in daily diet. In order to compare the antioxidant activity of the apple and pear peels, total polyphenol contents, total flavonoid contents, ABTS+ free radical scavenging activity, and DPPH free radical scavenging activity were measured from hot water, ethanol, and methanol extracts of the two fruit peels. The total polyphenol and flavonoid contents were highest in 95% methanol extracts of the apple peelsand 70% ethanol extract of the pear peels, respectively. Total polyphenol contents of the pear peels were higher than that of apple peels, and total flavonoid contents of the apple peels were higher than that of pear peels. The apple and pear peels had the highest ABTS+· and DPPH free radical scavenging activity in 95% methanol extracts and 70% ethanol extracts, respectively. ABTS+· and DPPH free radical scavenging activity of pear peels was higher than that of apple peels, and the DPPH free radical scavenging activity of apple and pear peels were detected in hot water, 95% methanol, and 70% ethanol extracts, respectively. Ascorbic acid, a synthetic antioxidant used as positive control, had significantly higher scavenging activity than the apple and pear peels. In conclusion, the apple and pear peelshave great potential as natural antioxidants. Therefore, above results should be considered to provide the possibility for the development of high functional antioxidants.