May 10, 2018

The fight against virus transmission by sap-feeding insects

Working for the Madrid based National Research Council in the Insect Vectors of Plant Pathogens group, Professor Alberto Fereres has been at the forefront of insect pest control research for nearly three decades. Heading up a team of 12, he is currently undertaking a vital research programme into control strategies for sap-feeding insect pests with a focus on the transmission of plant pathogens by insect vectors.

‘Insects cause more damage through transmitting viruses than the direct damage they inflict on crops’, says Professor Fereres. ‘It’s crucial therefore that we can control the insects before they have a chance to transfer the virus to the plants’.

‘Sap-feeding insects fall into two camps – those that feed on the phloem and those that feed on the xylem’, he continues. ‘Much of our work involves monitoring resistance in the insects to various insecticides. Approximately 6 years ago we began working with Isoclast looking specifically at aphid and whitefly populations’.

Both species feed on the phloem where the virus gets transferred to the plant. The team found that Isoclast caused the insects to alter their feeding behaviour. ‘It’s a real breakthrough because this alteration in how the insects fed meant reduced access to the phloem. This disruption to feeding meant that the virus was less likely to be transmitted, Professor Fereres confirmed.

The research also found that there was no cross resistance from similar groups of insecticides to Isoclast, leading Professor Fereres to conclude ‘ We’ve been able to confirm that Isoclast has the ability to reduce plant pathogen transmission by altering the feeding behaviour of sap-feeding insect pests including those that have resistance to other products. With this success behind us we can now look forward to our next project focusing on xylem feeders – the spittlebugs’.