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Lebeda A., Kroftova V., Kůdela V., Braunova M. (2014): Fifty-year anniversary of Plant Protection Science. Plant Protect. Sci., 50: 53–63 In 2014, the journal Plant Protection Science (PPS) completes 50 years of publication (1965–2014). However, its roots extend back to the year 1921. Today, it is an international scientific journal focused on all aspects of plant protection sciences, fully published in English. This occasion offers a fitting opportunity to describe some of the most important historical stages of the journal’s development. In our brief historical overview, we summarise the changes in journal title, chief-editors, and editorial policy during the last fifty years, and with an examination of its importance, scope and readership. We present analyses of the journal’s development, some for the entire period of 1965–2013, while others are limited to more recent decades. The journal’s present place among the world’s scientific journals is documented by analyses in the international citation databases, BIOSIS CI, SCOPUS, and WOS. An analysis of three particular citation databases were made in October 2013, while the overall period 1998–2013 was conducted from All Databases/ Thomson Reuters in March 2014. PPS is also included in other, important technical-literature databases, including Czech Agricultural and Food Bibliography, AGRIS/FAO database, AGRICOLA, CAB Abstracts, Current

Kůdela V. (2011): On the need for revision of some names of plant health malfunctions and their categorisation. Plant Protect. Sci., 47: 133–148. The development of branches dealing with plant health science and plant health care proceeded more or less in three separate disciplines dealing with microbial plant pathogens (plant pathology), animal pests (applied entomology, etc.) and weeds (weed science). It resulted in disunity in concepts of basic terms such as disease, disorder and injury, in different approaches to categorisation and naming of the main types of plant health problems, and in ambivalence in the use of names for plant malfunctions of abiotic origin. Different terms are used with varying frequency for denoting the same phenomenon. The tenor of this article is to submit some suggestions for redefinition of the main types of plant health problems, their new classification and categorisation. We used the following criteria for classification of a wide spectrum of plant health problems: origin of causal agent, the mechanism by which the causal agent disrupts plant health, and epidemiological features. After the analysis of common and different properties of particular plant health problems and relationships between them, we categorised them using three neologisms, namely bioticosis, abioticosis and co-abio-bioticosis. Redefinitions of the main types of plant health problems are presented. A polyfunctional role of animal pests in plant malfunctions is discussed. Besides, examples of proposed common names for plant malfunctions caused by abiotic agents are given. The objective of the submitted suggestions is to support efforts aimed at conceptual, nomenclatural and institutional unification of plant medicine as a theoretical/practical branch.

KŮDELA V., VOŽENILKOV A B., KREJZAROV A R., KREJZAR V., JANOUCH M. (2005): Destruction of chlorophyll in emerging seedlings of spring barley associated with environmental stresses. Plant Protect. Sci., 41: 165–170. An unusual disorder occurred on spring barley seedlings in southern and central Bohemia in April 2005. Affected seedlings showed conspicuous bleached or straw-coloured areas on tips of the first leaves. There were very sharp, distinct, horizontal boundaries between the green basal and discolored tip parts of the leaves. It was remarkable that these boundaries were at the same position on all affected first leaves of seedlings from the same field. Affected seedlings were randomly distributed in the fields, and their incidence ranged from about 20 to 70% according to location. Based on meteorological data it can be concluded that the colour abnormality in emerging seedlings was associated with specific environmental stresses, being effective in certain chronological order on sensitive plant tissues during the period from 6 to 8 days after seeding. These stresses include frosty mornings followed by clear days with high solar radiation with a high UV Index.

Under controlled inoculation, a set of 49 accessions belonging to 16 wild species and varieties of the genus Cucumis was tested for resistance to Pseudomonas syringae pv. lachrymans. There was no complete resistance to this pathogen in Cucumis accessions, but limited necrotization of leaves was observed in four accessions (C. africanus (PI 203974), C. anguria var. longipes (CUC 28/1974), C. melo subsp. conomon Baj-Gua (CUM 238/1974), C. zeyheri (PI 299572)). There were some quantitative differences between Cucumis accessions in disease symptom development.

The effect of structure of membranes on the desalination process of milk whey by electrodialysis and their changes in long-term desalination have been investigated. Electrochemical and physicochemical properties of each membrane in the stack were examined at the moment of a steep drop in the efficiency of the process. The effect of sorption of milk whey components in the membranes on the change in their transport properties is demonstrated. Asymmetry in the sorption of ionic milk whey components in the membrane stack has been ascertained and proved to be related with the electric resistance and permselectivity of the membranes.

Fifty Erwinia herbicola isolates obtained from host plants were examined in an agglutination reaction with antiserum prepared against E. ananas (E. herbicola) strain CCM 2407 antigen of plant origin and with antiserum prepared against Enterobacter agglomerans strain CNCTC M 269 antigen of human origin. In tests with strain CCM 2407 antiserum, 56% isolates showed a positive reaction, while in tests with strain CNCTC M 269 antiserum only 14% isolates showed a positive reaction. Among E. herbicola isolates which showed a positive reaction with CCM 2407 antiserum 18% showed a positive reaction with the CNCTC M 269 antiserum too. Our results confirmed the serological heterogeneity of E. herbicola population. In spite of the difference in the origin of the two antigens used for the preparation of antisera (plant, human; Japan, Czech Republic) our results indicate that some of our E. herbicola strains and E. agglomerans strain CNCTC M 269 are serologically identical.

Summary Of 45 Fusarium strains, isolated from cortical discoloration of the tap and secondary roots and from vascular core of red clover, preliminary tested for pathogenicity on red clover and alfalfa, only 15 isolates, belonging to the five species: F. solani, F. avenaceum, F. oxysporum, F. oxysporum var. orthoceras, and F. sambucinum, has the capability of inciting symptoms of disease. They were tested for pathogenicity on 9 forage legumes in vitro. It was established that in each tested plant species F. solani inhibited root and top growth. F. avenaceum induced rot of roots in all forage legumes, except in white clover and big trefoil. F. oxysporum and F. oxysporum var. orthoceras caused chlorosis of leaves in all host-plants, except in white clover and birdsfoot trefoil. Damages caused by F. sambucinum in red clover, alsike clover, crimson clover, birdsfoot trefoil, and kidney vetch were negligible; it had weak pathogenicity to white clover and no pathogenicity to alfalfa. Disease development was mainly dependend on the time since the infection proceeded. There was significant reduction in the weight of plants, characteristic of infection with F. solani. Contrary to that, an increase of weight was observed in case of infection by F. oxysporum, F. oxysporum var. orthoceras, and partly even by F. sambucinum on the 16th day after inoculation.

Gels cross-linked to various degrees and containing various amounts of nitrile, amide and carboxylic groups were prepared by polymerizing acrylonitrile at various concentrations in aqueous 70 per cent ZnCl2 solution and by hydrolysis of polymers for various times in HCl vapours. Chemical characteristics of gels, concentration membrane potentials, membrane functions and permselectivities in KCl solutions were determined. It was proved that under the conditions used (pH close to 7, content of acrylic acid in the copolymer only 1·4–3·9 mole %). cross-linking is the decisive factor for permselectivity and ideality of the membrane functions. Cross-linking yielded almost 100 per cent permselectivity values and a slope of the membrane function of about 55 mV/decade. Further hydrolysis impairs the ideality of membranes, since the increase in swelling outweighs the effect of the increase in concentration of the active groups. Variability of the density of the ionizable groups is not sufficient to explain differences in the behaviour of the membranes under investigation.

Big vein disease occurring on lettuce plants cv. ‘Pražan’ was identified and the susceptibility to this disease was tested on 9 lettuce cultivars of foreign origin. Lettuce big vein virus was confirmed to be the cause of the disease. The transmission of the LBVV by the fungusOlpidium brassicae (Wor.)Dang., the sporangia of which were found by microscopy in the cells of surface tissues of lettuce roots, was experimentally proved. Rod-like particles, the average length of which was estimated at 244 nm, were found in the roots of diseased plants. LBW transmission by mechanical inoculation and by aphids could not be proved.

