防烟叶霉变菌株对烟叶霉变的影响

为有效防止烟叶霉变,采用平板对峙培养的方法,就3个防烟叶霉变菌株对霉变菌的抑制作用进行了研究．结果表明,JMBl42、B112、B329对供试霉变菌皆表现出一定的抑制作用,对不同霉变菌的平均抑制率分别为51．6％、52．9％、53．7％．3个防烟叶霉变菌株分别以每mL 10^7、10^8、10^9 cfu(colony当当forming unit)13个浓度单独处理和每mL10。cfu浓度混合处理烟叶,结果表明,JMBl42菌株每mL10,cfu处理浓度效果最好,与对照差异极显著,其次为B112菌株每mL10^8cfu处理浓度,但它与对照差异不显著,B329菌株处理效果最差,混合施用结果与对照差异不显著．由此确定JMBl42菌株每mL10^9cfu处理浓度为仓储烟叶防霉变最佳处理参数、     

哈茨木霉的培养及其对烟草疫霉生长的抑制研究*

哈茨木霉是一类重要的植病生防因子。哈茨木霉TH-1分别在PDA培养基、麦芽糖培养基、查氏培养基和琼脂培养基上培养均能产孢,其中PDA培养基为最适培养基。PDA培养基上,菌丝生长适宜温度27.5℃~35℃,最适温度32.5℃,产孢最适温度27.5℃。菌丝生长适宜pH值为3~7,产孢适宜pH值为5~9,生长与产孢最适pH值为5。光照对菌丝生长影响不大但明显影响菌株的产孢数量,光照时间越长产孢量越大。对峙培养试验表明TH-1明显抑制疫霉菌的生长速率,其无菌滤液明显抑制烟草疫霉菌游动孢子的萌发,并抑制游动孢子芽管     

哈茨木霉的培养及其对烟草疫霉生长的抑制研究

哈茨木霉是一类重要的植病生防因子。哈茨木霉TH-1分别在PDA培养基、麦芽糖培养基、查氏培养基和琼脂培养基上培养均能产孢,其中PDA培养基为最适培养基。PDA培养基上,菌丝生长适宜温度27．5℃～35℃,最适温度32．5℃,产孢最适温度27．5℃。菌丝生长适宜pH值为3～7,产孢适宜pH值为5-9,生长与产孢最适pH值为5。光照对菌丝生长影响不大但明显影响菌株的产孢数量,光照时间越长产孢量越大。对峙培养试验表明TH-1明显抑制疫霉菌的生长速率,其无菌滤液明显抑制烟草疫霉菌游动孢子的萌发,并抑制游动孢子芽管的伸长,TH-1对游动孢子萌发的相对抑制率为12．7％,对芽管生长长度的相对抑制率为63．1％。水解酶平板活性测定显示,TH-1产生β-1,3葡聚糖酶与纤维素酶,从而使烟草疫霉菌细胞壁的消解,产生非挥发性抗生素抑制烟草疫霉菌孢子萌发,但对菌丝生长影响不大。     

柑桔全爪螨高致病力菌株芽枝状枝孢霉的生物学特性研究

【目的】明确柑桔全爪螨Panonychus citri(Mc Gregor)高致病力菌株芽枝状枝孢霉Cladosporium cladosporioides(CQBBW3)的生物学特性。【方法】通过单因素试验,测试了不同培养基、碳源、氮源、温度及pH对CQBBW3菌株生长和产孢的影响。【结果】CQBBW3菌株的LC50为4.66×108个孢子/m L,LT50为6.2353 d。最佳生长培养基是淀粉琼脂培养基,最适产孢培养基为察氏培养基;菌丝生长最适碳源和氮源为甘露醇和甘氨酸,产孢最适碳源和氮源为乳糖和赖氨酸;最适生长温度为25℃,最适产孢温度为15℃和30℃;最适生长pH值为6.0~8.0,最适产孢pH值7.0。【结论】CQBBW3菌株对柑桔全爪螨有较好的杀虫活性,喜好25℃、中性、富含有机营养的环境。本研究为菌株快速培养及其真菌杀虫制剂的开发与田间应用奠定基础。     

耐盐碱菌株的分离筛选及生物学特性和盐碱去除效率的研究

将采集于黑龙江省大庆市盐碱地的土壤样品经适当稀释后,涂布于高盐碱的培养基中,分离纯化获得41株菌。经过不断分别或同时提高培养基的盐、碱浓度进行耐盐碱菌株的筛选,获得1株耐盐碱菌株7,其在pH值13且盐(NaCl)浓度达到200g.L-1的培养基中仍可生长,该菌株既属于极端嗜盐微生物又属于极端嗜碱微生物。分别于不同碳源、氮源、碳氮比、初始pH值和培养温度条件下,对菌株7的生物学特性和盐、碱去除能力进行研究。结果表明,该菌株生长和去除盐碱的最佳碳源为牛肉膏;最佳氮源为蛋白胨;碳氮比为4:1时,最有利于菌株的生长和对盐、碱的去除;菌株生长的最适初始pH值为9.5,最适温度为20℃,而盐、碱去除的最佳温度则为30～35℃。     

