• Title/Summary/Keyword: Growth and survival rates

Search Result 387, Processing Time 0.028 seconds

Tolerance of Corn, Sorghum, Sorghum-Sudangrass Hybrid, and Pearl Millet to Simazine and Alachlor (옥수수, 수수, 수수-수단그라스 교잡종 및 진주조의 Simazine과 Alachlor에 대한 저항성)

  • 이석순;최상집
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.34 no.2
    • /
    • pp.113-119
    • /
    • 1989
  • In 1988 the tolerance of corn, sorghum, sorghum-sudangrass. and pearl millet hybrids to simazine and alachlor was tested in field during the growing season and pots during the summer and fall. In field and summer pot experiments(Exp.) the above mentioned four crops were tested at the ratios of simazine WP (50% ai, g/10a) ; alachlor EC (43.7% ai. ml/10a) of 130: 0, 100: 0, 70: 200, 0: 300 and 0: 400 and a sorghum hybrid was tested at 0, 50, 100, 200, 300, and 400ml/10a of alachlor and 70g/10a of simazine+ 200ml/10a of alachlor in fall pot Exp. In corn emergence rate, percent stand, plant height of seedlings, and dry matter(DM) yield were not affected by simazine and alachlor in all Exps. In sorghum and sorghum-sudangrass early growth and DM yield were not affected by simazine and alachlor in field Exp. In contrast, simazine reduced height and dry weight of seedlings slightly without any deterimental effects on emergence and survival rates. but alachlor reduced survival rate, plant height, and dry weight of seedlings significantly in summer pot Exp. In fall Exp. alachlor did not affect emergence rate of a sorghum hybrid, but survival rate, plant height, and dry weight of seedlings reduced with increased levels of alachlor when applied higher than 100ml/10a. In pearl millet simazine did not affect emergence rate, plant height, and DM yield in field, but reduced survival rate, plant height, and dry weight of seedlings in summer pot Exp. However, alachlor reduced DM yield significantly due to a lower percent stand even in the field. In summer pot Exp. although emeregence rate was slightly reduced, all seedlings were dead after emergence. Simazine did not control grasses such as Digitaria sanguinalis, Setaria viridis, Echinochloa crusgalli effectively, but controlled broadleaf weeds. Alachlor controlled all grasses, Porluraca oleracea, and Amaranthus mangostanus, but did not control Acalypha australis and Chenopodium album. A combination of simazine and alachlor controlled weeds more effectively than either simazine or alachlor alone.

  • PDF

High frequency direct plant regeneration from leaf, internode, and root segments of Eastern Cottonwood (Populus deltoides)

  • Yadav, Rakesh;Arora, Pooja;Kumar, Dharmendar;Katyal, Dinesh;Dilbaghi, Neeraj;Chaudhury, Ashok
    • Plant Biotechnology Reports
    • /
    • v.3 no.3
    • /
    • pp.175-182
    • /
    • 2009
  • Simple, reproducible, high frequency, improved plant regeneration protocol in Eastern Cottonwood (Populus deltoides) clones, WIMCO199 and L34, has been reported. Initially, aseptic cultures established from axillary buds of nodal segments from mature plus trees on MS liquid medium supplemented with $0.25mg\;1^{-1}$ KIN and $0.25mg\;1^{-1}$ IAA. Nodal and internodal segments were found to be extra-prolific over shoot apices during course of aseptic culture establishment, while $0.25mg\;1^{-1}$ KIN concentration played a stimulatory role in high frequency plant regeneration. Diverse explants, such as various leaf segments, internodes, and roots from in vitro raised cultures, were employed. Direct plant regeneration was at high frequency of 92% in internodes, 88% in leaf segments, and 43% in root segments. This led to the formation of multiple shoot clusters on established culture media with rapid proliferation rates. Many-fold enhanced shoot elongation and growth of the clusters could be achieved on liquid MS medium supplemented with borosilicate glass beads, which offer physical support for proliferating shoots leading to faster growth in comparison to semi-solid agar or direct liquid medium. SEM examination of initial cultures confirmed direct plant regeneration events without intervening calli. In vitro regenerated plants induced roots on half-strength MS medium with $0.15mg\;1^{-1}$ IAA. Rooted 5- to 6-week-old in vitro regenerated plants were transferred into a transgenic greenhouse in pots containing 1:1 mixture of vermicompost and soil at $27{\pm}2^{\circ}C$ for hardening and acclimatization. 14- to 15-week-old well-established hardened plants were transplanted to the field and grown to maturity. The mature in vitro raised poplar trees exhibited a high survival rate of 85%; 4-year-old healthy trees attained an average height of 8 m and an average trunk diameter of 25 cm and have performed well under field conditions. The regeneration protocol presented here will be very useful for undertaking genetic manipulation, providing a value addition to Eastern Cottonwood propagation in future.

Improving Corsican pine somatic embryo maturation: comparison of somatic and zygotic embryo morphology and germination

  • Wtpsk, Senarath;Shaw, D.S.;Lee, Kui-Jae;Lee, Wang-Hyu
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2003.04a
    • /
    • pp.61-62
    • /
    • 2003
  • Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

  • PDF

Dietary value of rotifer fed on the different diets in high density culture for flounder larvae, Paralichthys olivaceus (넙치 자어 사육에 있어서 먹이 종류에 따라 고밀도로 배양한 rotifer의 먹이효율)

  • PARK Huem Gi;LEE Kyun Woo;LEE Sang-Min;KIM Sung Koo;LEE Jong Ha;LIM Young Soo
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.33 no.2
    • /
    • pp.93-97
    • /
    • 2000
  • This study was carried out to investigate the effect of rotifer fed the different diets in high density culture on larval flounder Paralichthys olivaceus. Potifer was enriched with enrichment supplements, Marine ${\alpha}\;and\;{\omega}-yeast$ for 6 hours after being cultured with freshwater Chlorella for 18 hours during high density culture before it was fed to larval flounder. And rotifer was culutured with marine Chlorella and freshwater Chlorella for 24 hours during semi-continuous high density culture before it was fed to larval flounder. Culture tanks(21 working volum) set for rotifer culture in a water bath($28{\circ}C$) were continuously supplied with oxygen gas. The content of n-3 HUFA to fatty acids in rotifer(dry weight ${\%}$) enriched with Marine ${\alpha}$ for 6 hours and cultures with marine Chlorella for 24 hours were higher than that in rotifer enriched with ${\omega}-yeast$ for 6 hours or cultured with freshwater Chlorella for 24 hours. The growth and survival rates of larval flounder fed on rotifer enriched with Marine ${\alpha}$ for 6 hours and cultured with marine Chlorella for 24 hours were higher than those of larval flounder fed on rotifer enriched with ${\omega}-yeast$ for 6 hours or cultured with freshwater Chlorella for 24 hours. And the content of n-3 HUFA of larval flounder fed on rotifer enriched with Marine ${\alpha}$ for 6 hours was higher than that of larval flounder fed on other rotifers, The results from this study indicated that rotifer culture with marine Chiorelia would be suitable for the high density culture and effective diet for the growth of larval flounder.

  • PDF

Studies on Seed Production of Rainbow Trout, Oncorhynchus mykiss - Hatching rate and early stage performance of USA strain rainbow trout, Oncorhynchus mykiss - (무지개송어, Oncorhynchus mykiss의 종묘생산에 관한 연구 - 미국산 무지개송어의 부화 및 자치어 성장 -)

  • Baik, Kook-Ki;Choi, Young-Hee;Lee, Joong-Chul;Park, In-Sik;Kim, Young-Kil;Kim, Doo-Youn;Lee, Chae-Sung
    • Journal of Aquaculture
    • /
    • v.20 no.2
    • /
    • pp.85-89
    • /
    • 2007
  • This study examined the hatching rate of eyed-eggs and growth of fingerlings of USA strain rainbow trout, Oncorhynchus mykiss, which were transplanted on Nov. 17, 2005 from the USA for improvement of breeding. The diameter and weight of eyed-eggs were $4.95{\pm}0.34\;mm$ and $0.07{\pm}0.003\;g$, respectively. The eyed-eggs were hatched in 8 days later and hatching rates were $77.3{\sim}98.6%$. After 56 days from hatching, the fingerlings grew to $4.0{\pm}0.7$ cm and 0.62 g in total length and body weight, respectively. The relationships between total length (TL) and elapsed days (ED) were expressed as TL=0.0366ED+1.8645 ($r^2=0.928$, n=350). The relationships between body weight (BW) and elapsed days (ED) were expressed as following; $BW=0.0638e^{0.0408ED}\;(r^2=0.9917,\;n=350)$. And survival of rainbow trout was $64.5{\pm}1.3%$ in 56 days after hatching.

