外源性孕酮对牛卵母细胞体外核成熟的影响

了研究外源性孕酮对牛卵母细胞体外核成熟的作用,通过向成熟培养液中添加10 μg/mL FSH +10 μg/mL LH（对照组）和0 ng/mL、10 ng/mL、100 ng/mL、1000 ng/mL的外源性孕酮,对牛卵丘卵母细胞复合体进行体外成熟培养,在培养8 h后用醋酸地衣红染色观察各自的生发泡破裂率,然后在成熟22 h统计第一极体率,体外受精后7~8天统计囊胚率。结果表明,对照组卵母细胞的生发泡破裂率(75.0%)和极体率(79.6%)均明显高于添加不同浓度孕酮的各处理组(P<0.05),而囊胚率各组之间均无显著差异(P>0.05)。因此,外源性孕酮不能促进牛卵母细胞的核成熟,单独添加外源性孕酮不能起到与内源性孕酮相同的作用。     

接骨木硬枝扦插繁殖技术研究

以2年生接骨木无性系硬枝为试验材料,对其扦插最适生根剂种类及浓度进行探讨。结果表明：生根剂ABT1、NAA、IBA对接骨木硬枝扦插生根率平均值分别为62.5%、71.6%、73.4%,其中200 μg/mL的NAA处理2 h,平均扦插生根率达80.6%;枝条下部(80.5%)、中部(78.3%)的插穗生根效果明显优于上部(51.4%);不论哪种生根剂,上部插穗的平均根长及根数均小于中部和下部;不同部位插穗平均叶片数变化不大,而抽枝长度变化较大,其中下部插穗在200 μg/mL的NAA处理2 h,平均抽枝长度达15.75 cm。接骨木硬枝扦插以愈伤组织生根为主,属于愈伤组织生根类型。结合生根率及各生长性状综合评价接骨木硬枝扦插繁殖效率,最适生根剂种类及浓度为100 μg/mL的NAA处理1 h。研究结论对提高接骨木硬枝扦插繁殖系数具有重要意义。     

外源植物激素对燕麦种子萌发和幼苗生长的影响

以燕麦品种坝莜3号为研究对象,研究不同浓度的GA_3和6-BA对燕麦种子萌发和幼苗生长的影响。结果表明,300 μg·g~(-1)、400 μg·g~(-1) GA_3处理的发芽势和发芽指数显著低于其他处理。GA_3浓度为400 μg·g~(-1)时,燕麦种子萌发率显著低于对照;6-BA浓度为2μg·g~(-1)时,燕麦种子萌发率最高。GA_3浓度为0～400 μg·g~(-1)时,燕麦根长、根长/苗长随着浓度的增加而减小;对照、100 μg·g~(-1)、400 μg·g~(-1) GA_3处理的根重显著高于500 μg·g~(-1) GA_3处理的;300 μg·g~(-1)、500 μg·g~(-1) GA_3处理的根重/苗重显著低于其他处理。6-BA在低浓度时促进(0.02 μg·g~(-1)),高浓度时(2 μg·g~(-1)、20 μg·g~(-1))抑制燕麦根和地上部分的伸长。6-BA处理的根重/苗重在高浓度时(2 μg·g~(-1)、20 μg·g~(-1))减小。燕麦种子萌发和幼苗生长的最适GA_3、6-BA浓度分别为100 μg·g~(-1)、2μg·g~(-1)。     

化学脱叶催熟剂对早熟陆地棉新陆早51号应用效果的研究

采用2种脱叶剂,设置不同的用量处理,研究化学脱叶催熟剂对早熟陆地棉新陆早51号脱叶率、吐絮率、产量和纤维品质的影响。喷施2种脱叶剂18d后,脱吐隆3个剂量处理的脱叶率差异极显著,处理A〔脱吐隆+乙烯利(150g+1800mL/hm²)」要显著低于处理B[脱吐隆+乙烯利(225g+1800mL/hm²」和C[脱吐隆+乙烯利(300g+1800mL/hm²」;80%瑞脱隆3个剂量处理的脱叶率差异不显著,均在95%左右。不同处理的2种药剂对单铃重、产量和纤维品质影响不显著。从试验结果和成本效益考虑,新陆早51号施用脱吐隆2258+乙烯利1800mL/hm²或80%瑞脱隆300g+乙烯利1800mL/hm²较为经济。     

宁夏地区大籽蒿精油成分分析及其抑菌性研究

为探究宁夏大籽蒿(Artemisia sieversiana Ehrhart ex Willd.)精油成分、抑菌功能及安全性,采用水蒸气蒸馏法进行精油提取,通过气相色谱-质谱连用法(GC-MS)进行成分分析,采用滤纸片法测定其对3种菌的抑菌圈直径,测定最低抑菌浓度(MIC)、最低杀菌浓度(MBC),并通过cck-8法检测大籽蒿精油对于2种皮肤细胞的毒性作用。结果表明,宁夏大籽蒿精油的主要成分为母菊薁(29.61%),樟脑(4.80%)、桉叶油醇(4.32%)、异木香酸甲酯(4.02%);精油对铜绿假单胞菌和大肠杆菌的最低抑菌浓度为0.0781 μg/mL,最低杀菌浓度为0.3125 μg/mL;金黄色葡萄球菌MIC为0.0195 μg/mL,MBC为0.078125 μg/mL;当精油浓度小于100 μg/mL时对角质细胞(HaCaT)和皮肤成纤维细胞(NHSF)均无毒性。综上,宁夏地区大籽蒿精油具有较强的抑菌活性且安全性较高,以上结果为宁夏大籽蒿精油开发提供理论依据,以期为当地脱贫致富提供科技支撑。     

