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This moment in climate history can be deeply discouraging. The Trump administration's attacks on environmental protections and the Paris Agreement undermine earlier progress. As the United States waffles, time flies and holding global warming below 2°C requires ever deeper commitments and ever bolder actions. We also see 2020 as a rare moment of opportunity because the nation's obligations under the UN Framework Convention on Climate Change will remain in effect. One of these obligations is to create a national strategy called Action for Climate Empowerment (ACE). As leaders from diverse ACE communities and perspectives, we have organized an initiative to produce a collaborative ACE national strategic planning framework before the end of this year. This framework will achieve substantial progress in strategic planning and provide a roadmap for completing a U.S. ACE National Strategic Plan in time for COP26 in November of 2021.

The scientific community has made the urgent need to mitigate climate change clear and, with the ratification of the Paris Agreement under the United Nations Framework Convention on Climate Change, the international community has formally accepted ambitious mitigation goals. However, a wide gap remains between the aspirational emissions reduction goals of the Paris Agreement and the real-world pledges and actions of nations that are party to it. Closing that emissions gap can only be achieved if a similarly wide gap between scientific and societal understanding of climate change is also closed. Several fundamental aspects of climate change make clear both the need for education and the opportunity it offers. First, addressing climate change will require action at all levels of society, including individuals, organizations, businesses, local, state, and national governments, and international bodies. It cannot be addressed by a few individuals with privileged access to information, but rather requires transfer of knowledge, both intellectually and affectively, to decision-makers and their constituents at all levels. Second, education is needed because, in the case of climate change, learning from experience is learning too late. The delay between decisions that cause climate change and their full societal impact can range from decades to millennia. As a result, learning from education, rather than experience, is necessary to avoid those impacts. Climate change and sustainability represent complex, dynamic systems that demand a systems thinking approach. Systems thinking takes a holistic, long-term perspective that focuses on relationships between interacting parts, and how those relationships generate behavior over time. System dynamics includes formal mapping and modeling of systems, to improve understanding of the behavior of complex systems as well as how they respond to human or other interventions. Systems approaches are increasingly seen as critical to climate change education, as the human and natural systems involved in climate change epitomize a complex, dynamic problem that crosses disciplines and societal sectors. A systems thinking approach can also be used to examine the potential for education to serve as a vehicle for societal change. In particular, education can enable society to benefit from climate change science by transferring scientific knowledge across societal sectors. Education plays a central role in several processes that can accelerate social change and climate change mitigation. Effective climate change education increases the number of informed and engaged citizens, building social will or pressure to shape policy, and building a workforce for a low-carbon economy. Indeed, several climate change education efforts to date have delivered gains in climate and energy knowledge, affect, and/or motivation. However, society still faces challenges in coordinating initiatives across audiences, managing and leveraging resources, and making effective investments at a scale that is commensurate with the climate change challenge. Education is needed to promote informed decision-making at all levels of society.

In recent years, various climate change education efforts have been launched, including federally (National Oceanic and Atmospheric Administration, National Aeronautics and Space Administration, National Science Foundation, etc.) and privately funded projects. In addition, climate literacy and energy literacy frameworks have been developed and deployed, and both have been reviewed and endorsed by the U.S. Global Change Research Program. This paper describes a community-based effort to promote climate and energy literacy: the CLEAN Network (originally the Climate Literacy Network). We describe results from a member survey about the importance of the network to the members' professional lives and review the development and position of the network within the larger community of climate and energy literacy stakeholders. The CLEAN Network was first formed in 2008 to support climate literacy efforts, largely through voluntary efforts. It serves as a champion and rudimentary and unfunded backbone suppor...

Educators seek to develop 21st century skills in the classroom by incorporating educational materials other than textbooks into their lessons, such as digitally available activities, videos, and vi...

