• Title/Summary/Keyword: chemical controls

Search Result 280, Processing Time 0.029 seconds

Tolerance: An Ideal Co-Survival Crop Breeding System of Pest and Host in Nature with Reference to Maize

  • Kim, Soon-Kwon
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.45 no.1
    • /
    • pp.59-70
    • /
    • 2000
  • In nature, plant diseases, insects and parasites (hereafter called as "pest") must be co-survived. The most common expression of co-survival of a host crop to the pest can be tolerance. With tolerance, chemical uses can be minimized and it protects environment and sustains host productivity and the minimum pest survival. Tolerance can be applicable in all living organisms including crop plants, lifestocks and even human beings. Tolerant system controls pest about 90 to 95% (this pest control system often be called as horizontal or partial resistance), while the use of chemicals or selection of high resistance controls pest 100% (the most expression of this control system is vertical resistance or true resistance). Controlling or eliminating the pests by either chemicals or vertical resistance create new problems in nature and destroy the co-survial balance of pest and host. Controlling pests through tolerance can only permit co-survive of pests and hosts. Tolerance is durable and environmentally-friend. Crop cultivars based on tolerance system are different from those developed by genetically modified organism (GMO) system. The former stabilizes genetic balance of a pest and a host crop in nature while the latter destabilizes the genetic balance due to 100% control. For three decades, the author has implemented the tolerance system in breeding maize cultivars against various pests in both tropical and temperate environments. Parasitic weed Striga species known as the greatest biological problem in agriculture has even been controlled through this system. The final effect of the tolerance can be an integrated genetic pest management (IGPM) without any chemical uses and it makes co-survival of pests in nature.in nature.

  • PDF

Changes of Soil Properties in Corn (Zea mays L.) Fields Treated with Compost and Liquid Fertilizer (가축분뇨 퇴.액비가 시용된 옥수수 밭토양 특성 변화)

  • Kim, Min-Kyeong;Kwon, Soon-Ik;Kang, Seong-Soo;Jung, Goo-Bok;Kang, Kee-Kyung
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.44 no.3
    • /
    • pp.473-478
    • /
    • 2011
  • A wide diversity of liquid fertilizers and composts produced from the livestock manure in Korea is commonly applied to agricultural lands as an alternative of chemical fertilizers. However, their effects on the crop production and environmental impacts are still vague. The current study was conducted to understand the effects of the pig manure-based liquid fertilizer on the growth of Zea mays L. and soil properties. Four different liquid fertilizers were treated to each cultivated upland plot located in Gyeong-gi province, Korea while no fertilizer (control A) and a chemical fertilizer (control B) were treated to separate plots for comparison. The liquid fertilizer treatment did not make a significant difference in the fresh weight of Zea mays L. compared to the controls. This is probably due to the nutrient residues carried over from the last year fertilization. Electric conductivity (EC) and organic matter contents in soils were increased right after the liquid fertilizer treatments compared to the controls. However, soil pH was maintained as the same as the level of control A. A long-term effect of the continuous treatment of the manure based liquid fertilizer will be carried out in the successive study.

Determination of Free 4-hydroxyproline with Dansylchloride by HPLC in Human Urine (소변 중 4-hydroxyproline 분석에 관한 연구)

  • Lee, Keou-Weon;Cho, Young-Bong;Lee, Kyung-Jong
    • Journal of Preventive Medicine and Public Health
    • /
    • v.35 no.4
    • /
    • pp.282-286
    • /
    • 2002
  • Objectives : The level of 4-hydroxyproline (4-Hyp) in human urine was measured using high performance liquid chromatography (HPLC) with a fluorescence detector. This method is useful for medical examinations and investigating the radicals induced by physical, chemical, mental stresses. This method is superior to many published several methods in terms of its low cost and ability to analyze many samples. Methods : The urine from workers in a tire manufacturing company (22 male pre- and post-shift workers) and 18 office-workers as controls were analyzed. Data concerning age, the cumulative drinking amount and the cumulative smoking amount was collected with a questionnaire. The optimum applied amount of dansyl-Cl, the optimum reaction temperature and time, the recoveries and the optimum pH of the eluent and buffer were determined.4-Hyp from human urine was derivatized with dansyl-Cl (dimethylamino-naphthalene-1-sulfonyl chloride) after removing the a-amino acid by a treatment with phthalic dicarboxaldehyde (OPA) and cleaned with Bond Elut C18 column. The 4-Hyp derivatives were separated on a reversed phase column by gradient elution with a phosphate buffer (5 mmol, pH 8.0) and acetonitrile, and detected by fluorescence measurements at 340 nm (excitation) and 538 nm (emission). Results : The detection limit for the urinary free 4-Hyp was $0.364{\mu}mol/l$. The recovery rate of 4-Hyp was 99.7%, and the effective pH of the phosphate buffer and borate buffer were 3.0 and 8.0, respectively. From statistical analysis, age, drinking and smoking did not affect the urinary free 4-Hyp in both the controls and workers. The range of urinary 4-Hyp in the controls, pre-shift, and post-shift workers were 0.33-16.44, N.D-49.06, and $0.32-56.27{\mu}mol/l$. From the pared-sample t-test, the urinary 4-Hyp levels in post-shift workers ($11.82{\pm}6.73\;nmmol/mg\;Cre$) were 2-fold higher than in pre-shift workers ($5.36{\pm}5.53\;nmol;/mg\;Cre$) and controls ($4.91{\pm}4.89\;nmol;/mg\;Cre$). Conclusions : This method was developed with high sensitivity, accuracy, and precision. The present method was effectively applied to analyze the urinary free 4-Hyp in both controls and workers.

