"let’s pick apples together this Sunday" -umshoot
So you’ll remember that I had a Winesap apple I wanted to eat because it was new and exciting! However, you’ll probably also recall that this variety is one that I had last year, and while I have deliberately not gone back and read what I used to think so as not to bias myself, I remember thinking the skin was much thicker that I would have liked. This apple is nearly circular top and bottom, with only a little pentagon shape, and very regular shoulders. The background color is greenish and the blush is purplish pinkish red with some paler stripes, and the lenticels are pale pink. I’m going to eat it.
Oh gosh. Starchy McStarch! My mouth is full of starchy apple juice. Yes, the skin is thick and vegetal, even bitter, and the apple flesh is hard and crunchy. The flavor is not great. Why would someone market this? Ugh. Disappointed, although not surprised.
Ok. Flavor. It’s starchy and a little sweet with a flavor like apple juice diluted in vegetable water. It isn’t good. I don’t want to talk anymore about it.
Even the inside flesh is still green-tinged. Sigh.
I thought I could go to a writing thing but I can’t because of timing.
So I didn’t write on my blog because I was indoors and not outdoors and I didn’t eat most fruits (occasionally melon) and I was so sad because I wasn’t sciencing and careering and whatever. But then I realized that I am actually doing cool things anyways and also I’m fine and also I still have some interesting ideas. This is what’s been going on for me.
All day long people I know sit on their computers and write thinkpieces about things they thought about, and all day long people post those items on Facebook and then other people repost them and mostly they say dumb things and sometimes they say smart things and that makes sense. However, I definitely get sad when people waste time on that stuff, because I think 1. at the end everything is the same as it was at the beginning so it was usually a useless article because 2. they don’t generally have access to any new information or analysis and mostly 3. I believe that most smart people do their best processing out of the public eye, and it makes me sad that some people sit and regurgitate ideas for other people for the likes and the lols and a sense of obligation to educate others when really they could be spending that time on other pursuits, like real live conversations with peers not to impress but to understand, or alone thought. So I didn’t want to write about my feelings because in my heart I was hating on others for writing about their dumb feelings, which I don’t respect in my heart. I respect my own feelings! I didn’t want them to become the subject of my own personal ridicule.
Then I applied on a whim for this thing called Tent, which is a Jewish food writing seminar in NYC, and I got in, and I guess that means I’ll spend a week in October learning about Jewish food and how to write about it. Sounds fun! This is part of my project of saying yes to interesting experiences, because I’m young and I can do these things and I will only learn/become supremely employable through adventures and experience and meeting people. Only, I stopped writing. Now I only write about antique Haggadot. This is a difficulty in the path of food writing!
It is from this moment in my life that I come back to my tumblr. It’s such a sweet format and so not intimidating, which is good for an easily intimidated lady such as myself. Still, original content is scary to produce! Therefore I am going to try to structure things, and write something about a food plant I ate or love every few days, and if this is the rule then I will try to follow it because it is much easier on me to follow a rule than to invent one.
So, um, shoot! Welcome back on board.
Viruses are tricky. A fungus can sometimes be controlled with an antifungal agent, a bacterium with an antibiotic, a competing weed with an herbicide, etc. That’s not really an option with viruses. Usually once you’ve got one, you’re stuck. So I’m going to talk about three AWESOME ways a person can protect a plant from catching a virus: cultural practices (like keeping insects away), using cleaned germplasm (starting off with a healthy plant), and GMOs (plants that the virus can’t infect because of genetics). If you read the previous post I wrote about viruses, you’ll notice that not all of them are bad for plants, but some of them are. Ok. Let’s go! It’s not gonna be boring because you’re having this knowledge adventure with me!