一株产高温蛋白酶嗜热菌A-2的筛选鉴定及酶学特性分析

本研究为从云南腾冲热泉中分离纯化得到一株产高温蛋白酶的菌株并对其进行驯化培养,用以探究该菌株的生长条件及酶学特性,通过选择培养基筛选能够分解脱脂奶粉产蛋白酶的菌株,应用常规方法液体培养菌体,探究温度、pH、碳源、氮源对菌株生长情况的影响,并采用福林酚法测蛋白酶活性。并提取蛋白酶液对酶的最适pH、温度以及热稳定性、pH稳定性进行研究。结果发现通过含脱脂奶粉的固体培养基筛选得到一株产蛋白酶菌株A-2,经过生理生化试验和16S rDNA鉴定知该菌种属于Aneurinibacillus属。酵母粉、葡萄糖、55℃、pH值7.5分别为菌株生长的最适氮源、碳源、温度和pH。此外该菌株所产的蛋白酶最适温度为60℃,在pH值7~9具有较好的酶活性。因此,该菌株为嗜热芽孢杆菌,所产的碱性蛋白酶具有较高的耐受温度和pH稳定性,为进一步开发利用提供参考的价值。     

节杆菌PJ3降解咔唑和联苯

菌株PJ3经16SrDNA鉴定为节杆菌(Arthrobacter sp.),同源树表明,该菌株与已报道咔唑降解菌株IC177同源关系最近,其次是联苯降解菌株K37和R04。为了明确PJ3菌株对咔唑和联苯的降解能力,在PJ3生长的最适pH值进行优化的基础上,利用分光光度法测定了该菌株在不同浓度咔唑和联苯的矿物培养基中的生长速率以及对咔唑和联苯的降解性能。结果表明,在pH为7、8、9时,PJ3菌株的生长速率一致,而且高于其他pH值的生长速率。在pH为7、咔唑浓度为0.1mg.ml-1的CNFMM培养基中,PJ3菌株生长速度较快,而且15d咔唑的降解率可达到73%。在pH为7、联苯浓度为0.5mg.ml-1的MSB培养基中PJ3菌株生长最好。在0.1和0.5mg.ml-1联苯浓度下,15d对联苯的降解率可达80%～85%。综合评价,PJ3菌株降解咔唑比较适宜的浓度范围应该为0.1～0.2mg.ml-1,降解联苯较适宜的浓度范围为0.1～0.5mg.ml-1。     

聚磷茵JPA1菌株的生长特性和聚磷条件的优化

以YG培养基为基础,考察不同条件对聚磷菌JPA1菌株生长及聚磷效率的影响。结果表明：JPA1菌株生长的对数期为3-9h,9h后进入稳定期,12h到达衰亡期。在单因素试验中,麦芽糖为JPA1菌株最适生长和聚磷的C源,最适生长温度为30-35℃,pH为8,Na＋、Ca2＋、Mg2＋、Mn2＋和K＋等离子有利于JPA1菌株的生长;最适聚磷温度为30-35℃,pH为7,Fe2＋、Na2＋、Mg2＋、Mn“和K＋等离子有利于JPA1菌株的聚磷。正交试验结果表明：JPA1菌株去磷培养基的最优组合为麦芽糖1．5g／L,温度37℃,pH6．5,装液量50mL（300mL摇瓶）;菌株最适扩增培养基为麦芽糖1．5g/L,温度37℃,pH6．5或7．5,装液量150mL（300mL摇瓶）。     

对蜱致病性球孢白僵菌培养条件的优化

对前期筛选得到的具有生防潜力的杀蜱真菌Beauveria bassiana AT17菌株进行相关生物学性状的研究,建立一套规范的实验室培养的技术和方法,同时对其液固双相发酵技术进行优化,在于提供优质高效的生防材料,为其真菌制剂的规模化生产提供实践和理论基础。通过采用单因素筛选方案对其最适基础培养基、温度、pH值、碳源、氮源、微量元素及液固双相发酵配方进行研究,发现该菌株在PDA、PPDA、PDAY、SDAY、SMAY 5种培养基上均能较好生长,在PDA上生长最快,在PDAY上产孢量最大。温度对菌丝的生长和产孢影响显著,25°C菌丝生长最快,且产孢量最大。B.bassiana AT17菌株在pH 4-10范围内均可生长,在偏碱性环境内生长最快,在pH 5-6的偏酸性环境内产孢量最大。综合评价真菌各项指标后,葡萄糖和酵母粉为菌丝生长和产孢的最佳碳源和氮源,固体物料麦麸+玉米粉+米粉与基础培养液3/4 SDAY按2:1均匀混合后,添加0.05%K+可作为菌株固体发酵的最佳物料配方组合。     

药用野生稻拮抗稻瘟病内生细菌的筛选、鉴定及发酵条件优化

【背景】稻瘟病是水稻的三大重要病害之一,每年对水稻生产都会造成较大的损失,生物防治稻瘟病已成防治该病害的重要手段,而目前鲜少有报道从药用野生稻中分离内生菌用以防治稻瘟病。【目的】从药用野生稻内生菌中挖掘对稻瘟病具有拮抗作用的微生物资源。【方法】采用分离法从勐遮药用野生稻中先分离出内生菌,再通过平板对峙法筛选对稻瘟病菌具有拮抗作用的菌株,通过形态学和16S rRNA基因序列分析对菌株进行鉴定,同时筛选该菌株的最适培养基、pH、培养温度和摇床转速。【结果】筛选得到拮抗菌株Z5,在LB培养基上对稻瘟病菌菌丝生长的抑制率达到96.43%,经形态学和16S rRNA基因序列分析,初步鉴定为短小芽孢杆菌(Bacillus pumilus)。在NYBD、CM、LB、NA和YSP这5种培养基中,菌株Z5的最适培养基为NYBD培养基、最适pH值为8.0-9.0、最适培养温度为35℃、最适摇床转速为250 r/min。【结论】短小芽孢杆菌Z5对稻瘟病菌的生长具有较好的抑制作用,且该菌株耐高温、较耐酸碱,作为稻瘟病生防制剂研发具有一定的价值。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism