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21.
Either before or after curing their cut surfaces for 5 days, 7 cm- and 15-cm-long decapitated Hylocereus trigonus cuttings were treated by soaking their apical or basal ends in benzyladenine (BA) solution. They were then planted and grown in a greenhouse.For the 7 cm-long cuttings, BA (25–100 mg l?1) applied to the apical ends for 24 h increased the ratio of cuttings with sprouted buds to 64–100%, the number of sprouted buds to 1.9–3.1 and of shoots to 1.6–2.8, and the shoot length to 35–60 mm, compared to the water control which showed 13%, 1.0, 1.0 and 12.5 mm, respectively. Soaking the basal part had only a small effect.Naphthylacetic acid (NAA) applied to the basal ends of cuttings immediately after cutting increased the number of sprouted buds and shoots by inducing early rooting. The number and length of BA-induced axillary shoots in the longer cuttings was greater than those in the shorter ones.In the 15-cm-long cuttings, increasing the soaking time from 5 min to 24 h resulted in a greater promotive effect of BA on shoot formation. BA applied before curing showed the same effect as that given after curing but caused necrosis of the tissue just under the cut surface. Enlarging the area soaked in BA solution from 5 cm to 10 cm decreased the number of sprouting buds and shoots.  相似文献   
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The molecular mechanisms controlling human hair growth and scalp hair loss are poorly understood. By screening about 350,000 individuals in two populations from the Volga-Ural region of Russia, we identified a gene mutation in families who show an inherited form of hair loss and a hair growth defect. Affected individuals were homozygous for a deletion in the LIPH gene on chromosome 3q27, caused by short interspersed nuclear element-retrotransposon-mediated recombination. The LIPH gene is expressed in hair follicles and encodes a phospholipase called lipase H (alternatively known as membrane-associated phosphatidic acid-selective phospholipase A1alpha), an enzyme that regulates the production of bioactive lipids. These results suggest that lipase H participates in hair growth and development.  相似文献   
24.
Seed dormancy contributes resistance to pre-harvest sprouting.Effects on respective quantitative trait loci (QTLs) for dormancy should be assessed by using fresh seeds before germinability altered through storage.We investigated QTLs related to seed dormancy using backcross inbred lines derived from a cross between Nipponbare and Kasalath.Four putative QTLs for seed dormancy were detected immediately after harvest using composite interval mapping.These putative QTLs were mapped near C1488 on chromosome 3 (qSD-3.1),R2171 on chromosome 6 (qSD-6.1),R1245 on chromosome 7 (qSD-7.1) and C488 on chromosome 10 (qSD-10.1).Kasalath alleles promoted dormancy for qSD-3.1,qSD-6.1 and qSD-7.1,and the respective proportions of phenotypic variation explained by each QTL were 12.9%,9.3% and 8.1%.We evaluated the seed dormancy harvested at different ripening stages during seed development using chromosome segment substitution lines (CSSLs) to confirm gene effects.The germination rates of CSSL27 and CSSL28 substituted with the region including qSD-6.1 were significantly lower than those of Nipponbare and other CSSLs at the late ripening stage.Therefore,qSD-6.1 is considered the most effective novel QTL for pre-harvest sprouting resistance among the QTLs detected in this study.  相似文献   
25.
N-Methyl-N-nitrosourea (MNU)-induced renal tumors in rats and Wilms tumors in humans were compared. Renal mesenchymal tumors (RMTs) and nephroblastomas (blastemal and epithelial components) in female Lewis rats treated with a single intraperitoneal injection of 50 mg/kg MNU at birth and Wilms tumors (blastemal, epithelial and mesenchymal components) in humans were analyzed for the expression of pancytokeratin (CK), vimentin, p63, α-smooth muscle actin (SMA), desmin, S-100, CD57, CD117/c-kit, Wilms tumor 1 protein (WT1) and β-catenin. The mesenchymal components of rat RMTs and human Wilms tumors expressed vimentin, SMA and β-catenin. The blastemal components of rat nephroblastomas and human Wilms tumors expressed vimentin, CD117/c-kit and β-catenin. The epithelial components of rat nephroblastomas and human Wilms tumors expressed vimentin and β-catenin. WT1 was expressed in different cellular components of rat tumors as compared with human Wilms tumors; the expression was seen in mesenchymal tumors and blastemal components of nephroblastomas in rats and epithelial components in human Wilms tumors. CK, p63 and CD57 were not expressed in rat RMTs or nephroblastomas, while CK and WT1 were expressed in epithelial components and CD57 was expressed in blastemal and epithelial components of human Wilms tumors. Rat and human tumors were universally negative for the expression of desmin and S-100. The immunohistochemical characteristics of rat renal tumors and human Wilms tumors may provide valuable information on the differences in renal oncogenesis and biology between the two species.  相似文献   
26.
