Towards the biocontrol of bindweeds with a mycoherbicide

Within the framework of the European COST Action 816, a five-year collaboration between scientists from five European countries has made an important contribution to biological control of field and hedge bindweeds (Convolvulus arvensis and Calystegia sepium, respectively). A fungus Stagonospora convolvuli strain LA39, able to infect both field and hedge bindweed, was found in the UK and its biocontrol efficacy improved by optimising mass production, formulation and storage techniques. This fungus controlled bindweeds in both a cemetery and in maize crops. Its use fits best in an integrated pest management system where a green cover controls most of the weeds except the bindweeds. DNA marker analyses indicate that the fungus reproduces sexually, which could be used to further improve this mycoherbicide. In addition, the insect Melanagromyza albocilia, which itself exhibits biocontrol potential against bindweeds, may be used in combination with LA39 to improve the ability of the fungus to penetrate the stem of bindweeds. Overall, the results suggest that S. convolvuli LA39 has promising potential as a bioherbicide for control of field and hedge bindweed.