Sciency

Last you heard, I was waiting for my parasitic worms to increase in numbers so that we had enough to infect our test plants. Well guess what... of the nearly 360 tomato plants we used to house our worms (you can see some on the bottom left of the photo above) only 27 plants were visibly infected!! And this was after about two months of waiting!

We had to infect a thousand Medicago plants with the eggs of these guys, and from what we saw in the past, this was impossible with just 27 infected tomatoes. So I was having a mild panic attack. 

Yet, I still pressed on and hoped for the best... while low key preparing myself for not having a project this year :(

I extracted the nematode worm eggs from the tomatoes using a bleach extraction protocol, which basically involves dissolving the egg sac with diluted bleach to release the eggs into a water solution. Then, got myself comfortable over the dissecting scope to count how many eggs were extracted, and for what I expected to be more disappointment...

But as if the Ecology Gods were smiling down upon me that day... I WAS RICH IN NEMATODE EGGS!!!

Here’s what these eggs look like under the dissecting scope (You have to look carefully but it’s the tic tac looking white dots):

Collectively among the 27 infected tomatoes, there were about 99 613 eggs in the solution! Which meant I could infect the Medicago with about 200 eggs per plant, as we originally expected. 

So we got to work right away. The Medicago seeds were already scarified, germinated, and planted before. The rhizobia culture was also prepared by my partner, which we diluted for inoculation. And now, we had enough nematode eggs to infect our plants. 

(Side note: About half of our Medicago seeds did not germinate, so my partner re-planted a second cohort of plants which are too young to get infected. This means that we only had to inoculate half of our plants for now... we plan to infect all of the plants again, including the younger cohort, this week!)

We spent about 2-3 hours pipetting pre-calculated densities of the bacteria and nematodes onto our Medicago, and thus began the new waiting game. The plants are too young to collect fitness data, so we must wait again for that. 

My main worries now are that I won’t get enough data to do proper analyses for conclusive results before my deadlines arrive in March. I hoped we would have started collecting data wayyy before, but this nematode madness set us back a lot! I am mostly relying on the plant growth data at this point because that’s something we can start collecting right away.

I think those are all the project updates I had to share for now! I will keep you guys posted if more exciting/paralyzingly stressful events takes place soon.

I really appreciate everyone that takes the time to read these and is interested in this stuff!

If you have any questions or comments, I am always happy to chat. 

The sex life of plants may not excite you in a way that human sex would, but we have a lot in common with our green friends than you know!

Like production of sperm and eggs in most animals, flowering plants too have their own eggs, which are found in ovaries, and their own sperm, which comes from pollen (anyone with allergies has encountered these on a personal level... yes we are breathing in plant sperm).

The beautiful flowers we see are the reproductive parts of the plant that contain the male and female components. The pollen hangs on at the tip of a long stem, called a filament, while the ovary is tucked deep into the base of the flower with the only access being a long tube with a wide landing pad, called the style and stigma. Depending on the species and even type of individual plant, it can have both male and female parts, or either one. 

During sex, the pollen of a male reaches the landing pad/stigma of the female, either by wind or through the help of animals (like bees) - this is called pollination - and that’s when the magic begins...

The pollen starts to grow a tube and moves two sperm cells through the tube, down the style, and towards the ovary. Then, one sperm cell fuses with the egg to create the beginnings of new life, and the second sperm fuses with extra bits in the ovary to create endosperm... which is a weird sounding word for things surrounding the embryo that provide it nutrients and other stuff to grow.

Eventually, the ovary around the egg begins to swell and starts producing a protective outer layer, a hard inner layer, and a fleshy, sometimes-sweet middle layer, which we humans know very well as... 

Fruit!

The ovary becomes fruit! Plants have figured out that animals love sweet, high-carb. shit, and used it to their baby-making advantage! It’s a good way to get their seeds out in nice, favorable areas, and be surrounded by rich, fertile poop once the animal disposes the remains from their snack. The seeds (which are developed embryo) don’t get dissolved by stomach acid because they have a strong shell!

