Extracting DNA From Strawberries

About the Experiment

Deoxyribonucleic acid (DNA) is the molecule that carries genetic instructions in all living organisms. It is found inside cells and is protected by membranes. In other words, DNA tells cells how to grow and work.

Researchers extract DNA from strawberries to determine which cells carry the most promising traits, such as size, color, taste, and disease resistance. Using common household items like dish soap, salt, and rubbing alcohol, we can break open the cells and see what DNA looks like with our own eyes! This experiment is easy to do at home or in school. Parental or teacher supervision is recommended.

Details

Age: 8-12 | Time: 30 Minutes | Difficulty: Easy

What You Will Need

• 3-4 fresh strawberries

• 1 sealable plastic bag

• A few drops of dish soap

• ½ teaspoon of table salt

• ½ cup of water

• 1 coffee filter or cheesecloth

• 1 clear glass or cup

• 2-3 tablespoons of rubbing alcohol (must be chilled in freezer for at least 30 minutes). Chilled alcohol helps the DNA clump together and become visible faster.

• 1 spoon or stir stick

Safety Note: Rubbing alcohol is flammable. Please have an adult assist in handling rubbing alcohol carefully and keep it away from flames.

Let's Do This

Prepare the Strawberry:

• Remove the green leaves from the strawberries and put the strawberries in the sealable plastic bag. Mash the strawberries well until they become a pulp (or soupy).

Make the Extraction Solution:

• Mix ½ cup of water, a few drops of dish soap, and ½ teaspoon of salt in a cup.

• What’s happening here? The soap breaks open the cell walls, and the salt helps release the DNA.

Combine the Strawberry Pulp and Extraction Solution:

• Pour the extraction solution into the bag with the mashed strawberries.

• Seal the bag and gently mix the strawberries and extraction solution for 1 to 2 minutes.

Filter the Strawberry Mixture:

• Place a coffee filter over a clear glass or cup and pour the strawberry mixture through it.

• Let the liquid drip into the glass or cup. This is the DNA-containing solution.

Add Alcohol to the Strawberry Liquid:

• Slowly pour the chilled rubbing alcohol down the side of the glass so it forms a layer on top of the strawberry liquid.

• Tip: Do not mix the liquid. The DNA will appear at the boundary!

Let’s Look At The Results!

• White, stringy clumps will appear in the glass or cup. This is strawberry DNA! Use a spoon or stick to lift it out.

• Make sure to wash your hands after the experiment.

Observations

• Each ingredient has a role in breaking down cells and making DNA visible to the human eye. Dish soap breaks cells open. Salt helps DNA stick together. DNA does not dissolve in alcohol, so it becomes visible.

• Did you know that strawberries have more DNA than humans? Strawberries are octoploid which means their cells contain eight (octo) sets of chromosomes (ploid) in each cell. Humans are diploid with only two (di) sets of chromosomes (one set from each parent). Because of this, it is easier to extract DNA from strawberries.

• Scientists use similar methods to extract DNA for genetic research, forensics, and agriculture.

• This experiment shows how chemistry and biology work together.

• You can do this experiment with other fruits like bananas, kiwis, peas, mangos, and papayas.

To learn more about ARS’s research on strawberries, click here.

Download the printable "Extracting DNA From Strawberries" project PDF:
https://www.ars.usda.gov/ARSUserFiles/oc/AgLab/projects/StrawberryDNA/Extracting-DNA-From-Strawberries.pdf 

Putting Topsoil Back Where It Belongs

Hilly farms lose topsoil from upper slopes and accumulate it downslope, causing big yield differences. Researchers at Integrated Cropping Systems Research Unit in Brookings, SD, tested moving 6–8 inches of rich soil from lower slopes back to eroded upper areas. The added soil greatly improved nutrients, water availability, and boosted corn and soybean yield by up to roughly 50%. Removing soil from lower slopes had smaller effects but reduced yields in wet years. The study suggests targeted soil‑landscape restoration can help farmers recover productivity on severely eroded land. Click here to learn more.

Refilling America’s Thirsty Aquifers

Farm irrigation in the U.S. relies heavily on groundwater, but many aquifers are being depleted faster than they can naturally refill. Researchers with the Agricultural Research Service’s (ARS) Watershed Physical Processes Research (WPPR) unit, part of the National Sedimentation Laboratory in Oxford, MS, have demonstrated a rapid, safe way to recharge the Mississippi River Valley Alluvial Aquifer by pumping naturally filtered river water into it through the Groundwater Transfer and Injection Pilot project. In tests, aquifer levels rose 1–7 feet within a mile of injection wells. This managed aquifer recharge approach, long used elsewhere, could help counter severe groundwater declines in the Mississippi Delta, protect ecosystems, and secure water for agriculture and communities. Click here to learn more.

Can You Grow Plants in Water?

About the Experiment

Hydroponics is the technique of growing plants using a water-based nutrient solution rather than soil. Hydroponic production systems are typically used by small farmers and commercial enterprises, but they are also being increasingly used in urban areas like cities where there may not be enough fertile land to grow crops.

Hydroponics allows farmers to grow their fruits and vegetables in a controlled environment, but it also entails using more energy and possibly more water. How does hydroponics affect the growing process, and how do the fruits and vegetables taste? Let’s find out by comparing hydroponics with traditional growing in soil outdoors.

Details

Age: 7-8 | Time: 3-4 Weeks | Difficulty: Moderate

What You Will Need

For the Hydroponics

• 6-12 small cups

• Styrofoam board (about 1” thick)

• Sponges or rinsed clay pebbles

• Hydroponic nutrient solution (premixed,
  kid safe)

• Plastic container (not clear)

For the Soil

• 6-12 small pots or cups with
  drainage holes

• Potting mix with slow releasing
  fertilizers (not gardening soil)

• Watering can or squeeze bottle

For Both

• Seeds of leafy green vegetables
  or herbs, such as leaf lettuce,
  basil, arugula, or microgreens

• Water

• Ruler, labels, tape, marker 

Let’s Do This!

Prepare the Hydroponics

1. Fill the container with water.

2. Cut the Styrofoam board to fit the container and cut holes in the board to fit the plant cups. Add a few more small holes inside each cup place holder to give the plant roots room to grow.

3. Ask an adult to drill or cut a small hole in each cup.

4. Ask an adult to cut the sponges into a small square to place inside the cups. Form a hole in the sponges for seed germination. Or place the pebbles on the bottom of the cup.

5. Ask a parent to help dilute the nutrient solution per instructions on the label and volume of water in the container.

Prepare the Soil

6. Fill the pots 4-6” with moist potting mix (pre-wet so it’s evenly damp).

7. Make a small hole and plant the seeds at label depth (about 1/4 inch).

8. Water gently so soil is evenly moist, not soggy.

Planting and Care

9. Use the same seed variety for the hydroponics and soil.

10. Plant 1-2 seeds per cup/pot and then cover them from light for 3-4 days under room temperature. You can cover with aluminum foil if you like. Thin to 1 plant after germination.

11. Once seedlings are germinated, place the hydroponic cups close to a window with some hours of available sunlight (or you can use an LED light bulb). Place the soil cups outside in available full sunlight. If there is a chance of frost, bring the soil cups in at night.

12. For the hydroponics, add more nutrient solution and water if the water drops too low. For the soil, water just a little every day; avoid soaking the cups.

13. Observe all plants for 3-4 weeks. Use a spreadsheet to track results, such as plant height, fresh weight, and food taste between plants in the hydroponic and soil experiments.

Observations

1. Which plants grew faster and fuller using the hydroponics technique?

2. Which plants grew faster and fuller using the soil technique?

3. Which technique produced the best results overall?

4. Which technique was easier to follow throughout the process?

5. What aspect of the experiment surprised you?

6. Do you think you can grow your own fruits and vegetables using hydroponics?

Want to learn more about hydroponics research? Check out this page: https://www.ars.usda.gov/research/project/?accnNo=443702 

Download the printable "Can You Grow Plants in Water?" project PDF: https://www.ars.usda.gov/ARSUserFiles/oc/AgLab/projects/GrowPlantsInWater/Can-you-Grown-Plants-in-Water.pdf 

The Beans About Yellow Beans

Iron deficiency is one of the leading nutritional deficiencies worldwide, affecting a third of the global population. In the United States, 40% of females ages 12-21 could be iron deficient, up from previous estimates of about 16%.  

Beans are an important staple crop, providing essential nutrients to hundreds of millions of people globally. Naturally rich in iron, beans also contain a class of compounds known as polyphenols that inhibit the absorption of iron during digestion.

As part of efforts to improve nutritional benefits of dry beans, ARS researchers and their partners developed “Manteca” yellow bean varieties that contain high levels of the promoting (good) polyphenols and low levels of inhibitory (bad) polyphenols. The results are new yellow beans that contain more absorbable iron. In addition to helping alleviate iron deficiency, the “Manteca” bean boils in less than 20 minutes, tastes great, and has superior milling properties for processing into pasta and other food products.  

Watch this video to learn more. https://www.youtube.com/watch?v=NKk8v_agpYc

Happy Animals, Healthy Farms: Researchers Look for Ways to Improve Livestock Quality of Life

Researchers at the ARS Livestock Behavior Research Unit in West Lafayette, IN, are exploring how better treatment of farm animals can boost both their well‑being and farm productivity. Using modern tools like automated feeders and behavior‑tracking sensors, they study ways to reduce pain, detect illness earlier, and protect livestock from rising heat stress. 

Their work spans cattle, swine, and poultry, with a focus on keeping animals healthier, more resilient, and more comfortable. The team emphasizes that strong animal welfare isn’t just ethical, it’s essential for sustainable, trusted food production. 

Click here to learn more. 

ARS Helps Fill Nets with Better Salmon

ARS researchers at the National Cold Water Marine Aquaculture Center in Franklin, ME, are supercharging America’s Atlantic salmon – one of the most popular farm-raised fish varieties in the country. For nearly 20 years, they’ve used traditional selective breeding techniques to create faster‑growing, sea‑lice‑resistant fish with better fillets—traits that help U.S. producers stay competitive. 

With about 150 improved salmon families supplying eggs to fish farms each year, their work keeps the industry strong and Americans well fed. 

Click here to learn more

A Holistic Approach is Reshaping Livestock Production

ARS researchers at the U.S. Meat Animal Research Center in Clay Center, NE, are partnering with livestock producers to build more resilient farming systems for their cattle.  Using a biology-based approach, researchers are studying how genetics, environment, management, and socio‑economic factors interact to shape livestock productivity and sustainability. This holistic framework supports better genetic matching, improved management practices, and responsiveness to societal expectations for quality and animal welfare. 

ARS research also incorporates emerging technologies and has already produced practical tools—such as genetic tests—that help meat producers enhance efficiency and product quality. 

Click here to learn more. 

Nutritional Facts or Fiction? 

It's a fact of life; good nutrition is vital human health. But how to find reputable resources on eating healthy can be daunting. 

If, like most people, you are spending time online, reading the news, surfing the web, or connecting on social media, you may be inundated with nutrition tips and claims about eating enough protein, drinking enough water, eating enough fiber, and so on. While nutrition is a very important topic, not all of the information you read is reliable. The Internet is full of fraudulent health claims and inaccurate or misleading information about diets, nutritional supplements, and weight loss products. 

So, how do you avoid falling victim to nutritional misinformation, especially on social media? 

Watch this webinar: https://www.youtube.com/watch?v=VzixmuKCyGY to learn from registered dietitians Courtney Thompson and James Cain as they answer popular questions about nutrition and how to find reputable, science-driven information about diets, fats, carbs, supplements, and disease prevention. 

A New Twist to the Pasta Bake

Baked goods and pastas are two popular food types for many American families. In most cases, baking cakes, breads, and cookies requires a different type of wheat (one that can be ground into a flour) than making pasta, which is usually made from durum wheat. However, a new USDA-ARS Soft Spring Durum wheat, being released as “USDA Morris”, represents a new variety of soft spring durum that not only grows well in harsh environments typical of durum wheat, but also features novel end-use traits that allow it to be milled conventionally, producing flour instead of the more coarse semolina.

USDA Morris features novel baking quality genes that will allow baking enthusiasts to use its yellowish flour to bake it all—bread, cookies, and pasta—while still benefiting from the same health traits associated with traditional durum, such as high protein and carotenoids. The yellow pigmentation of the soft spring durum bread makes it novel, intriguing, and appealing to bakers, consumers, and culinary enthusiasts. And it still can be used to make healthy, delicious pasta and noodles. Learn more about this new variety here.