Predictive Factors for Switched EGFR-TKI Retreatment in Patients with EGFR-Mutant Non-Small Cell Lung Cancer

  • Kwon, Byoung Soo;Park, Ji Hyun;Kim, Woo Sung;Song, Joon Seon;Choi, Chang-Min;Rho, Jin Kyung;Lee, Jae Cheol
    • Tuberculosis and Respiratory Diseases
    • /
    • v.80 no.2
    • /
    • pp.187-193
    • /
    • 2017
  • Background: Third-generation tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR-TKIs) have proved efficacious in treating non-small cell lung cancer (NSCLC) patients with acquired resistance resulting from the T790M mutation. However, since almost 50% patients with the acquired resistance do not harbor the T790M mutation, retreatment with first- or second-generation EGFR-TKIs may be a more viable therapeutic option. Here, we identified positive response predictors to retreatment, in patients who switched to a different EGFR-TKI, following initial treatment failure. Methods: This study retrospectively reviewed the medical records of 42 NSCLC patients with EGFR mutations, whose cancers had progressed following initial treatment with gefitinib or erlotinib, and who had switched to a different first-generation EGFR-TKI during subsequent retreatment. To identify high response rate predictors in the changed EGFR-TKI retreatment, we analyzed the relationship between clinical and demographic parameters, and positive clinical outcomes, following retreatment with EGFR-TKI. Results: Overall, 30 (71.4%) patients received gefitinib and 12 (28.6%) patients received erlotinib as their first EGFR-TKI treatment. Following retreatment with a different EGFR-TKI, the overall response and disease control rates were 21.4% and 64.3%, respectively. There was no significant association between their overall responses. The median progression-free survival (PFS) after retreatment was 2.0 months. However, PFS was significantly longer in patients whose time to progression was ${\geq}10months$ following initial EGFR-TKI treatment, who had a mutation of exon 19, or whose treatment interval was <90 days. Conclusion: In patients with acquired resistance to initial EGFR-TKI therapy, switched EGFR-TKI retreatment may be a salvage therapy for individuals possessing positive retreatment response predictors.

Effects of Suhwagije-tang Distillate on Serum and Testosterone in Aging Rats (수화기제탕(水火旣濟湯)이 주령별 흰쥐의 혈청과 테스토스테론에 미치는 영향)

  • Lee, Jung-Hwan;Goo, Deok-Mo;Ahn, Taek-Won
    • Journal of Sasang Constitutional Medicine
    • /
    • v.22 no.4
    • /
    • pp.85-97
    • /
    • 2010
  • 1. Objectives The purpose of this study is to investigate the effects of oral administration of distilled Suhwagije-tang in aging rats. 2. Methods The SD rats used in this experiment were 6, 48 and 68 weeks old. These groups were treated with distilled water(DW), 1% Vitamin C(Vit. C) and 50% Suhwagije-tang(SGT) distillate respectively, once a day for 4 weeks. Blood samples were taken from heart and the levels of various parameters in serum were analysed. 3. Results and Conclusions (1) At all concentration of SGT, survival rates of liver cells were higher than the control group. (2) The rate of which the 10W-SGT group gained weight was significantly higher than that of the control groups. (3) The levels of albumin in serum of 10W-SGT group were significantly increased in comparison to those of the DW group. The levels of ALP, total cholesterol and HDL-cholesterol in serum of 52W-SGT group were significantly decreased in comparison to those of the DW group. (4) The levels of testosterone in serum of SGT groups showed no significantly changes in comparison to those of the control groups. Testosterone levels were naturally decreased with advancing years, so 72W-DW group's testosterone level was significantly decreased in comparison to those of 10W-DW group's. In contrast, 72W-SGT group's level was the highest in comparison to those of the control groups and those of deviation from 10W, 52W and 72W in SGT groups was also smaller than control groups'. (5) The levels of glucose, total-bilirubin, ALT, AST, BUN, CRP, hs-CRP, homocystein, Na, K, Na/K ratio, Cl and Ca in serum of SGT groups showed no significantly changes in comparison to those of the control groups. These results suggest that oral administration of Suhwagije-tang distillate should be effective in promoting growth and preventing rapid decline of testosterone in aging rats does not cause any imbalance in liver, kidney and electrolyte.

Effect of Exogenous Trehalose on the Solvent Tolerance of Pseudomonas sp. BCNU 106 (유기용매 내성 Pseudomonas sp. BCNU 106 균주의 외인성 트레할로스의 영향)