Our first way to avoid viruses is protecting a plant we already have growing from being infected by a virus. Remember, readers, that while viruses are sort of like living beings in that they can reproduce, they’re different from us in that they can’t move around unassisted. Viruses are reliant on other beings (or forces) to move from plant to plant. These beings can be insects, nematodes, or even people. There is a whole big chunk of literature about how viruses go into and out of insects, which I am not super excited about because (sorry entomologists) I don’t love insects. But if we’ve got leafhoppers or aphids, and we’ve got weeds or crop plants that are harboring viruses, those viruses might be hopping or squishing around on all our other plants. Ew.
All of this means that all the other ways we protect our plants from harm, meaning, by controlling the levels of insect infestation and managing weeds (the other two big areas of IPM), we’re also probably managing disease. Wow! Such synergy! Nematodes that live in soil can carry viruses also and maybe deserve their own post or at least a scan-through of this http://vegetablemdonline.ppath.cornell.edu/NewsArticles/Potato_Virus.htm. And, of course, we alive humans can be dumb and move viruses from one plant to another by using the same tools on one tree as the one before it without cleaning our tools because we’re humans and consequently bums. So practicing good hygiene and managing other aspects of a growing system is basically awesome for virus prevention.
All of this is no use, through, if the plant we start off with already has harmful viruses in it. Lots of viruses can be transmitted through seeds from the parent plant, and it’s possible, and sometimes a good idea, to buy seeds that are certified healthy. The biggest, most crazy adventure, though, is when we grow plants that are propagated vegetatively, which means that we grow new plants from little bits of old plants. An example is our friend the noble potato. Yes, potatoes can come from potato seeds inside potato fruits but, much like we discussed with apples, most of the potatoes we grow come from other potato tubers. This means that if a parent potato had a virus, there is a really good chance that all the new potatoes will too. Yum! Potatoes get attacked by lots and lots of viruses, so there can be a great advantage to a grower in buying certified virus-free potatoes to grow from. Cornell has a secret isolated potato breeding facility in a hidden location where they breed potatoes away from other potatoes so that the seed potatoes can be screened for viruses and a clean bit of germplasm can be produced for a new variety. This is important! I’m sure other places have secret facilities too, but I didn’t go to their schools so I don’t know.
- First of all, I recommend that everybody check out this (bch.cbd.int/database/attachment/?id=12294) 30-page summary from 2007 of what virus-resistant GMOs are, plus a review of studies about whether they’re safe, so that 1. you get a good visual sense of what viruses do, because there are great pictures and 2. you understand the concepts of a GMO as explained in the most understandable way possible (seriously, acronyms are explained on the side and everything) and 3. you hear a really good discussion of what risk is and what the risks with transgenic virus-resistant plants are, with the eventual goal that 4. you don’t sound dumb when you talk about this issue, because I like you and I want you to not sound dumb! Here’s a link again. bch.cbd.int/database/attachment/?id=12294 Even if you just skim it, I definitely recommend taking a look. I love this review article. It’s ideal. It’s got stories about papayas! It’s got pictures and diagrams! It’s one of the best things I ever saw at school.
With that said, I’ll briefly restate in a more convoluted and less illustrative way! Viruses have RNA so that they can get proteins made, and sometimes if we can put a copy of a section of that RNA into a plant’s genome, the plant will simply degrade the RNA of the virus when it is exposed to it. I like to imagine that when the plant finds itself expressing this non-plant protein, it gets super skeeved out and squashes all traces of the protein in itself or anyone else, sort of like if a person found himself saying the annoying catchphrase from a TV show, and got mad at himself, he might decide to never say that again, and also turn off the TV anytime that show was on. (Memes! Genes! Oh gosh!) A GMO plant that encounters a virus won’t let the virus replicate, and won’t get sick or show any symptoms, and will eventually crush the virus with its mighty defense system, which the GMO addition has triggered.
Because people are nervous about a lot of factors, most of the GMO options are not legal to sell for commercial use but they work so well and eliminate so much of the bad stuff that otherwise tends to happen. Papayas and some squashes have had genes from viruses in them since the mid-1990’s and got grandfathered in to the law, which is good for people who eat papayas and squashes, because viruses can be devastating in those crops, and every other GMO that’s been introduced has been withdrawn from the market or never offered. That’s in the US. I guess there are other crops that are GMOs that are legal in China. GMOs are definitely the most workable prospect for virus prevention in some crops (not all the crops, obviously!) but also if no one wants to eat them because people are scared, that’s a pretty big problem.
