Agriculture and Agri-Food Canada

About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.

Effects of benzoic and cinnamic acids on membrane permeability of soybean roots.

Abstract: Benzoic (BEN) and cinnamic (CIN) acids are commonly found in soils and are considered as strong allelochemicals. Published information suggest that BEN and CIN and other phenolic acids decrease plant growth in part by suppressing nutrient absorption. However, studies on the mechanism of action were not conclusive. We examined the effects of BEN and CIN on the cell plasma membrane in intact soybean (Glycine max L. cv. Maple Bell) seedlings. Treating intact root systems with BEN or CIN rapidly increased electrolyte leakage and ultraviolet absorption of materials into the surrounding solution. After 12 hr of treatment, BEN and CIN lowered the extracellular sulfhydryl group content in roots. The two allelochemicals induced lipid peroxidation, which resulted from free radical formation in plasma membranes, inhibition of catalase and peroxidase activities, and sulfhydryl group depletion. Oxidation or cross-linking of plasma membrane sulfhydryl groups is the first mode of action of both compounds. The BEN- and CIN-induced decrease in soybean nutrient absorption may be a consequence of damage to cell membrane integrity caused by a decrease in sulfhydryl groups followed by lipid peroxidation.

Corn response to nitrogen is influenced by soil texture and weather

Abstract: 3 Soil properties and weather conditions are known to affect soil nitrogen (N) availability and 4 plant N uptake. However, studies examining N response as affected by soil and weather 5 sometimes give conflicting results. Meta-analysis is a statistical method for estimating treatment 6 effects in a series of experiments to explain the sources of heterogeneity. In this study, the 7 technique was used to examine the influence of soil and weather parameters on N responses of 8 corn (Zea mays L.) across 51 studies involving the same N rate treatments which were carried out 9 in a diversity of North American locations between 2006 and 2009. Results showed that corn 10 response to added N was significantly greater in fine-textured soils than in medium-textured 11 soils. Abundant and well-distributed rainfall and, to a lesser extent, accumulated corn heat units 12 enhanced N response. Corn yields increased by a factor of 1.6 (over the unfertilized control) in 13 medium-textured soils and 2.7 in fine-textured soils at high N rates. Subgroup analyses were 14 performed on the fine-textured soil class based on weather parameters. Rainfall patterns had an 15 important effect on N response in this soil texture class, with yields being increased 4.5-fold by 16 in-season N fertilization under conditions of “abundant and well-distributed rainfall.” These 17 findings could be useful for developing N fertilization algorithms that would allow for N 18 application at optimal rates taking into account rainfall pattern and soil texture, which would lead 19 to improved crop profitability and reduced environmental impacts. 20