NaHCO3胁迫对紫根水葫芦形态学指标和光合参数的影响

为研究NaHCO₃胁迫对紫根水葫芦的形态学指标及光合参数的影响,该文以紫根水葫芦为材料,采用不同浓度碱性盐NaHCO₃溶液处理成株紫根水葫芦,测定在NaHCO₃胁迫下紫根水葫芦的植株株高、根长、根冠比、生物量、含水量和光合参数[净光合速率(P_n)、胞间CO₂浓度(C_i)、蒸腾速率(T_r)、气孔导度(G_s)]。结果表明:紫根水葫芦在20 mmol·L^-1 NaHCO₃浓度下的水溶液pH值最为平缓; 在低浓度NaHCO₃溶液中(≤40 mmol·L^-1),相比CK,紫根水葫芦的形态学指标呈现增长或无显著影响情况,而在高浓度NaHCO₃溶液中(≥60 mmol·L^-1),随着NaHCO₃浓度的升高,紫根水葫芦形态学指标显著降低,且与NaHCO₃浓度呈负相关; NaHCO₃胁迫对紫根水葫芦的光合参数影响显著,随着NaHCO₃浓度的增加及试验处理时间的延长,紫根水葫芦的P_n呈持续下降的趋势,C_i、T_r和G_s整体呈上升趋势,其光合作用受到的主要是非气孔限制。综合分析显示,紫根水葫芦具有一定的耐NaHCO₃能力,能正常生存在不超过40 mmol·L^-1 NaHCO₃浓度的水体中,且能改善低NaHCO₃浓度下的水体pH值。     

镍离子对尖叶莴苣氮素吸收和生长生理的影响

以‘全年油麦菜’尖叶莴苣为试验材料,采用水培方式,研究3个浓度(0 mg·L^-1、0.1 mg·L^-1、1 mg·L^-1)Ni²⁺在22.4 mg·L^-1 N处理下对尖叶莴苣氮素吸收的生长及生理影响。结果显示：(1)尖叶莴苣根系和地上部生物量随处理时间的增加呈上升趋势。与对照T₁(0 mg·L^-1 Ni²⁺、112 mg·L^-1 N)相比,T₂处理(0 mg·L^-1 Ni²⁺、22.4 mg·L^-1 N)对尖叶莴苣根系及叶片生长具有一定抑制作用,植株鲜重、干重、根冠比、根系长度、平均直径、表面积、体积、根尖数、分根数、叶片表面积和体积在T3处理(0.1 mg·L^-1 Ni²⁺、22.4 mg·L^-1 N)下显著高于对照,T₄处理(1 mg·L^-1 Ni²⁺、22.4 mg·L^-1 N)对尖叶莴苣根系及其叶片生长具有一定促进作用,但对其根尖数和分根数表现出一定抑制性。(2)随着Ni²⁺浓度的增加,尖叶莴苣叶片叶绿素a、叶绿素b和总叶绿素含量呈先升后降的变化规律,且均在T₃处理下显著提高。(3)随着处理时间的增加,尖叶莴苣叶片的净光合速率(P_n)、气孔导度(G_s)和蒸腾速率(T_r)逐渐上升,胞间CO₂浓度(C_i)逐渐下降,且T₃处理叶片的G_s显著高于对照,其C_i最低,P_n最大。(4)施加Ni²⁺对尖叶莴苣有机酸、可溶性蛋白和可溶性糖含量以及SOD和POD活性有显著影响,在T₃处理下有机酸含量降低,可溶性糖和可溶性蛋白含量显著增加,SOD和POD活性显著提高。(5)T₃处理尖叶莴苣根系中N及叶片中B和Ca含量较高;根系中Ni含量高于叶片,T₃处理叶片中的Ni含量较低,Mg含量较高;植株体内Cu含量随Ni²⁺浓度增加而下降。研究表明,外源Ni²⁺处理能影响低氮条件下(22.4 mg·L^-1 N)尖叶莴苣幼苗生长及生理状况,适宜浓度(0.1 mg·L^-1)Ni²⁺可有效提高尖叶莴苣根系对氮素的吸收利用效率,减少氮素施用量,促进尖叶莴苣根系和地上部叶片生长,增加光合色素含量,并提高净光合速率,进而改善植株的产量和营养品质。     

