条带式改良陡坡草地生产性能的研究

本试验对条带式补播改良陡坡草地的生产性能进行了研究。试验根据坡度分为小于25°、25～35°和大于35°的坡地三个处理组。其结果表明,条带式改良草地可以提高产草量,较天然草地三个坡度级分别提高200.39、253.12和203.27%(P<0.01),又可以改善草群品种,豆科牧草分别占总产草量的48.97、72.33和84.14%,且有毒有害植物明显减少。植被盖度由原来的42.5%增加到83.5%,将蒿属植物为建群种的群落变为沙打旺—野艾蒿—万年蓬组成的群落。     

Astragalus polysaccharides protects against free fatty acid-induced human vascular endothelial cell dysfunction via AMPK-eNOS pathway

AIM: To study the protective effect of Astragalus polysaccharides (APS) on free fatty acid-induced injury in human umbilical vein endothelial cells (HUVECs). METHODS: Cultured HUVECs were divided into control group, APS group [APS (200 mg/L) treated for 24 h], free fatty acid group [free fatty acid (0.25 mmol/L) treated for 24 h], free fatty acid plus APS group [free fatty acid (0.25 mmol/L) and APS (200 mg/L) treated for 24 h], and compound C group [free fatty acid (0.25 mmol/L) and APS (200 mg/L) and AMPK inhibitor compound C (10 μmol/L) treated for 24 h]. The cell viability was detected by MTT assay. Nitric oxide (NO) content in the medium was determined by nitrate reductase assay. The protein levels of total adenosine monophosphate-activated protein kinase (AMPK), phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), endothelial nitric oxide synthase (eNOS) and phosphorylated endothelial nitric oxide synthase (p-eNOS) were measured by Western blot. RESULTS: No significant difference of all indexes between APS group and control group was observed. The cell viability in free fatty acid group decreased significantly compared with control group. The cell viability in free fatty acid plus APS group was significantly improved as compared with free fatty acid group. The cell viability in compound C group was almost the same as that in free fatty acid group. The No content and protein levels of p-AMPK and p-eNOS in free fatty acid group decreased obviously as compared with control group, while the NO content and protein levels of p-AMPK and p-eNOS in free fatty acid plus APS group increased obviously compared with free fatty acid group. No significant difference of the p-AMPK and p-eNOS protein levels between free fatty acid plus APS group and free fatty acid group was observed. No significant difference of the AMPK and eNOS protein levels in all groups was found. CONCLUSION: APS attenuates the free fatty acid-induced injury, and its mechanism is related to the AMPK-eNOS signal pathway.     

Morphological variation in Astragalus hamosus L. and Coronilla scorpioides L. populations of Tunisia

Morphological variation between Astragalus hamosus and Coronillascorpioides populations was studied using local germoplasm collected in northern and central Tunisia. Twenty-one morphological traits were recorded and data were analysed using complementary statistical analysis. Considerable variation based on morphological and agronomical traits was found between populations and for both species. Pod and peduncle lengths as well as flowers number were the most discriminant variables between populations. Differences were also found for variables like seed number per pod, seed yield and dry matter production. Significant correlations were found between plant traits and the environmental parameters of the origin sites. This study revealed enough variation among populations to initiate a selection programme for pasture improvement in arid and semi-arid areas of Tunisia, where the two species are well adapted. This revised version was published online in July 2006 with corrections to the Cover Date.     

大豆基因组SSR和EST-SSR在黄芪中的通用性分析

分子标记的种间通用性可降低其开发成本,提高利用效率,促进遗传研究较薄弱物种的分子遗传学研究。为开发黄芪SSR分子标记,本研究利用大豆的66对基因组SSR(G-SSR)和43对EST-SSR引物在黄芪基因组中进行通用性分析,并选出其中条带清晰易辨的23对引物对6种不同来源的黄芪进行遗传分析。结果表明:大豆G-SSR、EST-SSR引物在黄芪中的通用性比例分别为31.82%、76.74%,多态性引物分别占18.18%、53.49%,大豆EST-SSR在黄芪的通用性高于基因组SSR,且通用的大豆SSR标记可以用于不同来源黄芪的遗传多样性分析。本研究发掘的多态性SSR引物可以有效用于黄芪的分子遗传多样性研究。     