Determining virulence towards race-specific resistance genes is a prerequisite to understanding the response of pathogen populations to resistant cultivars, and therefore to assess the durability of these resistance genes and the performance of resistance management strategies. In Phytophthora infestans, virulence testing began shortly after the introduction of R-genes from Solanum demissum into S. tuberosum cultivars. However, the characteristics of R-gene expression, the sensitivity of the phenotype to environmental and physiological parameters, and the diversity of experimental protocols make the comparison of data from different studies problematic. This prompted European teams working on P. infestans diversity to: (i) design a joint protocol, using detached leaflets from greenhouse-grown plants of a shared set of differential cultivars inoculated with standardized suspensions of inoculum, and (ii) assess the performance of this protocol in a blind ring test involving 12 laboratories and 10 European isolates of the pathogen. A high level of consensus in the determination of virulence/avirulence to R1, R3, R4, R7, R8, R10 and R11 was achieved among the collaborators, showing that the protocol could be robustly applied across a range of laboratories. However, virulence to R2, R5 or R9 was detected more frequently in some laboratories, essentially from northern Europe; these genes are known to be highly sensitive to host and environmental conditions. The consensus determination was often markedly different from the original virulence phenotype of the isolates, suggesting virulence instability in stored P. infestans isolates. This indicates that creating reliable core collections of pathogen isolates with known virulences could be difficult.

The advent of the Internet and evolutionary advances in geospatial data browsers, virtual globes, and immersive visualization displays have significantly increased the potential for a more climate science literate public. At the same time, space-based Earth-observing agencies like NASA and NOAA in the United States have geometrically increased the volume of data they collect everyday over the entire globe. Fortunately, Moore's Law held true during that same time span, so that the processing capacity of modern computers has exponentially increased, enabling scientists to collect, process, and share these data with increasing efficiency and turnaround time. Since 1980, the combination of these technologies has substantially increased public access to cutting-edge climate science data and information. But has there been a corresponding increase in public climate science literacy? Has there also been a corresponding improvement in public attitudes and opinions about climate science research? In this paper, we...

Two diagnostic methods have been applied for detecting the plant pathogenic fungus Ganoderma, a basidiomycete, causing the basal stem rot (BSR) disease of oil palms. One approach was the use of polyclonal antibodies (PAbs) raised against mycelial proteins of a single Ganoderma isolate and a mixture of nine different Ganoderma isolates. Both PAbs could detect Ganoderma in diseased oil palm root tissue by applying an indirect enzyme-linked immunosorbent assay. Low cross-reactions were observed with the five mainly occurring saprophytic fungi which could be isolated from diseased oil palms and were used as negative controls. The other approach was based on the polymerase chain reaction (PCR) in order to increase the sensitivity of the Ganoderma detection. The primers were generated from the internal transcribed spacer region 1 of rDNA of Ganoderma boninense and produced an PCR product of 167 bp in size. Fungal isolates and oil palm root samples were processed for PCR by three different DNA extraction methods. The most suitable extraction procedure was a simple alkaline extraction method. For a practical approach, a semiquantification was performed by assessing the PCR sensitivity limits of pure culture Ganoderma and naturally infected root samples.

The effect of the two newly developed peracids (the percarbonic acid Clarmarin and the peracetic acid Degaclean) from the Degussa company was tested using the two quarantine bacteria Ralstonia solanacearum and Clavibacter michiganensis ssp. sepedonicus. To obtain results for practical use, the sewage water of a starch company in Germany which contained soil and potato tuber debris was used. This population of micro-organisms that naturally occur in the sewage water was chosen as the standard to evaluate the conventional bactericidal compounds in comparison to the peracids. It could be shown that the catalases of the micro-organisms caused tremendous activity losses of the peracids. To inactivate these proteins, the application of a catalase inhibitor (KH10) was necessary, since the use of peracids alone required 20000ppm and a standard incubation time of 20 min. With the combination of Clarmarin/KH10 (1 : 1) in a concentration of 2000 ppm and the standard incubation time the indigenous microbial population could be destroyed, whereas all other tested compounds, including the conventional hydrogen peroxide perhydrol' had only a small influence on the eradication rate. In laboratory-scale experiments only 100-200 ppm of the Clarmarin/KH10 mixture and an incubation time of 1-2 min was required to absolutely destroy a cell suspension of 10 9 cells/ml of the two quarantine bacteria, suspended in an aqueous solution (Ringer). This result shows that the possibility now exists to efficiently interrupt the infection cycle of quarantine bacteria if, for example, contaminated surface water is used for irrigating potato fields. In addition to the very fast reaction with organic compounds of the Clarmarin/KH10 mixture, there is a good environmental tolerability, since both peracids disintegrate into water, gaseous oxygen and easily degradable organic compounds.When adding the quarantine bacterium Ralstonia solanacearum as a rifampicin-resistant isolate at a concentration of 10 9 cells/ml into the sewage water of the German starch company, the bacterium could be destroyed by applying a concentration of 1000 ppm of the Clarmarin/KH10 mixture for 20min. By applying this small amount of the Clarmarin/KH10 mixture to the sewage water it has the advantage that not all indigenous micro-organisms are destroyed, since they might be needed in the subsequent decomposition process of the sewage water.

