Soltani, N., Nurse, R. E., Robinson, R. E. and Sikkema, P. H. 2011. Effect of ammonium sulfate and water hardness on glyphosate and glufosinate activity in corn. Can. J. Plant Sci. 91: 1053–1059. Eight field trials were conducted over a 3-yr period (2008 to 2010) near Harrow and Ridgetown, Ontario, to evaluate the effect of water hardness (distilled: 0 ppm; intermediate: 353 ppm; and very hard 1799 ppm) on full label doses of glyphosate (900 g a.e. ha−1) and glufosinate (400 g a.i. ha−1) [with and without ammonium sulfate (AMS) at 2.5 L ha−1] efficacy in corn. There was no effect of water hardness on control of velvetleaf (ABUTH), redroot pigweed (AMARE), common lambsquarters (CHEAL), and annual grasses green foxtail (SETVI) and barnyardgrass (ECHCG) when glyphosate was applied with or without the AMS. There was also no difference in yield of corn with various water sources when glyphosate was applied with or without AMS. Glyphosate applied with various water sources with or without AMS controlled ABUTH, AMARE, CHEAL, and annual grasses better than glufosinate with or without AMS. Glufosinate with AMS, especially at the 1799 ppm water hardness, generally controlled ABUTH, AMARE, and CHEAL better than glufosinate without AMS, but there was no improvement in annual grass control. Contrasts indicated an 11% increase in yield when glufosinate was applied with AMS compared with when applied without AMS. Based on these results water hardness and AMS had little benefit on the efficacy of glyphosate in corn; however, efficacy of glufosinate was improved when applied with AMS at high water hardness.

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LeClair, E., Conner, R., Robinson, D. and Gillard, C. L. 2015. Transmission of anthracnose (Colletotrichum lindemuthianum) in dry bean (Phaseolus vulgaris L.) with artificial and natural inoculum in a wet and dry canopy. Can. J. Plant Sci. 95: 913–921. Anthracnose [Colletotrichum lindemuthianum (Sacc. and Magn.) Lams. – Scrib.] is a serious pathogen of dry bean (Phaseolus vulgaris L.). Disease transmission on artificial materials and clothing has been observed in other crops, where equipment and workers transmit pathogens from infected to clean plants. Initial studies in 2008 and 2009 at Exeter, ON, determined that anthracnose transmission in dry bean as measured by resultant disease severity occurred with denim, leather, metal, and rubber using a 107 spores mL−1 prepared artificial spore inoculum in both wet and dry crop canopies. In 2012 and 2013 at Morden, MB, and Ridgetown, ON, the studies were expanded by adding a 105 spores mL−1 prepared artificial and a natural inoculum source. Inoculum source and canopy moisture had the greatest effect on disease severity, while no differences were observed between materials within an inoculum sources. Transmission in wet canopy conditions resulted in a higher infection rate. Canopy moisture impacted the natural inoculum the most. The 107 spores mL−1 inoculum transmitted the most disease followed by natural incidence and 105 spores mL−1 inoculum in wet conditions. In dry conditions 107 spores mL−1 inoculum transmitted the most disease followed by 105 spores mL−1 inoculum and natural incidence. Producers need to recognize that there is real risk for the anthracnose transmission by common materials in dry bean, and take appropriate precautions to prevent it.