Virulent pests and diseases that are ravaging Africa’s forests with profound intensity pose new threats to their survival, experts said at a forum in Entebbe, Uganda on Wednesday.

The spread of pests and pathogens that damage plant life could cost global agriculture $540 billion a year, according to this report released by the Royal Botanic Gardens in London. An increase in international trade and travel had left flora facing rising threats from invasive pests and pathogens, and called for greater biosecurity measures.

The prevailing paradigm of host-parasite evolution is that arms races lead to increasing specialisation via genetic adaptation. Insect herbivores are no exception and the majority have evolved to colonise a small number of closely related host species. Remarkably, the green peach aphid, Myzus persicae, colonises plant species across 40 families and single M. persicae clonal lineages can colonise distantly related plants. This remarkable ability makes M. persicae a highly destructive pest of many important crop species.

Rabat – Two new fungal diseases capable of destroying whole wheat crops around the world have been discovered, with crops in the Mediterranean at particular risk, according to a study conducted by

An infection that struck wheat crops in Sicily last year is a new and unusually devastating strain of fungus, researchers say — and its spores may spread to infect this year’s harvests in Europe, the world’s largest wheat-producing region.

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Rome — Wheat rust, a family of fungal diseases that can cause crop losses of up to 100 per cent in untreated susceptible wheat, is making further advances in Europe, Africa and Asia, according to t

RNA silencing is an adaptive, inducible antiviral defence mechanism in the host against invading viruses. The adaptive antiviral function is characterized by the formation of virus-derived small interfering RNAs (siRNAs) during viral infection. As a counter defense strategy, a number of plant viruses evolve viral suppressors to target antiviral silencing.

Existing theory, empirical, clinical and field research all predict that reducing the virulence of individuals within a pathogen population will reduce the overall virulence, rendering disease less severe. Here, we show that this seemingly successful disease management strategy can fail with devastating consequences for infected hosts. We deploy cooperation theory and a novel synthetic system involving the rice blast fungus Magnaporthe oryzae. In vivo infections of rice demonstrate that M.

Phytophthora infestans (Mont.) de Bary, the causal agent of potato late blight, was responsible for the Irish potato famine of the 1840s. Initial disease outbreaks occurred in the US in 1843, two years prior to European outbreaks. We examined the evolutionary relationships and source of the 19th-century outbreaks using herbarium specimens of P. infestans from historic (1846–1970) and more recent isolates (1992–2014) of the pathogen. The same unique SSR multilocus genotype, named here as FAM-1, caused widespread outbreaks in both US and Europe.

Climate change will have serious repercussions for agriculture, ecosystems, and farmer livelihoods in Central America. Smallholder farmers are particularly vulnerable due to their reliance on agriculture and ecosystem services for their livelihoods. There is an urgent need to develop national and local adaptation responses to reduce these impacts, yet evidence from historical climate change is fragmentary. Modeling efforts help bridge this gap. Here, we review the past decade of research on agricultural and ecological climate change impact models for Central America.

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