Summary Equimolar solution of urea and ammonium nitrate shows synergistic bactericidal activity against Agrobacterium tumefaciens, Xanthomonas campestris pv. vesicatoria and Pseudomonas aeruginosa in comparison with the activity of urea or ammonium nitrate alone. There is no synergism against Erwinia chrysanthemi pv. chrysanthemi and Corynebacterium michiganense pv. insidiosum , which were also highly sensitive to the single compounds. The NPMg liquid fertilizer was toxic to all the species tested, but less than urea + ammonium nitrate equimolar solution. SKsol and NPsol exerted low toxicity to E. chrysanthemi pv. chrysanthemi and C. michiganense pv. insidiosum and no toxicity to the other species tested. Equimolar solution of urea + ammonium nitrate proved to possess bactericidal activity at a concentration substantially lower than these used for foliar application.

The Hyp content was studied in cell wall of alfalfa susceptible and resistant strains on the 3rd, the 7th and on the 14th day after inoculation with Verticillium albo-atrum or Corynebacterium michiganense pv. insidiosum. The changes of Hyp content after inoculation with both pathogens were markedly expressed in alfalfa roots. Resistant plants of R 337 strain responded to inoculation with V. albo-atrum or C. michiganense pv. insidiosum by the decrease of Hyp content mainly on the 3rd and on the 7th day. On the 14th day after inoculation Hyp content practically did not differ from that of the control. Susceptible plants of S 354 and S 321 srains responded to inoculation with wilt pathogens by the slight decrease of Hyp content at the 3rd day after inoculation. A significant increase of Hyp content was found on the 7th and mainly on the 14th day after inoculation in comparison with control plants. The cell wall Hyp content was also determined with 7 R-strains and 7 S-strains at 120 days after inoculation with both pathogens. In each R and S strain two categories of plants were used for chemical analyses: Wilt-free plants (0 to 1 classes) and diseased, wilted plants (2 to 6 classes). In the resistant alfalfa strains no differences in Hyp content between the wilt-free and diseased plants were found. In the susceptible alfalfa strains the Hyp content was significantly higher in roots of diseased plants comparing with the wilt-free ones. Only negligible changes in Hyp content were registered in the overground parts of all inoculated alfalfa strains.

The paper deals with studies of electrochemical properties of membranes from a copolymer of 2-hydroxyethyl methacrylate with ethylene dimethacrylate, modified by introducing weak acidic and/or weak basic groups. The acidic, basic and ampholytic membranes have been characterized by values of concentration potentials of KCl solution pairs with the concentration ratio 1:2, permselectivity and the course of membrane functions. Effects of the ionogenic group concentration, network density of the membranes and the hydrophilicity of the ionogenic group upon the electrochemical properties of membranes are discussed. Existence of a significant effect of the free diffusion on the value of concentration potentials is deduced especially from differences in slopes of the membrane functions.

Summary Lucerne (Medicago sativa L.) seedlings of relatively resistant cultivar Hodoninska (R-cultivar) and those of very susceptible cultivar Přerovska (S-cultivar) were inoculated at the stage of cotyledons with Cornynebacterium insidiosum (McCulloch) Jensen. The plants were analysed on the 20th, 35th, and 50th day after inoculation. After the acid hydrolysis with 6 N HCl, the content of bound amino acids was determined using an automatic analyser. The total amino acid content, especially of proline, glycine, alanine, phenylalanine, and isoleucine, and in the case of the R-cultivar also the histidine content was increased, due to the infection. The increase in total amino acid content, due to the infection and the change in the content of individual amino acids, were in R-cultivar most pronounced on the 20th day and in S-cultivar plants on the 35th day after inoculatin. The amino acid content of inoculated plants dropped to the level of control plants on the 50th day after inoculation.

Ampholytic membranes were synthesized by copolymerizing (2-hydroxyethyl)methacrylate as the hydrophilic component, methacrylic acid and (N,N-diethylaminoethyl)methacrylate as ionogenic components (both ionogenic monomers in amounts 2.5 mol% or 10 mol%), and ethylenedimethacrylate as the crosslinking agent (3,5 or 10 mol%). The effects of pH on the swelling and membrane potentials of the membranes were investigated. The dependence of the membrane potentials on pH is characterized by the position of the isoelectric point and by the slope of the straight part of the dependence. This slope reflects the attained degree of ideality of the membrane. By varying the degree of cross linking and the content of ionogenic components, it is possible to vary the pH-dependent response of the membranes.