Enhancement of the efficacy of a carbamate nematicide against the potato cyst nematode, Globodera pallida, through mycorrhization in commercial potato fields.

Two experiments were conducted over 2 years in commercial potato fields in Shropshire, UK, to evaluate the compatibility of the nematicide aldicarb with commercial inocula of arbuscular mycorrhizal fungi (AMF) in the control of the potato cyst nematode Globodera pallida. The AMF used were Vaminoc (mixed-AMF inoculum), Glomus intraradices (BioRize BB-E) and G. mosseae (isolate BEG 12). In the absence of AMF, the in-soil hatch of G. pallida increased 30% (P < 0.01) from wk-2 to wk-4 after planting. Inoculation of physiologically-aged potato (cv. Golden Wonder) tubers with AMF eliminated this delay in G. pallida hatch by stimulating a mean increase of 32% (P < 0.01) in hatch within 2 wk after planting. In the aldicarb-treated plots in Experiment 1, G. pallida multiplication rate was 38% lower (P < 0.05) in roots of AMF-inoculated than noninoculated plants, but in Experiment 2, this effect was slightly lower (P = 0.07). In these plots, the single AMF inocula showed also a weak trend (P = 0.10) towards greater tuber yields relative to their noninoculated counterparts. Mycorrhization therefore appears to enhance the efficacy of carbamate nematicides against G. pallida and consequently more research is proposed to validate these findings and fully explore the potential of this model.

Utilisation of inorganic salts in fungal crop disease management in the U.K.

The overaLl aim of the study described in this communication was to utilise the findings of a global scientific and technical literature survey on the use of inorganic salts against crop fungal diseases in order to assess the potential of using these substances to reduce the reliance of UK growers on conventional fungicides. A summary of the main findings of the Literature survey is provided followed by information on the current commercial use of inorganic salt-based products in fungal disease management. Finally, the scope of potential use of inorganic salts on high disease risk crops in the UK is assessed and specific crop/pathogen combinations are prioritised for further research.

Inorganic salts for suppressing powdery mildew in cucurbits--a worldwide survey.

The present review provides an update of recent progress in the use of inorganic salts to manage powdery mildew (Sphaerotheca fuliginea and Erysiphe cichoracearum) in cucurbits (Cucurbitaceae). A literature survey identified 16 salts, mainly bicarbonates (e.g. KHCO3), phosphates (e.g. K2HPO4) and silicates (e.g. Na2SiO3), as having potential to suppress powdery mildew in cucurbits. The percentage suppression compared with untreated controls was calculated from the best treatment of each of 20 peer-reviewed studies and this ranged from 41-99%. The high efficacy of inorganic salts in suppressing cucurbit powdery mildew coupled with the abundance of formulated inorganic salt-based products may enable a reduction in the number of conventional fungicide applications needed to control the disease. Overall, the survey revealed that spray or hydroponic applications of inorganic salts can be a useful component in the integrated management of cucurbit powdery mildew, leading to potential environmental and financial benefits.