A modified NaOH alkaline boiling procedure using a mixture of lysozyme and proteases combined with minimized TRIS/HCl/BSA buffer volume was applied to extract amplifyable DNA from the two quarantine bacteria Ralstonia (Pseudomonas) solanacearum and Clavibacter michiganensis ssp. sepedonicus artificially added to potato tuber extracts of a low and a high starch potato variety. A PCR detection threshold of 104−105 colony forming units per ml extract of each quarantine bacterium was obtained by using the two potato varieties, the high starch potato variety resulting in a lower detection threshold. Similar sensitivities could be obtained from potato tubers naturally infected with both quarantine bacteria. When comparing a published DNA extraction procedure suitable for Clavibacter michiganensis ssp. sepedonicus with the alkaline extraction the latter is much faster and simpler with similar detection thresholds and representing an inexpensive method to obtain suitable template DNA for routine PCR tests. Zusammenfassung Eine einfache und schnelle Extraktionsmethode zur Gewinnung von amplifizierbarer DNA aus mit Ralstonia (Pseudomonas) solanacearum und Clavibacter michiganensis ssp. sepedonicus inokulierten Kartoffelknollenextrakten und naturlich infizierten Kartoffelknollen zur Durchfuhrung einer Polymerase-Ketten-Reaktion (PCR) Eine modifizierte alkalische NaOH-Kochmethode, kombiniert mit einer Enzymmischung aus Lysozym und Proteasen sowie einem minimierten TRIS-HCl-BSA-Puffer -Volumen, wurde verwendet, um amplifizierbare DNA von den beiden Quarantanebakterien Ralstonia (Pseudomonas) solanacearum und Clavibacter michiganensis ssp. sepedonicus zu gewinnen. Die Bakterien wurden zuvor kunstlich Kartoffelknollenextrakten einer Speise-und Starkesorte hinzugegeben. Dabei konnte eine PCR-Nachweisgrenze von 104 bis 105 Kolonien bildenden Einheiten von beiden Quarantanebakterien erhalten werden, wobei aber die DNA-Extraktionen aus der Starkekartoffel stets eine niedrigere Nachweisempfindlichkeit aufwiesen. Ahnlich gute Sensitivitaten konnten auch von naturlich mit den beiden Quarantanebakterien infizierten Kartoffelknollen erhalten werden. Im Vergleich zu einer anderen fur Clavibacter michiganensis ssp. sepedonicus veroffentlichten DNA-Extraktionsmethode ist die alkalische Extraktionsmethode bei vergleichbarer Nachweissensitivitat wesentlich schneller und einfacher zu handhaben, und reprasentiert zudem eine preiswerte Methode, um amplifizierbare DNA fur PCR-Routinetests zu extrahieren.

