During the survey of plant parasitic nematode of Citrus orchard in Korea, Paratrichodorus minor (Colbran, 1956) Siddiqi is founded from the soil of Citrus unshiu Markovich for the first time in Korea. The body length of females is 428.34~506.22 ㎛ long: a = 12.08~22.79, b = 4.02~5.02, V(%) = 38.46~60.68. The excretory pore is located near the base of esophagus. Additionally, the morphological characteristics on P. porosus (Allen, 1957) Siddiqi, 1974 recorded in 1976 on Korea is redescribed in detail.
This study was conducted to investigate occurrence and biodiversity of phytoparasitic nematodes in kiwifruit orchards in Korea. Soil samples were collected from 11 locations of Gosung, Goheung, Namhae, Bosung, Sacheon, Suncheon, Wando, Jangheung, Jeju, Jindo, Haenam from April to August, 2008.
Phytoparasitic nematodes were found in 115 among 178 soil samples.
The major genera of phytoparasitic nematodes on kiwifruit were Meloidogyne spp.(52.2%), Tylenchinae (42.1%), Tylenchus spp. (9.0%), Helicotylenchus spp. (9.0%) and Tylenchorhynchus spp. (6.7%). Ditylenchus spp., Hirschmaniella spp., Trichodorus spp. and Psilenchus spp. were also detected, even though their frequencies were very low. According to the cultivation period, the phytoparasitic nematodes were found as follows; 16.9% of soils under 5 years of kiwifruit cultivation, 10.7% 6~10 years, 23.0% 11~15 years, 3.9% 16~20 years and 5.6% over 21 years respectively. The frequency of phytoparasitic nematodes is higher in the open field (50.0%) than that in plastic houses (13.5%). The frequency of phytoparasitic nematodes was 36.5% in the field where vegetables were previously cultivated and 12.9% in the field where rice was previously cultivated.
Trophic groups and functional guilds were studied of soil nematodes from the soils of two abandoned mines in Ilkwang and Gunbuk, South Korea to compare nematode communities between the heavy metal contaminated soil and the nonheavy metal contaminated soil. No obvious correlation was found between the level of heavy metal and the total number of nematodes statistically. However the overall densities of bacterial, hyphal, omnivorous and predatory nematodes from the non-heavy metal contaminated soil was higher than those from the heavy metal contaminated soil. Also the densities of c-p 2, c-p 3, c-p 4 and c-p 5 nematodes were higher from the non-heavy metal contaminated soil than those from the heavy metal contaminated soil. MI, MI 2-5 and ΣMI 2-5 were higher, but there were no significant differences.
We amplified D1 and D3 expansion segments of the 28S ribosomal RNA from 10 Suanguina moxae populations found in Korea. The amplification of the D1-D3 expansion segments of 28S gene of all populations tested produced a single PCR product approximately 1.03kb in size, suggesting the lack of D1-D3 expansion region size polymorphism among populations. The secondary structure model of 28S expansion segments D2 and D3 for Subanguina Moxae was predicted based on free energy minimization with comparative sequence analysis and new sequence alignment was conducted based on predicted secondary structure model. The predicted model was compared with previous predicted models of plant and animal parasite nematode. This predicted secondary structure model will provide valuable information to allocate positional sequence homology and reconstruction of reliable phylogenetic trees.
Given the growing attention to nature and health in modern society, this study considered the role of a waterscape facility as a key element in a landscape’s influence on users’ physiological and psychological responses. The subjects were 28 university students, and the collected data included systolic and diastolic blood pressure, salivary amylase concentration, semantic differential (SD) scales, and profile of mood states (POMS). As compared to a space without any waterscape element (Type G), relaxation in a space with a waterscape element (Type W) was found to significantly reduce of systolic and diastolic blood pressure and salivary amylase concentration. The SD scale and POMS findings showed that Type W evoked active, bright, dynamic, free, vital, interesting, and cheerful images and improved mood states by enhancing vigor while inhibiting depressive feelings. These findings indicate waterscape facilities can improves users’ mood states and may enhance their health.