  • Choi, Hye Jung;Lim, Bo Ra;Ha, Sang-Chul;Kwon, Gi-Seok;Kim, Dong Wan;Joo, Woo Hong
    • Journal of Life Science
    • /
    • v.27 no.8
    • /
    • pp.945-950
    • /
    • 2017
  • To some extent, the growth of solvent-tolerant Pseudomonas sp. BCNU 106 is limited by toxic solvents. Therefore, various strategies to overcome this limitation need to be investigated. One such strategy is to use exogenous trehalose. The highest intracellular trehalose content of 181.88 mM was measured at 12 hr. The extracellular trehalose content decreased rapidly within 12 to 16 hr in the presence of cyclohexane. Moreover, the number of Pseudomonas sp. BCNU 106 cells grown in Luria-Bertani (LB) broth supplemented with 0.1 M trehalose in the presence of 1%(v/v) cyclohexane, hexane, propylbenzene, and m-xylene increased 89.94-, 89.72-, 91.25-, and 118.9-fold, respectively, in comparison to the control level. High survival rates of 80% and 90% were observed in the presence of cyclohexane and hexane by the addition of 0.05 M trehalose for up to 4 hr, respectively. Exogenously-added trehalose was transported into the cells, and it conferred protection against cyclohexane, hexane, propylbenzene, and m-xylene. Adding exogenous trehalose to the growth medium improved the tolerance of Pseudomonas sp. BCNU 106; thus, it is a potential biocatalyst for biotransformation and biodegradation.

A Study on the Cytotoxic Activity of Garlic(Allium Sativum) Extract Against Cancer Cells (마늘중 지용성 성분의 암세포증식 억제효과 연구)

  • 손흥수
    • Journal of Nutrition and Health
    • /
    • v.23 no.2
    • /
    • pp.135-147
    • /
    • 1990
  • This study was devised to observe the cytotoxic activities of garlic extracts against various cancer cells, that is, murine leukemic lymphocyte(L1210 and P388) and human rectal(HRT-18) and colon cancer cells(HCT-48 and HT-29) in vitro, and murine ascitic tumor cell(S-180) in vivo. Each cell-line except S-180 was cultured in medium containing serial concentration of the garlic extract in vitro. Inhibitory effect n the growth rate of the cancer cells was stronger in extracts of petroleum ether than that of ethanol. A lipid soluble compound in the extracts of garlic was cytocidal to murine leukemic cells, human rectal and colon cancer cells in vitro. The growth rates of the cancer cells in medium containing garlic extracts were inhibited gradually to a significant degree in proportion to the increase of the extract concentration. The cytotoxic activity of garlic active fraction from TLC was about 2.3 times more potent than that of crude garlic extract, one unit of cytotoxic activity against L1210 cells being equivalent to 4.2$\mu\textrm{g}$ and 1.8$\mu\textrm{g}$ from the crude garlic and active fraction, respectively. The Rf value of the active fraction on silica-gel TLC was 0.18 in condition that petroleum ether/ethyl ether/acetic acid mixture(90:10:1, v/v/v) was used as a developing solvent. The survival times of mice inoculated with S-180 cells were extended about 1.5 to 2 times in the groups treated with garlic extract(through i.p. and oral administration) compared with their control group(no garlic extract treatment). Observations were carried out on S-180. Ethanol extracts of garlic injured markedly tumor cells within 3 hours after injection.

  • PDF

Gamma-ray Irradiation on Radio Sensitivity in Yacon (Samallanthus sonchifolius (Poepp. & Endl.) H. Robinson) Breeding (돌연변이 육종을 위한 야콘의 최적 감마선 조사량)

  • Su Jeong Kim;Hwang Bae Sohn;Yul Ho Kim;Jung Hwan Nam;Jong Nam Lee;Dong Chil Chang;Jong Taek Suh
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2021.04a
    • /
    • pp.27-27
    • /
    • 2021
  • Yacon [Samallanthus sonchifolius (Poepp. & Endl.) H. Robinson], a member of Compositae plants, has sweet taste and crisp texture. Unlike other Andean root crops such as potato and sweet potato, the cultivation area of yacon has increased recently, since it is known to have large content of fructooligosaccharides (FOS). Since there are no yacon varieties bred in Korea, we have been trying to create new genetic resources using gamma-ray. The optimal gamma-ray dosage for mutation breeding in yacon was investigated. Crown bud and green bud of yacon were exposed to doses of gamma rays from 20 Gy to 80 Gy, and subsequently planted in a greenhouse. After 50 days of sowing, the survival rates and growth decreased rapidly at doses above 40 Gy, while all of crown bud individuals died above 60 Gy. The median lethal dose (LD50) of crown bud and green bud was 22.4 and 36.6 Gy, and the median reduction doses (RD50) for plant height, fresh weights, and tuberous root weight were 20-40 Gy, respectively. A dose of 20-40 Gy was found to be optimal for mutation breeding in yacon. Considering the growth factors, the optimum doses were determined to be within the range of 20-40 Gy for the selection of useful mutant lines. M2-M3 mutant lines were obtained from 20-60 Gy gamma-ray-irradiated M1 plants through clonal propagation. These mutant lines will be used for the development of a new variety of yacon plant with high FOS and no crack tuberous root.

  • PDF