红托竹荪矿质元素和氨基酸需求特性研究

本研究以原生境中红托竹荪主要伴生植物竹子的根茎叶蔸作为培养基质,结合根、茎、叶、蔸中矿质元素和氨基酸含量分析,通过菌丝宏观形态评价,得到与红托竹荪菌丝生长相关的物质,并进一步采用单因素实验分别验证。结果表明,4种矿质元素(Ca、Mn、Zn和Fe)及6种氨基酸(天冬酰胺、天门冬氨酸、谷氨酸、丙氨酸、苏氨酸和丝氨酸)与红托竹荪菌丝生长速度和长势呈正相关;在基础培养基中四种矿质元素最适添加浓度分别为：Zn²⁺、20μmol/L,Fe³⁺、100μmol/L,Mn²⁺、100μmol/L,Ca²⁺、10 mmol/L;6种氨基酸的最适添加浓度分别为：D-丙氨酸为10 mg/L、DL-丝氨酸为10 mg/L、L-苏氨酸为100 mg/L、L-谷氨酸为100 mg/L、L-天门冬氨酸为1 mg/L和L-天冬酰胺为100 mg/L。     

高山羊齿孢子的组织培养

[目的]探讨不同灭菌方式对组织培养中高山羊齿孢子成活率的影响以及不同培养基对孢子萌发率的影响.[方法]利用NaClO、NaClO+酒精、升汞、升汞+酒精、升汞+NaClO、酒精这6种不同灭菌方式研究其对高山羊齿孢子成活率的影响;考虑4因素基本培养基、蔗糖、NAA、6-BA进行L16 (44)正交设计,研究其对高山羊齿孢子萌发率的影响.[结果]6种灭菌处理中,NaClO+酒精的灭菌效果最好;酒精的灭菌效果最差;在正交实验中,以1/2 MS+3％蔗糖+1 mg/L 6-BA+0.1 mg/L NAA为高山羊齿孢子萌发的最佳培养基,萌发率达63.69％,以不加任何激素的MS培养基中萌发率最低.[结论]2种不同的灭菌剂混合使用比单独使用灭菌剂的效果好;基本培养基对高山羊齿孢子萌发率的影响最大,影响顺序为:基本培养基＞6-BA＞蔗糖＞NAA.     

微波消解-ICP-AES法测定苹果干制品中铅镉砷含量的研究

采用微波消解-电感耦合等离子体发射光谱法测定苹果干制品中铅、镉、砷的含量。经试验优化而确定的微波消化条件为加入2 m L浓硝酸,电热板温度86℃,预消化30 min,放冷至室温后加入1 m L双氧水,盖好盖子,装好罐,微波消化,定容后用ICP-AES检测。经分析,该方法回收率好,为93%~104%。从测定的结果可看出,苹果干制品中重金属含量为Pb0.2 mg/kg,Cd0.1 mg/kg,As0.2 mg/kg,为苹果干制品产品标准的制定提供依据。     

三种单链特异性核酸酶检测桉树ESTP的酶切条件优化

单链特异性(SSS)核酸酶是基因组学研究的有效工具.本研究对绿豆芽核酸酶、S1和芹菜汁提取物三种SSS核酸酶检测桉树ESTP检测的酶切条件进行了优化,优化因子依次包括Mg2 浓度、酶切温度、酶用量和/或pH值等因子.三种酶的最适酶切温度均为60℃.绿豆芽核酸酶优化后的酶切反应体系为:10×Buffer(pn 5.56)1.0 μL(NaAc 300 mmol/L,Nacl 1.0 mol/L,ZnAc2 10 mmol/L,甘油50%,MgCl2 100 mmol/L),PCR产物5 μL,酶4.5 U,超纯水补至10 μL;S1的优化酶切体系为:10×Buffer(pH 5.46～3.67)1.0 μL(MgCl2100 mmol/L,ZnAc2 2 mmol/L,Bis-Tris 200 mmol/L,Triton X100 0.02%,BSA 0.002 mg/mL),PCR产物5 μL,S1酶5 U,超纯水补至10 μL;CJE的优化酶切体系为:10×Buffer(pH 7.5)1.0 μL(MgCl2 100 mmol/L,Hepes100 mmol/L,KCI 100 mmol/L,Triton X100 0.02%,BSA 0.002 mg/mL),PCR产物5.0 μL,CJE酶1.0 μL,超纯水3.0 μL.综合考虑酶切效果和成本,推荐S1为检测桉树ESTP的经济、有效的SSS核酸酶.     

不同热力杀菌方式对番木瓜果汁挥发性香气成分的影响

以海南"Dwarf solo"番木瓜原果汁及经巴氏灭菌、超高温瞬时灭菌(UHT)处理后的果汁为原材料,应用顶空固相微萃取-气相色谱质谱联用技术测定、分析其挥发性香气成分。结果表明,三种果汁检测到香气物质种类分别为38种、47种、39种,总含量分别为3 486.01、3 403.61、4 072.05μg/L。原果汁中异硫氰酸苄酯含量最高,达1 552.2μg/L。经过巴氏灭菌的果汁中具有陈腐味的L-α-松油醇含量升高了约100倍,癸酸由2.38μg/L增加到85.49μg/L,此外还新产生不良嗅感的辛酸、苯乙醛。经过UHT灭菌的果汁挥发性成分种类与原果汁相比变化较小,具有苦杏仁味的苯甲醛含量增加了近440μg/L。巴氏灭菌对番木瓜果汁挥发性成分破坏较大,UHT灭菌能较好的保持果汁原有风味。     

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.     

