Line 2,910: | Line 2,910: | ||
<li>Extensively researched the toxicology of the herbicides our team proposed to work with, including glyphosate, linuron and its degradative products (3,4-DCA and Acetyl-3,4-DCA). </li> | <li>Extensively researched the toxicology of the herbicides our team proposed to work with, including glyphosate, linuron and its degradative products (3,4-DCA and Acetyl-3,4-DCA). </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Toxicology Studies</strong>] | + | <p>[<strong><a href="#toxicology-studies">Toxicology Studies</a></strong>]</p> |
<ol start="2"> | <ol start="2"> | ||
<li>Researched the future use of glyphosate and linuron in Canada to ensure relevancy of our project.</li> | <li>Researched the future use of glyphosate and linuron in Canada to ensure relevancy of our project.</li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Use of Glyphosate and Linuron in Canada</strong>] | + | <p>[<strong><a href="#use-of-linuron-and-glyphosate-in-canada">Use of Glyphosate and Linuron in Canada</a></strong>]</p> |
<ol start="3"> | <ol start="3"> | ||
<li>Investigated the regulations surrounding the use of both herbicides as well as the regulations surrounding modified bacteria in the soil.</li> | <li>Investigated the regulations surrounding the use of both herbicides as well as the regulations surrounding modified bacteria in the soil.</li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Herbicide Regulations</strong>] | + | <p>[<strong><a href="#herbicide-regulations">Herbicide Regulations</a></strong>]<br> |
− | [<strong>Microbe Regulations</strong>] | + | [<strong><a href="#microbe-regulations">>Microbe Regulations</a</strong>]</p> |
<ol start="4"> | <ol start="4"> | ||
<li>Thought carefully about our project design by gathering information from local farmers who could potentially be using our project, or a similar product, in the future.</li> | <li>Thought carefully about our project design by gathering information from local farmers who could potentially be using our project, or a similar product, in the future.</li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Farmer Profiles</strong>] | + | <p>[<strong><a href="#farmer-profiles">Farmer Profiles</a></strong>]</p> |
<ol start="5"> | <ol start="5"> | ||
<li>Conducted surveys about the public’s knowledge of agricultural practices and the use of soil microbes in Canada to better understand the general public perception on matters regarding our project and its future implementation.</li> | <li>Conducted surveys about the public’s knowledge of agricultural practices and the use of soil microbes in Canada to better understand the general public perception on matters regarding our project and its future implementation.</li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Identifying Social Barriers</strong>] | + | <p>[<strong><a href="#identifying-social-barriers">Identifying Social Barriers</strong>]</p> |
<ol start="6"> | <ol start="6"> | ||
<li>Identified standards for commercialization, namely for coating the bacteria onto seeds. </li> | <li>Identified standards for commercialization, namely for coating the bacteria onto seeds. </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Microbe Regulations</strong>] | + | <p>[<strong><a href="microbe-regulations">Microbe Regulations</a></strong>]</p> |
<p>All of our research findings, interview results and surveys are carefully documented and can be found following the medal requirements overview. </p> | <p>All of our research findings, interview results and surveys are carefully documented and can be found following the medal requirements overview. </p> | ||
<h2 id="gold-medal-requirements">Gold Medal Requirements</h2> | <h2 id="gold-medal-requirements">Gold Medal Requirements</h2> | ||
Line 2,942: | Line 2,942: | ||
</li> | </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Scientist Interviews</strong>] | + | <p>[<strong><a href="#scientist-interviews">Scientist Interviews</a></strong>]<br> |
− | [<strong>Farmer Profiles</strong>] | + | [<strong><a href="#farmer-profiles">Farmer Profiles</a></strong>]<br> |
− | [<strong>System Implementation</strong>] | + | [<strong><a href="#system-implementation">System Implementation</a></strong>]</p> |
<ol start="2"> | <ol start="2"> | ||
<li>Concerns for consumer safety prompted a deeper dive into regulations on the use of linuron to ensure that the work done in the lab considered concentrations and parameters within the allowed ranges.</li> | <li>Concerns for consumer safety prompted a deeper dive into regulations on the use of linuron to ensure that the work done in the lab considered concentrations and parameters within the allowed ranges.</li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Toxicology Studies</strong>] | + | <p>[<strong><a href="#toxicology-studies">Toxicology Studies</a></strong>]</p> |
<ol start="3"> | <ol start="3"> | ||
<li>Obtained feedback from surveys and conversations with scientists, farmers, and industry professionals to continually design a project that operated within known industry and safety standards. </li> | <li>Obtained feedback from surveys and conversations with scientists, farmers, and industry professionals to continually design a project that operated within known industry and safety standards. </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Farmer Profiles</strong>] | + | <p>[<strong><a href="#farmer-profiles">Farmer Profiles</a></strong>]<br> |