Contamination of seed potato tubers by Erwinia carotovora subsp. atroseptica is widespread with the bacteria usually sited superficially in lenticels and suberized wounds. As seed contamination level is related to blackleg incidence, seed health is best assessed by determining the number of cells of E. c. atroseptica per mL of tuber-peel extract. The relative specificity, sensitivity and ease of use of four recently developed microbiological, immunological and molecular methods to detect and/or quantify tuber contamination are discussed in relation to the testing of commercial seed stock. Sensitivities of all four methods are at or below the threshold level for blackleg development (< 103 cells mL-1), but there are differences regarding their specificity and ease of use. Three of them allow enumeration of most live cells of the bacterium, using specific monoclonal and polyclonal antibodies against the predominant serogroup I: (a) immunomagnetic separation of E. c. atroseptica before viable count on a selective-diagnostic growth medium, crystal violet pectate, (b) immunofluorescence staining and counting of colonies in pour-plate medium in tissue culture plates and (c) enrichment of the bacterium in peel-extract dilutions directly in microtitre plates prior to DAS-ELISA. In the fourth method, both live and dead cells are detected, but not quantified, by PCR amplification of target sequences using specific primers for E. c. atroseptica regardless of serogroup.

A characterized and sequenced repetitive satellite DNA fragment from Phytophthora infestans ( P. infestans ) was used to synthesize primers for performing a one-tube PCR (nested or multiplex PCR) generating a 276 bp DNA fragment. The specificity of the primers was established by means of target DNA from all known A1 mating type P. infestans races 1, 3, 4, and 1–11, occurring in Germany, and selected A2 mating types. No amplificate was obtained when testing a collection of potato pathogenic fungi and bacteria. After optimization, a detection threshold corresponding to 10ng of freeze-dried mycelia per ml of P. infestans was found, giving the last visible PCR signal on an agarose gel dyed with ethidiumbromide. For further reducing the time needed to obtain amplifyable DNA from infected potato tubers, the infected potato tuber tissue was either boiled in Tween 20 solution by adding bovine serum albumin (BSA) or a NaOH and TRIS extraction procedure was used to routinely identify P. infestans mycelium. Since the one-tube PCR acquired a high sensitivity threshold, the application of the Tween 20 or NaOH and TRIS extraction for infected potato tuber material which is lower in yield but faster allows the detection of P. infestans in the plant tissue at an early stage of infection.

Monospecific antibodies were successfully obtained by using unique protein bands of the quarantine bacterium Xylella fastidiosa , the causal agent of Pierce's disease of grapevine, and by applying gel electrophoresis and electroblotting. The monospecific antibodies directed against the two best suited protein bands (20.7 kD, 19.8 kD) did not show any cross-reaction on a Western blot, a solid phase ELISA (Enzyme-Linked Immunosorbent Assay) or an IFAS (Indirect Fluorescent Antibody Staining). A monospecific antiserum was generated in rabbits directed against the 20.7 kD and 19.8 kD protein bands, and was applied in an ELISA. Formerly cross-reacting bacteria isolated from grapevine cuttings did not show any antibody reaction with this antiserum. When grapevine cuttings were pre-infiltrated with a suspension of 4.15 × 10 7 bacteria the detection limit was found to be 10 6 −10 5 cells in the sap extract using ELISA. Titer used in all assays of the monospecific antiserum was 1:100. Using pure cultures of Xylella fastidiosa the detection limit of the monospecific antiserum in an indirect ELISA was 8.30 × 10 5 cells/ml.