高效液相色谱法测定羧甲基壳聚糖/水杨酸处理的葡萄柚果实中水杨酸含量

以葡萄柚果实为试材,分别采用三氯乙酸/乙醚、三氯乙酸/三氯甲烷、乙酸乙酯/环己烷提取果皮水杨酸,采用高效液相色谱法测定其含量,筛选得出简单易行的提取及测定葡萄柚果皮水杨酸含量的方法.利用此方法对15 g/L羧甲基壳聚糖(CMC)、200mg/L水杨酸(SA)单独及复合处理的葡萄柚果皮内源水杨酸含量进行测定分析.结果表明,可采用三氯乙酸/乙醚从葡萄柚果皮提取的水杨酸分离效果较好,测定最佳色谱条件为:Eclipse XDB-C18柱(150 mm×4.6 mm,5 μm),流动相0.2 mol/L pH 5.5乙酸钠缓冲溶液-甲醇(40∶60),检测波长296 nm,流速0.8 mL/min,进样量5 μL.水杨酸质量浓度在3.91～500 μg/mL范围内与峰面积呈现良好的线性关系,处理样品果皮的游离态水杨酸含量范围为18～47.6 μg/g,结合态水杨酸含量范围是68.05～73.85 μg/g.在室温贮藏的28 d内,相比未处理果实(对照),经诱导处理的游离态水杨酸和结合态水杨酸含量均呈升高的趋势,羧甲基壳聚糖/水杨酸复合处理的游离态水杨酸含量显著高于单独处理含量(P＜0.05).采用三氯乙酸/乙醚提取葡萄柚果皮水杨酸具有较高的分离度,本试验所得HPLC方法简单易行,可以用于葡萄柚果皮内源水杨酸的提取分离和测定.     

茶多酚和槲皮素对炎性脂肪细胞信号通路和炎性因子的影响

旨在研究茶多酚(TP)、槲皮素(Que)及两者协同作用时的抗炎作用机理。以TNF-α 诱导的炎性3T3-L1 脂肪细胞为模型,分别添加50 μg/mL 茶多酚(TP)、50 μg/mL 槲皮素(Que)及50 μg/mL 的茶多酚和槲皮素(TP+Que)共同处理,以空白组作为对照组。研究脂肪细胞中炎性因子白介素12(IL-12)、一氧化氮合酶(iNOS)的基因表达,并采用Western blot 研究其对Sirt1 和AMPK的磷酸化水平的影响。结果表明：在TNF-α 刺激条件下,茶多酚和槲皮素对炎性因子的基因表达和炎症信号通路都有着明显的抑制作用,但槲皮素的抑制作用则不如茶多酚显著。在脂肪细胞中,活性物质可通过AMPK/Sirt1 途径,调节IL-12和iNOS的基因表达发挥抗炎作用。     

白芨外泌体的分离及对体外人永生化角质形成细胞(Hacat)的凋亡保护研究

探索鲜白芨(Bletilla striata)外泌体对体外人永生化角质形成细胞(Hacat)的生物活性,为其在护肤品上的开发提供数据。聚乙二醇(PEG)沉淀法提取白芨外泌体,透射电镜鉴定,BCA法测蛋白浓度;细胞计数试剂(Cell Counting Kit-8,CCK8)法检测Hacat细胞存活率,流式双染检测凋亡,蛋白印迹法检测凋亡相关通路蛋白。白芨外泌体呈茶杯状具双层膜,平均粒径69.63 nm,每克鲜白芨含外泌体浓度为5.24E+8 Particles,内含蛋白19.53μg;白芨外泌体(≥5μg/mL)可显著提高体外Hacat细胞存活率(P<0.05);10μg/mL白芨外泌体处理48h,可显著降低H₂O₂氧化造模引起的Hacat细胞早凋亡、晚凋亡和总凋亡的细胞比例(P<0.01),同时,模型组caspase-9和caspase-3表达显著上升,外泌体处理能显著降低其表达,而Bcl-2表达在组间无差异(P<0.05)。PEG沉淀法分离的白芨外泌体,可促进体外Hacat生长,抑制H2O2引起的细胞凋亡且与蛋白caspa...     