草莓TCP转录因子家族生物信息学鉴定及基因表达分析

TCP转录因子家族是植物特异的一类调控逆境胁迫的重要转录因子。该研究利用生物信息学方法对草莓TCP转录因子家族成员进行鉴定,采用qRT PCR方法检测转录因子家族在非生物胁迫中的表达,并对相应转录因子家族基因的结构和功能进行了预测,为探究TCP转录因子在森林草莓非生物胁迫中的作用奠定基础。结果显示：(1)从森林草莓(Fragaria vesca)基因组和凤梨草莓(Fragaria ananassa)基因组中分别筛选了18个和58个TCP基因,并根据基因在染色体上的位置分别命名为FvTCP1~FvTCP18和FaTCP1~FaTCP58,亚细胞定位显示TCP家族基因主要位于细胞核上。(2)qRT PCR分析表明,森林草莓家族基因对逆境胁迫具有响应作用,但不同成员在不同胁迫处理下的响应程度存在差异,FvTCP14在200 mmol·L^-1 NaCl、10% PEG、100 μmol·L^-1 ABA、4 ℃低温、40 ℃高温和100 mmol·L^-1 H₂O₂处理下相对表达量极显著高于对照,分别是对照的43.78倍、166.73倍、38.39倍、265.87倍、626.24倍和451.85倍,表明^FvTCP14响应干旱、盐、ABA、H₂O₂、低温和高温胁迫;另外发现,FvTCP12在4 ℃低温、100 μmol·L^-1 ABA和100 mmol·L^-1 H₂O₂胁迫下与对照相比呈下调趋势,推测FvTCP12基因对低温、ABA和H₂O₂胁迫具有负调控作用。研究表明,森林草莓TCP转录因子在不同逆境胁迫中的表达存在一定的差异。     

水稻CPR5基因参与氧化胁迫响应

为探讨水稻(Oryza sativa L.)中CPR5 基因的功能,以其cDNA 文库为基础进行序列比对,并将1 个同源性较高的序列命名为OsCPR5.生物信息学分析表明,OsCPR5 的开放阅读框长度为1551 bp,编码516 个氨基酸.软件预测该编码蛋白可能是1 个具有5 个跨膜区的膜蛋白和核定位蛋白.组织表达和亚细胞定位分析表明,OsCPR5 在根中的表达水平较高,且广泛分布在细胞膜、细胞质和细胞核上.逆境胁迫分析实验表明,植物激素脱落酸(Abscisic acid, ABA)、过氧化氢(Hydrogen peroxide,H₂O₂)、氯化钠(NaCl)、甲基紫精(Methyl viologen, MV)等环境胁迫可诱导OsCPR5 的上调表达,其中氧化胁迫相关的MV 和H₂O₂ 处理效果最为明显.拟南芥(Arabidopsis thaliana)转基因株系atcpr5/OsCPR5 在浓度为0.5 μmol L^-1、 1.0 μmol L^-1 的MV以及6 mmol L^-1、 8 mmol L^-1 的H₂O₂ 处理下,种子萌发率明显高于atcpr5 突变体.这揭示了OsCPR5 基因在植物抗氧化胁迫响应中具有一定的作用.     

浓度NO对高表达转玉米C4型pepc水稻光合的促进

为了揭示C₃植物中C₄ pepc高表达带来的生理差异与其高光合效率的关系。本文以高表达的转玉米C₄ pepc光合基因水稻（PC）及原种Kitaake(WT）为材料,通过水培在孕穗期通过根吸入的方法,进行不同浓度的NO供体、NO合成抑制剂以及相关影响信号分子的试剂单独和联合过夜处理12 h,选取倒二叶研究NO对供试材料净光合速率（P_n）,气孔导度(G_s)和胞间CO₂浓度(C_i)的影响。结果表明：WT和PC在200 μmol·L^-1 SNP（Sodium nitroprusside）和1 mmol·L^-1 L-Arg(L-Arginine)处理下,P_n分别增加20.8%、10.7%,差异显著（p<0.05）;随SNP和L-Arg浓度的增加,其表现不同程度的抑制,与PC相比,WT的P_n抑制更显著（p<0.05）,而G_s和C_i的变化则相反（p<0.05）;进一步结合200 μmol·L^-1 SNP和1 mmol·L^-1 L-Arg与SA处理,结果与高浓度的NO供体处理类似;在联合6 mmol·L^-1 Ca²⁺螯合剂EGTA处理下,与PC相比,WT的P_n抑制达到极显著水平（p<0.01）,C_i的变化则相反（p<0.05）。相关分析结果表明：PC的P_n的高低与G_s的相关性小于WT,PC与WT决定系数分别为0.654 9、0.773 5;而与C_i的相关性则更大些,PC与WT决定系数分别为0.466 5、0.419 6,显示PC可能有不同的调节方式,尤其在低浓度的NO,PC可在Ca²⁺参与下调节气孔的开放,在气孔关闭的条件下,仍能维持一定的P_n。     

γ-氨基丁酸(GABA)种子引发缓解辣椒盐胁迫的效果及生理生化的变化

种子引发是提高作物生长期耐盐性的有效方法,而γ-氨基丁酸(GABA)种子引发对辣椒(Capsicum annuum)耐盐性的效果和作用机制尚不清楚。该研究以‘茂蔬360''朝天椒为材料,分析了不同浓度γ-氨基丁酸(0、1.0、2.0、4.0、6.0、8.0 μmol·L^-1)种子引发对4～6叶期100 mmol·L^-1 NaCl胁迫下的植株生物量、渗透调节物质、抗氧化能力、光合作用系统及钾钠离子吸收的影响。结果表明:(1)种子引发能显著增加盐胁迫下辣椒植株的生物量,以6.0 μmol·L^-1 GABA引发处理的效果最佳。(2)种子引发处理增加了盐胁迫下植株的可溶性糖、可溶性蛋白及脯氨酸的含量,同时,O₂^-和MDA的含量下降,抗氧化酶(SOD、POD、CAT和APX)活性增强,叶片叶绿素含量增加,叶片叶绿素荧光参数受胁迫影响程度低,叶绿素荧光指标包括F_v ''/F_m ''、qP_Lss、QY_Lss、NPQ_Lss和Rfd均有所上升。根、茎中的K⁺含量和K⁺/Na⁺比值下降。(3)灰色关联度分析表明,GABA种子引发主要通过提高POD、CAT的活性和渗透调节物质含量来缓解盐胁迫对辣椒植株的伤害。综上所述,6.0 μmol·L^-1 GABA种子引发可有效提高辣椒苗期的耐盐性,其作用机制可能是提高了盐胁迫下辣椒植株的抗氧化能力和渗透调节能力。     

氧化铈纳米颗粒种子引发对盐胁迫下辣椒种子萌发及幼苗生长的影响

氧化铈纳米颗粒(CeO₂NP_S),因具有较强的自由基清除能力和抗氧化酶特性,已被证明可提高植物的耐盐性,但其对辣椒种子引发作用和机制尚不明确。为揭示CeO₂NP_S种子引发处理辣椒对盐胁迫下的萌发及幼苗生长的影响,以辣椒品种(Capsicum annuum)茂蔬360为试验材料,设置了7个CeO₂NP_S浓度(0、0.05、0.1、0.2、0.3、0.4、0.5 mmol·L^-1),以未引发处理组为对照,研究不同浓度CeO₂NP_S种子引发处理后对盐胁迫下辣椒种子萌发、幼苗生物量和生理生化指标的影响。结果表明:(1)0.5 mmol·L^-1 CeO₂NP_S种子引发处理后的种子,其可溶性蛋白质、脯氨酸含量和过氧化氢酶(CAT)活性、抗坏血酸(AsA)含量和AsA/DHA比值显著提高,超氧阴离子(O₂^-)含量显著降低; 盐胁迫下,该处理种子的发芽率、发芽势、发芽指数、活力指数最大。(2)0.4 mmol·L^-1 CeO₂NP_S种子引发处理的幼苗在盐胁迫下的鲜重、干重和根长最大,幼苗的可溶性蛋白质、AsA含量和AsA/DHA比值均显著提高。综上认为,CeO₂NP_S引发处理不仅可通过降低种子水势、促进贮藏物质代谢和提高抗氧化能力提高种子在盐胁迫下的发芽率,还可在苗期通过增强蛋白合成和抗坏血酸-谷胱甘肽循环(AsA-GSH)促进盐胁迫下幼苗的生长。     

盐分胁迫下杠柳叶片光合特性的光响应研究

利用CID型便携式光合作用仪测定不同NaCl浓度下杠柳叶片净光合速率(P_n)、蒸腾速率(T_r)、气孔导度(G_s)、水分利用效率（WUE）及光能利用率(LUE)生理参数的光响应过程,阐明盐分胁迫下其对光照响应的规律,探讨有利于杠柳正常生长的盐分浓度和光照条件。结果表明:（1）各盐分浓度下杠柳叶片光补偿点（LCP）在21.89～65.05 μmol·m^-2·s^-1之间变动,介于阴性植物与阳性植物之间;杠柳随土壤盐分的不同,其光合作用参数对光照强度表现出一定的适应性和可塑性;50 mmol·L^-1盐分浓度下杠柳光合同化能力最强,最有利于其干物质的积累,表现出一定的耐盐性。（2）轻度的盐分胁迫（小于50 mmol·L^-1）可以提高杠柳叶片的P_n、G_s、WUE和LUE,而盐分胁迫对杠柳的T_r有抑制作用,并随着盐分浓度的增加其抑制作用愈强烈。（3）维持杠柳正常生长的土壤盐分浓度小于50 mmol·L^-1,最佳PAR为1 000～2 000 μmol·m^-2·s^-1;而保持杠柳最大WUE和LUE的光照强度分别为800和100 μmol·m^-2·s^-1。     

NaHCO3胁迫对三色堇生长及抗逆生理特性的影响

以三色堇实生苗为材料,设置不同浓度的NaHCO₃［0(CK)、25、50、100、150和200 mmol·L^-1］处理,在胁迫后第7天和第14天分别测定各处理幼苗叶片的渗透调节物质含量、抗氧化酶活性、叶绿素含量、丙二醛(MDA)含量以及株高生长量,探讨三色堇对NaHCO₃胁迫的生理响应机制。结果表明：(1)三色堇株高生长量在NaHCO₃浓度小于等于50 mmol·L^-1时较CK显著增加,在100 mmol·L^-1时与CK相近,在大于100 mmol·L^-1时较CK显著降低。(2)各浓度处理三色堇叶片可溶性糖(SS)、可溶性蛋白(SP)、游离脯氨酸(Pro)含量在胁迫第7天均显著高于CK;而胁迫第14天时,各浓度处理的SS含量、50 mmol·L^-1处理的SP含量以及150、200 mmol·L^-1处理的Pro含量仍显著高于CK。(3)胁迫第7天时,三色堇叶片超氧化物歧化酶(SOD)活性在各胁迫浓度下较CK均显著增强,但其过氧化物酶(POD)、过氧化氢酶(CAT)活性均无显著变化;胁迫第14天时,各浓度处理的CAT活性、50 mmol·L^-1处理的POD活性以及100、150 mmol·L^-1处理的SOD活性均显著高于相应CK。(4)在NaHCO₃胁迫过程中,三色堇叶片MDA含量均随着胁迫浓度增加而逐渐增加,且均显著高于CK。(5)三色堇叶片的叶绿素含量在胁迫第7天时均无显著变化,胁迫第14天时也仅在150或者200 mmol·L^-1处理下较CK显著降低。研究发现,三色堇植株能耐受小于等于100 mmol·L^-1NaHCO₃胁迫,NaHCO₃对株高生长有低浓度促进、高浓度抑制的剂量效应;三色堇在NaHCO₃胁迫期间能够通过增加渗透调节物质含量、增强抗氧化酶活性来缓解胁迫诱导的过氧化伤害,一定程度上提高了幼苗的耐受能力。     

厌氧氨氧化菌混培物生长及代谢动力学研究1

研究了厌氧氨氧化菌混培物的动力学特性。测得细胞产率系数1.573mgVS(mmol NH⁺₄)^-1;细胞衰减常数0.052mgVS(g·VS·d)^-1。厌氧氨氧化菌混培物的最大氨氧化速率1.320～2.761mmol(gVS·d)^-1,最大亚硝酸盐转化(反硝化)速率14.497mmol(gVS·d)^-1。厌氧氨氧化菌混培物利用氨的Km值1.801～4.215mmol·L^-1,利用亚硝酸盐的Km值0.468mmol·L^-1。氨自身的抑制常数38.018～98.465mmol·L^-1,实际最大氨氧化速率的氨浓度16.656mmol·L^-1。亚硝酸盐对厌氧氨氧化的抑制常数5.401～11.995mmol·L^-1。厌氧氨氧化的最适pH7.605。厌氧氨氧化的最适温度30℃。V_maxa、K_ma、K_ia和K_in的活化能依次为37.316、30.239、33.695和30473kJ·mol^-1。     

Comparative study of Bifidobacteriumanimalis, Escherichiacoli, Lactobacilluscasei and Saccharomycesboulardii probiotic properties

The present work investigates some probiotic properties of four different microorganisms (Bifidobacterium animalis var. lactis BB-12, Escherichia coli EMO, Lactobacillus casei and Saccharomyces boulardii). In vitro and in vivo tests were carried out to compare cell wall hydrophobicity, production of antagonistic substances, survival capacity in the gastrointestinal tract of germ-free mice without pathological consequence, and immune modulation by stimulation of Küpffer cells, intestinal sIgA and IL-10 levels. In vitro antagonism against pathogenic bacteria and yeast was only observed for the probiotic bacteria B. animalis and L. casei. The hydrophobic property of the cell wall was higher for B. animalis and E. coli EMO, and this property could be responsible for a better ability to colonize the gastrointestinal tract of germ-free mice. Higher levels of sIgA were observed mainly for S. boulardii, followed by E. coli EMO and B. animalis, and only S. boulardii induced a significant higher level of IL-10. In conclusion, for a probiotic use, S. boulardii presented better characteristics in terms of immunomodulation, and B. animalis and L. casei for antagonistic substance production. The knowledge of the different probiotic properties could be used to choice the better microorganism depending on the therapeutic or prophylactic application.     

Effects of MULTIFOLIATE-PINNA, AFILA, TENDRIL-LESS and UNIFOLIATA genes on leafblade architecture in Pisum sativum

In order to dissect the genetic regulation of leafblade morphogenesis, 16 genotypes of pea, constructed by combining the wild-type and mutant alleles of MFP, AF, TL and UNI genes, were quantitatively phenotyped. The morphological features of the three domains of leafblades of four genotypes, unknown earlier, were described. All the genotypes were found to differ in leafblade morphology. It was evident that MFP and TL functions acted as repressor of pinna ramification, in the distal domain. These functions, with and without interaction with UNI, also repressed the ramification of proximal pinnae in the absence of AF function. The expression of MFP and TL required UNI function. AF function was found to control leafblade architecture multifariously. The earlier identified role of AF as a repressor of UNI in the proximal domain was confirmed. Negative control of AF on the UNI-dependent pinna ramification in the distal domain was revealed. It was found that AF establishes a boundary between proximal and distal domains and activates formation of leaflet pinnae in the proximal domain.     