− | [<strong>System Implementation</strong>] | + | [<strong><a href="#system-implementation">System Implementation</a></strong>]</p> |
<ol start="4"> | <ol start="4"> | ||
<li>When the glyphosate transformations were unsuccessful, it was decided to focus on Linuron. Refocused into the safety and regulations surrounding Linuron, both in Canada and elsewhere to better inform new experiments from a safety and implementation perspective. </li> | <li>When the glyphosate transformations were unsuccessful, it was decided to focus on Linuron. Refocused into the safety and regulations surrounding Linuron, both in Canada and elsewhere to better inform new experiments from a safety and implementation perspective. </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Herbicide Regulations</strong>] | + | <p>[<strong><a href="#herbicide-regulations">Herbicide Regulations</a></strong>]</p> |
<ol start="5"> | <ol start="5"> | ||
<li>Based on conversations with the public, farmers and scientists, identified social barriers preventing the future adoption of genetically modified systems in agriculture, and created an informative infographic to help the public learn about common practices in agriculture and provide context for our project. </li> | <li>Based on conversations with the public, farmers and scientists, identified social barriers preventing the future adoption of genetically modified systems in agriculture, and created an informative infographic to help the public learn about common practices in agriculture and provide context for our project. </li> | ||
</ol> | </ol> | ||
− | <p>[<strong>Identifying Social Barriers</strong>] | + | <p>[<strong><a href="#identifying-social-barriers">Identifying Social Barriers</a></strong>]</p> |
<hr> | <hr> | ||
<h1 id="toxicology-studies">Toxicology Studies</h1> | <h1 id="toxicology-studies">Toxicology Studies</h1> |
Revision as of 15:13, 21 October 2019
Human Practices
This year, we explored many avenues of identifying and investigating Human Practices topics surrounding our project, including safety, regulations, industry standards, end-user feedback, and effective communication. For convenience, the Human Practices work we did and how they fulfil the Silver and Gold medal criteria are summarized below. For more details regarding our work, further documentation immediately follows the summary
Silver Medal Requirements Overview:
- Extensively researched the toxicology of the herbicides our team proposed to work with, including glyphosate, linuron and its degradative products (3,4-DCA and Acetyl-3,4-DCA).
- Researched the future use of glyphosate and linuron in Canada to ensure relevancy of our project.
[Use of Glyphosate and Linuron in Canada]
- Investigated the regulations surrounding the use of both herbicides as well as the regulations surrounding modified bacteria in the soil.
[Herbicide Regulations]
[>Microbe Regulations]
- Thought carefully about our project design by gathering information from local farmers who could potentially be using our project, or a similar product, in the future.
- Conducted surveys about the public’s knowledge of agricultural practices and the use of soil microbes in Canada to better understand the general public perception on matters regarding our project and its future implementation.
- Identified standards for commercialization, namely for coating the bacteria onto seeds.
All of our research findings, interview results and surveys are carefully documented and can be found following the medal requirements overview.
Gold Medal Requirements
- Conversed with scientists from Agriculture and Agri-Food Canada, local farmers from the Waterloo region, and industry professionals to help in the design and goal of our project.
- Scientists directed us towards regulations that we needed to conform and shared what they believed were common misconceptions about the agriculture industry
- Farmers shared their experience using pesticides and fertilizers and the major factors influencing the adoption of new techniques (cost and ease of implementation), defining performance criteria for an eventual product
- Representatives from Cribit and Bayer Canada explained how seed inoculants are coated, providing us with insight on how to prepare our rhizobia for an eventual product
[Scientist Interviews]
[Farmer Profiles]
[System Implementation]
- Concerns for consumer safety prompted a deeper dive into regulations on the use of linuron to ensure that the work done in the lab considered concentrations and parameters within the allowed ranges.
- Obtained feedback from surveys and conversations with scientists, farmers, and industry professionals to continually design a project that operated within known industry and safety standards.
[Farmer Profiles]
[System Implementation]
- When the glyphosate transformations were unsuccessful, it was decided to focus on Linuron. Refocused into the safety and regulations surrounding Linuron, both in Canada and elsewhere to better inform new experiments from a safety and implementation perspective.
- Based on conversations with the public, farmers and scientists, identified social barriers preventing the future adoption of genetically modified systems in agriculture, and created an informative infographic to help the public learn about common practices in agriculture and provide context for our project.
