Mutations of the β‐tubulin gene fragments from carbendazim‐resistant isolates of Pestalotiopsis sp. causing strawberry leaf blight in Chiang Mai,Thailand

Screening of field isolates of Pestalotiopsis sp. from strawberry leaf blight in Thailand identified 56 carbendazim‐resistant isolates. Of 56 isolates, 39 highly resistant (HR) phenotypes grew well on PDA amended with carbendazim even at ≥500 mg/L. Isolates with carbendazim‐resistant phenotype had a conspicuous mutation at particular sites in the beta‐tubulin (β‐tubulin) gene sequence. A β‐tubulin encoding gene from this pathogen was cloned and sequenced. Analysis of the β‐tubulin gene in highly resistant (HR) isolates showed a substitution at codon 79 and 102 from serine (AGT) to lysine (AAA) and valine (GTA) to alanine (GCA), respectively. The detection of such point mutations in the β‐tubulin gene allows the rapid screening to detect carbendazim‐resistant isolates in the field.     

Synthesis and biological evaluation of novel thio-substituted chromanes as high-affinity partial agonists for the estrogen receptor.

Synthesis of (+/-)-cis-7-hydroxy-3-phenyl-4-(4-(2-piperidinoethanethio)phenyl)chromane (13) and (+/-)-cis-7-hydroxy-3-phenyl-4-(4-(2-pyrrolidinoethanethio)phenyl)chromane (15) is presented. These compounds are representatives of a novel class of compounds with high in vitro binding affinity for the estrogen receptor (IC(50)=7-10 nM), and very low in vitro uterotrophic activity (max stim.=5-17% rel to moxestrol; EC(50)=0.5-1.8 nM).     

Behavioural and chemical mechanisms of plant‐mediated deterrence and attraction among frugivorous insects

1. Herbivory often induces systemic plant responses that affect the host choice of subsequent herbivores, either deterring or attracting them, with implications for the performance of both herbivore and host plant. Combining measures of herbivore movement and consumption can efficiently provide insights into the induced plant responses that are most important for determining choice behaviour. 2. The preferences of two frugivorous stink bug species, Nezara viridula and Euschistus servus between cotton plants left undamaged or damaged by Helicoverpa zea and Heliothis virescens larvae were investigated. A novel consumer movement model was used to investigate if attraction rates or leaving rates determined preferences. Stink bug consumption rates were measured using salivary sheath flanges. Finally, the systemic induction of selected phenolic‐based and terpenoid secondary metabolites were measured from heliothine herbivory on developing cotton bolls, to investigate if they explained stink bug feeding responses. 3. Heliothine herbivory did not affect the N. viridula feeding preference. However, we found opposing effects of H. zea and H. virescens herbivory on the behaviour of E. servus. Avoidance of H. zea‐damaged plants is not obviously related to phenolic or terpenoid induction in cotton bolls; whereas a preference for H. virescens‐damaged plants may be related to reductions in chlorogenic acid in boll carpel walls. 4. The present results highlight the inferential power of measuring both consumer movement and consumption in preference experiments and combining behavioural responses with phytochemical responses. Furthermore, while plant‐mediated interactions among herbivorous insects are well studied, interactions among frugivorous species specifically have been poorly documented.     

Tightly Regulated Expression of Autographa californica Multicapsid Nucleopolyhedrovirus Immediate Early Genes Emerges from Their Interactions and Possible Collective Behaviors

To infect their hosts, DNA viruses must successfully initiate the expression of viral genes that control subsequent viral gene expression and manipulate the host environment. Viral genes that are immediately expressed upon infection play critical roles in the early infection process. In this study, we investigated the expression and regulation of five canonical regulatory immediate-early (IE) genes of Autographa californica multicapsid nucleopolyhedrovirus: ie0, ie1, ie2, me53, and pe38. A systematic transient gene-expression analysis revealed that these IE genes are generally transactivators, suggesting the existence of a highly interactive regulatory network. A genetic analysis using gene knockout viruses demonstrated that the expression of these IE genes was tolerant to the single deletions of activator IE genes in the early stage of infection. A network graph analysis on the regulatory relationships observed in the transient expression analysis suggested that the robustness of IE gene expression is due to the organization of the IE gene regulatory network and how each IE gene is activated. However, some regulatory relationships detected by the genetic analysis were contradictory to those observed in the transient expression analysis, especially for IE0-mediated regulation. Statistical modeling, combined with genetic analysis using knockout alleles for ie0 and ie1, showed that the repressor function of ie0 was due to the interaction between ie0 and ie1, not ie0 itself. Taken together, these systematic approaches provided insight into the topology and nature of the IE gene regulatory network.     

Glucosamine-6-phosphate synthase inhibiting C3-β-cholesterol tethered spiro heterocyclic conjugates: Synthesis and their insight of DFT and docking study

A series of novel covalent cholesterol-spiro pyrrolidine/pyrrolizidine heterocyclic hybrids possessing biologically active oxindole, indanedione, and acenaphthylene-1-one have been synthesized by the reaction of C3-β-cholesteroalacrylate with heterocyclic di- and tri-ketones. All the sixteen compounds were obtained as a single isomer in good yield through a stereo- and regio- selective 1,3-dipolar cycloaddition methodology. Stereochemistry of the spiranic cycloadducts has been established by spectroscopic analysis and the regioselectivity outcome of the spiro adducts has been accomplished by DFT calculations at B3LYP/6-31G (d,p) level study. In vitro antibacterial activity of the newly synthesized cycloadducts were evaluated against highly pathogenic Gram-positive and Gram-negative bacteria and the most active compounds 5a, 13, and 14 underwent automated in silico molecular docking analysis in order to validate their effective orientation as a inhibitors bound in the active site of glucosamine-6-phosphate synthase (1XFF) enzyme by employing AutoDock Tools.     

Taxonomic review of the tribe Anthocoptini (Acari: Eriophyidae) from Korea

Tribe Anthocoptini (Prostigmata: Eriophyidae) from Korea was reviewed. A total of eight species in the tribe were presented, among them, four species, Abacarus hystrix (Nalepa), Aculus fockeui (Nalepa and Trouessart), Aculus schlechtendali (Nalepa) and Tegolophus zizyphagus (Keifer) were newly recorded to the fauna. All the Korean species of the tribe were redescribed and illustrated. Keys to the Korean species of the tribe and distributions were also presented with the biological information such as host plants and damage symptoms.     

Synergistic effect of fumigation with ethyl formate and methyl salicylate on mortality of life stages of adzuki bean beetle,Callosobruchus chinensis (L.)

Ethyl formate (EF) is becoming an insecticide of choice for protecting stored commodities. Along with EF, methyl salicylate (MS) is also naturally occurring, and both are generally regarded as safe fumigants for their higher threshold limit values (TLV) and residual status below minimum residue limit (MRL). Sub-lethal doses of EF and MS were evaluated to determine if there was a synergistic effect on fumigation against life stages of the adzuki bean beetle, Callosobruchus chinensis (L.) infesting adzuki bean grains. Based on lethal dose (LD) values, the C. chinensis eggs and adults were equally susceptible to EF followed by larvae and pupae. Adults were the most MS-sensitive followed by eggs and larvae, and pupae were the most tolerant stage. The mortalities of all the life stages of C. chinensis by combined fumigation with sub-lethal EF and MS doses were significantly higher compared to the sum of their separate fumigations revealing a notable synergistic effect. Moreover, the maximum doses of EF and MS tested for synergistic fumigation test did not hamper the germination potential of adzuki been seeds. The synergistic effect between EF and MS can significantly reduce the dose rate of flammable EF against C. chinensis thereby offering a good prospect for EF + MS formulation as an alternative to safeguard stored adzuki bean.     

New lignans from leaves of Macropiper excelsum

Four new lignans, (+)-diayangambin; (+)-excelsin; (+)-epiexcelsin and (+)-demethoxyexcelsin, were isolated from leaves of Macropiper excelsum and their structures and configurations have been determined by spectroscopic studies. Diayangambin is only the second naturally occurring diaxially substituted 3,7-dioxabicyclo-[3,3,0]-octane to have been isolated.