Screening and selecting novel AM fungi and Azotobacter strain for inoculating apple under soil solarization and chemical disinfestation with mulch practices for sustainable nursery management

The objective of this study is to investigate the response of screening, and selection of novel indigenous AM fungal species and Azotobacter chroococcum strains for inoculating apple under different soil disinfestations and moisture conservation mulch practices for sustainable nursery management. Two local AM fungal species namely, Glomus fasciculatum (Thaxter sensu Gerdemann) and Glomus mosseae (Nicol. & Gerd.), and two strains of A. chroococcum viz., A. chroococcum strain-I (AZ₁) and A. chroococcum strain-II (AZ₂) were inoculated at nursery stage under soil solarization, chemical disinfestation and natural soil conditions at four different mulch materials namely, black plastic mulch (BPM), and organic mulches, i.e. grass mulch (GM); cover crops (CC); green manuring + clean cultivation (Gm + Cc). The comparative performance of the seedlings on the impact of local AM species and A. chroococcum strains on growth characteristics, microbial population, root colonization and leaf nutrient status was evaluated. The inoculation of seedlings to G. fasciculatum and AZ₁ increased all growth characteristics (plant height, stem diameter, leaf area and total root length), microbial consortium of the rhizosphere soil and leaf N, P, K and Zn content in all those plots where soil solarization and black plastic mulching was used followed by chemical disinfestations and natural soil conditions at all other mulch types used. These findings suggested that the soil inoculation of G. fasciculatum and AZ₁ strain to seeds and/or the saplings under soil solarization with black plastic mulch attained a desirable plant height and become ready for grafting which however saved a period of 1 year for nursery management compared to traditional nursery raising practice, and thus, it may be a viable and feasible approach to maintain soil productivity under nutrient limited soils for sustainable apple nursery production under temperate rain-fed conditions.     

微波杀灭霉变玉米中寄生曲霉动力学模型

为描述微波对霉菌的杀菌过程和预测杀菌效果,建立了微波对霉变玉米中寄生曲霉孢子的杀菌动力学模型.在50～75C的微波加热条件下获得了寄生曲霉孢子的致死曲线.选取线性模型、Weibull模型和Weibull 简化模型来拟合微波杀菌的动力学过程,以决定系数、均方误差、精确因子和偏差因子作为模型拟合度优劣的评判指标.结果表明,Weibull模型较线性模型能更好地拟合微波处理下寄生曲霉孢子失活动力学变化;Weibull模型简化后与原模型具有相似的拟合性,可有效预测特定温度-时间组合下的微波灭菌效果;通过Weibull模型预测微波杀菌时间可避免线性模型导致的杀菌不彻底或者过度杀菌的现象.     

土壤高温处理对连作草莓根系呼吸代谢及植株发育的影响

为探讨草莓连作障碍机理,模拟太阳能消毒设置5个连作土壤高温灭菌处理,研究不同处理对草莓根系呼吸代谢及植株生长发育的影响。结果表明,连作土壤经高温灭菌后,各处理土壤中细菌和真菌数量都显著降低,经70℃高温连续20 d处理的土壤中真菌甚至消失,且对草莓根系呼吸代谢及植株发育的促进效果最明显;70℃高温连续10 d处理及55℃高温连续20 d处理对草莓植株生长、根系活力和根系总呼吸速率都具有不同程度促进作用,前者依然以PPP呼吸途径为主,后者的TCA呼吸途径是PPP呼吸途径的1.34倍;连作土壤55℃高温连续10 d处理作用效果最差。可见连作土壤高温灭菌后,土壤微生物数量减少,促进草莓根系呼吸代谢及植株生长,减轻了草莓的连作障碍,进而证明了土壤微生物是引起草莓连作障碍的重要因素之一。     

Promotion of the seed germination and seedling growth of cabbage by root-colonizing fungi isolated from oat and Eucalyptus roots