Toxicology Studies
In our project, we worked to metabolize the pesticide linuron. We felt that it was important to complete a thorough risk assessment of the compounds linuron, 3,4-DCA, and acetyl-3,4-DCA. These molecules are created and/or consumed during the degradation of linuron. Through this analysis, we gained a deeper understanding of the hazards of these compounds, determined safe limits and exposure routes, and ultimately provided concentration targets and best practices for wet lab experimentation and implementation. The compounds were assessed along the following dimensions: Use and Environmental Exposure, Occupational Exposure and Exposure Limits, Global Persistence Potential, and Health Effects.
Linuron
Image sourced from Toxnet 1
Use and Environmental Exposure
Linuron is a urea-based herbicide that users must register in order to apply to their crops.2 It is often used in combination with other herbicides in order to control a wider variety of pests, and can be used as a broadcast or directed spray on agricultural crops, where the rate of its application can be anywhere between 0.20 to 4.50 kg a.i./ha.2
However, after re-evaluation of linuron by Health Canada’s Pest Management Regulatory Agency (PMRA) in 2012, it has been proposed to phase out the use of this herbicide in Canada due to human health and environmental risk estimations.3
Occupational Exposure and Exposure Limits
Workers using linuron or workers that are involved in the production of linuron can be exposed to this chemical through inhalation, dermal contact, and contact with the soil/vegetation that linuron is sprayed on.4 However, when used as an herbicide, toxic concentrations are variable depending on the type of crop it is being used on.4
Global Persistence Potential
In soil, linuron degrades simultaneously with other compounds and, at normal application rates, will take 3 to 4 months to degrade.2 As such, it is moderately persistent in soil, particularly clay, and therefore does not move freely.2 The more organic content there is in the soil, the lower the mobility of linuron, therefore hindering its ability to act as an herbicide.2
In water, linuron is moderately soluble and is not readily broken down.2 However, the residue from this chemical in the form of runoff results in the bioconcentration of linuron in bluegill fish and orange-red killifish.2 Based on data from Cornell’s EXTOXNET, the bioconcentration levels of linuron are referred to be low/moderate.2
Health Effects
Linuron has a Cancer Classification of Group C - Possible Human Carcinogen.1 This is due to there being no human carcinogenicity data on this chemical, with limited evidence on animal carcinogenicity.1 Studies have shown the production of benign tumours in the form of testicular hyperplasia and adenomas for male rats, as well as hepatocellular adenomas in female mice.1
In addition, human lymphocytes exposed in vitro to 1 ug/ml of linuron causes little chromosome damage.1 However, a mixture of 0.5 ug/ml linuron and 0.0005 ug/ml atrazine (another type of herbicide), showed more significant chromosomal damage.1
3,4-DCA Dichloroaniline (3,4-DCA)
Image sourced from Toxnet 1
Use and Environmental Exposure
3,4-DCA is primarily used as a chemical intermediate for dyes and pesticides.6 Environment and Climate Change Canada conducted an extensive screening process of this chemical and determined that these substances were not Toxic Substances.6 Additionally, no intentional and direct uses of 3,4-DCA were identified in Canada.6
Occupational Exposure and Exposure Limits
Exposure likely occurs via inhalation, ingestion (via drinking water) or dermal contact from the degradation of dyes and pesticides.6 Dietary exposure is very low due to the low allowable limit of said pesticides.6 Due to the limited uses of 3,4-DCCA, occupational exposure limits are not listed as exposures are very low.5 Typical exposure routes include inhalation, ingestion, and dermal contact.5
Global Persistence Potential
3,4-DCA is found to be a persistent compound in soil and water and is not expected to undergo significant degradation in these environments.5 However, the vapor phase will degrade with a 17 hour half life, limiting 3,4-DCA’s potential as a globally persistent pollutant.5 Toxicity is discussed in the Health Effects section, however, it should be noted that the compound is very toxic to aquatic life with lasting effects.5 Our project aims to lessen this effect by acetylating the compound, converting it into Acetyl-3,4-DCA.