P. syringae pv. syringae strain R32 causes the bacterial brown spot disease on bush beans. A 31 kD protein was detected which is involved in the pathogenic response. Monospecific antibodies directed against this 31 kD-protein were used to screen a protein expression gene bank made from the wild type strain R32. A 0.8 kb DNA insert of a clone which gave a positive reaction with the monospecific antibodies was used in hybrizations to clone a larger chromosomal fragment. A km-cassette (kmresistance) was integrated into this chromosomal DNA-fragment preventing the expression of the 31 kD-protein. This construct was integrated into the chromosomal of the wild type strain R32 viahomologous recombination resulting in the 31 kD-protein deficient mutant LMI. Biotests with the host plant (bean) and with tobacco leaves showed no symptoms or hypersensitive reaction (HR) when the mutant LMI was inoculated. However, atypical chlorotic and necrotic lesions compared to the wild type strain R32 were found on tobacco leaves when the mutant LMI was incubated for more than 2 weeks. Complementation of the LMI mutant with a plasmid harbouring the corresponding wild type R32 DNA fragment resulted in an isolate (LMIC) which showed a partial restoration of the HR on tobacco but no brown spot disease symptoms on bush beans. The 31 kD-protein could be detected serologically in LMIC. Zusammenfassung Teilcharakterisierung eines an der pathogenese beteiligten 31 kD Protein-Gens von Pseudomonas syringae pv. syringae Bei P. syringae pv. syringae Isolat R32, dem Erreger der bakteriellen Braunfleckenkrankheit an Buschbohnen, wurde serologisch ein 31 kD-Protein nachgewiesen, das bei der Pathogenese involviert ist. Eine Protein-Expressions-Klonbank vom Wildtyp Isolat R32 wurde mit monospezifischen Antikorpern getestet, die mit dem 31 kD-Protein reagierten. Es wurde ein positiv reagierender Klon gefunden. Dessen 0,8 kb-Insert wurde zur Hybridisierung mit einer chromosomalen DNA-Klonbank vom Wildtyp Isolat R32 verwendet, um einen groseren Genbereich zu klonieren. In den fur das 31 kD-Protein codierenden Bereich wurde eine Kanamycin-Kassette (Km-Resistenz) integriert. Durch homologe Rekombination dieses Konstrukts in das Chromosom des Wildtyps Isolat R32 wurde die Expression des 31 kD-Proteins verhindert. Bei dieser Mutante (LMI) war es serologisch nicht mehr auffindbar. Biotests mit der Mutante LMI an der Wirtspflanze (Bohne) und an Tabak zeigten keine Symptome bzw. Hypersensitivitatsreaktion (HR). Atypische Chlorosen und spater auch Nekrosen zeigten sich jedoch an Tabakblattern, wenn die Mutante LMI zwei Wochen oder langer inkubiert wurde. Eine Komplementierung der LMI-Mutante mittels Plasmid resultierte in einem Isolat (LMIC), das im Biotest nur eine partielle Wiederherstellung der HR am Tabak bewirkte, aber keine Symptome an Buschbohnen zeigte. Das 31 KD-Protein war bei der Mutante LMIC serologisch wieder nachweisbar.

Climate and energy sciences are rapidly evolving with respect to both knowledge and available technology. At the same time, citizens of all ages need accurate, up-to-date information, knowledge of the sciences, and analytical skills to make responsible decisions and long-term plans regarding these challenging topics.

We describe a simple method of purifying Pseudomonas syringae pv. syringae (P. s. pv. s.) specific polyclonal antibodies which are directed against a cell surface protein sized 31 kD. The actual purification step of the polyclonal antibodies occurs with denatured proteins after an SDS-PAGE gel electrophoresis and western blotting. Polyclonal antibodies were obtained which recognized a 31 kD protein. On a western blot no cross reaction of the purified polyclonal ‘monospecific 31 kD antibodies’ with other proteins from the same strain was observed. However, a positive “monospecific 31 kD antibody” reaction was only visible when either protein extracts from several selected pathogenic P. s. pv. s. strains from different hosts, or two isolates of Pseudomonas syringae pv. pisi (P. s. pv. p.) were used. An indication that this 31 kD protein is specific to P. s. pv. s. is that no cross reaction was found with protein extracts from the tested pathogenic and non-pathogenic pseudomonads. However, a differentiation of the tested P. s. pv. s. and P. s. pv. p. isolates was possible when cells were grown above 30 °C. Then protein extracts from P. s. pv. s. revealed the lack of the 31 kD protein but not P. s. pv. p. protein extracts. Polyclonal antibodies raised in rabbits against the 31 kD protein band from the western blot proved to be specific enough to agglutinate whole P. s. pv. s. strain R32 cells or for detecting a single 31 kD protein band on a western blot when whole cell protein extracts of P. s. pv. s. strain R32 were used.

