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Softshell turtle (Trionyx sinensis Wiegmann) hatchlings were reared at 28 ± 2°C in the laboratory to test the effect of the presence of a sand substrate. The growth and survival of the hatchlings were monitored for a period of 14 weeks. The presence of the sand substrte significantly enhanced the growth of the hatchlings. Survival of the hatchlings, however, was independent of the presence of the sand substrate. 相似文献
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Grain yields of seven barley cultivars (Hordeum vulgare L.) and 398 doubled-haploid lines derived from their diallel crosses were evaluated in hill plots at two locations in Ontario. Additive × additive epistasis and linkage disequilibrium were detected in the seven cultivars. Additive × additive genetic variance was significantly greater than zero but additive genetic variance was not significantly greater than zero. The narrow-sense heritability on the basis of line means was intermediate (0.33). It was predicted that 13.1% yield improvement could be realized in the next recurrent selection cycle using the doubled-haploid method. 相似文献
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The genetics of resistance to Septoria speckled leaf blotch (SSLB), caused by Septoria passerinii, was studied in the Leger × CIho9831 barley doubled-haploid population. The 140 lines in the population segregated as 102 resistant and 38 susceptible, approximating a 3:1 ratio. A recombination map was developed using diversity arrays technology and other molecular markers. Quantitative trait locus (QTL) analysis demonstrated that resistance is primarily conferred either by having the CIho9831 allele at a QTL on 6HS or by having the CIho9831 allele at both of two QTLs on 3H and 2HL. In addition, ≈1/16 of the lines were resistant for unidentified reasons. This model predicts a resistant/susceptible ratio of 11:5, which fits the phenotypic observations. Minor QTLs were detected on 2HS and 1H. DNA sequences of linked markers suggest that the 6HS, 3H, and 2HS QTLs are part of resistance gene clusters and that the 6HS and 3H QTLs share homology. The 6HS QTL is identical to or closely linked to the SSLB resistance locus Rsp4 and the 1H QTL to the Rsp2 or Rsp3 locus. The 3H and 2HS QTLs are unique and offer new opportunities for pyramiding resistance genes through marker-assisted breeding for resistance to S. passerinii. 相似文献
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Sivakumar K. Chamarthi Kundan Kumar Raghavendra Gunnaiah Ajjamada C. Kushalappa Yves Dion Thin M. Choo 《European journal of plant pathology / European Foundation for Plant Pathology》2014,138(1):67-78
Fusarium head blight (FHB) and deoxynivalenol (DON) mycotoxin produced by Fusarium graminearum reduce barley yield and quality worldwide. Hundreds of quantitative trait loci (QTLs) have been identified in wheat and barley but their functions are largely unknown. Metabolic profiling was applied to better understand the mechanisms of resistance and to identify potential FHB resistance biomarker metabolites in barley. Four FHB resistant (H15-2, H148-3, H203-2 and H379-2) and one susceptible (H97-2), two-row, purple, doubled-haploid (DH) lines of barley were inoculated with either the pathogen or mock-solution. The disease severity quantified as the area under the disease progress curve (AUDPC) significantly varied between the resistant and susceptible genotypes, but not among the resistant genotypes. Neither the amount of DON nor the detoxified product, proportion of total DON, was significant among lines. The resistance related (RR, higher in abundance in resistant than in susceptible) metabolites varied in numbers and fold changes among the DH resistant lines. A total of 144 RR constitutive (RRC) and 167 RR induced (RRI) metabolites were selected, of which 39 and 37, respectively, were putatively identified. These RR metabolites mainly belonged to six chemical groups: phenylpropanoids, hydroxycinnamic acid amides, flavonoids, fatty acids, terpenoids, and alkaloids. The specific RR metabolites identified in each DH line, the possible mechanisms of resistance in each and their use as potential biomarkers are discussed. 相似文献
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Justin Choo 《Australian veterinary journal》2000,78(11):742-742