Physical and Chemical Evaluations of Refregerated Flatfish Treated with Organic Acids (유기산으로 처리한 냉장 광어의 이화학적 평가)

  • 김광현;김창렬
    • The Korean Journal of Food And Nutrition
    • /
    • v.11 no.3
    • /
    • pp.334-339
    • /
    • 1998
  • Flatfish strips were treated with 0.5%(v/v) acetic acid(AA), 0.5%(v/v) lactic acid(LA), or 0.5%(v/w) citric acid(CA) for 5 min. All strips were individually placed in Whirl-Pak sample bags and stored at 4 or 10$^{\circ}C$. pH, TBA, color, and sensory quality of strips were evaluated after 0, 3, 6, 9, and 12 days of storage time. The pH of samples treated with AA for 5 min ranged from 5.39 to 6.64 for 12 days at 4$^{\circ}C$, which had a significantly (P<0.05) lower level compared to the controls during storage time. Acid treatments had a significantly (P<0.05) higher levels of TBA values compared to the controls for 12 days at 4$^{\circ}C$. All acid treatments had lower Hunter a and b color scores compared to the controls. Acid treatments were liked less by sensory panels than the fresh control due to acidic odor and flesh discoloration.

  • PDF

Expression of CYP1A1 and GSTP1 in Human Brain Tumor Tissues in Pakistan

  • Wahid, Mussarat;Mahjabeen, Ishrat;Baig, Ruqia Mehmood;Kayani, Mahmood Akhtar
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.12
    • /
    • pp.7187-7191
    • /
    • 2013
  • Most of the exogenous and endogenous chemical compounds are metabolized by enzymes of xenobiotic processing pathways, including the phase I cytochrome p450 species. Carcinogens and their metabolites are generally detoxified by phase II enzymes like glutathione-S-transferases (GST). The balance of enzymes determines whether metabolic activation of pro-carcinogens or inactivation of carcinogens occurs. Under certain conditions, deregulated expression of xenobiotic enzymes may also convert endogenous substrates to metabolites that can facilitate DNA adduct formation and ultimately lead to cancer development. In this study, we aimed to test the association between deregulation of metabolizing genes and brain tumorigenesis. The expression profile of metabolizing genes CYP1A1 and GSTP1 was therefore studied in a cohort of 36 brain tumor patients and controls using Western blotting. In a second part of the study we analyzed protein expression of GSTs in the same study cohort by ELISA. CYP1A1 expression was found to be significantly high (p<0.001) in brain tumor as compared to the normal tissues, with ~4 fold (OR=4, 95%CI=0.43-37) increase in some cases. In contrast, the expression of GSTP1 was found to be significantly low in brain tumor tissues as compared to the controls (p<0.02). This down regulation was significantly higher (OR=0.05, 95%CI=0.006-0.51; p<0.007) in certain grades of lesions. Furthermore, GSTs levels were significantly down-regulated (p<0.014) in brain tumor patients compared to controls. Statistically significant decrease in GST levels was observed in the more advanced lesions (III-IV, p<0.005) as compared to the early tissue grades (I-II). Thus, altered expression of these xenobiotic metabolizing genes may be involved in brain tumor development in Pakistani population. Investigation of expression of these genes may provide information not only for the prediction of individual cancer risk but also for the prevention of cancer.

Effect of the Addition of Bovine Plasma on the Quality Properties of Steamed Fish Paste (우 혈장 첨가대체가 증자 어묵의 품질특성에 미치는 영향)

  • Yang, Cheul-Young
    • The Korean Journal of Food And Nutrition
    • /
    • v.21 no.4
    • /
    • pp.518-523
    • /
    • 2008
  • Experiments were conducted to assess the quality properties of steamed fish paste by addition level, along with a fish meat replacement(dried bovine plasma). The moisture, crude protein, crude fat and ash contents evidenced partially significant difference among the controls, DBP1, DBP2 and DBP3 groups(p<0.05). The pH values of the steamed samples were higher than those of the non-steamed samples, and when the content of the dried bovine plasma as meat replacement agent was increased, the pH was increased. The water holding capacity of the steamed fish past samples, along with the replacement levels were significantly higher than in the samples without the meat replacer(p<0.05). The range of cooking loss was $5.19{\sim}5.38%$. Structural weakening of the boiled samples was significantly higher than that observed in the fried sample. Hardness and chewiness were increased slightly by the addition of bovine plasma, but gel strength evidenced a pattern of decreased in DBP1, DBP2 and DBP3 groups. The result of our sensory evaluation on taste, texture, color and overall acceptance evidenced significant differences among the controls, DBP1, DBP2 and DBP3 groups, and the sensory score of color was the highest.