Health Effects
Human cancer risk was not reported, and the compound was not classified by IARC, although this may be due to its limited use.5 Other health effects include severe acute dermal and oral toxicity effects and serious eye damage in animals and humans (in larger concentrations).5 Animal studies found that high exposure can cause abnormal liver or kidney function and reduces the oxygen carrying capacity of the blood with LD50 dermal contact ranging from 300-800 mg/kg.5 The compound is very toxic to aquatic life with lasting effects.5
Propanil (proxy evalutaon for Acetyl-3,4-DCA)
Image sourced from Toxnet 1
As data on Acetyl-3,4-DCA is not highly available, we studied propanil, which is another herbicide that chemically differs by having an additional methyl group on the acetyl group
Use and Environmental Exposure
Propanil is most commonly used as a pesticide.8 Possible routes of exposure for humans include consumption via trace amounts on treated crops, in addition to inhalation and dermal contact during spraying.8
Occupational Exposure and Exposure Limits
Occupational exposure routes include inhalation and dermal contact at both the facilities where propanil is produced, and the fields in which it is sprayed as a pesticide.8 There is no OEL listed for propanil in Ontario workplaces under Regulation 833.8 However, it is recommended that exposed employees be monitored for methemoglobinemia, which would indicate the requirement for an OEL at any workplace where an individual may be exposed to propanil.8
Global Persistence Potential and Ecotoxicity
Propanil is readily biodegradable with varied mobility in soil.9 It is not expected to volitize from water, and bioaccumulation in aquatic life is low. Propanil is subject to photolysis via sunlight.9 The half-life of propanil in the environment can range from 12 hours to 44.1 days, and as such propanil will not persist globally.9 Data from animal toxicity studies indicate that some amounts of propanil can be toxic to birds, mammals, and aquatic species.9
Health Effects
Propanil is not classified as a human carcinogen, but can be lethal if ingested.10 Methemoglobinemia is a common result of exposure.10 The standard treatment for propanil poisoning is methylene blue taken orally or intravenously.11
Use of Linuron and Glyphosate in Canada
Our project focuses on the use of herbicides within the realm of Canadian agricultural practices, but mainly in soybean crop cultivation. In order to do so, we narrowed down our choices of herbicide to two different contenders; linuron and glyphosate. To learn about the regulations for each of these pesticides, we emailed Robert Martin to help us find a starting point. Robert Martin is the Regulatory Information Officer at the Pest Management Regulatory Agency in Canada, and he directed us to the re-evaluation notices of both linuron and glyphosate. In order to fully comprehend his detailed response, we organized the background information on both herbicides we chose. We then added the key points from his email and the re-evaluations to guide us on where to go next.
Classification
Linuron is defined as “a substituted urea herbicide used to control annual and perennial broadleaf and grassy weeds on crop and non-crop sites”.12 Other pesticides that are substituted urea compounds have a similar mode of action and are classified as Group 7 herbicides. Group 7 herbicides are “inhibitors of photosynthesis at photosystem II, Site B. They block electron transport and the transfer of light energy.”13 At one point, linuron was a very commonly used herbicide in Canada. In 1990, 272 tonnes of linuron were sold in Canada, with 80% of it being used for fruits and vegetable crops.14 As previously stated, we are specifically observing its use in soybean crops. In these crops, engineered soybeans can metabolize essentially all of the linuron added, and respective metabolites, within 83 days.14
Glyphosate is a non-selective herbicide that will kill most plants by preventing them from making essential proteins needed for growth.15 Glyphosate is classified as a Group 9 herbicide. Group 9 herbicides are amino acid derivatives that inhibit 5-enolpyruvyl-shikimimate-3-phosphate synthase (EPSP synthase). Glyphosate is the main ingredient in the commonly known herbicide, Roundup, and it is the most commonly used herbicide in Canada.16 Glyphosate is also the world’s most commonly used herbicide.17 Part of the reason we chose glyphosate as a potential herbicide of interest is due to its prevalence in Canadian and Global agriculture.
For a full review on the toxicity of both linuron and glyphosate, please refer to our [Toxicology Studies](Linkto: Toxicology Studies).
We faced two problems with our choices of herbicide.
- Glyphosate is currently under study for accusations on its carcinogenicity, and the adverse health risks for humans. It was subject to various re-assessments from the International Agency for Research on Cancer (IARC)
- Linuron is slated for re-evaluation; the proposal insisted that linuron be phased out entirely 17
Health Concerns and Review of Linuron and Glyphosate
In 2017, Health Canada published their final re-evaluation stating that glyphosate is not genotoxic and is unlikely to pose a human cancer risk.18 They also stated that the occupational and residential risks associated with its use are not of concern, if label directions are followed accurately. Health Canada faced several (8) notices of objection on this decision, which is most likely due to comments made on the “carcinogenic effects” it has on humans. In a statement made in January 2019, Health Canada stands by its decision because the objections were not scientifically supported.19 “No pesticide regulatory authority in the world currently considers glyphosate to be a cancer risk to humans at the levels at which humans are currently exposed.”19
Linuron, on the other hand, remains a concern. In February 2012, a proposed re-evaluation was published by Health Canada stating their intention of removing linuron from the Canadian market entirely because “under the current conditions of use, the human health and environmental risks estimated for linuron do not meet current standards”.20 Health Canada wants to conclude that the best course of action was to get rid of linuron, however the final decision has yet to be made.20 This decision is set to be published in February 2020.
