WEBVTT - Could Genetics Grow a Square Tomato?

0:00:02.000 --> 0:00:07.080
<v Speaker 1>Welcome to brain Stuff from how stuff works. Hey, brain Stuff,

0:00:07.080 --> 0:00:09.719
<v Speaker 1>I'm Lauren vocal Bomb, And if you wander the protocyle

0:00:09.760 --> 0:00:12.399
<v Speaker 1>at your local grocery store, you'll find a dazzling variety

0:00:12.440 --> 0:00:15.840
<v Speaker 1>of tomatoes, from cherry or grape shaped to massive beefsteaks

0:00:16.040 --> 0:00:20.040
<v Speaker 1>and gnarly heirlooms. The same with squash, potatoes, cucumbers, and

0:00:20.160 --> 0:00:24.200
<v Speaker 1>leafy greens. This bounty of diverse colors, shapes, and sizes

0:00:24.320 --> 0:00:27.920
<v Speaker 1>isn't the result of natural selection, but rather human selection.

0:00:29.080 --> 0:00:32.720
<v Speaker 1>Over millennia, farmers and plant breeders have spotted useful mutations

0:00:32.720 --> 0:00:36.200
<v Speaker 1>and fruits and vegetables. Taste your fruit better, yields novel shapes,

0:00:36.479 --> 0:00:40.559
<v Speaker 1>and preserved those traits through conventional breeding techniques. The process

0:00:40.600 --> 0:00:43.440
<v Speaker 1>is slow, but if you cross different strains enough times,

0:00:43.680 --> 0:00:46.800
<v Speaker 1>eventually you may create something new enough and marketable enough

0:00:46.920 --> 0:00:50.680
<v Speaker 1>to be called its own variety. That slow and steady

0:00:50.680 --> 0:00:53.200
<v Speaker 1>conventional breeding process is about to get a big boost

0:00:53.200 --> 0:00:57.000
<v Speaker 1>from advances in genetic mapping. With a tomato or cucumber

0:00:57.080 --> 0:00:59.920
<v Speaker 1>genome in hand, plant breeders don't have to wait months

0:01:00.000 --> 0:01:02.400
<v Speaker 1>for a tomato plant to bear fruit to know whether

0:01:02.440 --> 0:01:06.080
<v Speaker 1>the tomatoes will be pear shaped. Or round. Instead, they

0:01:06.080 --> 0:01:08.679
<v Speaker 1>can look for tell tell markers and a seedling's DNA,

0:01:09.000 --> 0:01:12.679
<v Speaker 1>the code for specific fruit shape, size, and color. This

0:01:12.760 --> 0:01:16.360
<v Speaker 1>technique of marker assisted selection promises to cut years off

0:01:16.400 --> 0:01:20.800
<v Speaker 1>the traditional plant breeding process. One Esther vander Nap is

0:01:20.840 --> 0:01:23.560
<v Speaker 1>at the forefront of genetic research into exactly how it

0:01:23.560 --> 0:01:26.360
<v Speaker 1>plant's DNA instructs its fruit to grow long and lean

0:01:26.400 --> 0:01:28.959
<v Speaker 1>like a hothouse cucumber, or round and squat like a

0:01:29.000 --> 0:01:32.400
<v Speaker 1>beefsteak tomato. In her lab at the University of Georgia,

0:01:32.680 --> 0:01:35.679
<v Speaker 1>post docs and undergraduates sliced tomatoes in half and place

0:01:35.720 --> 0:01:38.560
<v Speaker 1>them on a flatbed scanner to measure the precise shapes

0:01:38.600 --> 0:01:42.839
<v Speaker 1>and sizes produced by different genetic combinations. In a paper

0:01:42.840 --> 0:01:46.240
<v Speaker 1>published in November of twenty eighteen in the journal Nature Communications,

0:01:46.560 --> 0:01:49.560
<v Speaker 1>vander Nap announced the discovery of two families of genes

0:01:49.680 --> 0:01:52.240
<v Speaker 1>that appear to play key roles in making fruits and

0:01:52.320 --> 0:01:56.760
<v Speaker 1>vegetables either round or long. Fruits and vegetables are technically

0:01:56.800 --> 0:02:00.000
<v Speaker 1>a plant's edible organs, and those organs grow and develop

0:02:00.080 --> 0:02:04.480
<v Speaker 1>up through cell division. She explained, to make a certain shape,

0:02:04.520 --> 0:02:07.040
<v Speaker 1>like a longer round shape, you need to have certain

0:02:07.080 --> 0:02:10.720
<v Speaker 1>patterns of cell division, either the cells divide horizontally or

0:02:10.720 --> 0:02:14.560
<v Speaker 1>they divide vertically, which makes sense. The more in organ

0:02:14.639 --> 0:02:17.880
<v Speaker 1>cells divide horizontally by splitting down the middle, the more

0:02:17.919 --> 0:02:21.079
<v Speaker 1>they're going to build up tissue horizontally, creating a fatter,

0:02:21.320 --> 0:02:25.720
<v Speaker 1>rounder fruit. What vander Nap and her colleagues discovered in

0:02:25.760 --> 0:02:29.240
<v Speaker 1>the tomato genome is a specific gene called ovate that

0:02:29.280 --> 0:02:32.680
<v Speaker 1>appears to be responsible for creating proteins that tell cells

0:02:32.720 --> 0:02:36.320
<v Speaker 1>to divide in a vertical pattern. When more cells split

0:02:36.440 --> 0:02:39.640
<v Speaker 1>side to side, the growth pattern produces an elongated fruit.