共培养对土壤重金属污染植物修复的调控作用

A co-culture of two plant materials, Astragalus sinicus L., a leguminous plant with concomitant nodules, and Elsholtzia splendens Naki-a Cu accumulator, along with treatments of a chelating agent (EDTA), root excretions (citric acid), and a control with E. splendens only were used to compare the mobility of heavy metals in chelating agents with a co-culture and to determine the potential for co-culture phytoremediation in heavy metal contaminated soils. The root uptake for Cu, Zn, and Pb in all treatments was significantly greater (P < 0.05) than that of the control treatment. However with translocation in the shoots, only Cu, Zn, and Pb in plants grown with the EDTA treatment and Zn in plants co-cropped with the A. sinicus treatment increased significantly (P < 0.05). In addition, when a co-culture in soils with heavy and moderate contamination was compared, for roots in moderately contaminated soils only Zn concentration was significantly less (P < 0.05) than that of heavily contaminated soils, however, Cu, Zn, and Pb concentrations of shoots were all significantly lower (P < 0.05). Overall, this "co-culture engineering" could be as effective as or even more effective than chelating agents, thereby preventing plant metal toxicity and metal leaching in soils as was usually observed in chelate-enhanced phytoremediation.     

黄花变异黄芪化学成分预试及生物碱成分初步分析

对黄花变异黄芪的化学成分进行了系统预试,对其总生物碱进行了提取和分段萃取,并用TLC法对分段萃取物进行了检查。结果表明,黄花变异黄芪含有糖、有机酸、酚类、鞣质、氨基酸、蛋白质、甙类或多糖、皂甙、生物碱、黄酮、蒽醌、香豆素、萜类、内脂、甾体等成分,不含挥发油、油脂、氰甙和脂肪族硝基化合物;黄花变异黄芪的生物碱主要以强极性生物碱为主,约占总生物碱的97.25%;对三段萃取物的TLC检查发现,黄花变异黄芪中含有苦马豆素,且主要存在于乙酸乙酯萃取部分和正丁醇萃取部分。     

紫云英根瘤菌分子遗传学研究进展

总结了紫云英根瘤菌分子遗传学研究进展。这类根瘤菌的寄主范围较窄，早先根据互接种族概念将其定名为Rhizobium astragali。后来定名为Rhizobium huakuii。最近并入Mesorhizobium属，对大量菌株进行的16S和23SrDNAPCR-RFLP分析和代表菌株的部分16SrDNA碱基测序，揭示了7个不同基因型，表明这类菌具有遗传多样性。可以认为存在不同的种，它们都有质粒，数量1-5个，因菌株而异，可分为不同质粒型。共生基因常定位在最大的一个质粒上，即共生质粒，它们的结瘤基因具有独特结构。采用包括nodA,nodB。noC,nodD的苜蓿根瘤菌突变株进行基因互补，从紫云英根瘤蓖基因文库中获得了相应的转移接合子，这类结瘤基因的这种结构在7个基因型的菌株中都是一致的，说明结瘤基因的保守性。     

紫云英根瘤菌天然抗药性和质粒研究

从同一稻田的紫云英根瘤上共分离到１５４株紫云英根瘤菌。将来自该田块１０株紫云英的１００株根瘤菌列为分析组Ａ；来自同一植株不同根瘤的４０株根瘤菌列为分析组Ｂ；来自植株两个根瘤的１４株根瘤菌列为分析组Ｃ。对所有菌株１０种抗生素的抗药性测定表明，分析组３９个不同抗药类群；分析组Ｂ分为２２个抗药类群。同一根瘤的分离株其抗药性也存在差异。质粒检测显示所有菌株都含有质粒，质粒数为１－５条；质粒分子量主要在８     

翻压等量紫云英条件下不同化肥用量对土壤养分有效性及水稻产量的影响

在翻压等量紫云英条件下,研究了不同化肥用量对土壤养分有效性及水稻产量的影响.结果表明,早稻田翻压紫云英22500 kg/hm2后配施化肥,与施用100％化肥(MF100)相比,施用60％～80％化肥,土壤中碱解N、速效钾含量均有增加,增幅为10％～59％;施用40％化肥,土壤中有效磷含量显著增加25％ ～ 80％.翻压...     

安疫肽、肽好、高免多糖对雏鸡免疫功能的影响试验研究

对免疫新城疫、法氏囊和处于免疫抑制状态的雏鸡使用安疫肽(Compound amino acid solution,VESPRO solution)(饮水、注射)、肽好(Immunoglobulin powder,IG powder)(饮水)、高免多糖(Astragalus Polysaccharide powder,APS powder)(饮水),测定新城疫免疫、法氏囊免疫后的各免疫学指标、抗体水平、白细胞介素产生及免疫抑制鸡群白细胞介素产生、抗体水平。结果表明,肽好组、安疫肽饮水组对脾脏、法氏囊、胸腺的发育有较显著的影响,其中安疫肽饮水使用效果最佳,高免多糖有提高法氏囊指数的作用。安疫肽、肽好、高免多糖均对提高抗体水平较好,安疫肽饮水、注射及高免多糖,均能在提高抗体水平的基础上提高整齐度。