Evaluation of waterlogging tolerance with the degree of foliar senescence at early vegetative stage of maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.)

Maize is highly susceptible to waterlogging, which is becoming one of worldwide abiotic threats in many agricultural areas. This study was evaluated to establish the screening method and to find tolerant maize genotypes. Six Korean maize inbred lines were subjected to waterlogging at V3 for 15 days using a big size pot with single maize plant (big pot method) and a box containing 31 maize plants at a time (box method). The degree of foliar senescence and the number of senescent leaves were better indicators for selecting waterlogging tolerant maize genotypes than SPAD value and plant height. The degree of foliar senescence revealed that KS124, KS140, and KS141 are tolerant, and KS85 is susceptible to waterlogging at the early growth stage. These responses of foliar senescence were in clear accordance with those of plant grain yield, which was supported by stress tolerance index for grain yield. The box method also showed the similar response of foliar senescence to the big pot method. Therefore, this box method based on foliar senescence may be simple and efficient for large-scale screening of maize germplasm against waterlogging stress. It was concluded that foliar senescence can be a good indicator for selecting tolerant maize genotypes against waterlogging at the early growth stage.     

Functional rice cultivars goami and nokwon may lower body weight and improve lipid metabolism in high fat-fed mice cultivars

The demand for functional foods is rapidly increasing due to the rising prevalence of metabolic diseases, particularly obesity and hyperlipidemia. In the few past years, various rice cultivars with enhanced functional quality and health-promoting properties have been produced. Functional rice Goami (high-amylose rice) and Nokwon (green-kerneled rice) have recently been developed, but little is known about their physiological activity. Hence, this study was conducted to determine the effect of functional rice on the body weight and lipid metabolism in mice under high-fat diet conditions. Forty male C57BL/6N mice were randomly divided and fed with experimental diets for 8 weeks: normal control (NC), high fat (HF), and high fat supplemented with white rice (HF-WR), Goami rice (HF-GR), and Nokwon rice (HF-NR). At the end of the experimental period, a marked increase in the body weight, plasma triglyceride level, and total cholesterol concentrations were found in the HF mice relative to the NC group. However, diet supplementation of Goami and Nokwon improved the lipid profile in mice through regulation of lipogenesis and adipokine production. These findings illustrate that the new functional rice cultivars Goami and Nokwon may be useful as biomaterials in the development of functional food for the prevention and treatment of high-fat, diet-induced hyperlipidemia and obesity.     

Natal dispersal of hazel grouse Bonasa bonasia in relation to habitat in a temperate forest of South Korea

Natal dispersal and habitat selection of hazel grouse Bonasa bonasia juveniles were assessed by radio tracking in a temperate forest of South Korea during June 2003–November 2006. The birds used in the dispersal analysis (n = 43), 88% of birds dispersed. The average dispersal of hazel grouse from the natal area was 2231 ± 494 m (mean ± SD); range 134–6267 m. There were no significant differences in dispersal rate and distance between sexes. Hazel grouse’ habitat use differed from random use of available natal dispersals. In this natal dispersal scale of habitat selection, natural deciduous forest ranked highest, followed by mixed forest, coniferous plantation, deciduous plantation and others (rock and bare lands). We found that in general, the hazel grouse is an active disperser. Knowledge of aspects of habitat use that are relevant to dispersal may provide a better assessment of the fitness effects of dispersal in proximate and ultimate terms.     

Laboratory and Field Assessment of the Decagon 5TE and GS3 Sensors for Estimating Soil Water Content in Saline-Alkali Reclaimed Soils

The objective of this study was to assess, under laboratory and field conditions, the performance of the Decagon 5TE and GS3 soil water sensors in estimating the soil water content of saline-alkali reclaimed land in South Korea. The error due to increased bulk soil EC was greater for the 5TE sensor than for the GS3 sensor and was greater in soil with higher bulk soil EC. Therefore, it is recommended that the soil electrical conductivity be considered in the calibration process for the 5TE. The calibration equations developed for the 5TE and GS3 sensors during laboratory experiments were highly accurate. Testing of the 5TE and GS3 sensors showed very good agreement between actual VWC and VWC calculations resulting from the field-derived calibration. These results suggest that either sensor can be used to acquire accurate soil water content data in the field.     