The photo on this post is one I took of the tomato plants I’m growing for my project. I noticed that some were flowering, and others were in the process of producing tomato fruit, so it was the perfect time to share how plants fuck (lol) !

Tomatoes are self-fertilizing so their flowers have both male and female parts and use them to make babies. If you guys want to know more about selfing and out-crossing (which is a topic I looooooveeee to talk about), please let me know!

Otherwise, this is all I had to say on plant porn (for now)! I hope you enjoyed this little anecdote. Please don’t forget to like, reblog, and share with your fruit and/or sex loving buddies. Thank you for the support and love for science and plants!

Many studies on animal behaviour have shown that animals can associate conditioned and unconditioned stimuli through training. Pavlov’s dog is the most famous example of this! But Gagliano’s group used peas to show that plants have this ability too!

Plants need food just like animals do, except food for plants is light. And just like foraging animals, plants are able to detect and move towards the light through phototropism. 

These scientists wanted to know if plants can associate this unconditioned stimulus (light) to a neutral conditioned stimulus, wind from a fan, to see if the plants can learn to associate the two positively or negatively. 

And guess what? 

Peas that were trained to associate the two stimuli positively grew towards the wind even without any light, and peas trained to negatively associate the two grew away from the wind! 

The group also found that this association was only made during the day, because that is when light is normally present for the plants. This shows that plants can learn based on their circadian cycle (yes, plants have them too!) to optimize food intake.

This is not only super cool information, but can actually help us understand more about how plants can survive and evolve under harsh, low light conditions. It opens up new doors for research in physiology and mechanisms allowing this sort of associative learning in plants, which also may not be too different from animals.

If this doesn’t spark your interest in plants, I don’t know what will! 

Plants are cool.

- P

Credits

Image: https://www.flickr.com/photos/rneches/2081938105

Yes, it is a bit dramatic, but with the ever growing concern of unsustainable agriculture, a group of researchers from Zurich have thought long and hard about the possibility!

The group, led by S. Franz Bender, argue that integrating a large diversity and complex community of soil microbiota into crop systems can help mitigate the damage of harsh agricultural practices. They explain that the ability of soil bacteria, fungi, and insects to provide “services” to the plants, such as converting soil compounds into accessible nutrients and recycling nutrients back into the soil, can be used in large-scale farming for sustainable crop production. They also mention that species quantity is not the only important factor, but the type of species and their roles in the soil can also impact effective crop production.

Although this idea sounds promising, some in the scientific community were not entirely convinced. A response to the paper by Anderson A.S. Machado and colleagues from Berlin argue that introducing a diverse group of soil organisms to controlled agricultural systems can have negative consequences. Their main concerns involved potential health risks for humans in terms of release of compounds by some microorganisms, and environmental concerns such as eutrophication.

From my perspective, both papers argue their sides effectively and they ignite the path for much needed research in the idea of “ecological engineering”. They both show that there are significant gaps in knowledge in terms of community-level ecology, and potential evolutionary consequences of introducing naturally occurring soil organisms to extensively genetically modified crops. From my knowledge, microorganisms and plants have genotype x genotype interactions, meaning there is a genetic basis to their interactions, which can also have an impact of this idea.

Nonetheless, I am sure we can all agree that no idea is a bad idea when it comes to preventing our progeny from going hungry. Perhaps our little friends in the dirt will end up saving the world!

HEY! I hope you enjoyed reading this blog as much as I enjoyed writing it. If you are interested and have the time, definitely read through the two papers I talk about, they really made me think!

As always, please reblog and share this post for others to check out. And PLEASE follow my blog for more! 

- P

Sources:

Bender, S. F., Wagg, C., & van der Heijden, M. G. (2016). An Underground Revolution: Biodiversity and Soil Ecological Engineering for Agricultural Sustainability. Trends in ecology & evolution, 31(6), 440-452.