Conclusions
Completely ridding of linuron does not help our project. However, if we could successfully prove our hypothesis through the introduction of genes for linuron metabolism in Bradyrhizobia, our project could act as a precedent for other potential ventures focussed on herbicide metabolism in similar microorganisms by introducing transgenes.
Scientist Interviews
While developing our project, we wanted to consult research experts in the field to better understand the regulations that guide their work, as well as their experience interacting with the general public regarding the controversy in agriculture. We were fortunate to have been able to correspond with two research scientists at Agriculture and Agri-Food Canada to talk about their experience on these matters. The following sections summarize our findings from our conversations with Dr. Breanne Tidemann an Dr. Sara Martin.
Dr. Breanne Tidemann, Research Scientist (Field Agronomy, Weed Science)
Individuals in the agriculture community, both in research and industry understand the reasons for herbicide use. The general public needs help understanding why herbicides are important. This can be achieved through comparisons and analogies, such as comparing large-scale farming to gardening. Weeding gardens in homes by hand to keep flower beds healthy is feasible. Weeding a farmland that is thousands of times bigger than a common flower bed and contains that many weeds by hand is no longer a feasible way of dealing with weeds choking out desired plants. Furthermore, hand weeding is not a fun job; finding labour workers for it would be difficult and not economically feasible for the land owners.
The general public has an aversion to products that have had pesticides or herbicides used on them, but they do not recognize that something being labelled “organic” does not necessarily mean “pesticide free.” Organic farming uses a different set of accepted pesticides, such as vinegar (acetic acid) or iron products. Currently organic farms produce far lower yields with their methods and are therefore infeasible to be the only methodology used for food production on a national and global scale.
Dr. Sara Martin, Research Scientist (Plant Systematics, Weeds and Invasive Species)
Members of the general public tend to have a negative view of herbicides and feel strongly that farmers should stop using them. However, farmers do not share this same view, as the herbicides that are currently being used in a widespread manner are being used for good reason. Often, the chemicals that could replace herbicide use are far worse for people and the environment. The agriculture industry, like all others, requires a workforce and without herbicides the labour of hand-weeding falls on a very vulnerable group of people. Weeding cannot be avoided, and they have to be removed in order to maintain ideal crop quality and yield. Historically, without herbicides the labour associated with weeding fell on women and children within the communities. Many people understand that this is historically what occurred in first world countries, but many don’t realize that this is actively occurring in third world countries. This is both economically inefficient and hard, potentially dangerous labour.
Regarding federal and provincial regulations, it was suggested to look into the Pest Management Regulatory Agency to gain insight on pesticide regulations.
Next Steps
Both Dr. Tidemann and Dr. Martin feel that integrated weed management is the key moving forwards within the agricultural industry. The integrated weed management strategy requires the use of chemical, physical, biological, and cultural controls to manage weeds. This strategy only works when all these factors are effectively combined, not when any of them work alone. This strategy which takes into account aspects such as tillage, narrow row spacing, and using diverse crop rotation would help farmers develop competitive crops without relying solely on herbicide and pesticide use. The strategy of integrated weed management is one that could easily include our altered rhizobia to aid with crop quality maintenance and yield rates. Furthermore, Dr. Martin’s suggestion to explore the Pest Management Regulatory Agency guided our investigation outlined in the following sections.
Herbicide Regulations
Before proceeding further, we had to determine whether or not the work we were doing was permitted under restrictions set by the provincial government. We emailed both the Minister and Deputy Minister of Agriculture, Food and Rural Affairs to ensure that our research project complied with provincial policies.
The Ontario Ministry of the Environment, Conservation and Parks administers the Pesticide Act and Regulation 63/09, which is responsible for managing the sale, use, transportation, storage and disposal of pesticides in Ontario.21,22 Since we were applying glyphosate and linuron to our trials, we had to make sure we were working appropriately under the exemptions for the use of these pesticides for scientific purposes.
