Evaluation of Tween 20® and glycerol as additives to mycoherbicide suspensions applied to Bathurst burr

T.A. Klein and B.A. Auld, NSW Agriculture, Agricultural Research and Veterinary Centre, Orange, New South Wales 2800, Australia.


Suspensions of Colletotrichum orbiculare have been applied as an experimental mycoherbicide to successfully control Bathurst burr (Xanthium spinosum). Tween 20® and glycerol were assessed in field trials as additives to spore suspensions in an attempt to improve plant kill by C. orbiculare. Suspensions were mixed on site and applied at dose rates of zero, 1010, 1011 and 1012 spores ha-1. High per cent (>76%) kill was achieved in four of seven trials. Neither Tween 20 nor glycerol offered any improvement over water as a sole liquid carrier at any site. Higher spore dose rates were associated with increased plant kill.


Plant Protection Quarterly (1995) 10 (1) 14-16.