Tag Archives: Agriculture

Pip, SAR, and GMOs: How UBC Researchers are Advancing our Knowledge of Plant Immune Systems

What would happen if plants couldn’t protect themselves? Well, for one, they would be prone to many different infections and viruses. Ultimately, plants would die without the ability to protect themselves. To really put things into perspective, humans would not have many of the food sources they have without plants.

Yuli Ding, a 5th year PhD student at the University of British Columbia, and her colleagues made a coincidental, break-through discovery in October 2016. Focusing on the ability of plants to resist diseases that they’ve previously encountered, called Systemic Acquired Resistance (SAR), Ding set out to determine if a specific molecule is required for this type of protection. SAR is described with greater depth in the following podcast with the researcher herself. The molecule in question was Pipecolic Acid (Pip). According to the findings of the scientists, “Pipecolic acid could be a relatively important mobile signal is the systemic acquired resistance.” In simpler terms, Pip aids in SAR by activating the process.

We had the opportunity to interview Yuli Ding about her research to help clarify some of these complex concepts. Listen to her explanations of the research in the following podcast.

What happens to plants that cannot complete SAR? Mutated plants, with a non-functional SARD4 gene, are SAR-deficient and thus unable to effectively defend against diseases. Instead of making Pip to activate SAR, a Pip pre-cursor molecule gathers in the plants – demonstrating SARD4’s importance in synthesizing Pip. Since Pip is not being created, the plants don’t exhibit SAR and are less able to defend themselves when infected by pathogens.

In this video, Yuli Ding describes how they identified SAR-deficient Arabidopsis plants, and demonstrates one of the main lab techniques, Polymerase Chain Reaction, that her team used to help identify Pip as a signal molecule.

Arabidopsis Timelapse
Music: Horizon, by Letmeknowyouanatole

Why should we care? SAR is a key process by which plants protect themselves, so SAR is an essential mechanism in ensuring the maintenance of agriculture and healthy crop yields.

Science is advancing at a rapid rate and the use of Genetically Modified Organisms (GMOs) has been increasing. A GMO is the result of a gene transfer between organisms. For example, the gene of one organism is inserted into another organism in order to improve that organism. The results of this study could be a stepping stone to creating GMOs that have better SAR, and are better able to defend against disease. Specifically, the genes responsible for synthesizing Pip could be added to immuno-compromised organisms. Genetic modification could also be used to make plants have stronger SAR or better immune systems.  Although the use of GMOs could be beneficial, GMOs pose several threats to the environment and other organisms.

What can we do with this research right now? The findings of this study could help improve the yield of crops and the number of successful crops. Farmers and agriculturalists could now focus on improving the environmental conditions of their plants to ensure that all requirements for a plant to be healthy are met. A healthy plant would increase the chances of proper SAR. All in all, a healthy plant is a happy plant!

 

By Navpreet Ganda, Pavneet Virk, and Zhongkai He.

The Solution is Sugar!

The farming industry requires an immense amount of labor and money. However, there are many factors that come into play when producing a healthy crop. Focusing on rice agriculture, examples of harmful disease that cause loss of crops are blast and brown spot.

Blast disease is the most important disease that has been affecting rice crops worldwide. This disease infects rice crops by creating lesions on different parts of the plant, such as the leaves, seeds and even roots. The lesions lead to cell death and eventually cause death of the leaves and entire plants. The following video demonstrates the impact of the rice blast disease.

Credit: This Week in Louisiana Agriculture, YouTube.

So, what is being done to protect crops?

Since rice crops are a predominant food source for a vast population around the world, it is important to keep these crops healthy. One method of controlling disease in rice crops are fungicides, however, they sometimes have negative effects on the environment and human health. For example, the fungicide Mancozeb creates concerns in human metabolism and respiration.

Fungicides are not a long-term solution! Pathogens are able to become resistant to fungicides overtime and infect crops. The production and use of fungicides is costly and to have them become ineffective is a waste of both time and money. Due to these effects, research is being conducted in order to find substitutes for fungicides.

What have researchers found?

One solution is sugar! Chitosan specifically, is a sugar that can be found naturally in the shells of crustaceans and is renewable.

Could Chitosan be the solution to the long-lasting issue of using fungicides in agriculture?  The most important benefit of Chitosan is that it is naturally present in the environment and therefore is not as harmful as using chemicals. Secondly, Chitosan is abundant, accessible and not nearly as expensive as producing chemical fungicides — which are only short-term solutions.

How does Chitosan work?

Chitosan possesses properties that help protect plants and promote antifungal behaviour. A study proposed that Chitosan inhibits the access of fungi to essential nutrients of plants, preventing the growth of fungi.

Another study concluded that Chitosan modifies the outer membrane of pathogens, destroying their ability to attack plants and therefore making crops less susceptible to fungal virus and disease. Along with preventing fungal disease, Chitosan also activates defense mechanisms in plants. The dual action of Chitosan makes it an ideal substitute for fungicides.

Is Chitosan a long term solution?

I believe that the Chitosan solution definitely has benefits such as, being renewable and inexpensive but it should be tested extensively to prove success. Research has shown several qualities of Chitosan such as antimicrobial properties against viruses, bacteria, fungi and insects, which further confirm it as a good solution for protecting rice crops. Despite these findings, Chitosan should be tested thoroughly before being put into practice to avoid putting crops at risk of failure.

Pavneet Virk