The linuron we are using falls under Class 4 of Regulation 63/09.23,24 Section 9 of Regulation 63/09 outlines the pesticides that are prohibited; it states that registered pesticides under class 4 are not part of the group of prohibited pesticides.22 In a similar manner, the glyphosate we are using falls under Class 7 of Regulation 63/09 and is not part of the group of prohibited pesticides as outlined by Section 9, as well.22,23,25
Image sourced from Environment and Energy Ontario.23
Image sourced from Environment and Energy Ontario.24
Image sourced from Environment and Energy Ontario.23
Image sourced from Environment and Energy Ontario.25
Image sourced from Environment and Energy Ontario.25
Microbe Regulation
Image sourced from Grist
Part of our project was to understand whether or not a genetically altered organism could be realistically applied and used in Canadian agriculture. To assess whether we could realistically expect our product to be used for agricultural purposes, we corresponded with the office of the Ontario Minister of Agriculture, Food and Rural Affairs. Our altered Rhizobia falls under national pesticide regulations, specifically under the regulations set in place by the Pest Management Regulatory Agency. The regulatory directive Guidelines for the Registration of Microbial Pest Control Agents and Products provides a set of guidelines that encompass important factors.26 These factors include biological properties, potential pathogenicity, ability to multiply, and determine whether or not a microbial agent is safe to use and is of value for agricultural practices. Under this directive, microbial pest control agents are defined as “naturally occurring or genetically modified microorganisms, including bacteria, algae, fungi, protozoa, viruses, mycoplasmae or rickettsiae, and related organisms”, meaning that our genetically altered Rhizobia fall under these regulations.26
This regulatory directive was developed in part to be able to support “effective and sustainable pest management and the introduction of new pest management technology” and seeing as our Rhizobia could become a big part of integrated weed management strategies, registering our methods and turning them into legitimate regulated methods is the next step.26
Registering our Rhizobia would require submitting notable amounts of information to the Pest Management Regulatory Agency but much of this information has already been gathered by different members of our iGEM team. Information such as Construction of the Recombinant Microorganism, Nature and Expression of Introduced or Modified Genetic Material, Environmental Toxicology, and others. (INSERT HYPERLINKS HERE)
As stated in the directive, not all microorganisms require the same type of information to be submitted to the Pest Management Regulatory Agency. Further work in the following areas would need to be done for the successful registration and implementation of our altered Rhizobia:
- Manufacturing Methods and Quality Assurance
- Potency Estimation and Product Guarantee
- Storage Stability Testing
- Food and Feed Residue Studies
- Laboratory Studies on Environmental Fate
- Pure Culture Testing
- Microcosm Testing
- Value Assessment
- Performance Assessment
- Laboratory and Growth Chamber Studies
- Compatibility with Crop Protection and Management Strategies
Conclusions
Many of the data that needs to be gathered for successful registration and use of our product requires equipment, space and time beyond the scope of our project. We strongly believe that if we had all of this data gathered, our altered Rhizobia would have a strong chance of being accepted and becoming an integral part of integrated weed management strategies in Canadian agriculture.
Farmer Profiles
To help our lab team design and implement our project we spoke with local farmers to better understand their thoughts on genetically modified Rhizobia, and how it would impact their farming practices. A long term goal of our project is to have a product for farmers that is easy to use, understand, and work with. To assess how this could be achieved we focused our questions on getting to know our local farmers personally (how long have they been practicing, what do they farm, what techniques do they currently use, etc.) as well what key factors they look for when considering a new product and whether or not to implement it into their practices.
Karl Gmach
Gmach Gardens
Starting his farm in 1934 in the rural areas of the Waterloo Region, Karl from Gmach Gardens is a seasoned grower with an abundance of farming experience. As a traditional grower, Karl is a strong proponent of natural and holistic farming. He prides his farm on supplying consumers GMO-free produce. Additionally, Karl only uses as much pesticide as needed each season and favours organic fertilizers (such as manure) over commercially available products. However, fertilizer can be expensive ($500 per acre of land) and Karl tries to utilize alternative farming practices, such as manual removal of weeds as a pest control method, whenever possible.
Karl told us that although he does not know a lot about genetically engineered bacteria and their effects, he is more than willing to implement modified Rhizobia into his farming practice and use less fertilizer.
Karl is aware that his customers are often hesitant to products labelled ‘GMO’, so before implementing modified Rhizobia into his farms he would want to ensure it is cheap, safe, effective, and easy to implement into his current practices.
Highlights
Interested in using modified Rhizobia but only if it is cheap, safe and easy to implement. Concerned about how consumers will feel towards modified soil bacteria and growing conditions.
