Battling plant-virus superspreading by humans

A critical factor in viral disease outbreaks is the distribution and spread of the hosts, vectors and viruses themselves. The recent Covid pandemic has shown that the high rate at which the virus spread was caused by unbridled travelling of humans across the globe. Similarly, to exploit favorable climate and labor conditions, man also carries large numbers of many cultivated plant species around the same globe, causing a rapid spread of plant pathogens, thus increasing the risks of disease outbreaks among agricultural crops and ornamentals. As example for recognition of this problem, this summer, European governments requested vacationers not to bring plants home to prevent the spread of the bacterium Xylella fastidiosa and in the USA government restricts firewood introduction in their national parks to limit introduction and spread of all sorts of forest pests. The risks of human induced spread of plant viruses to staple food crops such as maize, rice, wheat, potato, sweet potato, and banana have recently been recognized. 

There are way more phytoviruses than vertebrate viruses, yet the focus of research and fight against viruses is clearly on the latter type. However, over the last decades, the battle between the hosts and phytoviruses tipped clearly to the viruses due to huge host reservoirs of cultivated plants plus the constant exposure to exotic viruses. This accelerated phytovirus evolution, is bad news for cultivated plants and thus the global food supply, but also for all other naturally occurring plants and thus local biodiversity.

The first step to turn the tide is to chart the problem. Fortunately, recent developments in molecular biology, such as high-throughput sequencing have made identifying new virus variants or completely new virus strains feasible. In recent years we have developed a comprehensive method (ViSiR) to identify (variants of) known phytoviruses and discover new phytoviruses by a combination of massive parallel smallRNA-sequencing of siRNAs from the plant virus defense with an advanced bioinformatics pipeline including all known virus sequences. With our ViSiR approach, we propose a project in which we, with a combination of molecular biology and artificial intelligence methods, are going to, on a large scale, identify yet unknown phytoviruses, investigate the mutation rate of plant viruses, and record the introduction of exotic virus variants in cultivated plants that are carried around the globe. Although we already employ our ViSiR approach on a small scale for Dutch plant-breeding companies, we would like to extend this method to make our approach available to all companies that use different locations around the world to cultivate their crops or ornamentals.

Point of contact for this research line

Dr Martijs Jonker
m.j.jonker at uva.nl
T 020-525-7939