Aims:  To investigate the inhibition potential of leaf‐associated bacteria against the pathogen of bacterial leaf spot of Euphorbia pulcherrima. Methods and Results:  Seven out of 200 bacterial strains were effective antagonists by in vitro screening and the two strains PAB241 and PAB242 significantly reduced the disease incidence and severity as foliar treatments of E. pulcherrima. The two effective strains, PAB241 and PAB242, were both identified as Bacillus amyloliquefaciens by a polyphasic approach including phenotypic feature, carbon source utilization profile, fatty acid methyl esters and analysis of 16S rRNA gene sequence. In addition, the suspensions of B. amyloliquefaciens PAB241 and PAB242 showed antibacterial activities against the pathogen of bacterial leaf spot of E. pulcherrima under different treatments. Conclusions:  The leaf‐associated bacteria, B. amyloliquefaciens PAB241 and PAB242, markedly inhibited the growth of X. axonopodis pv. poinsettiicola under different treatments and protected E. pulcherrima from pathogen infection in growth chamber conditions. Significance and Impact of the Study:  This is the first study that showed B. amyloliquefaciens from plant leaves was a potential bactericide against bacterial leaf spot of E. pulcherrima.

The stickiness of sludge during the drying process is an effect of its adhesion and cohesion. Furthermore, the adhesion and cohesion characteristics of sludge are comprehensive results of sludge components and their correlation with moisture. This work presents a simple method to test the adhesion and cohesion characteristics of sludge during the drying process based on the Jenike shear test. The results show that the most significant sludge adhesion and cohesion emerges at a moisture content of approximately 45 to 70% and 30 to 60%, respectively, and at a heating temperature of 120 C. An increase of the heating temperature to 200 C only brings a small movement to the sticky range location. The possible reasons for sludge adhesion and cohesion are discussed based on the results of sludge component analysis. The contributions of mineral materials with tiny particle sizes and metal salts to the adhesion and cohesion are discussed in this study because the contribution of organic matter has been widely demonstrated. The adhesion and cohesion nature of sludge exhibits a large effect on its drying characteristics. A remarkable fluctuation of both the drying rate and stirring power, located between the first and second falling rate period, is observed when the adhesion force of sludge reaches the maximum. When the sludge cohesion force decreases to approximately 3800 N/m 2 , sludge bulks are broken with the stirring of paddles.

Symptoms observed on Acer negundo (ashleaf maple, box elder) at several sites in Poland included reduced apical growth, severe leaf malformation and necrosis, witches' broom and dieback of twigs and branches. Leaves were sparse or in tufts at the tips of the shoots, and trees died within a few years of the onset of symptoms. Young (<3-year-old) trees of cv. Flamingo, growing in two nurseries, showed less severe shoot proliferation, leaf chlorosis or reddening, malformation of newly expanding leaves and stunting.Chip-grafting from affected A. negundo hybrids to 15 healthy Catharanthus roseus (periwinkle) resulted in two plants with very narrow, etiolated branches; whose symptoms developed slowly over 13 months. The remaining 13 periwinkles developed small, chlorotic leaves. Nucleic acids were extracted from sprouts and leaves by the method of Ahrens & Seemüller (1992). A nested PCR was done using the universal phytoplasma rDNA primer pair P1/ P7, followed by primers fA / rA, R16F2n / R16R2 or the phytoplasma rRNA 16SrI group-specific primers R16(I)F1/ R16(R1)R1. RFLP analysis of R16F2n/R16R2-primed PCR products was done using Alu I, Mse I and Rsa I endonucleases. Phytoplasma rDNA was amplified from five A. negundo hybrids, two cv. Flamingo, two apparently healthy 2-year-old seedlings collected from a park, two C. roseus experimentally inoculated by grafting with etiolated symptoms; and two C.

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