Steven Fekete
Fekete Farms
Fekete Farms is a 3rd generation family-run farm by brother-sister pair, Steven and Carolyn Fekete local to the Region of Waterloo. Steven told us that he uses pesticides every 2-3 weeks along with fumigating the soil for nematodes once every year. Each season, Steven gets the nutrients in his soil analyzed by the Canadian Department of Agriculture and Agri-Food to determine the volume and variety of fertilizer he should use. However, he highlighted to us that he only uses the minimum amount of fertilizer required due to its expensive price tag. Steven has a strong understanding of the microbial environment in the soil as well as the technological advances in genetic engineering technology, specifically seeds inoculated with genetically modified bacteria. Steven told us that he understands using modified bacteria would save his practice money, but has concerns that his consumers will not respond well to ‘bacterially enhanced’ produce due to a lack of education on what genetic engineering really is. Steven often receives questions from his customers about how safe GMOs are and though he would like to use less fertilizer, he wants to make sure his sales will not be negatively impacted.
Highlights
A strong supporter of modified Rhizobia and modified Rhizobia-based products. Concerned how consumers will feel towards ‘bacterially enhanced’ produce.
System Implementation
Background
To better understand how our genetically modified rhizobia could be used in industry, we did some online research and also reached out to Phil Nadalin of Beyer Canada, a company that regularly deals with the distribution process of inoculated seeds. This allowed us to better understand how our project could be implemented in the current market, and helped us to identify new avenues for improvement.
Current Process
Inoculation is defined as “the process of introducing Rhizobium bacteria into the soil in close proximity to the seed” so that the Rhizobia can infect the root hairs and fixate nitrogen for the developing seedling.27 Seeds are either pre-inoculated (during late winter - early spring) or have the rhizobia applied in the field (as a peat, liquid, or granular based product) in the furrow with the seeds.
Pre-inoculation
For the pre-inoculated process, seeds are inoculated while being treated with fungicides and insecticides during the previous fall, winter, or early spring. This is done with a “peat-based inoculant encapsulated with a seed coating” using commercial seed treaters such as the drum treater shown in figure 1.
A drum treater (Image from Ag Solutions Group28)
The treated seeds can then be stored in bagged units or totes during the winter, or transferred directly to gravity wagons for farmers usage. The seeds need to remain out of the sun and should be kept cool and dry with minimal temperature fluctuation.
Application in the field
To be applied in the field, the rhizobium bacteria will be contained within a peat, liquid, or granular based product. All of these products should be placed in the seedrow or in a sideband (approximately one inch below and one inch to the side of the seed) so that the rhizobia can quickly come in contact with the developing seedlings. The rhizobia should be applied using a tank and meter that is separate from any fertilizer.
Common Practices
Rhizobia is often used with Penicillium bilaiae, which is “a fungus that solubilizes phosphate to make it more available for plant uptake.'' It is also used with Lipo-chitin oligosaccharides (LCOs), which are a “type of additive found in select products. The nodulation process starts with the pulse root secreting flavonoids, which are sensed by the rhizobia. In response, the rhizobia produce their own signal (Nod factor) back to the plant, and the plant responds by allowing the root hair to be infected by the rhizobia. These Nod factors are often called LCOs, and can be included in some inoculants.” 27
For harsh conditions, granular products are usually preferred over other methods. This is particularly true when soil moisture conditions are below normal.
How This Relates To Our Project
Assuming that our modified rhizobia are as durable as the natural rhizobia, there should be no issue in the technical feasibility of implementing our rhizobia using the standard inoculation procedure. Potential issues would lie mostly in regulations around this process, as well as stigma and a lack of market demand. For example, if the genetically modified rhizobia need to be kept separate from standard rhizobia then we would need a seperate tank and pumping system to accommodate that. We have also learned that inoculated seeds would need to be kept cool and dry during storage to help with the effectiveness of the product. Additionally, future testing could be done with various fungicides and insecticides as well as with Penicillium bilaiae and LCOs to ensure the compatibility of our modified rhizobia with the inoculation process.
Identifying Social Barriers
Despite the benefits of using and implementing genetically enhanced systems in agriculture (whether the plants themselves are being modified or through the use of microbial inoculants), there exists significant social barriers that hinder their adoption.29 As such, in order for our system to be adopted in the future, we needed to better understand these barriers and explore methods to address them.
Surveying the General Public
To gauge the knowledge and awareness of the public, we performed three surveys over the course of the year. The first survey was conducted at this year’s Waterloo-Wellington Science and Engineering Fair (WWSEF); a STEM fair composed of middle school participants (grades seven and eight) by majority. This survey was conducted to assess how middle school students interested in science and engineering viewed our project. Some of the results are depicted below.