0:02:40.320 --> 0:02:43.320
<v Speaker 1>Ovate is the difference between a perfectly round cherry tomato

0:02:43.520 --> 0:02:47.920
<v Speaker 1>and an oblong plum tomato. Wild tomatoes, like the native

0:02:48.000 --> 0:02:51.959
<v Speaker 1>varieties found in Peru, Ecuador, and Mexico, are invariably small

0:02:52.040 --> 0:02:54.760
<v Speaker 1>and round, says vander Nap, which means pear shaped and

0:02:54.800 --> 0:02:58.720
<v Speaker 1>other elongated tomatoes are mutations that came along later as

0:02:58.720 --> 0:03:02.280
<v Speaker 1>far back as the ninety Plant biologists called the elongation

0:03:02.360 --> 0:03:05.480
<v Speaker 1>mutation ovate, but had no clue about the actual genetic

0:03:05.560 --> 0:03:08.840
<v Speaker 1>mechanism behind it. But vander Nap and her team identified

0:03:08.880 --> 0:03:12.000
<v Speaker 1>the ovate protein as well as another family of proteins

0:03:12.000 --> 0:03:15.520
<v Speaker 1>called trms that interact with ovate, and it provides another

0:03:15.560 --> 0:03:18.560
<v Speaker 1>tool to plant breeders who are using marker assisted selection.

0:03:19.400 --> 0:03:21.920
<v Speaker 1>If the ovate n tr M markers are present, you

0:03:21.919 --> 0:03:24.880
<v Speaker 1>can be sure the fruit will be elongated. If one

0:03:24.960 --> 0:03:28.080
<v Speaker 1>or the other is missing, it's backed round. Vander Napp

0:03:28.160 --> 0:03:30.760
<v Speaker 1>says this will speed up the breeding process and let

0:03:30.760 --> 0:03:34.320
<v Speaker 1>growers focus on trickier traits like yield and pest resistance

0:03:34.480 --> 0:03:36.839
<v Speaker 1>that aren't as easily linked back to one or two

0:03:36.920 --> 0:03:41.640
<v Speaker 1>specific genes. So now the question is do these advances

0:03:41.640 --> 0:03:44.240
<v Speaker 1>in plant genetics mean that your produce I will soon

0:03:44.240 --> 0:03:48.640
<v Speaker 1>include square tomatoes or pyramid shaped pumpkins. Not likely, says

0:03:48.720 --> 0:03:52.560
<v Speaker 1>vander Nap, but not because it's technically impossible. She says.

0:03:52.600 --> 0:03:55.240
<v Speaker 1>There are tons of bizarre mutations in the tomato genome

0:03:55.360 --> 0:03:58.600
<v Speaker 1>that result in odd looking fruits, and since those mutations

0:03:58.600 --> 0:04:02.000
<v Speaker 1>are naturally occurring, they could be isolated and replicated in

0:04:02.040 --> 0:04:05.520
<v Speaker 1>the lab. But the problem with square tomatoes and other

0:04:05.560 --> 0:04:09.520
<v Speaker 1>oddball shaped fruit is twofold, vander Nap says, First, there's

0:04:09.520 --> 0:04:12.960
<v Speaker 1>the GMO problem. If plant breeders use gene editing to

0:04:13.080 --> 0:04:16.479
<v Speaker 1>directly tweak or replace genes in food plants, those trains

0:04:16.520 --> 0:04:19.640
<v Speaker 1>are considered GMO, and some people get freaked out by

0:04:19.640 --> 0:04:23.080
<v Speaker 1>the GMO label, even though genetically modified organisms as a

0:04:23.120 --> 0:04:28.799
<v Speaker 1>category are no less or more safe than conventionally modified organisms. Second,

0:04:29.040 --> 0:04:32.080
<v Speaker 1>exciting new fruit and vegetable shapes may not shape up

0:04:32.080 --> 0:04:35.800
<v Speaker 1>in other ways. Vander Nap said, some mutations are so

0:04:35.880 --> 0:04:38.320
<v Speaker 1>bizarre that no grower would grow them because they have

0:04:38.400 --> 0:04:41.080
<v Speaker 1>lots of other problems. They only have a few fruit

0:04:41.120 --> 0:04:43.920
<v Speaker 1>per plant, or they taste terrible because when you grow

0:04:43.920 --> 0:04:45.960
<v Speaker 1>a fruit in a really odd shape, you mess up

0:04:46.000 --> 0:04:48.800
<v Speaker 1>the hormone balance. It may not be very juicy or

0:04:48.880 --> 0:04:52.080
<v Speaker 1>tasty at all. If you really want to grow a

0:04:52.080 --> 0:04:54.880
<v Speaker 1>square tomato, says vander Nap, just put a box around it,

0:04:54.960 --> 0:04:57.680
<v Speaker 1>like you may have seen downe with other fruit like watermelons.

0:04:58.000 --> 0:05:00.120
<v Speaker 1>Should those hit the scene at a premium price, you

0:05:00.120 --> 0:05:02.560
<v Speaker 1>can always try growing your own at home. There are

0:05:02.560 --> 0:05:05.919
<v Speaker 1>plenty of instructions online for building your own square fruit boxes.

0:05:11.040 --> 0:05:13.480
<v Speaker 1>Today's episode was written by Dave Ruse and produced by

0:05:13.480 --> 0:05:15.880
<v Speaker 1>Tyler Clang for i Heeart Media and How Stuff Works.

0:05:16.320 --> 0:05:18.560
<v Speaker 1>For more on this and lots of other well rounded topics,

0:05:18.680 --> 0:05:32.320
<v Speaker 1>visit our home planet, how stuff Works dot com