Team:WashU StLouis/St Louis
Monsanto’s industrial seed chipper
Roots from plants whose seeds were treated with external coating
Working towards our goal to explore and learn more about unconventional farming methods in St. Louis, we visited SLIP, a, indoor hydroponics farm, on July 20th. Their farming methods solely uses water and nutrients to grow plants without soil, reducing transportation and water needs, as well the need for arable land and providing a new use for abandoned buildings. We first toured their facility to see how the plants are grown. They use vertical growing modules made from PVC towers to minimize space and use the nutrient film technique to cycle water and nutrients through. Some of their crops are grown exposed to natural sunlight with large window panes and others are grown in the basement with custom LED bulbs that emit limited wavelengths of light to optimize growth for each specific type of plant. These methods maximize plant yield and freshness and minimize growth time.
We spoke to Venkat Papolu, the founder of SLIP and developer of most of their infrastructure and equipment about the goal of the company and advantages and disadvantages of hydroponics. They aim to bring fresh and organic produce to food desert communities year-round. From their small facility downtown, their aim to expand to a large-scale warehouse to increase crop yields.
He also brought up many common advantages and drawbacks of novel agricultural technologies. Indoor hydroponics allows for a highly controlled environment, so the plants will be purely pesticide-free and can be grown year-round. There are no disadvantages due to the lack of soil because the proper nutrients are all delivered through water. However, although hydroponics is cheaper than conventional agriculture at scale, the higher startup costs increases the initial prices of their products, making it hard for the local community to purchase the goods. While high-income communities love to purchase the food and are willing to pay more for it, this prevents it from going to those who need fresh food the most. In addition, indoor agriculture lacks some of the benefits of outdoor agriculture. All pollination must be artificial, a time-consuming process. Most indoor plants do not receive natural light, so artificial lights must be installed, which are expensive and energy-intensive. However, the growth in use and scale of these technologies will allow for these drawbacks to be minimized, such as through the use of renewable energy and decreasing costs per unit.
We toured the Danforth Plant Science Center on July 24th and were able to visit numerous labs and learn more about individual projects. After corresponding with Dr. Bart over email, visited the Bart Lab in detail and saw the plant death room where their experiments are carried out after the plants are grown in the greenhouses. While visiting the greenhouses, we learned about the growth process of cassava, which is used for research purposes by the Bart Lab. The greenhouse facility houses their Conviron phenotyping machine. We saw the process happening as each plant was barcode-scanned and imaged to collect valuable information for fast and reliable phenotyping. We also saw a model of a larger scale image-based phenotyping technology used in farms in Arizona.
After visiting the research wing of the center, we saw the education and community outreach area where they hold many events year-round for all members of the community to learn more about biotechnology and research methods.
We then sat down with members of the Bart lab to speak with them about their research with resistance genes. The students we spoke with studied cassava bacterial blight and cassava mosaic virus. They discussed the resistance genes and plant-effector interactions they studied, as well as interactions between the resistance genes we studied In addition, they explained how genomes are screened to discover new resistance genes. We also discussed disease management and methods of durable resistance in cassava and compared this to management of wheat rust fungi.
On June 21st, our team was able to tour Pfizer’s facility to learn about their synthetic drug manufacturing process. Many of their drug compounds are synthesized using E. coli and yeast and are produced in large quantities. To ensure top quality, they conduct their drug manufacturing in a separate building with increased safety measures. The building contains numerous bioreactors of various sizes for different stages of production.
We visited numerous labs, all working with synthetic biology and were able to see the incredibly large amount of bioreactors being used, as well as the microbioreactors that were a fraction of the size of traditional ones. A couple scientists in each lab explained to us the work they were doing from R&D to testing the synthesized compounds to material purification.
Several of our team members met with Dr. Kunkel, who researches virulence in the model plant-pathogen system of Arabidopsis thaliana and Pseudomonas syringae at Washington University. During the meeting, she spoke about the methods of plant-pathogen interaction in A. thailiana and P. syringae, and compared them to interactions that occur between wheat and wheat rust fungi. She gave the example of an effector AvrRpt2, a protease that is injected into cells by type three secretion system, which interferes with the plant’s production of and response to auxin, a plant hormone and does not necessarily cause a hypersensitive response. She also discussed how new effectors are found and methods of interaction are investigated. While P. syringae is a weak pathogen that is rarely an agricultural issue, this system is a very good model for more complex systems that allows other researchers to understand what patterns to look for in more complicated systems.
Our team met with Dr. Shah, a researcher at the Danforth Plant Sciences Center who studies plant defensin proteins, another method of innate plant resistance to fungal pathogens. He compared resistance and defensin proteins, noted the benefits and drawbacks, and discussed how both are being studied as methods of providing durable resistance to pathogen infection. In contrast to resistance proteins, defensin proteins actively attack the fungal pathogen. For instance, some target and damage the plasma membrane of the fungus. Also, one defensin gene can provide broad spectrum resistance to a variety of pathogens and strains, unlike resistance genes, which are typically pathogen-specific, and in some cases, strain-specific. However, in order to provide durable resistance, one or more defensin genes are often combined with resistance genes to reduce the possibility that a pathogen can develop resistance. Defensin proteins have been shown to protect against leaf rust, but have not yet been tested with stem rust.
Prior to our meeting with Dr. Shah, our team had intended to use a polystyrene membrane for our spore trap based on what we had previously read in literature. However, Dr. Shah informed us that any hydrophobic material could be used as a spore trap, so we decided to change the material of our membrane to polyethylene with a lower environmental impact.