Reclamation of a coastal reclaimed tidal land soil by gypsum and rice straw

This study was to evaluate the application effect of gypsum and rice straw on the saline–sodic soils of coastal reclaimed tidal lands during newly reclamation process by leaching method. Soil used in the lysimeter experiment is classified as Greyic Hydragric Anthrosols (Sodic Arenic). The experiment was carried out over a period of 1 year from May 2014 to July 2015 inside a plastic film house. Saturated electrical conductivity (EC_e) and exchangeable sodium percentage (ESP) values of soils in gypsum treatment and gypsum with rice straw treatment then reached the desalinization criteria (EC_e = 4.0 dS m^?1, ESP = 15%) after the five or six pore volumes leaching cycles. However, in spite the 10 pore volumes leaching cycles in control and rice straw alone treatment, the values did not reach the desalinization criteria. The results showed that effectiveness of improvement of sodicity and salinity in coastal reclaimed tidal land soils was in the order of gypsum = gypsum + rice straw > rice straw = control. Our study has shown that gypsum alone treatment or gypsum with rice straw treatment in a coastal reclaimed tidal land soils improves their physicochemical characteristics.     

The Effects of Omega-3 Fatty Acid on Vitamin D Activation in Hemodialysis Patients: A Pilot Study

The high incidence of cardiovascular disease and vitamin D deficiency in chronic kidney disease patients is well known. Vitamin D activation by omega-3 fatty acid (FA) supplementation may explain the cardioprotective effects exerted by omega-3 FA. We hypothesized that omega-3 FA and 25-hydroxyvitamin D (25(OH)D) supplementation may increase 1,25-dihydroxyvitamin D (1,25(OH)₂D) levels compared to 25(OH)D supplementation alone in hemodialysis (HD) patients that have insufficient or deficient 25(OH)D levels. We enrolled patients that were treated for at least six months with 25(OH)D < 30 ng/mL ({"type":"clinical-trial","attrs":{"text":"NCT01596842","term_id":"NCT01596842"}}NCT01596842). Patients were randomized to treatment for 12 weeks with cholecalciferol supplemented with omega-3 FA or a placebo. Levels of 25(OH)D and 1,25(OH)₂D were measured after 12 weeks. The erythrocyte membrane FA contents were also measured. Levels of 25(OH)D were increased in both groups at 12 weeks compared to baseline. The 1,25(OH)₂D levels at 12 weeks compared to baseline showed a tendency to increase in the omega-3 FA group. The oleic acid and monounsaturated FA content decreased, while the omega-3 index increased in the omega-3 FA group. Omega-3 FA supplementation may be partly associated with vitamin D activation, although increased 25(OH)D levels caused by short-term cholecalciferol supplementation were not associated with vitamin D activation in HD patients.     

Involvement of the Fas and Fas ligand in testicular germ cell apoptosis by zearalenone in rat

Zearalenone (ZEA), a nonsteroidal estrogenic mycotoxin, is known to cause testicular toxicity in animals. In the present study, the effects of ZEA on spermatogenesis and possible mechanisms involved in germ cell injury were examined in rats. Ten-week-old Sprague-Dawley rats were treated with 5 mg/kg i.p. of ZEA and euthanized 3, 6, 12, 24 or 48 h after treatment. Histopathologically, spermatogonia and spermatocytes were found to be affected selectively. They were TUNEL-positive and found to be primarily in spermatogenic stages I-VI tubules from 6 h after dosing, increasing gradually until 12 h and then gradually decreasing. Western blot analysis revealed an increase in Fas and Fas ligand (Fas-L) protein levels in the ZEA-treated rats. However, the estrogen receptor (ER)α expression was not changed during the study. Collectively, our data suggest that acute exposure of ZEA induces apoptosis in germ cells of male rats and that this toxicity of ZEA is partially mediated through modulation of Fas and Fas-L systems, though ERα may not play a significant role.     

MPN-PCR enumeration of <Emphasis Type="Italic">Campylobacter</Emphasis> spp. in raw chicken meats and by-products

The goal of this study is to enumerate Campylobacter in chicken meats and by-products. In the current investigation, results showed that raw chicken meats and chicken by-products were contaminated with Campylobacter ranging from <3 to 4600 MPN·g⁻¹. Campylobacter jejuni showed a higher number compared to Campylobacter coli in the chicken samples. The current study showed that the percentage of chicken livers and gizzards harbored a higher number of Campylobacter (10³–10⁴ MPN·g⁻¹) than other chicken parts at 33.3% and 9.2%, respectively. The different concentrations of Campylobacter between chicken meats and chicken byproducts reflect the differences in the contamination level. The data on Campylobacter concentration in chicken meats and by-products will be useful in risk analysis.