New Zealand Plant Protection 66 (2013): 386
Sulphur is mainly used as a fungicide but is known to have insecticidal properties against some insect pests. A series of laboratory studies was conducted to assess its effect on the tomato potato psyllid (Bactericera cockerelli; TPP), a recently established pest species in New Zealand that transmits the bacterium Candidatus Liberibacter solanacearum (Lso). Short assays (≥ 24 h) using dipped leaves indicated that fresh sulphur residues had no discernible impact on TPP settlement patterns or onleaf behaviour. However, longer assays (≥ 72 h) using whole plants indicated that sulphur residues can disrupt egg-laying behaviour, but the effect was dependent on the assay design. In 72 h choice assays, TPP laid fewer eggs on plants sprayed with sulphur compared with control plants. In no-choice assays sulphur residues did not consistently reduce egg-laying. Together these results suggest that sulphur may slow the build-up of TPP populations within crops by deterring egg-laying. However, the lack of repellence or anti-feeding properties means that sulphur treatments alone may not be sufficient to prevent the transmission of Lso by TPP.
Copyright © 2013 New Zealand Plant Protection Society (Inc.).