沉积物中生物活性磷赋存形态对耗氧有机物的响应

[目的] 本研究为验证耗氧有机物影响沉积物中生物活性磷的赋存形态的假说。[方法]以葡萄糖代替耗氧有机物,将沉积物暴露于耗氧有机物30天。[结果表明] 不充气时,葡萄糖浓度0、2、4、8 mg/L下的表层沉积物Ex-P含量为0.02±0.01、0.02±0.01、0.03±0.01、0.02±0.01 μmol/g;充气时,相应葡萄糖浓度下的表层沉积物Ex-P含量为0.03±0.00、0.03±0.01、0.03±0.01和0.06±0.02μmol/g,葡萄糖浓度8mg/L下的Ex-P含量高于葡萄糖浓度0mg/L下的（P< 5%）。不充气时,葡萄糖浓度0、2、4和8mg/L 下的表层沉积物IP含量为0.96±0.42、0.74±0.29、0.97±0.78和0.88±0.22μmol/g;充气时,相应葡萄糖浓度下的表层沉积物IP含量为0.37±0.10、0.46±0.16、0.41±0.06和0.69±0.05μmol/g,葡萄糖浓度8mg/L下的IP含量高于葡萄糖浓度0mg/L下的（P< 5%）。[结论]耗氧有机物对沉积物中生物活性磷有双重阈值作用。     

高效液相色谱法直接拆分和测定酸奶中的乳酸手性对映体

为了快速高效分析酸奶中的乳酸含量,研究一种新的高效液相法和手性分离柱对手性对映体L -乳酸和D -乳酸测定的方法。该检测系统配备了二极管阵列检测器的高效液相系统,检测波长为254 nm,色谱柱为手性柱Chirex 3126（D）- penicillami（4.6 mm ID×250 mm L,5μm）,流动相为0.002 mol/L CuSO4溶液（含5%异丙醇）。L -乳酸和D -乳酸的保留时间分别为25.496 min和32.864 min,4种浓度L -乳酸和D -乳酸混标保留时间的RSD为0.80%~1.30%;6次重复进样酸奶样品的L -乳酸和D -乳酸保留时间的RSD都为0.42%,L -乳酸含量的RSD为0.74%,D -乳酸含量的RSD为1.04%;在酸奶样品中加标样检测L -乳酸和D -乳酸的回收率分别为99.4%和95.0%,保留时间的RSD分别为0.20%,0.60%。将此法用于10种市售酸奶产品的检测,酸奶中L -乳酸的含量为25.00~100.00 g/L,D -乳酸的含量为0~2.00 g/L,L -乳酸的百分比在97%以上。综上所述,此法能用于分析酸奶中L -乳酸和D -乳酸,回收率高,精密度和准确性好。     

纳他霉素结合1-MCP处理冬枣果实的耐贮性研究

探讨纳他霉素结合1-MCP处理对冬枣果实耐贮性的影响,以促进其产业健康、可持续发展.以湖南地区冬枣为试材,果实经0.5、1.0 mg/mL纳他霉素结合1.0 μL/L 1-MCP处理后于(4±1)℃条件下进行贮藏,同时以蒸馏水喷施为对照(CK).结果表明,贮藏90 d时,与CK相比,1.0 mg/mL纳他霉素结合1.0 μL/L 1-MCP处理组的好果率提高了 58.82％,失重率减少了 28.63％,VC含量提高了46.28％,前期还原糖、可溶性固形物含量的增加量及游离酸的降低量有所减缓;同时在峰值时期,果实果胶酶、淀粉酶活性以及呼吸、乙烯释放量有所降低,而SOD和CAT活性有所升高,且均具有显著性差异(P＜0.05).总体上,0.5或1.0 mg/mL纳他霉素结合1.0 μL/L 1-MCP处理对提高冬枣果实耐贮性的效果明显.纳他霉素与1-MCP结合作为一种新型防腐鲜剂为冬枣果实长期高效、绿色、环保贮藏提供了方向,具有一定实际意义.     

外源赤霉素对盐胁迫下番茄种子萌发和幼苗生长的影响

以SH 19-4和SH 19-6两个番茄品种为材料,进行不同梯度盐浓度胁迫,同时施加不同浓度的赤霉素,分别测定发芽率、发芽势、发芽指数等指标,观察外源赤霉素对盐胁迫下番茄种子萌发和幼苗生长的影响.结果表明,在所设盐浓度梯度范围内,外源施加20 μmol/L、50 μmol/L、100 μmol/L的赤霉素处理后,番茄种...     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.