Plant cancer leads a double life as a tailor

by Allison Younkins

“Corn Smut” is both a plant cancer and a tailor.  This maize fungus does not tailor clothes but it does tailor its genes to attack the host tissue it is infecting.  This April, researchers and Stanford unlocked some astonishing secrets about how corn smut manipulates genes in its genome to affect its host more severely.

The researchers used laboratory techniques such as DNA microarrays, which allowed them to seem which genes in the pathogen’s genome were activated.  What they found will inevitably change the way pathologist’s study plant pathogens and human cancers.  Their experiment showed that the pathogen had different active genes when it was infecting various parts of the plant including the seedlings or the adult leaves.  About 30% of the pathogen’s genome was activated no matter where the infection was located.  The activation of the remaining 70% varied depending on the location of the infection.  This phenomenon has been overlooked in the past because normally only tissues from one cell type are studied in an experiment.

These findings may allow scientists to return to pathogens retroactively and discover new information about the mechanism of plant diseases including corn smut.

This is a significant finding for the plan pathology community but it also has implications for human disorders.  Corn smut is a tumor-causing plant cancer, and researchers believe that information from this study could fuel new experiments in cancer research.  Their discoveries about this plant cancer suggest that diseases such as cancer can alter their genetic material to better infect a host.  If the activated genes can be targeted, this could create more specific treatments and medications for cancer.

Corn smut has traditionally been overlooked as a research interest because it does not devastate maize crops and is not harmful to humans who eat infected maize.  It is common in Mexico for the plant tumors to be used in food and can even be grown intentionally.  However, this seemingly unimportant pathogen may hold a wealth of information about how diseases attack their hosts and what we can do to stop them.

A maize tassel infected with corn smut. The tumors are the large white, bulbous growths, some of which have turned yellow or brown. Linda A. Cicero, Stanford University News Service

Want to hear a Stanford University researcher speak about her research on corn smut? Check out the link below

Plant Pathogen Tailors Attacks Genetically

Dehydrins may quench the thirst of plants affected by drought

The last time you were thirsty, you probably opened your fridge for an ice cold Pepsi or even filled up your water glass from the sink.  This seems like a simple task, but to a plant this can be a life or death situation.  Drought affects areas in our own country as well as countries abroad.  Southern China is currently experiencing their worst drought in almost 100 years.  One rural farmer comments that in years past he has sold his wheat crop for $585 and this year it is only worth $30.

In a collaborative effort between Villanova and Drexel universities, researchers are beginning to discover a new way to combat this problem. Published in the American Journal of Botany in March 2010, their research began with a plant called the “resurrection fern” (Polypodium polypodioides) which can lose 95% of its water content without experiencing cell death.  One of the main scientists from Villanova explains that this is truly a miraculous property.  He says, “Imagine this happening to a human.  Most of us wouldn’t make it past 10% or 20%.”  Similarly, most common agricultural crops cannot survive water loss of 20-30%.

They used research techniques such as western blotting, immunolocalization, and atomic force microscopy to identify proteins that help the resurrection fern survive in extreme drought condition.

A class of proteins called dehydrin has been previously identified to participate in this miraculous drought resistance.  However, this study was able to identify the location of dehydrin proteins during the process of dehydration.  They found that the proteins were “prevalent” in the plant’s cell wall.  This is an important discovery that may lead to new findings about the mechanism of this reaction.

Information about this protein class has positive implications for common agricultural plants that currently don’t have protection against drought.  Dehydrins, and the mechanism of their role in drought resistance, could be the answer for thirsty plants worldwide as research continues.

Want to learn more? Check out the resources I used for this blog:

Fluorescent supermarket lighting leaves spinach more nutritious than ever

Spinach on display under 24-hour light in supermarkets actually gains in content of some nutrients. (Marc Villalobos, USDA-ARS)

by Allison Younkins

Healthier spinach, just add light

Spinach, or Spinacia oleracea, is one of the most nutritious vegetables found in the grocery store.  Normally packaged in a clear plastic container, most spinach leaves are exposed to fluorescent supermarket lights for up to 24 hours a day.  Surprisingly, a study published in March in the Journal of Agricultural and Food Chemistry shows that the light exposure boosts the vegetable’s nutritional content to astonishing levels.  Scientists at the Kika de la Garza Subtropical Agricultural Research Center and the Atlantic Food and Horticulture Research Centre conducted an experiment to test the affect of lighting on the nutritional value of spinach.  They exposed spinach to either continuous light or darkness while under simulated supermarket storage conditions for up to 9 days.  Even spinach leaves exposed to the fluorescent lighting for only three days showed significant increases in important vitamins and antioxidants.  The leaves exposed to nine days of light had increased folate levels by 84-100% and levels of vitamin K between 50-100%.  Even further, the group exposed to no light had declining nutritional values.

How light contributes to nutrition: the connection

The main researcher on this project, Gene Lester of the USDA Agricultural Research Service, explains how supermarket lighting can contribute to vitamin and mineral levels within the leaves of this powerhouse plant.  Lester clarifies that although a leaf has been detached from the original plant, it can still undergo the process of photosynthesis.  The lighting in supermarkets allows the spinach leaves to continue creating vitamins and minerals as they would naturally.  Lester comments, “As long as there is moisture in the leaves and as long as there is gas exchange and light, it is good to go whether they are picked or not.”

How other vegetables and consumers can benefit from this study

The most exciting implication of these results is that other vegetables may receive the same benefits from fluorescent lighting.  Keeping vegetables fresh in grocery stores is a constant struggle, and additional studies may illuminate more effective storage solutions.  One serving of spinach currently provides 20% of your daily recommendation for vitamins C, A, B9, K, and E but with further research soon you may be getting more bang for your nutritional buck!

Want to learn more? Check out the resources I used for this blog:

Supermarket lighting enhances nutrient level of fresh spinach

Want fresh veggies? Let there be light!

Fungus to the rescue

by Allison Younkins

How one fungus is changing the way we battle pests

The fungus Muscodor albus rarely gets to play the hero-but that could all be changing according to USDA Agricultural Research Service (ARS) scientists.   In February 2010, results from an ARS study regarding the effects of this fungus on a common wheat disease were published in The Canadian Journal of Microbiology. Throughout multiple experiments in recent years, researchers have found that Muscodor albus was effective in eliminating common insect and fungus pests that attack wheat, apples, and grapes.

The super powers of Muscodor albus

This natural fungus could be the answer to eradicating numerous agricultural pests.  But how does this fungus do it?  Instead of physical strength, or even the ability to fly like other superheroes, this fungus emits Volatile Organic Compounds (VOCs) that are known to naturally kill pests and other fungi.   The most recent Muscodor experiment tested the fungus’ ability to eliminate another fungus T. tritici, which reduces wheat yield and lowers crop quality.  In laboratory experiments, the VOCs from Muscador killed 100% of the T. tritici spores and prevented the spread of the fungus.  This is just one of numerous experiments regarding Muscodor albus-results show that this fungus is also effective against agricultural villains like potato tuber moths, apple codling moths, and the fungus Botrytis cinerea.

from "Fungal Fumes Clear Out Crop Pests" in the February 2010 issue of Agrictultural Research magazine. Blair Goates, plant pathologist, examines wheat seed after applying a formulation of the biocontrol fungus Muscodor albus, shown in the foreground.

This biocontrol may be the answer for growers and consumers: how fungus is actually better for you

Fungi such as T. tritici are currently controlled in the field by chemical pesticides, which are effective-for now.  Researchers are interested in biocontrol solutions because it is possible that these agricultural scoundrels will become resistant to the chemical pesticides.  This could expose growers to tremendous financial losses because they have “become reliant” on chemical solutions, according to plant pathologist Blair J. Goates, with the ARS Small Grains and Potato Germplasm Research Unit.  And while chemical effects on humans and the environment are a constant concern with chemical pesticides, the use of Muscodor albus does not harm humans or animals and leaves little residue on treated plants.  This biocontrol could also benefit organic growers, because currently there is no available natural treatment for these extremely common pests.  While Muscodor albus doesn’t fight crime, it may progress as a useful biocontrol method for a different kind of villain.  Don’t expect this fungus to wear or cape, or even to star in a comic book, but you can expect Muscodor albus to continue making headlines as a potentially powerful biocontrol agent.

Want to learn more?  Check out the resources I used for this blog:

Fungal Fumes Clear Out Crop Pests

Scientists map the soybean genome and discover implications for the future of agriculture

Credit: Photo by Stephen Ausmus (USDA Agricultural Research Service). From "Mapping and Sequencing of Soybean Genome Paves the Way for Improved Soybean Crops".

by Allison Younkins

Soybeans: An insignificant plant, or the key to the future of agriculture?
What do a $30 billion dollar US industry and 1.1 million base pairs of DNA have in common?  They are both attributes of the soybean plant.  A tremendous group of researchers, including those at the University of Missouri, have completed a study that identified over 1 million base pairs of DNA in the soybean genome.  Funded by multiple organizations for over 15 years, this project may seem like an extensive amount of research for just one plant.  But the soybean is the second most profitable crop and it is used as a component of:

  • Human food
  • Livestock feed
  • Plastics
  • Some forms of biodiesel

Scientists at the University of Missouri and The U.S. Department of Agriculture predict that the soybean genome will allow researchers to increase soybean yield, resistance to drought, and resistance to disease.  And if you think soybeans don’t apply to you, just ask Henry Nguyen, director of the National Center for Soybean Biotechnology at the MU College of Agriculture, Food and Natural Resources.  He is currently working on an animal science project using the soybean genome to increase both protein and antioxidants in meat.

From the bench to the farm: How will the soybean genome impact agriculture?
Without experience mapping genomes, it might be difficult to see the implications of the soybean genome on our crops.  But the researchers have made it clear that it will have a direct impact.  The soybean genome is a key component to a researcher’s ability to link the plant’s physical traits to genes and to alleles, which are different versions of the same gene.  These genes could control any aspect of the soybean, but researchers are most excited about genes that control seed yield and disease resistance.  In the future, researchers will manipulate these genes to produce a desired physical trait.

What you need to know: How soybean research affects all of us
This example of soybean research is one of numerous projects in the field of agricultural science.  Agricultural science is one of the few fields that affects people from every socioeconomic status and people from every country.  Fresh fruits and vegetables are often too expensive for families with low income.  This affects the health of our nation’s children as well as their families.  By increasing yield and lowering losses to disease, the price of vegetables would decrease.  In a global perspective, agricultural science is an invaluable tool for the fight against world hunger.  If scientists can develop drought resistance plants by finding the appropriate genes, food production in developing nations would be increased tremendously.  It just goes to show that big things do come in small soybean shaped packages.

Looking for more information? Check out the resources I used for this blog:

MU Researchers Fight World Hunger by Mapping the Soybean Genome

Soybean Genome Sequenced: Foundational Research Will Help Improve Soybeans And Other Legumes

Mapping and Sequencing of Soybean Genome Paves the Way for Improved Soybean Crops

Allison Younkins

Allison is a sophomore at Dickinson College and a Biochemistry & Molecular Biology major. During the summer, she interns with the United States Department of Agriculture/Agricultural Research Service and works in a plant virology laboratory.  As a student, Allison is a tour guide and an intern in the Dickinson College Admissions office.  She is also involved in Greek Life and The Dickinson College Panhellenic Council.