Influence of Occupational Exposure to Bisphenol A on the Sex Hormones of Male Epoxy Resin Painters

  • Cha, Bong-Suk;Koh, Sang-Baek;Park, Jun-Ho;Eom, Ae-Yong;Lee, Kang-Myeung;Choi, Hong-Soon
    • Molecular & Cellular Toxicology
    • /
    • v.4 no.3
    • /
    • pp.230-234
    • /
    • 2008
  • Epidemiological studies demonstrate an adverse effect of several environmental and occupational exposures on male sex hormone. Bisphenol A (BPA) is a weak estrogen and a widely used industrial chemical. Epoxy resin painters may be continuously exposed to BPA at high concentrations. The effect of occupational exposure of BPA on male reproduction was examined by measuring the urinary BPA, testosterone and gonadotropic hormones of epoxy resin painters in the shipyard. The painters had significantly higher concentrations of urinary BPA (2.61${\pm}$1.08 ${\mu}g$/g creatinine) than controls (1.38${\pm}$0.5 9 ${\mu}g$/g creatinine). In serum, the testosterone level of painters was significantly decreased but the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels of painters were significantly higher than controls. Occupational exposure to BPA influences testosterone and gonadotropic hormones in male workers.

Biocontrol Efficacy of Formulated Pseudomonas chlororaphis O6 against Plant Diseases and Root-Knot Nematodes

  • Nam, Hyo Song;Anderson, Anne J.;Kim, Young Cheol
    • The Plant Pathology Journal
    • /
    • v.34 no.3
    • /
    • pp.241-249
    • /
    • 2018
  • Commercial biocontrol of microbial plant diseases and plant pests, such as nematodes, requires field-effective formulations. The isolate Pseudomonas chlororaphis O6 is a Gram-negative bacterium that controls microbial plant pathogens both directly and indirectly. This bacterium also has nematocidal activity. In this study, we report on the efficacy of a wettable powder-type formulation of P. chlororaphis O6. Culturable bacteria in the formulated product were retained at above $1{\times}10^8$ colony forming units/g after storage of the powder at $25^{\circ}C$ for six months. Foliar application of the diluted formulated product controlled leaf blight and gray mold in tomato. The product also displayed preventative and curative controls for root-knot nematode (Meloidogyne spp.) in tomato. Under laboratory conditions and for commercially grown melon, the control was at levels comparable to that of a standard commercial chemical nematicide. The results indicated that the wettable powder formulation product of P. chlororaphis O6 can be used for control of plant microbial pathogens and root-knot nematodes.

The Effect of Rotating Magnetic Field on Enterotoxin Genes Expression in Staphylococcus Aureus Strains

  • Fijalkowski, Karol;Peitler, Dorota;Zywicka, Anna;Rakoczy, Rafal
    • Journal of Magnetics
    • /
    • v.21 no.1
    • /
    • pp.141-147
    • /
    • 2016
  • Staphylococcus aureus cultures exposed to rotating magnetic field (RMF) were studied in order to analyse the possible induced changes in staphylococcal enterotoxin genes (se) expression. Liquid cultures of S. aureus strains carrying different se were exposed to the RMF of magnetic frequency 50 Hz and magnetic induction 34 mT for 10 h at $37^{\circ}C$. Three time points of bacterial growth cycle were considered for RNA extractions. Gene expression analyses were evaluated using real-time quantitative PCR method. The present study confirmed, that the RMF can stimulate the growth rate of S. aureus cultures in comparison to the unexposed controls, while the stimulation is not strain dependent. The studies have also shown, that the RMF, depending on the exposure time but regardless the bacterial strain, can influence on the expression of various se. In general, except for sea, as a result of bacterial exposure to the RMF through subsequent growth phases, the expression of se decreased, reaching the values below results recorded for unexposed controls. In the case of sea expression remained at a lower level as compared to the control, regardless the time of exposition.

No Association of Cytochrome P450-1B1 Gene Polymorphisms with Risk of Breast Cancer: an Egyptian Study

  • Ibrahim, Mona H;Rashed, Reham A;Hassan, Naglaa M;Al-azhary, Nevin M;Salama, Asmaa I;Mostafa, Marwa N
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.6
    • /
    • pp.2861-2866
    • /
    • 2016
  • It is thought that population characteristics of breast cancer may be due to a variation in the frequency of different alleles of genes such as CYP1B1. We aimed to determine the association of CYP1B1 polymorphisms in 200 breast cancer cases and 40 controls by PCR-RFLP. Frequencies were assessed with clinical and risk factors in Egyptian patients. The genotype LV and the Leu allele frequencies for patients and controls were 42.9% and 50%, and 52.9% and 53.3%, respectively), with no significant differences observed (P values = 0.8 and 0.6, respectively). There was also no significant association between genotypes and any risk factors for cases (P>0.05) except laterality and metastasis of the tumor (P values=0.006 and 0.06, respectively). The CYP1B1 polymorphism Val432Leu was not associated with breast cancer in Egypt, but may provide clues for future studies into early detection of the disease.