Comparative growth and efficacy of Trinidadian strains of Isaria fumosorosea blastospores for controlling Trialeurodes vaporariorum on bean plants

The comparative growth and efficacy of three strains of Trinidadian Isaria fumosorosea Wize (T, T10 and T11) blastospores were assessed as spray suspensions for controlling greenhouse whitefly, Trialeurodes vaporariorum Westwood. Percent germination of all the three strains were unaffected by the surfactants Triton X -100 or Tween 80 compared to the control (water). Radial growth of fungal strain T11 was faster than either T or T10 which were similar in their growth patterns. Virulence of blastospores of three strains were tested against pharate adult greenhouse whiteflies on bean plants (Phaseolus vulgaris L.). The corrected mortality of whitefly for strains T, T10 and T11 was 56, 68 and 98% at 107 blastospores mL-1 and the median lethal concentration observed was 2.1 x 107, 1.3 x 107 and 2.5 x 106 blastospores mL-1, respectively. Strain T11 was the most virulent (range: 97-98% mortality) and had the lowest LC50 (range: 1.1-2.5 x 106 viable blastospores mL-1) value of the Trinidadian blastospore treatments tested against greenhouse whitefly on P. vulgaris

Effect of photoperiod and host distribution on the horizontal transmission of Isaria fumosorosea (Hypocreales: Cordycipitaceae) in greenhouse whitefly assessed using a novel model bioassay

A model bioassay was used to evaluate the epizootic potential and determine the horizontal transmission efficiency of Isaria fumosorosea Trinidadian strains against Trialeurodes vaporariorum pharate adults under optimum conditions (25±0.5°C, ~100% RH) at two different photoperiods. Untreated pharate adults were arranged on laminated graph paper at different distributions to simulate varying infestation levels on a leaf surface. Four potential hosts were located 7, 14 and 21 mm away from a central sporulating cadaver simulating high, medium and low infestation levels, respectively. Percent hosts colonized were recorded 7, 12, 14 and 21 days post-treatment during a 16- and 24-h photophase. After 21 days, mean percent hosts colonized at the highest, middle and lowest infestation levels were 93 and 100%, 22 and 58%, 25 and 39% under a 16- and 24-h photophase, respectively. From the results, it was concluded that the longer the photophase, the greater the percentage of hosts colonized, and as host distance increased from the central sporulating cadaver, colonization decreased. The use of this novel model bioassay technique is the first attempt to evaluate the epizootic potential and determine the horizontal transmission efficiency of I. fumosorosea Trinidadian strains under optimal environmental conditions at different photoperiods. This bioassay can be used to assess horizontal transmission efficiency for the selection of fungi being considered for commercial biopesticide development

Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

Genetic architecture of spatial electrical biomarkers for cardiac arrhythmia and relationship with cardiovascular disease

The 3-dimensional spatial and 2-dimensional frontal QRS-T angles are measures derived from the vectorcardiogram. They are independent risk predictors for arrhythmia, but the underlying biology is unknown. Using multi-ancestry genome-wide association studies we identify 61 (58 previously unreported) loci for the spatial QRS-T angle (N = 118,780) and 11 for the frontal QRS-T angle (N = 159,715). Seven out of the 61 spatial QRS-T angle loci have not been reported for other electrocardiographic measures. Enrichments are observed in pathways related to cardiac and vascular development, muscle contraction, and hypertrophy. Pairwise genome-wide association studies with classical ECG traits identify shared genetic influences with PR interval and QRS duration. Phenome-wide scanning indicate associations with atrial fibrillation, atrioventricular block and arterial embolism and genetically determined QRS-T angle measures are associated with fascicular and bundle branch block (and also atrioventricular block for the frontal QRS-T angle). We identify potential biology involved in the QRS-T angle and their genetic relationships with cardiovascular traits and diseases, may inform future research and risk prediction

Multi-ancestry GWAS of the electrocardiographic PR interval identifies 202 loci underlying cardiac conduction

The electrocardiographic PR interval reflects atrioventricular conduction, and is associated with conduction abnormalities, pacemaker implantation, atrial fibrillation (AF), and cardiovascular mortality. Here we report a multi-ancestry (N = 293,051) genome-wide association meta-analysis for the PR interval, discovering 202 loci of which 141 have not previously been reported. Variants at identified loci increase the percentage of heritability explained, from 33.5% to 62.6%. We observe enrichment for cardiac muscle developmental/contractile and cytoskeletal genes, highlighting key regulation processes for atrioventricular conduction. Additionally, 8 loci not previously reported harbor genes underlying inherited arrhythmic syndromes and/or cardiomyopathies suggesting a role for these genes in cardiovascular pathology in the general population. We show that polygenic predisposition to PR interval duration is an endophenotype for cardiovascular disease, including distal conduction disease, AF, and atrioventricular pre-excitation. These findings advance our understanding of the polygenic basis of cardiac conduction, and the genetic relationship between PR interval duration and cardiovascular disease

Effects of Paecilomyces fumosoroseus and Encarsia formosa on the control of the greenhouse whitefly: preliminary assessment of a compatability study

The effect of separate and combined activity of Paecilomyces fumosoroseus Wize (Brown and Smith) Trinidadian strain T11 and the parasitoid, Encarsia formosa Gahan, was assessed on populations of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood), infesting Phaseolus vulgaris L. (French bean) and Pelargonium x domesticum (regal geranium) plants in replicate experiments. When infested bean and geranium plants were exposed to E. formosa for 2 days, and 4 days later sprayed with P. fumosoroseus blastospores, whitefly percent mortality was 99.5% and 75.5%, 94.6% and 59.4% for experiments 1 and 2, respectively. Treatment of infested bean plants with either E. formosa or P. fumosoroseus resulted in 87.8% and 78.7%, 73.1% and 97.0% whitefly mortality for experiments 1 and 2, respectively, while similar treatment of infested geranium plants resulted in 9.2% and 52.8%, 34.3% and 64.5% whitefly mortality for experiments 1 and 2, respectively. Our results support the use of E. formosa and P. fumosoroseus in combination in Experiment 1 for the treatment of whitefly infested P. vulgaris plants since a significant difference in mortality is observed than when either E. formosa or P. fumosoroseus is applied alone. However, in experiment 2, the combination treatment on P. vulgaris was no more effective than spraying P. fumosoroseus alone. On P. x domesticum plants, only P. fumosoroseus alone is needed for efficient control of the whitefly compared to the combination treatment. The relative timing of parasitoid oviposition and fungal infection are critical in determining the outcome of the interaction and are plant host dependent