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Perennial rice: Plant once, harvest again and again

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Re: Perennial rice: Plant once, harvest again and again

#31

Post by insane_dreamer »

seifertca wrote: post #14

Perennials are such an intuitively appealing idea but a plant expends a lot of energy ensuring it can make it through the fallow/winter season successfully. Thus perennial cereals only make sense where the cost of seed and planting exceeds the impact on yield. My understanding is even at the theoretical minimum energy needed for most cereals in most growing regions to have a 90% chance of surviving perennially you ne…

> make it through the fallow/winter season successfully

most rice grown by substance farmers is in tropical areas

Re: Perennial rice: Plant once, harvest again and again

#32

Post by ccooffee »

chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

I hadn't heard about rice fields emitting methane before. I was able to quickly find an article, "Methane emissions from global rice fields: Magnitude, spatiotemporal patterns, and environmental controls"[0], which states:

> Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± 0.1 Tg CH4/yr (Avg. ±1 SD) under intermittent irrigation to 38.8 ± 1.0 Tg CH4/yr under continuous flooding in the 2000s, indicating that the magnitude of CH4 emissions from global rice fields is largely dependent on different water schemes.

At 18.3-38.8 Tg CH4/yr, this estimate comes out to about 500-1500 million tons of CO2-equivalent per year according to an EPA GHG-equivalence calculator[1]. Global emissions are estimated at north of 34 billion tons of CO2-equivalent per year[2], putting the total CO2-equivalent from rice fields throughout the world at 1-3% of total global emissions.

Wow.

[0] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/201...

[1] https://www.epa.gov/energy/greenhouse-gas-equivalencies-calc...

[2] https://ourworldindata.org/co2-emissions

Re: Perennial rice: Plant once, harvest again and again

#33

Post by twawaaay »

I know Chinese harvest their rice up to three times a year. I don't see how perennial rice could compete.

Harvesting normal rice is just grabbing entire plants, as many as you can grab at a time. I may know nothing about how harvesting perennial rice is supposed to work, but I grew up as a farmer and I have imagination. You have to leave some part of the plant for it to keep growing crop which means you can't just grab it all. And I think this is a deal breaker.

It just does not make sense to get even more labour intensive plant at a time where labour in all parts of the world that grow rice becomes suddenly so much more expensive.

So until they figure out to build robots that can individually pick rice grains off of a tiny, fragile rice plant, I am not seeing any future for perennial rice.

Re: Perennial rice: Plant once, harvest again and again

#34

Post by NikolaNovak »

ccooffee wrote: post #20
eminence32 wrote: post #3

> They then spent years breeding for the desired traits until they landed on three new perennial varieties to test in the real world Good old-fashioned genetic engineering :)

Well, they've got fancy procedures in there, too: > So what our colleague Duyan Tao did - he, at an early stage, around 10 days after the [by-human-hand] pollination, went in there and dissected out the very young embryo that was developing and put it in tissue culture and gave it nutrients to help it grow. And then he rescued one of these seedlings. And that was the beginning of it. Also, the "old-fashioned genetic…

Arr we saying that cattle today are 4 times the weight of 400yrs ago?

Re: Perennial rice: Plant once, harvest again and again

#35

Post by knodi123 »

melling wrote: post #23
chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

I litter frequently. Some people criticize me for it, but I rightly point out that my own litter is a tiny fraction of city-wide litter, and if I stopped, no one would even notice the difference.

I'm not even the biggest contributor! Mechanized recycling trucks hoist the bins high in the air and let stuff fall into a hopper on the back, and on a windy day, every single bin they pick up produces a few pieces of litter. I don't know why I should change my lifestyle while trucks like that still exist.

Re: Perennial rice: Plant once, harvest again and again

#36

Post by melling »

TheRealPomax wrote: post #26
melling wrote: post #23

Earlier quoted context omitted.

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

Why do people keep pretending that we can only focus on one industry at a time? News flash: WE CAN ADDRESS MORE THAN ONE AT A TIME. What about coal? You tell me, what part of fixing rice production interferes with shutting down coal mining? Because as far as anyone can tell, the answer is not a single part.

We already are seeing climate issues. We could have been off coal by now.

“A 100 years of coal emissions is 1000 years of rice”

By not addressing the big problems sooner, we have shortened the window to seeing significant problems.

We’d have more time to solve the smaller problems, or they may take of themselves. For example, the population in China will drop significantly in this century.

Unfortunately, it sounds like we are lining up our miracles so by 2050, we’ll be at net zero.

Re: Perennial rice: Plant once, harvest again and again

#37

Post by twawaaay »

chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

I am not convinced (I grew up on a farm).

It is usually harder to get rid of any weeds when your crop is growing on the field. After harvest, you just get rid of everything, turn the soil (but I don't know anything about rice farming) and you kinda get a fresh start.

ON THE OTHER HAND, we already have robots that can easily identify weeds with a camera and zap them with lasers or other shit. Which just seems so much more reasonable in the near future than trying to harvest individual rice grains off of a perennial plant that cannot be damaged so that the plant can provide sun cover to prevent weeds... just not seeing it.

Also, Chinese harvests rice up to three times a year. And the harvest itself is much easier if you can grab entire plants. So I am not convinced anybody is going to get interested in it.

Re: Perennial rice: Plant once, harvest again and again

#38

Post by melling »

knodi123 wrote: post #35
melling wrote: post #23

Earlier quoted context omitted.

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

I litter frequently. Some people criticize me for it, but I rightly point out that my own litter is a tiny fraction of city-wide litter, and if I stopped, no one would even notice the difference. I'm not even the biggest contributor! Mechanized recycling trucks hoist the bins high in the air and let stuff fall into a hopper on the back, and on a windy day, every single bin they pick up produces a few pieces of litter…

Nice meaningless analogy.

Let me fix it for you.

“You litter frequently in your neighborhood, while 200 people litter in the park across town. What problem should the town address sooner?”

We are at the brink of too late.

Where did you go wrong?

https://amp.theguardian.com/environment/2023/mar/20/ipcc-cli...

Times up.

Re: Perennial rice: Plant once, harvest again and again

#39

Post by baxtr »

knodi123 wrote: post #35
melling wrote: post #23

Earlier quoted context omitted.

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

I litter frequently. Some people criticize me for it, but I rightly point out that my own litter is a tiny fraction of city-wide litter, and if I stopped, no one would even notice the difference. I'm not even the biggest contributor! Mechanized recycling trucks hoist the bins high in the air and let stuff fall into a hopper on the back, and on a windy day, every single bin they pick up produces a few pieces of litter…

I don’t know where you live, but listen: “Don’t mess with Texas!”

https://www.youtube.com/watch?v=V2qIF3PL7lQ

Re: Perennial rice: Plant once, harvest again and again

#40

Post by samstave »

chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

"Rice is the national dish of the Philippines"

--

A relative who worked in the Philippine government on RICE specifically

His other quote was "we have this department because Rice needs to be on every plate, every meal"

The flooding isnt to prevent weeds, its to prevent INSECTS, and rice is very water tolerant.

---

So, wouldnt it be sane to say that perennial rice in a small growing area would be good.... also, have you ever seen rice drying on tarps on the side of the road?

So in addition to this you also need to account for how the rice is harvested and dried...

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