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Kim JS Song BS Lee KS Kim DH Kim SU Choo YK Chang KT Koo DB 《Reproduction in domestic animals》2012,47(5):791-798
Apoptosis is an important determinant of the normal development of pre-implantation embryos in vitro. Recently, endoplasmic reticulum (ER) stress-mediated apoptosis has been extensively investigated in a wide variety of diseases. Efficient functioning of the ER is essential for most cellular activities and survival. Tauroursodeoxycholic acid (TUDCA), an endogenous bile acid, has been reported to attenuate ER stress-mediated cell death by interrupting the classic pathways of apoptosis. Therefore, in this study, the anti-apoptotic effect of TUDCA on ER stress-induced apoptosis was examined in pre-implantation pig embryos. Also, tunicamycin was used to investigate the effects of ER stress on pig embryo development. After in vitro maturation and fertilization, presumptive pig embryos were cultured in NCSU-23 medium supplemented with TUDCA or TM for 6 days at 39 °C, 5% CO(2) in air. All data were analysed using one-way anova and Duncan's multiple range test in the statistical analysis system (SAS). In addition, we also determined the optimal TM and TUDCA concentrations. Samples were treated with TM at concentrations of 0, 1, 2 or 5 μm and with TUDCA at concentrations of 0, 100, 200 or 300 μm. When TM was used during in vitro culture, only 8.2% (8/97) of the embryos developed to the blastocyst stage when the treatment concentration was 1 μm compared with 27.4% (28/102) of the embryos in the control group (p < 0.05). In contrast, the frequency of blastocyst formation and the number of cells were higher when treated with 200 μm TUDCA compared with the control group (32.8% and 39.5 vs 22.2% and 35.6, p < 0.05). Moreover, the developmental rate to the blastocyst stage embryo in the group treated with TM and TUDCA was not significantly different from that of the control group (17.8%, 26/142 vs 24.9%, 36/145). Furthermore, the blastocyst cell number was enhanced (31.9 vs 36.9) and apoptosis reduced (TUNEL-positive nuclei number, 6.0 vs 3.2) by TUDCA treatment in pig embryos. In the real-time quantitative RT-PCR analysis, the expression of anti-apoptotic Bcl-XL gene was shown to be increased in the blastocyst stage because of TUDCA treatment, whereas expression of pro-apoptotic Bax was decreased. In addition, we also found that TUDCA decreased the rate of TM-induced apoptosis in the pre-implantation stage. Taken together, our results indicate that TUDCA improves the developmental competence of pig embryos by modulating ER stress-induced apoptosis during the pre-implantation stage. 相似文献
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Resistance of barley to Fusarium graminearum was studied using a pair each of resistant and susceptible black and yellow barley lines. The spikelets were inoculated with a trichothecene‐producing isolate, a trichothecene‐nonproducing isolate (tri5?), or a mock solution. Spikelets were collected 72 h after inoculation and metabolites were analysed using a LC‐hybrid MS system. Metabolite abundances were used to identify the constitutive (RRC) and induced resistance‐related metabolites (RRI). The pathogen virulence factor, DON, and its plant detoxification product, DON‐3‐O‐glucoside (D3G), were also identified and designated as resistance‐indicator (RI) metabolites. The RRC, RRI and RI metabolites were putatively identified. Jasmonic acid was significantly induced in barley following inoculation with a trichothecene‐producing isolate, but not with a tri5? isolate. The former isolate reduced the induction of both the number and amount of RR metabolites. The metabolites cinnamic acid, sinapoyl alcohol, coniferin, catechin and naringin were identified only in response to the inoculation with a tri5? mutant. The abundances of p‐coumaric acid, coniferaldehyde and sinapaldehyde increased more in response to the tri5? mutant than to the trichothecene‐producing isolate. The total amount of DON synthesized and its conversion to D3G varied greatly between the resistant and susceptible black barley, but not in yellow barley. Interestingly, an increase in the amount of total DON produced was associated with a decrease in the conversion of DON to D3G. The roles of RRC, RRI and RI metabolites in plant defence and their further use as potential biomarkers in screening are discussed. 相似文献