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91.
Genome size variation in three Saccharum species   总被引:1,自引:0,他引:1  
Saccharum species are autopolyploids with ploidy level ranging from 5× to 16x, and are considered the most complex genomes among crop plants. In present study, the genome sizes of 28 Saccharum spontaneum accessions, 15 Saccharum officinarum accessions, 28 Saccharum robustum accessions, and 12 Saccharum hybrids spp. were analyzed using flow cytometry. The estimated genome sizes of S. officinarum accessions ranged from 7.50 to 8.55?Gb with an average size of 7.88?Gb. In S. robustum, the estimated genome sizes ranged from 7.65 to 11.78, reflecting the variation of ploidy level. In S. spontaneum, the estimated genome sizes varied widely, with a range from 3.36 to 12.64?Gb, also due to variation of ploidy level. The average monoploid genome size of S. officinarum was 985?Mb, and that of S. spontaneum was 843?Mb. The results also showed that genome sizes were correlated with chromosome numbers, and based which, that the unknown chromosome numbers of some accessions could be predicted. The estimated genome sizes of Saccharum germplasm also helped identify some mislabeled accessions and yielded information critical for sugarcane breeding and genome sequencing programs.  相似文献   
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This study aimed to establish a culture system that improves the in vitro development of caprine preantral follicles. In a first experiment, follicles were encapsulated as a single unit per bead and cultured singly or in groups or with five follicles in the same alginate (ALG) bead for 18 days. In a subsequent experiment, the “five follicles per bead” design was chosen to culture in ALG, fibrin–alginate (FA) or hyaluronate (HA) for 18 days. In a third experiment, we chose the five follicles per bead in FA to culture for 30 days. The culture set‐up of five follicles per ALG bead increased antrum formation and follicle diameter compared to the other culture designs (p < .05). Moreover, under this condition, 44.44% of the oocytes from in vitro cultured preantral follicles reached meiotic resumption. A significant increase of follicle diameter occurred in attachment system and FA (p < .05), but the ALG condition reached the highest among all groups on day 18 (p < .05). Follicles encapsulated in matrix produced more estradiol and progesterone than attachment system (p < .05). The expression of MMP‐9 mRNA was higher in FA than in other groups (p < .05) and similar to antral follicles from in vivo control (p > .05). Only FA group resulted in oocytes matured. After 30 days, oocytes from preantral follicles in vitro grown in FA developed to eight‐cell parthenotes. In conclusion, a culture system using FA supported the development of caprine preantral follicles cultured in group and included in the same bead of hydrogel, improving the oocyte maturation and producing parthenotes.  相似文献   
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Ultrasound is one of the most promising forms of non‐invasive contraception and has been studied in several animal models. The objective of the current investigation was to determine the most practical and effective application protocol for dog sterilization. A total of 100 dogs were divided into five equal groups. Group A received 5‐min applications three times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz; Group B received 5‐min applications three times performed at 48‐hr intervals over the dorso‐cranial area of the testis at frequency of 3 MHz; Group C received three sequential 5‐min applications (at 5‐min intervals between applications) covering the entire testicular area at frequency of 1 MHz; Group D received 15‐min applications two times performed at 48‐hr intervals and covering the entire testicular area at frequency of 1 MHz. The experimental groups' ultrasound had an intensity of 1.5W/cm2. The Control Group had the same procedure as Group A, but with the transducer switched‐off. Dogs were surgically castrated 40 days following the treatment for histological examination. Azoospermia, testicular volume reduction and apparently irreversible testicular damage were achieved by Group A. No effects were noticed in the other groups. Testosterone levels remained within physiological range with all application protocols. A regimen of three applications of ultrasound at 1 MHz, and 1.5 W/cm2, lasting 5 min with an interval of 48 h was effective as permanent sterilization in the dog without hormonal impact.  相似文献   
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This study evaluated the biomass production potential of Saccharum barberi (Jeswiet) and Saccharum sinense (Roxb. Amend. Jeswiet) accessions under short‐term flooded conditions. Plots were arranged in a completely randomized design with 20 S. sinense and 29 S. barberi accessions, two flood durations with non‐flooded controls and three replications of each treatment. There were no significant flood effects. However, in two individual accessions, ‘China’ and ‘Lu Cane’, sucrose production increased with additional flooding. The plant cane produced larger plants with a greater percentage of fibre and sucrose. Higher Brix values were obtained with the ratoon crop. Brix and fibre were negatively correlated with stem diameter. Stem length in S. barberi was the only physical characteristic that was correlated with sugar factors Brix and optical rotation. S. barberi accessions had high loadings for variables associated with sugar production and stem length, and fibre had moderate loadings for factor 1. Factor 1 explained 35 % of variance in the data. The second principal factor revealed high loadings for variables associated with plant size. Factor 2 explained 30 % of the proportional and together with Factor 1 explained 65 % of the cumulative variance in the data. Several accessions with low sucrose, high plot weight and low fibre were identified. These accessions make attractive selections in breeding for biomass production.  相似文献   
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Cashew apple juice has the potential to be a natural source of vitamin C and sugar in processed foods. The juice of the cashew apple is obtained by pressing the fleshy peduncle or receptacle, which forms a rounded apple that sits above the true fruit, the cashew nut. Cashew nut allergy is the second most commonly reported tree nut allergy in the United States. To determine if cashew apple juice contains cashew nut allergens, immunoblotting was performed using a cashew apple juice 6X concentrate that was extracted and further concentrated through dialysis, lyophilization, and resuspension. Serum IgE of individuals allergic to cashew nut bound proteins in the cashew apple juice concentrate extract. For some serum samples, IgE reactivity could be inhibited by preincubation of the serum with cashew nut extract, suggesting the presence of cashew nut-related allergens. Using monoclonal antibodies specific for cashew nut allergens, the concentrate was found to contain Ana o 1 (vicilin) and Ana o 2 (legumin). Neither IgE from cashew nut allergic sera nor the monoclonal antibodies bound any peptides in 5 kDa filtered cashew apple juice concentrate. The cashew apple juice concentrate used in these studies contains proteins with IgE-reactive epitopes, including cashew nut legumin and vicilin. No IgE-binding peptides remained after 5 kDa filtration of the concentrate.  相似文献   
100.
Puccinia kuehnii and P. melanocephala cause orange and brown rust of sugarcane, respectively. Puccinia kuehnii has been confirmed in Asia, Australia and recently, the Caribbean basin, whereas P. melanocephala is distributed among the majority of sugarcane growing regions. Differentiating these two economically significant pathogens visually is problematic and limited to material exhibiting mature disease symptoms or spores. Partial ITS1, ITS2 and complete 5·8S sequences were generated from P. kuehnii and P. melanocephala isolates from around the world. PCR primers and dual labelled hydrolysis probes were designed for each pathogen for use in real‐time PCR and optimized using locked nucleic acids (LNA). The primers amplified DNA from their target pathogens and not from other species of Puccinia or fungal species isolated from sugarcane leaves. Optimized real‐time PCR conditions allowed the detection of 0·19 pg of P. kuehnii or P. melanocephala genomic DNA and differentiated the pathogens on sugarcane leaves prior to observing typical symptoms in the field. Primer‐introduced restriction analysis‐PCR (PIRA‐PCR) was used to detect a single nucleotide polymorphism (Pk ITS1 183A>G) in ITS1 of P. kuehnii. Allele 183A was observed in all samples, whereas 183G was detected in 52% of samples from Asia and Australia yet absent from all Caribbean basin samples. Long distance spore dispersal, dispersal through an intermediate location or improper movement of contaminated material could explain the introduction of P. kuehnii to the Western hemisphere. However, the current proliferation of the pathogen in the Americas is limited to isolates which contain only the 183A allele.  相似文献   
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