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Monolepta hieroglyphica (Motschulsky, 1858) has been recently revised as the synonym of M. signata (Oliver, 1808) based on morphological characteristics. M. quadriguttata (Motschulsky, 1860) was synonymized with M. signata over 100 years ago. However, this synonymy has not be confirmed by molecular data. This widely distributed and abundant species shows a high variability in coloration patterns that caused numbers of synonyms. We selected color forms typical for the three nominal taxa for phylogenetic analysis. The phylogenetic, haplotype and genetic differentiation analysis of M. hieroglyphica, M. quadriguttata and M. signata were constructed to determine the relationships between them, and we also found mating behavior between them. They were intermixed together on phylogenetic trees, and M. hieroglyphica and M. quadriguttata had shared haplotype. There was no significant difference among them for genetic distance, and the synonymy of the three names based on external and genital characters can be confirmed by molecular data. [ABSTRACT FROM AUTHOR]

The fungal pathogen Setosphaeria turcica causes leaf blight on maize, which leads to considerable crop losses. However, how S. turcica establishes sustained systemic infection is largely unknown. Here, we report several novel factors contributing to S. turcica pathogenicity, identified using a genomic and transcriptional screen at different stages of S. turcica appressorium development. We identified two cytoskeleton regulators, SLM1 and SLM2, that are crucial for hypha and appressorium development. The SLM1 and SLM2 transcripts accumulated during germling stage but their levels were notably reduced at the appressorium stage. Deletion of SLM2 dramatically affected cell morphology, penetration ability, and pathogenicity. We also identified three different types of S. turcica glycosyl hydrolases that are critical for plant cell wall degradation. Their transcripts accumulated during the appressorium infection stage induced by cellophane and maize leaf. Most importantly, we characterized a novel and specific S. turcica effector, appressorium‐coupled effector 1 (StACE1), whose expression is coupled to appressorium formation in S. turcica. This protein is required for maize infection and induces cell death on expression in Nicotiana benthamiana. These observations suggest that the phytopathogen S. turcica is primed in advance with multiple strategies for maize infection, which are coupled to appressorium formation at the early infection stages. [ABSTRACT FROM AUTHOR]

We examine the effect of litigation risk on management’s decision to issue earnings forecasts. We use a new ex ante measure of litigation risk, namely, the Directors and Officers liability insurance premium. This measure bypasses significant problems associated with the estimation of ex ante litigation risk in prior studies. By using this measure of litigation risk, our results are more intuitive. We find that, when faced with ex ante litigation risk, managers with bad news are more likely to issue an earnings warning. For good news firms, we do not see this effect. We also examine three forecast characteristics: forecast horizon, amount of news revealed, and forecast precision. Firms with higher litigation risk tend to issue earnings forecasts earlier if they have bad news, but they do not issue forecasts earlier or later with respect to good news. They also reveal less news in the forecasts if they have good news. As litigation risk increases, bad news earnings forecasts tend to become more precise while good news earnings forecasts tend to become less precise. This differential effect of litigation risk on management earnings forecasts, based on the direction of the news, has not been documented by previous studies. [ABSTRACT FROM AUTHOR]

Laccases are multicopper oxidases (E.C. 1.10.3.2) that catalyze the oxidation of many phenolic compounds. In this study, a novel laccase, Stlac4, from Setosphaeria turcica was cloned and expressed in Escherichia coli by insertion into the pET-30a expression plasmid. The recombinant laccase was purified and visualized on SDS-PAGE as a single band with an apparent molecular weight of 71.5 KDa, and confirmed by Western blot. The maximum activity of the purified laccase was 127.78 U · mg−1, the optimum temperature and pH value were 60 °C and 4.0 respectively, measured by oxidation of 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS). Purified laccase activity under different metal ions and an inhibitor were tested, revealing that laccase activity increased by approximately 434.8% with Fe3+, and 217.4% with Cu2+ at 10 mmol · L−1 concentrations, Mn2+ increased the laccase activity only at 5 mmol · L−1, while Na+ increased activity at 1 mmol · L−1 but inhibited activity at 5 and 10 mmol · L−1. SDS increased laccase activity at 1 mmol · L−1, and inhibited activity at 5 and 10 mmol · L−1. [ABSTRACT FROM AUTHOR]