(Jpn. J. Soil Sci.Plant Nutr., 77, 257–263, 2006)
The symptom of blighted leaves was observed for the melon plants grown on an isolated soil bed after steam sterilization (SS) in a greenhouse in Kochi Prefecture, Japan. To clarify the causes of this symptom, soil and plant analyses were conducted in the first experiment. Manganese concentrations in the leaves with the symptom were higher than 1,000 mg kg−1and exchangeable Mn in the soil was higher than 30 mg kg−1, which indicated the observed symptom was due to Mn excess. In the second experiment, formation of Mn oxide-dissolving substances after SS was examined for several organic amendments, because large amounts of palm chips had been supplied to the soil before SS in the first experiment. As a treatment similar to SS, palm chips, bark compost, and cattle feces manure were autoclaved. The water extracts were collected before and after the autoclave treatment and the Mn oxide-dissolving capacities of the extracts were evaluated. The Mn oxide-dissolving capacity of the water extracts after SS was remarkably higher than before SS, and the value was highest in palm chips, and followed by bark compost, and cattle feces manure. Fractionation and HPLC analysis of the water extracts after SS revealed that the main substance behind Mn oxide reduction in palm tips was arabinose and that in bark manure was malic acid. Further, Mn oxide-dissolving capacities of the water extracts were almost completely explained by the amounts of arabinose or malic acid found in these materials. From these results, it was considered that reducing substances such as arabinose were released by SS from the palm chips which had been applied in large quantity before SS and these reducing substances dissolved the soil Mn oxides and increased the amounts of available Mn, which led to the occurrence of Mn toxicity to the plants.     

食品级过氧化氢对染菌虾仁杀菌效果研究

就新型杀菌技术-过氧化氢杀菌在虾仁加工过程中的应用进行了初步探讨。结果表明:过氧化氢对虾仁的适宜作用条件为:有效过氧化氢浓度1·27g·L-1,作用时间为2min,浸泡液与样品的比例为2:1或浸没样品。过氧化氢溶液受温度影响较大,溶液于低温下放置,随放置时间的延长,有效过氧化氢浓度逐渐降低,操作过程宜在低温条件下进行。过氧化氢溶液处理后的样品宜进行适度的水洗处理,以便去除大量残留在虾仁表面的过氧化氢,同时可以阻止残留过氧化氢对虾仁有机质成分的进一步氧化。     

邻苯二甲醛杀菌作用研究

为了检测邻苯二甲醛（ortho-phthalaloehyole,以下简称OPA）的杀菌效果。我们选择大肠杆菌，沙门氏菌，葡萄球菌，魏氏梭菌，荧光假单胞菌，蜡样芽孢杆菌作为试验菌株，采用MIC法测定OPA在不同温度下的最低杀菌浓度，并与甲醛，戊二醛作比较，同时将OPA配成5%的存贮液置不同条件下保存，测定其稳定性，试验结果表明，0.1%-0.7%（W/V）OPA具有杀菌作用，其5%的存贮液在不同条件下保存10个月以上，杀菌效果基本不变。     

水稻种子消毒剂三·福混剂的特性及药效试验

三·福混剂（901）是防治水稻恶苗病的种子消毒剂。产品剂型稳定，毒性低，田间示范防治效果高于生产上推广的其它药剂。成本低，使用方便。     

乳酸发酵大生产染茵分析及处理

简要介绍了乳酸大生产灭菌操作要点，从不同方面分析染菌的原因，并提出了预防和治理措施。     

高频感应重熔等离子喷涂NiWC25涂层性能的研究

人们对等离子喷涂工艺试验研究得比较充分,但对涂层性能尤其是经过重熔处理的涂层性能研究很少。本文概括地介绍了等离子喷涂重熔技术在拨丝机塔轮产品强化和旧件修复上的应用。并以此为基础,重点研究了重熔涂层的性能,如结合强度、摩擦学行为等,分析了涂层缺陷及产生的原因。从而为拨丝机塔轮的表面强化和修复提供了指导性资料。     

Comparison of measurements of canine plasma creatinine, glucose, proteins, urea, alanine aminotransferase, and alkaline phosphatase obtained with Spotchem SP 4430 and Vitros 250 analyzers

The suitability of the Spotchem 4430 benchtop biochemistry analyzer for canine blood samples was tested for creatinine, glucose, proteins, urea, alkaline phosphatases and alanine aminotransferase. Results obtained from whole blood and corresponding heparin plasma were identical except for proteins which were higher in plasma (n=10). Between series imprecision (n=10) was <5% for substrates and <10% for enzymes. Comparison of results from 100 Li-heparin samples with those measured with a Vitros 250 analyzer showed good correlation (r>0.93). The slopes of the Passing-Bablock's regression ranged from 0.90 to 1.20 and intercepts were low. The mean biases were low, except for creatinine for which the results obtained by Spotchem (Jaffe reaction) were about 20 micromol/L higher than with the Vitros (enzymatic reaction). The results of this study show that the Spotchem analyzer is suitable for use in canine whole blood or plasma when small numbers of tests are to be performed and large analyzers are not available.