Subjects: Biology >> Botany >> Applied botany submitted time 2023-09-20 Cooperative journals: 《广西植物》
Abstract： Saxifraga L. is rich in species diversity with about 440–500 species and broad distribution. The taxonomical issues of this genus have been continuously concerned by the botanists. Saxifraga has important ornamental and medicinal values. Some of European countries have made great efforts on the exploitation and utilization of its ornamental resources. China is one of the diversity centers of Saxifraga, but it has been lagged far behind Europe, USA and even Japan in exploitation and utilization on ornamental value of this genus. The world breeding work in Saxifraga started 150 years ago. By the end of 2022, the 1 692 names of cultivars had been on-line listed by The Saxifrage Society, but only one came from China. In this paper, the germplasm resources of Saxifraga, and progress on its classification and breeding were reviewed, and also the utilization of its ornamental resources was briefly introduced, which will provide an important reference for taxonomical research, breeding and horticultural application of this genus in China. The results were as follows: (1) Saxifraga is rich in germplasms, but many scientific issues remain in the evolutionary relationships of its subordinate systems, which require a systematic and in-depth investigation by integrating morphological and molecular biology methods. (2) The cultivars of this genus are mainly raised through cross-breeding and mutant selection, and the majority of cultivars produced from the UK, Czech Republic, Germany, and the Netherlands. (3) The breeding of Saxifraga started very late in China, with only few cultivars from one breeding method.
Subjects: Biology >> Botany >> Applied botany submitted time 2020-08-02 Cooperative journals: 《广西植物》
Abstract：水花生(Alternanthera philoxeroides)因其表型可塑性、高生长速率和快速无性繁殖能适应水、陆生境。利用光学显微镜和荧光显微镜对水、陆生境的水花生不定根、茎解剖结构、组织化学特征及质外体通透性进行研究。结果表明：（1）水生境下，其不定根皮层中具较大裂生型通气组织，无次生生长，内皮层具凯氏带且栓质化，皮层和皮下层明显木质化。（2）在陆生环境下，其不定根有次生生长，胞间具通气组织，内皮层具凯氏带且栓质化，皮层和皮下层略木质化；此外，不定根还具额外形成层，产生次生维管束，薄壁组织和不定芽，多年生不定根中具直接分裂的薄壁组织，周皮具凯氏带，且栓质化和木质化。（3）水、陆生境下，其匍匐茎具髓和中空髓腔，发生次生生长，具裂-溶生型通气组织、单层内皮层、厚角组织和木质化且栓质化的角质层，陆生匍匐茎周皮栓质化且木质化。（4）水花生质外体屏障结构组成复杂，黄连素无法穿透质外体屏障结构。水花生的上述解剖学特征，是水花生适应水、陆生境的有力证据。
Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究青贮组合型全混合日粮对育肥肉牛生长性能及血液指标的影响。选取体况良好、体重[(440.5±3.5) kg]相近的西门塔尔公牛30头，随机分为2组，每组15头牛。对照组（C组）饲喂单一青贮型全混合日粮，试验组（T组）饲喂青贮组合型全混合日粮。试验期180 d。结果表明：1)第1~60天、第61~120天和第121~180天，T组的平均日采食量均显著低于C组（P≤0.05），T组的平均日增重均高于C组（P＞0.05）；第61~120天和第121~180天，T组的料重比均显著低于C组（P0.05)。4）第60天、第120天，C组的血浆尿素氮(UN)含量显著低于T组（P<0.05）；第60天，C组的血浆总胆固醇(T-CHO)含量显著低于T组（P<0.05）；第120天、第180天，C组的血浆谷草转氨酶(AST)活性显著高于T组（P≤0.05）；第180天，C组的血浆谷丙转氨酶（ALT）活性显著高于T组（P<0.05）。综上，青贮组合型全混合日粮对育肥肉牛机体抗氧化功能和健康状况无不良影响，而且可在一定程度上改善机体代谢，并可提高育肥肉牛的生长性能。
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究饲用甜高粱裹包青贮料对肉羊生产性能及血清指标的影响，以评价饲用甜高粱裹包青贮料对肉羊的饲喂效果。试验选取3～4月龄小尾寒羊[（25.70±1.50） kg]和杜泊羊[（33.40±1.68） kg]母羊各14只作为供试动物，根据饲粮中粗饲料不同将其分为杜泊羊甜高粱青贮组(DG组，n=7)、杜泊羊玉米青贮组(DY组，n=7)、小尾寒羊甜高粱青贮组(HG组，n=7)和小尾寒羊玉米青贮组(HY组，n=7)。饲养试验为期3个月，并于试验第30天、第60天和第90天早晨称重及采集血液。结果表明：1）玉米青贮组（DY组+HY组，n=14）的平均日采食量（ADFI）和平均日增重（ADG）极显著高于甜高粱青贮组（DG组+HG组，n=14）（P<0.01）。2）试验期内杜泊羊组（DG组+DY组，n=14）的血清总抗氧化能力(T-AOC)显著高于小尾寒羊组（HG组+HY组，n=14）（P<0.05）；在试验第60天，杜泊羊组血清丙二醛（MDA）含量显著低于小尾寒羊组（P<0.05）；在试验第90天，甜高粱青贮组的血清超氧化物歧化酶（SOD）活性显著高于玉米青贮组（P<0.05）；在试验第90天，HY组的血清MDA含量显著高于DY组和HG组（P<0.05）；甜高粱青贮组的血清SOD活性在试验第60天你和第90天显著高于试验第30天（P<0.05）。3）血清尿素氮(UN)含量以及谷丙转氨酶(GPT)、碱性磷酸酶(AKP)活性分别在试验第60天、第90天、第60天存在显著的品种效应（P<0.05）；血清β-羟丁酸（BHBA）含量及谷草转氨酶（GOT）、AKP活性分别在试验第90天、第30天与第90天、第60天存在显著的处理效应（P<0.05）；HY组的血清GOT和AKP活性在试验第90天显著高于试验第30天（P<0.05）。综上，饲喂含玉米裹包青贮料饲粮的肉羊的生产性能优于饲喂含饲用甜高粱裹包青贮料饲粮的肉羊，但青贮料长期育肥肉羊存在安全风险，而饲用甜高粱裹包青贮料较玉米裹包青贮料有利于提高肉羊肝脏健康、降低“高血脂”及机体酮症酸中毒等疾病的几率，进而降低安全风险。