Presence of Rhizobium Etli bv . Phaseoli and Rhizobium Gallicum bv . Gallicum in Egyptian Soils

Seven bean rhizobial strains EBRI 2, 3, 21, 24, 26, 27 and 29 identified as Rhizobium etli, and EBRI 32 identified as Rhizobium gallicum, isolated from Egyptian soils and which nodulated Phaseolus vulgaris efficiently, were subjected to hybridization with a nifH probe in order to estimate the copy number of this gene. Seven strains (EBRI 2, 3, 21, 24, 26, 27 and 29) which were only able to nodulate Phaseolus vulgaris, contained three copies of the nifH gene, consistent with their identification as Rhizobium etli bv. phaseoli. Only one strain (EBRI 32) which nodulated both Phaseolus vulgaris and Leucaena leucocephala, had one copy of nifH gene. This confirmed the classification of this strain as Rhizobium gallicum bv. gallicum.     

Analysis of urinary N-acetyl-S-(N-methylcarbamoyl)cysteine, the mercapturic acid derived from N,N-dimethylformamide

Human biotransformation of the industrial solvent N,N-dimethylformamide gives raise to N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) which has the longest half-life (about 23 h) among urinary metabolites of N,N-dimethylformamide. It could be used for monitoring industrial exposure over several workdays, by measuring it in urine samples collected at the end of the working week. This is consistent with the suggestions of the American Conference of Governmental Industrial Hygienists, which established a limit of 40 mg/l for the year 2000. An easy, cheap and user-friendly method has been developed for determination of urinary AMCC. Unlike currently available methods, it requires neither a time-consuming preparation phase nor gas chromatographic analysis with a nitrogen-phosphorus or mass detector. The method uses high-performance liquid chromatography (HPLC), with an UV detector at 436 nm. A 10-μl volume of urine is added to a carbonate–hydrogen carbonate buffer and mixed with a dabsyl chloride solution in acetonitrile. The reaction between AMCC and the reagent is performed at 70°C for 10 min. The ‘dabsylated’ product is stable for at least 12 h. After brief centrifugation, the solution is ready for HPLC analysis using a C₁₈ column (250×4.6 mm, 5 μm). The method is sensitive (detection limit 1.8 mg/l) and specific. It identified urinary AMCC in urine of 40 subjects not exposed to N,N-dimethylformamide with a median concentration of 3.9 mg/l. In urine samples from 20 workers exposed to N,N-dimethylformamide (5–40.8 mg/m³), AMCC concentrations ranged from 16 to 170 mg/l. Industrial toxicology laboratories with limited instrumentation will be able to use it in the biological monitoring of workers exposed to N,N-dimethylformamide.     

Non-specificity of a colorimetric method for the estimation of N-acetyl-d-glucosamine

The colorimetric method of Reissig et al. for the estimation of N-acetylamino sugars, is often used as a specific method for the quantification of the N-acetyl-d-glucosamine. Although this assay is more sensitive to the monomer, it recognizes all soluble N-acetyl-d-glucosamine oligomers. This result is very important because this method is extensively used in biology for the estimation of chitinolytic activity.     

Characterisation of cell wall polysaccharides, arabinogalactans-proteins (AGPs) and phenolics of Cola nitida, Cola acuminata and Garcinia kola seeds