From comparison of the alignments of the internally transcribed spacers (ITS) of ribosomal DNA from Ganoderma associated with oil palm basal stem rot (BSR) and other Ganoderma species, two specific primer pairs were selected to provide a specific DNA amplification of pathogenic Ganoderma in oil palm. Each primer pair produced a single PCR product of about 450 bp (for primer pair IT1–IT2) and 334 bp (for primer pair IT1–IT3) when oil palm Ganoderma DNA was used. No PCR amplification product was observed when other Ganoderma species DNA was used in PCR amplification with these primer pairs. Three specific restriction enzyme sites were identified in the ITS and intergenic spacer (IGS1) regions. The restriction enzymes MluI, SacI and HinfI were used to digest the ITS-PCR product and restriction enzymes TfiI, ScaI and HincII were used to digest the IGS1-PCR product. Of the three restriction enzymes used in each rDNA region, MluI specifically digested the ITS regions, and TfiI specifically digested the IGS1 region of oil palm Ganoderma. Analysis of the published ITS nucleotide sequences of 31 Ganoderma species showed that the MluI restriction site was not present in other Ganoderma species. The use of both specific primers and restriction enzyme analysis can be applied as a standard protocol to identify pathogenic Ganoderma in oil palm. In this study, the use of specific primers and PCR-RFLP analyses of the rDNA gave consistent results for the characterisation of pathogenic Ganoderma, and indicated that Ganoderma strains associated with BSR disease in oil palms belong to a single species.

A number of phenotypic and molecular fingerprinting techniques, including physiological profiling (Biolog), restriction fragment length polymorphism (RFLP), enterobacterial repetitive intergenic consensus (ERIC) and a phage typing system, were evaluated for their ability to differentiate between 60 strains of Erwinia carotovora ssp. atroseptica (Eca) from eight west European countries. These techniques were compared with other fingerprinting techniques, random amplified polymorphic DNA (RAPD) and Ouchterlony double diffusion (ODD), previously used to type this pathogen. Where possible, data were represented as dendrograms and groups/subgroups of strains identified. Simpson's index of diversity (Simpson's D) was used to compare groupings obtained with the different techniques which, with the exception of Biolog, gave values of 0.46 (RFLP), 0.39 (ERIC), 0.83 (phage typng), 0.82 (RAPD) and 0.26 (ODD). Of the techniques tested, phage typing showed the highest level of diversity within Eca, and this technique will now form the basis of studies into the epidemiology of blackleg disease.

A characterized repetitive sequence from Phytophthora infestans (P. infestans) was used to perform a PCR with the DNA from the four races 1, 3, 4, and 1-11. To obtain amplifiable DNA, all extractions had to be purified by DNA adsorbing spin columns. Only two out of four tested primers were well suited and gave an DNA amplificate of the same size for all four races. After optimization the detection limit of the PCR corresponded to 100 ng of freeze-dried mycelia per ml, specificity was established when testing a collection of the most important potato pathogenic fungi and bacteria. Using P. infestans zoospores to infect tuber slices, the detection threshold was determined to be two days post infection when 3 to 6 zoospores were applied. After infiltrating the tenfold concentration into potato leaves a visible PCR signal was obtained one day post infection. Further improvements of the sensitivity threshold in detecting P. infestans for breeding and prognosis purposes are discussed.

For an industrial large-scale production of alpha amylase with an rDNA B. subtilis a case study was performed in the former G.D.R. from 1986–1990. Unintended releases of production strains are expected to occur in most cases of large-scale fermentations under safety level 1 conditions. Dominant release routes are via air (exhaust air from aerobic fermentation), biomass (after separation of the production strain from the extracellular enzymes) and waste water (Smalla et al. 1991). Our investigations were focussed on monitoring the extent and routes of release, characterization of microbial composition of bioprocessing waste, the fate of rDNA B. subtilis in sterile and nonsterile environmental media (potential recipient habitats such as soil, river water or waste water) and transfer of rDNA to indigenous microbes.

