The Influence of Ammonium Sulphate added to the Spray Solution of Calcium Carbonate-Containing Glyphosate and Nicosulfuron on Barnyardgrass and Velvetleaf Control

Document Type : Research Article


1 Ferdowsi University of Mashhad

2 Iranian Plant Protection Research Institute


Introduction: There are many reasons for no effectiveness of herbicides on weeds, including the incorrect herbicide, the insufficient use of herbicide, the unprincipled sprayer, spraying at the wrong time especially adverse weather conditions, and a factor that often overlooked is the "water quality in herbicide spray tank". Most of the herbicides are mixed with water and applied as a spray. Obviously water quality is an extremely important issue. Water quality factors in this regard that effect on uptake and translocation of herbicides included as water hardness, pH, bicarbonate ion concentration, turbidity, organic matter and other substances. Hardness is determined by the amount of calcium and magnesium present and is expressed as calcium carbonate (CaCO3) equivalent in parts per million. Petroff (27) classified water based on hardness: water with a hardness 0-75 ppm is considered “soft” water, 75-150 ppm is “medium hard”, 150-300 ppm is considered “hard”, and more than 300 ppm is “very hard”. Hard water is a problem in over 85% of the United States according to the US Geological Survey. The contrast between the herbicides and dissolved ions depend on amount and type of minerals in the spray tank. So that different herbicide may show different responses to the same action. If soft water is not available, surfactant and chemicals additives such as ammonium sulfate (AMS), ammonium nitrate (AMN) and urea- ammonium nitrate can be added to the spray tank to increase herbicide efficacy (7). These compounds prevent from the adverse effects of the ions in water. Glyphosate and nicosulfuron belong to two different chemical families of herbicides and are soluble in water. Therefore, water quality such as the presence of calcium carbonate may have a significant effect on these herbicide performances, while removing the inhibitory effect of water hardness by adding nitrogen compounds such as ammonium sulfate need to experiment. According to the above, basic experiments carried out as the influence of adding ammonium sulphate to spray solution of calcium carbonate-containing glyphosate and nicosulfuron on barnyardgrass and velvetleaf control.
Materials and Methods: Four experiments were performed as factorial arrangement of treatments 6×2 based on completely randomized design with six replications (+six control pots for each weed species) at Research Greenhouse of the Ferdowsi University of Mashhad in 2010. Factors were included different concentrations of calcium carbonate (CaCO3; Merck, Germany) of water in spray tank at six levels 0, 100, 200, 300, 400 and 500 ppm in deionized water (w/v) in combination with 0 (-AMS) or 3 kg/ha (+AMS) ammonium sulphate (Merck, Germany) as adjuster the hardness. Glyphosate (Roundup®) and nicosulfuron (Cruse®) herbicides were applied post emergent at 385 and 550 mL ha-1 as commercial products (158 and 22 g ai ha-1; based on ED50 outcome preliminary test (12), recpectively) at the 3-4 leaf stage of the weeds (barnyardgrass and velvetleaf) in a spray volume of 250 L ha-1. Four weeks after treatment, survival, plant height, leaf area, and shoot dry weight of weeds (% control) were calculated. The data of experiment were subjected to ANOVA using MSTATC software. Means of the treatments were separated using Duncan’s Multiple Range Test at α = 0.05. Also, based on the distribution of data, regression analysis was used as linear, two, and third-degree polynomial by EXCEL 2007.
Results and Discussion: The results showed a significant reduction (p≤0.01) for survival, plant height, leaf area, and shoot dry weight of weeds (% control) with addition of calcium carbonate in spray tank of glyphosate and nicosulfuron herbicides, but this effect was not similar. So that, 500 ppm Ca2+ to the nicosulfuron spray solution compared with its absence increased barnyardgrass and velvetleaf biomass (% control) 16 and 50%, respectively. The corresponding values for glyphosate were 78 and 51%. Accordingly, Nalewaja et al. (24) reviewed the effect of different calcium compounds such as calcium carbonate (0.02 mol) in water as a solvent nicosulfuron herbicide (15 g ai ha-1; 160 L ha-1) interaction to seven surfactants on finger grass (Digitaria sanguinalis L.) at greenhouse conditions found that CaCO3 across seven surfactants reduced about 8% nicosulfuron performance. In research conducted by Buhler and Burnside (5) concluded that an increase in calcium ion (prepared from CaCl2) to 2 mmol in spray tank was not affected on glyphosate (400 g ai ha-1; 190 L ha-1) performance. With the increasing of Ca++ to 8 mmol, was reduced significantly (P≤0.05) toxicity herbicide on oat (Avena sativa L.) from 80 to less than 20%, 14 days after spray at the greenhouse experiment. Adding ammonium sulphate (+AMS) decreased the antagonistic effects of water hardness, and increased herbicides efficacy on barnyardgrass and velvetleaf. However, the synergistic effect of +AMS on velvetleaf control by glyphosate was higher. Green and Cahill (10) concluded adding 2% AMS to spray tank increased the pH of nicosulfuron solution from 4.6 to 4.7 and finger grass was well controlled by this herbicide because of increasing nicosulfuron solubility from 12 to 16%. In research conducted by Mueller et al. (22), the presence of calcium (Ca++) and magnesium (Mg++) ions concentration of 250 ppm reduced the effectiveness of three types of glyphosate salt, but adding 2% by weight of ammonium sulfate (AMS) to the spray tank overcame to the ions antagonistic effect.
Conclusion: Results of current experiment emphasized the role of water hardness (CaCO3) in spray tank of glyphosate and nicosulfuron on barnyardgrass and velvetleaf control.


