Evaluating Organic Acids in Canola-Soybeans Crop Rotation
Kevin Shale, Montra Crop Science
The current project is planned to determine if efficacy of post emergence herbicides and crop
fertilizers can be enhanced when used in conjunction with organic acid products. This project is
evaluating the effects of organic acid products (MX-3, VX-8) on Canola-Soybeans crop rotation.
Organic acid products (MX-3 & VX-8) evaluated in this study did not exhibit any effect on canola growth and yield and flea beetle infestation. Both organic acid products were applied along with 75 & 100% rates of herbicides if their use can reduce herbicide use by 25%. Control canola plots got 100% herbicide application. Results, however, do not support the hypothesis that MX-3 or VX-8 will help reducing herbicide use.
Mid season plant tissue analysis revealed that organic acids use did not change nutrient concentration in the plant foliage. Similarly, post harvest grain analysis showed no differences in
the concentration of crude protein and fats among different treatments. Organic acid products did
not influence post-harvest levels of most soil nutrients except sulfur.
Organic acids need soil moisture to enter into plant system and do necessary changes in the soil biochemistry (personal communication, Kevin Shale, Montra Crop Science). Arborg site received significantly less rainfall especially during and after seeding in the spring. The site received only 55% of normal precipitation from May 1 to September 1. This could have played a factor towards inefficacy of organic acid products in the current study. Moreover, this was the first year of study and it will be interesting to see effects in the subsequent soybean crop during 2020.
Humic compounds such as fulvic acid and humic acid are formed by chemical and microbial
degradation of plant and animal material and are a principal component of soil organic matter
(Canellas et al. 2015). In general, the application of fulvic and humic acid fertilizer amendments
have been shown to enhance root growth, increase nutrient uptake, alleviate stress, and increase yield in various crops (Canellas et al. 2015). However, studies conducted in Ontario on dry bean (Phaseolus vulgaris L.) in 2010 and 2011 using fulvic acid (LX7®, MTS Environmental Inc.) or humic acid (Plant XL®, Alpha-Agri) fertilizers showed no response. Twenty fulvic acid field trials and 15 humic acid field trials indicated that these fertilizers were ineffective, as plant
vigour, height, 100-seed weight, and yield were similar to a control treatment (Mahoney et al
2017).
Broadcast pre-plant or post-plant application of leonardite did not affect the emergence, chemical composition, or yield of wheat or canola in Manitoba (Dilk 2002). The efficiency of phosphorus (P) fertilizer was studied with and without humic acid, derived from leonardite. Application of leonardite in a P fertilizer band significantly increased the P concentration of canola tissue in the early stages of development. However, the increase in P concentration did not result in an increase in yield.
In the current study, product MX-3 did have 5% fulvic acid and it was sprayed in furrows after seeding. Additional sprays of this product were applied during early phase of the crop growth. Another granular product, VX-8 was applied with the seed.