Um ok! This took a long time and is a long post!
Anonymous said: Melon = King O' Produce? Discuss
I don’t know if the melon is the king o’ produce. Maybe it is because it commands love and because the melons I ate this winter were really good and from Guatemala and Honduras and stuff. Maybe it is not because produce has no king.
Thanks for asking, kiddo.
Maybe you’re reading this blog and thinking to yourself, “Um, shoot! I know that plants can get sick, because I see all your pictures of deformed apples and rotten spots and all. But I don’t think I’ve ever actually EATEN a sick plant!” Maybe you’re a picky produce consumer, and you don’t buy anything fuzzy, or with mushy spots, and you use everything right away so it doesn’t show any symptoms of anything it’s caught. Ok! That’s cool! But what about viruses?
The internet tells me that there are something like 1000 different viruses that we know infect plants. You know what viruses are – they’re little dudes who aren’t alive, they need living cells to replicate themselves, they pump cells full of their own weird genetic goo, they can’t usually be fixed with medicine, etc etc. I don’t know why I’m making this list. You’re not dumb. You know all this. But maybe you didn’t know that even the foods you know from the plants you love can be full of viruses! Maybe your tummy is right now full of plant viruses from eating sick plants. Good thing that these viruses are so host-specific and probably don’t even recognize that you’re a thing.
You’ve had a human-infecting virus before in your own human meat body, right? You know that sometimes your body responds by fighting the virus off, degrading its genetic materials as best as possible, and sometimes your body doesn’t fight it off, so the virus just stays in your body latently. Sometimes you get behavior changes, like fevers and a case of the pukes. Sometimes, according to medicine science (which I know nothing about!!!!), viruses can get into our bodies and help protect us against other diseases, and have generally beneficial effects! Wow!
Plants are like this too! Plants can try to fight off plant viruses, either by directly breaking up viral genetic codes (using RNAi and stuff) or by shutting down infected cells to try to isolate the virus (the hypersensitive response! (remember, a virus can’t survive in a dead cell)). Sometimes plants get infected and don’t respond to the virus and don’t show symptoms. And sometimes plants get sick and get behavioral changes. Unless the viral infection is so bad as to make the produce unmarketable, any of these plants with viruses in them are totally edible by you!
You’ve definitely eaten things that were sick with viruses. For example, sometimes you get spinach that’s really, really crinkly. Maybe it’s sick with a virus! Viruses make spinach do that. Maybe you’re expecting to find a big, tasty, cheap sweet potato at the store, but instead you find a tiny, wood-flavored, expensive sweet potato. It might have been hit with a heavy viral load and have come out all unappealing. And onions get viruses, and zucchinis and all the squashes, and potatoes, and basically so many plants.
Ok! So plants get sick with viruses! And we eat them, and we’re fine!
We can detect viruses in tissue of any living thing using ELISA tests, which are complicated. Sometimes when we test, we find out that a plant has a virus but doesn’t show any symptoms at all, because that plant is tolerant of the virus. Plants can be more than fine too, like when a virus in a tulip plant makes the color break, or when a virus in an apple rootstock makes the scion tree come out small (with a higher fruit:wood ratio, which is a good thing if you’ll remember my rootstock posts). This is such a cool subject to my mind, because it’s a case where we’re obviously working towards plant health for our human goals instead of plant health for the plant. (It’s the nafka mina, if you will!) Usually we want plants to grow up big and strong and make many seeds, which is what the plant wants too, but sometimes we want a plant to grow small and convenient, so we allow it to get viruses, which is probably a metabolic handicap on the “natural” goals of the plant.
Some viruses are pretty bad, though, and we want to protect plants from them. I’m going to talk about three ways we deal with harmful plant viruses in my next post.