Proteins from the blood disease bacterium (BDB) affecting banana and plantain and proteins from other bacterial species were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, blotted onto nitrocellulose membrane, and probed with polyclonal antibodies directed against BDB. A 33.5-kDa protein band was characteristic for all virulent strains of BDB examined. Monospecific antibodies obtained against this protein by affinity purification were specific for BDB. A second polyclonal antibody was raised against the gel-purified 33-kDa protein in a rabbit. The serum was termed monospecific antiserum (MSA) and was used in subsequent experiments. The MSA reacted specifically with all virulent strains of BDB in agglutination tests and colony blot tests but not or only weakly with Pseudomonas solanacearum, P. syzygii, and other bacterial species. The specificity of the MSA was confirmed in studies with banana plant extracts. BDB could be detected in all infected plants 3-33 days after inoculation, whereas plants inoculated with P. solanacearum race 2 did not react with the MSA on immunocolony blots

The efficiency of extraction of hydrogen bacteria from soil for plate counting was evaluated by using pure cultures adsorbed to sterilized soil. The utilization of model materials which interact with bacteria by adhesive, capillary or electrostatic forces and the use of extraction fluids with buffering, detergent or chelating activity demonstrated the major importance of capillary forces for the retention of hydrogen bacteria. Utilization of Tris buffer (pH 7.5) as extraction fluid and separation of extracted bacteria from soil particles by sedimentation for 15 min resulted in the highest recovery. A second extraction step including sonication did not increase the efficiency. The extraction efficiency of 8 different strains of hydrogen bacteria adsorbed to 3 different soils demonstrated a high degree of variation wih respect to bacterial strains, but not to soil types. The recovery was inversely related to cell parameters such as size, motility and slime formation.

Pseudomonas syringae pv. phaseolicola and P. syringae pv. syringae are the causal agents of halo blight and brown spot disease, respectively, of Phaseolus vulgaris. Generalized Tn5 transposon mutagenesis was used to identify mutants that have either attenuated or completely lost pathogenicity. An EcoRI fragment bearing Tn5 from 3 of 4 mutants from each pathovar has been cloned into pBR322. The site of Tn5 insertion has been mapped, and a restriction endonuclease site map has been constructed for each fragment. Physical and genetic maps have been developed for cosmid subclone pOSU3105, which complements the Tn5 Path- mutation of PP9021 of pv. syringae. Site-directed mutagenesis and marker exchange of mutated sequences into the wild type strain identified a region within a 2.7 kb SalI fragment near one end of the insert in pOSU3105 that is essential for disease expression in beans. Another region which is located approximately 4.5 kb downstream is also essential. Southern blot hybridization with probes made from the Tn5-containing EcoRI fragments from two Path- mutants of pathovar syringae showed homology with restriction fragments from both pathovars. However a Tn5-containing EcoRI fragment from another mutant did not hybridize with DNA from one strain of pv. syringae nor with pv. phaseolicola DNA.

The major effort in molecular biology during the last two decades was to explain the structure and function of the eucaryotic genome. The investigators were able to establish a variety of recombinant DNA techniques which have a great potential for the application in animal breeding. cDNA- and genomic DNA-libraries and gene transfer techniques are the most important tools to diagnose and manipulate the genome. The first indication for possible application of gene transfer was successful expression of the MMT-growth hormone fusion gene in transgenic mice [7], but the following experiments in rabbits, pigs, sheep, and cattle [2, 4, 1] reduced the great expectations. The recent data about controlled, tissue specific expression of the transferred milk protein gene for ovine β-lactoglobulin [8] in mice suggest that manipulation of milk composition and changing of technological properties of milk proteins could be of interest for practical animal breeding [3].

Pseudomonas syringae pv. syringae (Pss) strain Pa129, which produces syringomycin or other toxic compounds, causes brown spot disease of bean, Phaseolus vulgaris. A genomic clone bank was constructed of Pal29 DNA using the broad host range cosmid vector, pVK102. Following conjugative transfer of the clone bank into strain R32, a syringomycinless Pss, none of the transconjugants inhibited the growth of Ceratocystis fimbriata. However, an E. coli colony from the clone bank slightly inhibited growth of the fungus. The cosmid, pOSU2901 (29 kb insert) in this colony could not be transferred intact from E. coli to Pss, strain R32 or to the pathovar phaseolicola. All transconjugants contained a cosmid that had the insert deleted. Evidence strongly supports the premise that the insert is usually precisely excised by a mechanism which restores the cloning site within the kanamycin gene of pVK102.