1- Aladesanwa R.D., and Oladimeji M.O. 2005. Optimizing herbicidal efficacy of glyphosate isopropylamine salt through ammonium sulphate as surfactant in oil palm plantation in a rainforest area of Nigeria. Crop Protection, 24: 1068-1073.
2- Altland J. 2001. Water quality affects herbicide efficacy. Available at (visited 22 February 2008)
3- Bernards M.L., Thelen K.D., and Penne D. 2005. Glyphosate efficacy is antagonized by manganese. Weed Technology, 19: 27-34.
4- Brown K. 2006. Environmental impact on herbicide performance. Manitoba Agriculture and Food, Pp. 440-443.
5- Buhler D.D., and Burnside O.C. 1983. Effect of water quality, carrier volume, and acid on glyphosate phytotoxicity. Weed Science, 31: 163-169.
6- Burgess P. 2003. Quality of pesticide spray water. Available at (visited 5 August 2009)
7- Caldwell J. 2007. Hard water can hinder chemical efficacy. Agriculture Online News and Features Editor.
8- Davis J.S. 1996. Integrated weed control in vegetable crops. In Proccedings Crop Protection in Northern Britian, Madison. Pp. 938.
9- Gherekhloo J. 2008. Tracing resistant Phalaris minor populations and studying their resistance mechanisms to Aryloxyphenoxy propionate herbicides in Fars and Golestan wheat field. Ph. D Thesis. Ferdowsi University of Mashhad.
10- Green J. M., and Cahill W.R. 2003. Enhancing the biological activity of nicosulfuron whit pH adjusters. Weed Technology, 17: 338-345.
11- Green J.M., and Hale T. 2005. Increasing and decreasing pH to enhance the biological activity of nicosulfuron. Weed Technology, 19:468-475. 16.
12- Hajmohammadnia Ghalibaf K., Rashed Mohassel M.H., Nassiri Mahallati M., and Zand E. 2011. Dose response of barnyardgrass (Echinochloa crus-galli L.) and velvetleaf (Abutilon theophrasti Medicus.) to glyphosate and nicosulfuron under greenhouse conditions. Journal of Plant Protection, 25(2): 202-213. (in Persian with English abstract)
13- Hall G.J., Hart C.A., and Jones C.A. 1999. Twenty-five years of increasing glyphosate use: the opportunities ahead. Pest Management Science, 56: 351-358.
14- Heidekamp A.J., and Lemley A.T. 2005. Hard water. Water quality program, College of human ecology, Cornell University.
15- Holm F.A., and Henry J.L. 2005. Water quality and herbicides. Available at (visited 18 October 2009)
16- Istvan D., and Endre M. 2009. Efficacy of herbicides influenced by spray carrier water pH and hardness. Journal of Agricultural Science. Debrecen. Pp. 141-146.
17- Jabbari H., and Zand E. 2006. Water quality is effective factor in improvement herbicides performance. Proceeding The First Conference of Environmental Engineering. Tehran.
18- Khan Z., and Thiem L.T. 2006. Optimizing coagulation and direct filtration processes for low turbidity, low temperature waters. Electron. Journal of Environment and Agriculture Food Chemistry, 5(3): 1395-1406.
19- Maschhoff J.R., Hart S.E., and Bladwin J.L. 2000. Effect of ammonium sulfate on the efficacy, absorption, and translocation of glufosinate. Weed Science, 48: 2-6.
20- Mcmullan P. 2000. Utility adjuvants. Weed Technology, 14: 792-797.
21- Mekki M., and Leroux G.D. 1994. Activity of nicosulfuron, rimsulfuron, and their mixture on field corn (Zea mays), soybean (Glycine max), and seven weed species. Weed Technology, 8: 436-440.
22- Mueller T.C., Main C.L., Thompson M.A., and Steckel L.E. 2006. Comparison of glyphosate salts (Isopropylamine, Demonism, and Potassium) and calcium and magnesium concentration on the control of various weeds. Weed Technology, 20: 164-171.
23- Nalewaja J.D., and Matysiak R. 1993. Spray carrier salts affect herbicide toxicity to kochia (Kochia scoparia). Weed Technology, 7: 154-158.
24- Nalewaja J.D., Praczyk T., and Matysiak R. 1995. Salts and surfactants influence nicosulfuron activity. Weed Technology, 9: 587-593.
25- Owens M.D.K. 1986. Evaluation of additives and rates of application for herbicides applied to soybean. North Cent. Weed Control Conf. Res. Rep., 43: 416-417.
26- Penner D. 2000. Activator adjuvants. Weed Technol., 14: 785-791.
27- Petroff R. 2000. Water quality and pesticide performance. Available at (visited 16 January 2010)
28- Smith A.M., and Vanden Born W.H. 1992. Ammonium sulfate increases efficacy of sethoxtdim through increased absorption and translocation. Weed Science, 40: 351-358.
29- Steinbauer G.P., and Grigsby B. 1959. Methods of obtaining field and laboratory germination of seeds of bindweeds, lady's thumb and velvetleaf. Weeds, 7: 41-46.
30- Sung S.S., Leather G.L., and Hale M.G. 1987. Development and germination of barnyardgrass (Echinochloa crus-galli) seeds. Weed Science, 35: 211-215.
31- Terra B.R.M., Martiny A.R., and Lindquistz J.L. 2007. Corn-velvetleaf (Abutilon theophrasti) interference is affected by sublethal doses of postemergence herbicides. Weed Science, 55: 491-496. 37.
32- Zand E., Nosrati I., Hajmohammadnia Ghalibaf K., and Jabbari H. 2014. Water quality effect on herbicides performance. p. 385-414. In Zand E., Mousavi S.K. and Heidari A. 2014. Herbicides and their applications (2nd edition by fundamental changes). Jahade Daneshgahi Mashhad Press. 552p.