Short Wave Podcast Summary

Episode: An Apple Is An Ovary: The Science of Apple Breeding
Date: November 18, 2025
Hosts: Emily Kwong, Hanna Chin
Featured Experts: Dr. Susan Brown (Cornell Agritech), Ben Gutierrez (USDA Plant Geneticist)

Overview

This episode dives into the mind-bending science of apple breeding, revealing why your favorite apples are essentially clones, how entirely new varieties like the Honeycrisp or Rosalie are painstakingly created, and why preserving apple diversity could shape the future of what we eat. The hosts mix playful banter with a look behind the scenes at Cornell’s world-renowned apple breeding lab and the USDA’s “Noah’s Ark” of apple diversity.

Key Discussion Points & Insights

Apple Cloning and Propagation

• All commercial apples are clones: Whether you pluck a Rosalie in Maryland or buy one in New York, it’s genetically identical to every other Rosalie.
  • “Those Rosalie apples that you saw, they’re the same Rosalies that I might see apple picking in New York. They’re clones.” — Hannah Chin [00:42]
  • This is accomplished by grafting cuttings (buds) from one tree onto the rootstock of another, ensuring that every tree grows apples with identical DNA.
• Botanist’s take:
  • “Every leaf has the genetic potential to make a tree.” — Dr. Susan Brown [01:16]

How New Apples Are Born

• Cross-breeding apples: To make a new apple variety, scientists like Dr. Susan Brown manually control apple pollination:
  • Remove petals and anthers from the 'seed parent' flower to prevent pollination by bees, then apply pollen from a chosen 'pollen parent.'
  • Comparing the process to reality TV:
    • “And apparently there's several rounds of testing. It's like the American Idol, but of apple tasting.” — Hannah Chin [11:33]
    • “And she’s Simon Cowell.” — Emily Kwong [11:39]
• Labor-intensive magic:
  • Each prospective apple is hand-pollinated, apples are grown, seeds extracted, and seedlings planted—then comes the taste test.
  • “I create thousands of these hybrids, and then, yes, I must eat them... I can be brutal. I have two wonderful children. I had to keep them. My apples, I don't have to keep.” — Dr. Susan Brown [10:44]

The Science: Apples as Ovaries & Genetic Goldmines

• Biology 101:
  • “When an apple tree is still in flower, bees visit... that apple flower becomes an apple, which you can kind of think of like a fertilized ovary.” — Hannah Chin [05:47]
  • Every apple seed is unique—just as you are a mix of both parents, so is each apple seed a mix of two apple trees.
• Genetics complexity:
  • “There are 54,000 genes in apples, more than in humans.” — Hannah Chin [12:45]
  • This genetic complexity is both a challenge (makes selective breeding slower) and an opportunity (more variety and potential).

Modernizing Apple Breeding

• DNA Marker-Assisted Selection:
  • Researchers are developing methods to identify desired traits earlier, by reading gene markers at the sapling stage.
  • “Let’s see, on the genetic level, whether we can find a strand of DNA that matches whether it’s red or yellow... You can use that marker to select at the seedling stage so before they even fruit.” — Dr. Susan Brown [12:14]
  • Full reliance on this technology awaits further research due to apples’ genetic complexity.

Preserving Apple Diversity for the Future

• “Noah’s Ark” of apples: The USDA runs a unique orchard with 5,000 different, wild, and rare apple varieties to safeguard genetic diversity.
  • “Each one of them is totally unique. Some... huge and round and green... some tiny... so red that they were almost purple.” — Hannah Chin [14:08]
  • Apples can’t be preserved merely as seeds—their next generation will always be genetically different.
  • “Apples need to be preserved as trees because... the seed... is going to be something different.” — Ben Gutierrez [14:20]
• Long-term vision: Breeders and geneticists are seeking unique genes that may not taste good today but could ensure disease resistance or other future traits.
  • “This is maybe 50 to 60 years away from becoming optimistic... But it could have an interesting trait for, again, disease resistance...” — Ben Gutierrez [15:06]

Notable Quotes & Memorable Moments

• On the odd truth about apples:
  • “Oh, an apple is an ovary.” — Emily Kwong [06:12]
• Joking about lineage:
  • “It’s like a Maury Povich episode up in these apples.” — Emily Kwong [06:40]
• On the patience needed:
  • “On average, it takes maybe 20 years to develop a new apple. There’s a lot of waiting and patience and work involved.” — Hannah Chin [09:57]
• The genetic lottery:
  • “I want that one really bright child, the shining star of apples... My apples, I don’t have to keep.” — Dr. Susan Brown [10:44]
• On bad apples:
  • “I’m sure that there are some that are not good.” — Hannah Chin [11:16]
  • “Oh, there’s many. They’re called spitters because you spit them out.” — Dr. Susan Brown [11:26]
• On apple genome complexity:
  • “Wait, more than in humans?” — Emily Kwong [12:55]
  • “Yeah.” — Susan Brown [12:57]
• The vision for the future:
  • “What’s so amazing about apple is just its broad genetic diversity. Like, it can’t self-pollinate. So each generation of apple is some new cross that’s never been done before. So there’s, you know, almost unlimited potential.” — Ben Gutierrez [13:29]

Timestamps for Important Segments

• Apple varieties and cloning explained: [00:28]–[02:18]
• Introduction to apple breeding and Susan Brown: [02:44]–[04:00]
• How apples breed, apples as ovaries: [05:36]–[06:27]
• Manual cross-breeding process: [07:04]–[10:17]
• Taste testing and selection: [10:44]–[11:39]
• Apple genetics and DNA marker research: [11:42]–[12:58]
• Apple diversity preservation with Ben Gutierrez: [13:29]–[15:32]
• Closing reflections on the future: [15:32]–[15:41]

Tone & Style

The episode mixes witty banter (“It’s like a Maury Povich episode up in these apples.”), friendly analogies, and deep-dive scientific reporting to make apple genetics and breeding accessible and fun for a general audience.

Conclusion

This Short Wave episode delivers a vibrant, hands-on look at the science and art of apple breeding. Listeners come away with a newfound appreciation for every crunchy bite—knowing the genetics, history, and dedicated work behind their favorite varieties, and the ever-evolving search for the apples of tomorrow.