# With genetic modification, can we make naturally occurring popcorn?

I thought it would be interesting if someone made naturally occurring popcorn. Like if we made this genetically modified corn reached a certain temperature, the kernels would dry out and explode. but can we actually make corn like this?

• By naturally occurring "pop corn" I am assuming you mean "Corn that would explode or spontaneously combust?" The earliest known popcorn was discovered at an archeological dig site in Peru and dates to 4700 BC... It's an almost 7,000 year old invention of man. Modern pop corn is a certain strain of Flint/Indian/Ornamental Corn (Zea may everta), which was cultivated as early as 1000 BC. So sans heat source, Pop Corn is as old as if not older than Zoroastrianism... the oldest continually practiced religion in the world! Mar 16, 2021 at 13:59
• @hszmv I did not know Pop Corn was a religion! That is very cool and makes sense in retrospect. Mar 16, 2021 at 14:30
• I have a sci fi character who has corn, and for religious reasons wants to recreate the practices of the ancients. Only the corn won't pop, no matter what she tried. Her next attempt was going to be explosives... Mar 16, 2021 at 14:35
• @DWKraus: Has she tried "fire?" Prior to Popcorn becoming a big snack food, it was usually cooked by pouring kernals into a kettle and cooking over a fire or wood burning stove. It's a 7,000 year old science... not rocket surgery. Mar 16, 2021 at 14:49
• @Willk: It's not a religion... it just predates the oldest still in practice religion... which also introduced concepts like Monotheism and Monism and may have influeced every major world religion today... Popcorn was a snack, not a God (I do think Native Americans have "gods of corn" as several seem to be one of only two societies to use food stuff as a commodity of exchange rather than a metal (the other being Japanese tying the Yen to Rice). Mar 16, 2021 at 14:53

Actual popcorn is made when pressure built up inside the kernel makes it pop

A popcorn kernel's strong hull contains the seed's hard, starchy shell endosperm with 14–20% moisture, which turns to steam as the kernel is heated. Pressure from the steam continues to build until the hull ruptures, allowing the kernel to forcefully expand, from 20 to 50 times its original size, and then cool

I see two possible paths to build up a lot of pressure:

1. build pressure inside the kernel in the same way as the squirting cucumber does

The tissue in the fruit of the Ecballium elaterium that surrounds the seed is thin walled. The pressure to release the seed is created by the increased concentration of glucoside and elaterinidin in low volumes of cytoplasm. This creates an osmotic pressure of up to 27 atms.

However if you follow this path you need to have a kernel which is strong enough to withstand the pressure and then pops open when separated from the plant: not impossible, but tricky.

1. Follow the path of the bombardier beetle by having the two reactants mix up at a certain point and produce pressurized steam inside the kernel.

There are two large glands that open at the tip of the abdomen. Each gland is composed of a thick walled vestibule which contains a mixture of catalases and peroxidases produced by the secretory cells that line the vestibule. Both glands are also made up of a thin-walled and compressible reservoir which contains an aqueous solution of hydroquinones and hydrogen peroxide.

When the beetle feels threatened it opens a valve which allows the aqueous solution from the reservoir to reach the vestibule.

The net reaction $$C_6H_4(OH)_2(aq)+H_2O_2(aq) \to C_6H_4O_2(aq) + H_2O(l)$$ is very exothermic, and the released energy raises the temperature of the mixture to near 100 °C, vaporizing about a fifth of it. The resultant pressure buildup forces the entrance valves from the reactant storage chambers to close, thus protecting the beetle's internal organs.

• It is probably possible given the huge range and complexity of biochemical reactions, however such a thing is certainly not likely to happen naturally and the genetic changes required are probably very extensive and there is no way to determine what they are. Should a sufficiently strong selective pressure occur for this and enough time, nature would probably come up with something completely different. But yes its doable. Mar 16, 2021 at 13:25

There are multiple existing seed pod casings that do this.

If the actual plant embryo goes pop like it does in popcorn, that reduces viable offspring. So you would expect it to be selected against naturally.

Plants that have the pod/casing go pop, spraying seeds is dispersal system. It does work for some plants as witnessed by those plants that have that feature.

The one I encountered when i was young was a weed that had tiny pods that resembled pea pods. They were about 1 mm diameter 20mm long that just lightly touching them would cause rapid deformation of the pod and seeds being ejected from the pod. At the right time of year you can walk through these plants and be sprayed with seeds.

Some example species names that I found in a search. Key words "shooting seed": Ruellia tuberosa. Hura crepitans "which can explode when ripe, splitting into segments and launching seeds at 70 metres per second"