Overall, the WWSEF participants had split views on GMOs, had negative views on pesticides and/or herbicides, and did not know enough about adding microbes to soil nor nitrogen-enriched fertilizers to form an opinion.
The second survey performed was through Waterloo iGEM’s social media accounts (Instagram and Facebook) where our following is comprised primarily of secondary and post-secondary students. Similar to the WWSEF survey, this survey was conducted to assess how both levels of education mentioned viewed our project but also to see if an increase in years of education changed their awareness in regards to crucial aspects of our work (GMOs, herbicides, fertilizers, etc.).
Similar to the WWSEF students, secondary and post-secondary students surveyed were split over the use of GMOs but with a larger skew towards positive, had negative views on pesticides, and did not know enough about nitrogen-enriched fertilizers to form an opinion. Unlike in WWSEF survey, the social media survey showed a positive majority regarding adding microbes to soil to help with plant growth.
The final survey was performed twice with our group of SHAD students this year. For more information on the SHAD workshop, please refer to segment written about SHAD on the Engagement and Education page. Both the workshop hosted and the survey itself were designed to test if dedicating time to teaching individuals about what GMOs are, how farming practices are currently ran, and what our project aims to do would change their view on our work. To test this, we had the SHAD students take the survey at the beginning of our workshop and then again at the end in order to test how further, project-specific education would change their opinions.
The SHAD students opinions on GMOs initially reflected that of the other surveys with split results from positive to not knowing enough to form an opinion. After the workshop, the vast majority of the students were in support of GMOs and those that were not were neutral towards them. Pesticides and adding microbes to the soil showed similar trends with the students initially being split evenly between not support them-not knowing enough to form an opinion and supporting them-not knowing enough to form an opinion, respectively. After the workshop, the students were in support of both the use of pesticides and adding microbes to the soil to help plant growth. Finally, the students moved their opinions from majority neutral in regards to the use of nitrogen-enriched fertilizers to negative-neutral.
For all data used in the above three surveys, click here!
Farmers and Scientists
To gather more information about some of the social barriers preventing the adoption of systems such as our project, we referred to our conversations with farmers Karl Gmach and Steven Fekete, and scientists Dr. Sara Martin and Breanne Tidemann.
Conclusions
From the survey and our conversations, we were able to gain insight on some of the barriers that the agriculture industry faces preventing the implementation of systems using GMOs. After compiling and analyzing the results, we were able to draw eight major conclusions that span locally in Waterloo, provincially across Ontario, and nationally across Canada. Note: our survey consisted of 205 responses and this sample population is referred to as “the public” below.
- Majority of the public have a negative perception towards the use of herbicides.
- The public is split between positive, negative, and neutral stances on the use of GMOs.
- Majority of the public claim to not know enough about the use of nitrogen-enriched fertilizers in agriculture to form an opinion.
- While 44% of the public were in favour of adding microbes to soil to assist plant growth, 40% of the public felt negatively or didn’t know enough about the topic to form an opinion.
- Majority of the public is unfamiliar with the concept of synthetic biology
- Researchers observed that there is a strong misconception on definition of “organic”.
- Farmers are not extensively familiar with the impact of rhizobia or other microbes in soil.
- Many farmers understand the benefits of GMOs and would be interested in using them, but choose not to due to public perception.
These conclusions helped us better understand the public’s perceptions of agricultural practices and how they influence what techniques farmers will employ. Overall, there is a highly negative view towards the use of pesticides and GMOs, which likely originates from their portrayal in the media as well as a lack of awareness on the countless benefits they provide. When it comes to the techniques that farmers choose to use in their fields, we discovered that many of their decisions are highly contingent on the public’s perception of the method. Thus, they are slow to adopt processes that use GMOs in fear of losing business due to negative reception.
Particularly regarding our system, we realized that not all farmers are extensively knowledgeable of the rhizosphere and the benefits that are brought by the microbial community. A lack of awareness from a farmer’s point of view poses a barrier as they would require more information before considering the use of our system.
Addressing Social Barriers
As mentioned in the previous section, our goal was to identify some of the social barriers that would prevent the adoption of our system and genetically modified techniques in general. Based on the eight conclusions derived earlier, we wanted to create an infographic that addresses some of the common misconceptions and serve as an educational tool to those who may be unfamiliar with the rhizosphere and the role they play in promoting plant growth. The following infographic was shared on our social media platforms and is viewable by scanning the QR code underneath.
QR Code
References
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Pictures:
https://grist.files.wordpress.com/2014/06/microbes.jpg
https://agsolutionsgroup.com/equipment/seed-treating/seed-treaters/lpx2000/