超高效液相色谱串联质谱非衍生化法测定土壤中草甘膦及其代谢物氨甲基膦酸含量

为了建立土壤中草甘膦(Glyphosate）及其主要代谢物氨甲基膦酸(AMPA)残留的定量分析方法,采用固相萃取结合液相色谱串联质谱技术,样品以磷酸钠和柠檬酸三钠混合溶液提取,经固相萃取柱净化,采用正向亲水性液相色谱柱(Hilic)梯度洗脱,通过质谱的多反应监测(MRM)负离子模式扫描进行测定,外标法定量。结果表明:草甘膦、氨甲基膦酸的线性范围为0.02~0.2 μg/mL,相关系数(R²)分别为0.9995、0.9998,检出限分别为0.5 μg/kg和0.6 μg/kg,定量限分别为1.6 μg/kg和2.0 μg/kg;3个加标水平草甘膦的回收率在79.67%~96.17%之间,AMPA回收率在77.83%~99.47%之间,RSD值分别为3.95%~7.49%、1.96%~3.89%。与传统的柱前衍生方法相比,具有前处理简单、检出限低、灵敏度高的优点,完全可以适用于土壤中草甘膦的分析。     

郑州地区草坪根部病害病原种类鉴定及防治研究

通过实地调查、室内分离培养和病原鉴定 ,发现郑州市草坪根部病害的病原菌主要是禾德氏霉 (Drechsleragraminea)、立枯丝核菌 (Rhizoctoniasolani)、镰刀菌 (Fusariumspp .)、腐霉菌(Pythiumspp .)等。选用 10种不同杀菌剂对草坪根病优势病原菌室内毒力测定结果表明 ,烯唑醇和敌力脱对禾德氏霉、立枯丝核菌均有强烈的抑制菌丝生长的作用 ,对禾德氏霉的EC50 均为0 0 3μg/mL ,EC90 分别为 0 2 5 μg/mL和 0 98μg/mL ;对立枯丝核菌的EC50 分别为 0 11μg/mL和 0 4 7μg/mL ,EC90 分别为 78 0 6 μg/mL和 3 97μg/mL。五氯硝基苯对丝核菌也有较强的抑制作用。福美双对镰刀菌抑制作用较强。在小区防治试验中 ,对草坪根部病害效果较好的是12 5 %烯唑醇WP 10 0 0倍液、 4 0 %棉花保苗剂WP 5 0 0倍液、 4 0 %五氯硝基苯WP 5 0 0倍液和2 5 %敌力脱EC 10 0 0倍液 ,防治效果均在 5 0 %以上     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae

Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus.     

Breeding apomictic bahiagrass (Paspalum notatum Flügge) with improved turf traits

The development of a turf‐type bahiagrass could have a remarkable impact on the billion‐dollar turf industry in the south‐eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H²) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H² indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation.     

Inheritance of fruit colour in a wild Russian red raspberry seedling

Summary A new gene, i, from a self-incompatible wild Russian Rubus idaeus seedling is described. The gene i interacts with the fruit colour gene T, Tii plants having apricot instead of red fruits, and spines, leaves and stems pigmented to varying degrees. A deficit of apricot-fruited seedlings in progenies segregating for i could be explained by linkage between i and the self-incompatibility S locus with a crossover value of approximately 26.7%.Segregations for spine colour in crosses and backcrosses of the Russian seedling with two green-spined (ttII) raspberries selected for their yellow fruit colour, showed that both the latter carried the spine colour intensifier gene P. This suggests that earlier authors were incorrect in attributing the apricot fruit colour developed by some tt plants to a pleiotropic effect of P.     

Flag Leaf Senescence, as Evaluated by Numerical Image Analysis, and its Relationship with Yield under Drought in Durum Wheat

Senescence was evaluated at different stages of the grain‐filling period in eight durum wheat varieties using numerical image analysis (NIA). The varieties were grown under early, severe drought conditions on the high plains of Sétif in Algeria. After flowering, three different irrigation treatments were applied. Treatment effect was small, while a genotypic effect was noted for most of the senescence parameters. Senescence correlated to biomass, while the maximal rate of senescence, V_smax, correlated to thousand‐kernel weight. The potential of the method of numerical image analysis for monitoring flag leaf senescence, detecting genotypic variability and selecting genotypes with delayed senescence is discussed.     

Mechanisms and diversity of resistance to sorghum shoot fly,Atherigona soccata

Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums.     

Cowpea (Vigna unguiculata): Genetics,genomics and breeding

Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers.     

Screening for resistance to take-all in wheat,triticale and wheat-triticale hybrid lines

Summary Fifteen triticale and wheat-triticale hybrid lines were evaluated for resistance to the take-all fungus Gaeumannomyces graminis var. tritici and compared with five wheat and two rye lines in inoculated field and pot trials. The triticale and wheat-triticale hybrid lines varied in rye chromosome number and degree of resistance expressed. One line, Venus with seven pairs of rye chromosomes consistently showed levels of resistance intermediate between wheat and rye. A trend was observed where increasing rye chromosome content led to greater resistance but exceptions showed that variation within triticales could not be ascribed to rye chromosome content alone.     

Reaction of tritordeum to Fusarium culmorum and Septoria nodorum

Summary Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases.