Assessment of a potential bioproduct for controlling Cerotoma arcuata tingomariana (coleoptera: Chrysomelidae).

AIMS: The leaf-feeding pest Cerotoma arcuata tingomariana (Bechyné) (Coleoptera: Chrysomelidae) produces huge economic losses in different crops. This study aimed to produce conidia by semisolid-state fermentation and to establish the insecticidal activity of two formulation prototypes based on a native Beauveria bassiana isolate for controlling this pest. METHODS AND RESULTS: A novel fabric-based semisolid-state fermentation strategy for quick and large-scale conidia production was performed and characterized. Conidia were formulated as an emulsifiable concentrate (EC) and a water-dispersible granulate (WG). Afterwards, the mortality of C. a. tingomariana adults was assessed. A conidia concentration of 2.9 × 109 conidia cm-2 was obtained after 9 days-course fermentation and a yield of 33.4 g kg-1 dry-substrate. CONCLUSIONS: The polyester fabric-based fermentation is an efficient technique for producing and collecting B. bassiana spores. Regarding LC90 , the potency analysis showed that the EC was 21-fold more potent than the non-formulated conidia, and ~ 2.6-fold more potent than the WG. SIGNIFICANCE AND IMPACT OF STUDY: A high throughput fermentation based on polyester fabric as support for B. bassiana conidia production and subsequent formulation as an EC comprises a promising strategy for obtaining a bioproduct to control adults of C. a. tingomariana and other Chrysomelidae pests.

Use of Trichoderma koningiopsis chitinase to enhance the insecticidal activity of Beauveria bassiana against Diatraea saccharalis.

Trichoderma is a well-known soil-borne fungus, highly efficient producer of extracellular enzymes including chitinases. The aim of this study was to recover a chitinase from fermentation waste after harvesting Trichoderma koningiopsis Th003 conidia and assess its potential as an enhancer of Beauveria bassiana insecticidal activity against Diatraea saccharalis. T. koningiopsis was produced by solid fermentation, conidia were harvested, and a crude extract (CE) was recovered by washing the residual substrate (rice:wheat bran). The partially purified chitinase (PPC) (75 kDa product) with N-acetyl-ß-glucosaminidase activity was obtained by chromatography to 29.3-fold with optimal activity at pH 5 and 55°C. Both the CE and the PPC were mixed with B. bassiana Bv062 conidia and assessed in a bioassay against D. saccharalis larvae. The CE and PPC from T. koningiopsis Th003 did not affect the germination or viability of B. bassiana conidia and enhanced its insecticidal activity when used at 0.06 U/ml enzymatic activity with a 24.5% reduction in B. bassiana lethal time (LT90 ). This study demonstrated the potential of chitinases produced by T. koningiopsis in solid fermentation to be recovered from the waste substrate and used as an additive to enhance B. bassiana, adding value to the main waste from the Trichoderma biopesticide/biofertilizer industries.

Metarhizium rileyi biopesticide to control Spodoptera frugiperda: Stability and insecticidal activity under glasshouse conditions.

The insect-pathogenic fungus Metarhizium rileyi is highly sensitive to nutritional and environmental conditions which makes it difficult to produce as a stable biopesticide. In this study, a Colombian isolate of this fungus was produced in bulk, and conidia were formulated as an emulsifiable concentrate (EC). The stability of formulated conidia was studied. Conidial viability was maintained at >85 % viability for 12 m under refrigeration and for >three months at 18 °C. The pH values were stable, while contaminant content was significantly reduced. The efficacy of the EC to control Spodoptera frugiperda (Smith) was correlated with the storage time using different mathematical models, and conservative values of six and 12 months at 8 °C and 18 °C respectively, were established. Finally, the EC was evaluated in maize plants under glasshouse conditions. The LC50 and LC90 were estimated to be 1.17 × 104 and 4.03 × 106 conidia/mL respectively and a 57 % reduction in recent damage of plants was achieved. This study demonstrated the potential of M. rileyi formulated as EC to control S. frugiperda in maize. Therefore, it is necessary to continue developing this biopesticide, in order to deliver a new tool to be integrated in pest management programs.

Identification of Diatraea spp. (Lepidoptera: Crambidae) based on cytochrome oxidase II.

Diatraea spp. (Lepidoptera: Crambidae) are a group of insects that are agriculture pests in many economically relevant crops such as sugarcane, sorghum, corn and rice. Recognized species for this genus respond differentially to natural enemies used in their biological control, emphasizing the importance of species in a regional approach. Currently, identification is based on the male genitalia. However, the availability of specimens collected from field and subjectivity based on the character recognition can seriously hamper species identification, and therefore result in inadequate pest management. To overcome this, individuals of Diatraea spp. preliminarily classified male genitalia and obtained from reared conditions and the field (both derived from natural populations occurring in Colombia) were analyzed using genitalic morphometry and molecular biology specifically using a fragment of the cytochrome oxidase subunit II (CO II) mitochondrial gene. Although morphometric analysis did not show any overriding results regarding genitalia morphology, the bioinformatics analyses of CO II sequences resulted in an adequate classification of the individuals within the recognized species. It also, revealed that the occurrence of clades associated with geographical distribution may be associated with cryptic species. The latter was also confirmed by a Single-Strand Conformation Polymorphism (SSCP) methodology evaluating the same fragment of CO II. This experimental approach allows properly recognizing each species and in consequence is proposed as an effective tool in Diatraea species identification.

Memory and the creation of art: the syndrome, as in de Kooning, of 'creating in the midst of dementia'.

The creation of abstract art demands high intellectual capacities. Willem de Kooning, nonetheless, accomplished his last paintings while crippled by impairments diagnosed as Alzheimer's disease. Until my research neither art nor science offered an explanation, or a thinking method, for identifying this phenomenon, for solving a mystery that pertains to human discovery and creation. In this 'ArtScience' study of the de Kooning phenomenon I use 'Thinking Methods' which I devised by a systematic application of information on the workings of the brain, the 'Brain Methods'. With my 'Method of Observation' I examined de Kooning's paintings, created both before and during dementia, and found them comparable in technique and expression. This demonstrates the authenticity of art created in dementia. With my 'Cognitive Analysis' I identified in de Kooning the syndrome herein called 'Creating in the Midst of Dementia'. This Syndrome, unique in mechanisms and presentation, is characterized by (1) a specific combination of brain functions and malfunctions, in this case, preservation of three memory systems - working, procedural, and episodic - and deficit of the semantic memory system, and by (2) a response to precise stimuli, one that triggers brain reactivation, and as a consequence enables creating in the midst of dementia. My work offers: (1) The identification of the 'Syndrome of Creating in the Midst of Dementia'. It (a) presents its definition, the criteria of diagnosis, mechanism, rationale, and possibility of 'cognitive repair' and (b) solves the mystery of de Kooning creating art while crippled by dementia. (2) New Thinking Methods, the 'Brain Methods', that based on information on the workings of the brain, open a new path in the pursuit of truth. The 'Method of Observation' serves to define stimuli, and the 'Cognitive Analysis' to assess cognitive faculties. (3) The integration of art and science into a new discipline of study, 'ArtScience'.

Which adolescents are most receptive to tobacco industry marketing? implications for counter-advertising campaigns.

This study sought to identify adolescents most receptive to tobacco advertising based on individual differences in novelty-seeking personality and other key variables. Confidential self-report surveys were completed by 1,071 high school freshmen at 5 public high schools. The survey included validated measures of novelty-seeking personality, smoking habits, peer and family smoking, and tobacco advertising receptivity. Multiple logistic regression analysis was used to evaluate the independent associations of these variables and demographics with receptivity to tobacco advertising. Of the ninth graders, 44% had moderate to high levels of advertising receptivity and 54% had minimal to low levels of receptivity. Higher levels of receptivity were associated with ever smoking (odds ratio [OR] = 2.59, confidence interval [CI] = 1.99-3.39) and novelty-seeking personality (OR = 2.14, CI = 1.57-2.93). The association of novelty-seeking personality and tobacco advertising receptivity was most pronounced among adolescents who had never had a puff of a cigarette. Counter-advertising messages should consider individual differences in novelty-seeking, because novelty-seekers may be most receptive to tobacco industry promotional campaigns.