We aimed to define whether embryo collection carried out after pseudopregnancy was of similar outcome and quality as after artificial abortion. To induce pseudopregnancy, 30 gilts or sows were given 20 mg intramuscular estradiol dipropionate (EDP) 10–11 days after the onset of estrus. Ten additional pigs were inseminated artificially at natural estrus as a control group. Prostaglandin F (PGF) was administered twice with a 24 hr interval beginning 15, 20, or 25 days after EDP‐treatment (n = 10 per group) or between 23 and 39 days after artificial insemination in control pigs. Following this, all pigs were given 1,000 IU equine chorionic gonadotropin and 500 IU human chorionic gonadotropin (hCG) and then inseminated. Embryos were recovered 6 or 7 days after hCG treatment and outcome was recorded. There was no significant difference in the number of normal embryos collected from the pigs with PGF initiated at different time points or from the control group. Embryonic developmental stages 7 days after hCG treatment also did not differ among groups. These results indicate that the use of EDP to induce pseudopregnancy, followed by PGF administration to synchronize estrus for subsequent embryo harvest, is a suitable alternative to the artificial abortion method.  相似文献   
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The fishery biology of mud crabs Scylla spp. was examined using baited traps and gill nets from September 2001 to August 2005 at Iriomote Island, Japan. To elucidate the growth of the crabs, artificially produced S. serrata juveniles were released and recaptured at the study site. The sizes at which 50% of females and males of S. serrata reached sexual maturity (SM50) were estimated as an external carapace width (ECW) based on the morphology of the abdomen and the chela respectively. Two species, S. serrata and S. olivacea, were identified in the area with S. serrata being the dominant species (>95% of the catch). Changes in the mean ECW and the results of the release and recapture experiments suggested that the recruitment of young crabs to the fishery occurred from December/January to April/May. The SM50 of females and males occurred at 132.4 and 150.7 mm ECW respectively. The body size composition of S. serrata revealed that immature crabs comprised approximately 40 and 65% of the catch for females and males respectively. To maintain a sustainable fishery for S. serrata, a minimum landing size based on the SM50 estimates should be implemented as a fishing regulation.  相似文献   
29.
Powdery mildew, caused by Podosphaera xanthii (syn. Sphaerotheca fuliginea ex Fr. Poll.), is one of the most economically important foliar diseases in cucumber (Cucumis sativus L.). Cucumber parental line ‘Kyuri Chukanbohon Nou 5 Go’, developed from weedy cucumber line CS-PMR1, is highly resistant to powdery mildew and is promising breeding material. We performed quantitative trait locus (QTL) analysis using double-digest restriction-site-associated DNA sequencing (ddRAD-Seq) in a population from a cross between ‘Kyuri Chukanbohon Nou 5 Go’ and the Japanese native cultivar ‘Kaga-aonaga-fushinari’, which is susceptible to powdery mildew. The resistance of the population and its parents was evaluated using leaf disc assays and image analysis. We detected one major QTL on Chr. 5 that was effective at both 20°C and 25°C and one minor QTL on Chr. 1 effective at 20°C. We detected two additional QTLs in subpopulation: one on Chr. 3 effective at 20°C and one on Chr. 5 effective at both 20°C and 25°C in a position different from the major QTL. The resistance alleles at all four QTLs were contributed by ‘Kyuri Chukanbohon Nou 5 Go’. The results of this study can be used to develop practical DNA markers tightly linked to genes for powdery mildew resistance.  相似文献   
30.
Densely branched lateral roots (DBLRs) in Sesbania cannabina are formed in response to patchily distributed phosphorus (P) in volcanic soils. Little attention has been paid to morphological and physiological responses of DBLRs. Here, we investigated the relation between plant growth and DBLR development, enzymatic activities involved in P acquisition, and the influence of arbuscular mycorrhizal fungi (AMF), which contribute to P uptake, to clarify the function of DBLRs. We investigated DBLR development induced by localized application of P fertilizer and we compared the activities of phosphoenolpyruvate carboxylase (PEPCase) and acid phosphatase (APase) between DBLRs and non‐DBLRs. Additionally, plants were grown with or without AMF to investigate the effect of AMF colonization on the numbers of DBLRs and plant P uptake, and we compared AMF colonization between DBLRs and non‐DBLR roots. Secondary to quaternary lateral DBLRs were produced after the primary lateral roots passed near P fertilizer. Pi content per DBLR increased as DBLRs developed, promoting higher shoot growth. Under P deficiency, PEPCase and APase activities increased in non‐DBLR, but were significantly lower in DBLRs in the same plants. AMF inoculation changed the root system architecture by significantly decreasing the number of DBLRs, and AMF colonization was lower in DBLRs than in non‐DBLRs. Our results indicate that DBLR formation is a P‐coacquisition strategy of S. cannabina grown in P‐deficient andosolic soil. Roots that form DBLR are clearly different from non‐DBLR roots in morphological and biochemical response and AMF symbiosis.  相似文献   
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