Subjects: Biology >> Zoology submitted time 2017-10-11 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在适当降低饲粮氮水平条件下，通过饲粮添加N-氨甲酰谷氨酸（NCG）及小肠灌注葡萄糖，研究其对绒山羊小肠感应因子mRNA相对表达量、血液理化指标及激素含量的影响。选用27只体况良好、装有永久性瘤胃和十二指肠瘘管的内蒙古白绒山羊羯羊，按年龄和体重相近原则随机分成9组，每组3只。饲粮分为3个处理：低氮[粗蛋白质(CP)10.5%]、低氮+NCG（0.20 g/d）和高氮（CP 13.5%）；每个处理的山羊分别进行3个水平的十二指肠葡萄糖灌注：0、20和40 g/d。饲养试验（15 d预试期、15 d正试期）结束后，屠宰取空肠和十二指肠组织，通过实时定量PCR法测定营养感应因子mRNA相对表达量，测定血液理化指标、血清和空肠相关激素含量。结果表明：1）在基础饲粮条件（无葡萄糖灌注）下，随着饲粮氮水平的下降，空肠和十二指肠钠-葡萄糖共转运载体1（SGLT1）的mRNA相对表达量，血浆尿素氮、葡萄糖含量，血清瓜氨酸、胰岛素含量，血清和空肠胰高血糖素样肽1（GLP-1）、胰高血糖素样肽2（GLP-2）和促胰岛素肽（GIP）含量减少，而空肠和十二指肠溶质载体家族7成员9（SLC7A9）、溶质载体家族7成员1（SLC7A1）的mRNA相对表达量增加。2）增加适宜过瘤胃葡萄糖后，随着饲粮氮水平的下降，SGLT1、味觉受体1型1、味觉受体1型2、味觉受体1型3 mRNA相对表达量呈增加趋势。3）低氮饲粮条件下灌注20 g/d葡萄糖,额外饲喂NCG能够缓解饲粮氮水平降低引起的空肠和十二指肠SGLT1 mRNA相对表达量，血浆尿素氮、葡萄糖含量，血清瓜氨酸含量，血清和空肠GLP-1、GLP-2和GIP含量的下降。结果提示，适当降低饲粮氮水平，补饲NCG和增加过瘤胃葡萄糖（十二指肠灌注20 g/d）对绒山羊机体代谢及肠道营养物质感应均有促进作用。
Subjects: Biology >> Bioengineering submitted time 2017-07-24 Cooperative journals: 《中国生物工程杂志》
Abstract： Objective: The XylR-Pu is a classic toluene catabolic pathway, which is from TOL plasmid of Pseudomonas putida. In the presence of toluene, the XylR regulatory protein can activate Pu promoter and thus induce expression of corresponding metabolic genes. To detect 2,4,6-trinitrotoluene (TNT),the significant environmental pollutant, the pathway was optimized and put into Escherichia coli to construct whole-cell biosensor, which was based on the idea of synthetic biology. E.coli was chosen as chassis cell due to its genetic background was clear and it was simple to operate. Methods: pETDuet-1 was used as backbone to construct gene circuit of XylR-Pu, XylR was inserted in first multi cloning site . The second T7 promoter was substituted by Pu promoter and reporter gene of green fluorescent protein was under the control of Pu promoter . The fluorescent values can indicate the strength of the activation of XylR protein to Pu promoter. Then four series terminator was inserted between XylR and Pu to minimize background expression. Finally, the receptor domain of XylR protein was randomly mutated using sequential error prone PCR to construct a mutant library and to identify XylR mutants, which can be more sensitive and specific to TNT. Results: The four series terminator can effectively prevent read-through and decrease background fluorescent. After selection, one mutant protein named eX0-4 displayed better induction intensity, sensitivity and specificity to TNT. Conclusions: As Nitrobenzene was not XylR natural inducer, so XylR showed no obvious response to TNT. But the method is feasible to modify the A domain of XylR protein to obtain non-natural but better protein components. The mutant of eX0-4 enriched the reservoir of TNT-sensing elements, and provided a more applicable toolkit to be applied in genetic routes and live systems of biosensors in future. It can be a common method to identify biological elements to use error prone PCR to construct mutant library.
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