The rainbow papaya is a tasty tropical fruit with a creamy, ­yellow-orange flesh. Who could possibly not like that?

Meet Jeffrey Smith of the Institute for Responsible Technology, based in Fairfield, Iowa. He readily admits to not being a doctor, or any sort of scientist. But he’s pretty sure eating that kind of papaya will make you more susceptible to colds, hepatitis and HIV.

Despite the lack of any verifiable evidence backing up that assertion, a lot of people believe him.

That’s because rainbow papaya is “genetically modified,” a term that has become vilified in recent years. It means that something has been bred to have more desirable traits — in the case of the rainbow papaya, it has been vaccinated against ringspot, a disease that killed off Hawaii’sconventional papaya trees. To growers on the island, rainbow papaya is not some menacing interloper. It’s their future.

The rising tension between ­anti-GMO crusaders and researchers striving to improve crops is the focus of “Food Evolution,” a documentary narrated by science superhero Neil deGrasse Tyson.

[Neil deGrasse Tyson explains the big bang — and everything else]

The film is one of more than 180 selections from 32 countries being screened across Washington March 14-26 as part of the Environmental Film Festival in the Nation’s Capital (dceff.org). The largest and longest-running environmental film festival in the country turns 25 this year, and the schedule features a wide range of topics: baby elephants, coral reefs, nuclear power, recent political developments.

Opening night at the National Geographic Society features 2017 Sundance selection “Water & Power: A California Heist,” Oscar-winner Alex Gibney’s exploration of California’s water crisis. Stick around after the show for a discussion with director Marina Zenovich and environmental attorney Adam Keats, who is featured in the film.

There are similar panels of experts after most of the documentaries, including “Food Evolution,” which screens March 17 at the Carnegie Institution for Science. So prepare your papaya questions for filmmaker Scott Hamilton Kennedy, Johns Hopkins University bioethicist Gail Geller and Cornell plant biologist Sarah Davidson Evanega.