Many Cola plant species are endemic to West and Central Africa. Cola acuminata and Cola nitida are used as masticatory when fresh, while the dried nuts are used for beverages and pharmaceutical purposes in Europe and North America. Garcinia kola seeds, that serve as a substitute for the true kola nuts, are used in African traditional medicine for the treatment of various diseases, including colic, headache and liver cirrhosis. Seeds extracts of G. kola are also known for their anti-inflammatory, antimicrobial and antiviral properties. To gain information on the chemical properties of the kolas, we have isolated and analyzed cell wall polysaccharides, arabinogalactan-proteins and phenolic substances from the seeds of the three kola species. The sugar composition of cell wall material of C. acuminata, C. nitida and G. kola revealed that Gal (up to 30%), Ara, GalA and Glc as the predominant monosaccharides, representing approximately 90% by mol of the total hydrolysable sugar present in this material. In Ammonium oxalate cell wall fraction, GalA was found to be the major sugar present in all kola species. In the alkali-soluble fraction, there were significant differences in the level of Glc and Gal. The level of Glc was high in C. acuminata and C. nitida while the level of Gal and Xyl were high in C. nitida and G. cola. Isolation and quantification of arabinogalactan-proteins demonstrate that G. kola seeds contained four to eight times more of these proteoglycans than the seeds of the other two species. Finally, analysis of soluble phenolic substances shows that caffeine and catechin were largely represented in C. acumina and C. nitida seeds, with caffeine accounting for 50% of all soluble phenolics. These findings indicate that the three Kola seeds are highly enriched in pectins and proteoglycans and that C. acuminata and C. nitida can be used as a possible source of caffeine and catechin.     

中国黑粉菌属和利罗黑粉菌属

黑粉菌属是Roussel 1806年建立的,全世界记载有三百余种,主要寄生于禾本科,是经济作物及牧草的重要致病菌·长期以来,对黑粉菌的邢子使用过各种名称,如厚垣孢子,冬孢子及黑粉孢子等.本文采用黑粉孢子以区别锈菌的冬孢子. 芳’(1979)在《中国真菌总汇》中列出黑粉菌属五十种及一个变型.作者经过显微结构和超显微结构的研究,承认其中二十九种为正确名称,八种及一变型为异名,顶黑粉菌(Ustilago acrearus Berk.)由于错拼而被废弃.埃地黑粉菌(Ustilago emodensis Berk.)被转移至利罗粉菌属(Liroa).另有十一种黑粉菌因缺少标本留待今后订正.自1979年以后,杨信东(1983)增加黑粉菌属二种我国新纪录,K.范基和郭林(1986)描述一新种,四种新纪录.在本文中,作者描述一新种:鸢尾蒜黑粉(Ustilago ixiolirii Guo L) ,孢子堆生在蒴果内,不开裂,黑色,粉末状.黑粉孢子球形,近球形,稀椭圆形, 12.5-21×10-21μm,黑褐色,壁厚1-1.Sμm,纹饰脑状.是迄今生在石蒜科植物上唯一黑粉菌的种,其它几种黑粉菌均属条黑粉菌属.本文增加七种我国新纪录.共计四十九种,寄生于六科四十四属植物,主要是禾本科和蓼科.这仅是黑粉菌属研究的初步报告,在全国范围内大量采集黑粉菌标本后,作者相信会有更多新种和我国新纪录被发现.利罗黑粉菌属(Liroa)是从黑粉菌属(Ustaligo)分出的,此属为单种属.     

转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响

【目的】为探究转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育及其捕食功能的影响。【方法】以转Cry1Ac/1Ab基因棉与其亲本常规棉为实验材料,利用取食不同棉花品种叶片的棉铃虫饲喂异色瓢虫幼虫。【结果】与常规亲本棉相比,取食饲喂转基因棉花叶片的初孵棉铃虫幼虫的异色瓢虫幼虫从1龄发育至化蛹期时间延长0.77 d,但差异不显著;除1龄幼虫体重增加(0.0773 mg)外,其余各龄期幼虫体重均有所下降,但差异均不显著;异色瓢虫1、2、3、4龄幼虫对初孵棉铃虫捕食量均随棉铃虫密度的增加而增加,捕食功能反应均符合HollingⅡ圆盘方程。【结论】转Cry1Ac/1Ab基因棉花对异色瓢虫生长发育无显著影响,饲喂取食转Cry1Ac/1Ab基因棉花的棉铃虫对异色瓢虫捕食功能无显著差异。     

Nomenclatural changes resulting from the transfer of tropical African Sarcostemma to Cynanchum ( Apocynaceae : Asclepiadoideae )

Summary  Four species of tropical African Sarcostemma are transferred to Cynanchum together with two subspecies of S. viminale. In addition, Sarcostemma mulanjense is reduced to subspecific rank under C. viminale.