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Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. We investigated the genetic diversity and reproductive biology of Colletotrichum graminicola isolates which infect maize by sequencing the genomes of 108 isolates collected from 14 countries using restriction site-associated DNA sequencing (RAD-seq) and whole-genome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms revealed three genetic groups delimited by continental origin, compatible with short-dispersal of the pathogen and geographic subdivision. Intra- and intercontinental migration was observed between Europe and South America, likely associated with the movement of contaminated germplasm. Low clonality, evidence of genetic recombination, and high phenotypic diversity were detected. We show evidence that, although it is rare (possibly due to losses of sexual reproduction- and meiosis-associated genes)

This chapter discusses the results of key interviews with Somalis regarding their perceptions about Al-Shabaab. Respondents expressed concerns about Al-Shabaab's indiscriminate and excessive use of violence, which are considered inconsistent with Islam, and its restrictions on freedom of speech and movement. However, they spoke positively about Al-Shabaab's strict enforcement of rules and their impartial resolution of disputes. They also compared Al-Shabaab favourably to the government in terms of reducing clan influence over politics or the allocation of resources, and in terms of minimizing corruption in ‘tax’ collection, but noted the group's failure to provide social services. Three-quarters of respondents expressed support for a negotiated solution to the conflict, but doubted Al-Shabaab would be willing to engage.

Members of the genus Colletotrichum cause anthracnose diseases on nearly every crop grown for food, fiber, and forage worldwide. Colletotrichum fungi display a broad range of lifestyles, including plant associations occupying a continuum from necrotrophy to intracellular hemibiotrophy (IH) to endophytism. There are at least three major variants of IH, differing in the duration of biotrophy and synchronization of the switch to necrotrophy. Comparative genomic analyses may uncover how these lifestyles evolved and their functional relationships, identify commonalities as potential conserved targets for control and management, and transform our current understanding of Colletotrichum taxonomy. The genome sequences of four species were recently published: C. graminicola; C. higginsianum; C. obiculare; and C. fructicola (reported as C. gloeosporioides). These species occupy distinct monophyletic lineages in the genus and represent three different lifestyles (two variants of IH, and necrotrophy). The Colletotrichum genomes are relatively large (58-88 Mb), and encode between 11,000 and 16,000 genes. They share little synteny, suggesting that large-scale genome rearrangements were common during the evolutionary history of the genus. Several gene families are expanded in Colletotrichum relative to other sequenced ascomycetes, including those encoding carbohydrate-active enzymes, secondary metabolism enzymes, secreted proteases, and putative secreted effectors. Analysis of the in planta transcriptomes of C. higginsianum, C. graminicola, and C. orbiculare suggested that appressoria and biotrophic intracellular hyphae function as platforms for the secretion of effectors and secondary metabolites to establish host compatibility, while hyphae developing after the switch to necrotrophy are primarily involved in secreting cell wall degrading enzymes and nutrient uptake.