Blackberry: Exploring whether redberry disease is caused by a mite-transmitted virus


Red berry disease is causing serious damage and losses in commercial blackberry plantations world wide, particularly in high value crops established in tunnels as the warm dry conditions created provide an ideal habitat for the blackberry mite. A typical blackberry crop can be worth up to £10,000 a tonne and in recent trials carried out in 2011 up to 41% of fruit was categorised as outgrade due to red berry symptoms. Having a better understanding of the cause of this condition in order to inform strategies for control could represent a huge financial benefit to the blackberry industry, not to mention improving the quality of product on the shelf for the consumer.

Trials to date looking at acaricides for the control of the blackberry mite thought to be responsible for this condition have shown little control of red berry despite good mite control. This suggests either something other than the mite is causing the condition or that the mite is transmitting something which is systemic in the plant and causing significant damage with relatively low mite levels. This project will carry out in-depth sequencing of plant tissues affected by red berry to try to identify whether a virus is responsible for this condition and whether the blackberry mite is transmitting it. Finding out if the condition is indeed virus-borne will inform control and could lead on to screening different blackberry genotypes to look for tolerance or resistance to the virus.

Benefits to the industry:
Understanding the cause of red berry disease will give growers the ability to better protect their crops. This will lead to a better yield, increasing the value of the product for both the grower and the industry and creating a consumer product of a higher quality.
Project code:
SF 149
01 April 2014 - 30 August 2015
AHDB Horticulture
AHDB sector cost:
Project leader:


SF 149_GS_Final_2015 SF 149_Report_Final_2015

About this project

Aims and objectives:

Project aim: To discover if a virus is responsible for red berry disease in blackberry
Project objectives:
• Carry out RNA mass analysis on a range of tissues of affected blackberry to determine if an unknown virus is present;
• If a virus is identified, then design a specific RT-PCR test that can be used to analyse further plants as well as mites (to confirm whether the black berry mite (Acalitus essigi) also carries the virus);
• Disseminate findings to panel members through the project report and an article in AHDB Grower or presentation at an event.