The results of my germination and emergence experiment

26 June

During the past 6 months I have been involved in my own investigation on the effects of temperature on seed germination and plant establishment. In a previous field trial of beetroot only 50% of the plants emerged and it was thought this was due to several hot days. The question arose of whether this was due to the high temperature reducing germination or if seedlings were able to draw up enough water from the soil for transpiration. My experiment showed that although a temperature spike increased the rate of plant emergence, and a temperature drop slowed down emergence, neither affected the total emerged. As a concurrent experiment I investigated how the amount of soil moisture affected germination and emergence. I discovered the less the soil moisture percentage the less the germination rate.

Back in Wellington

19-20 June

 

We had our last set of curriculum focus days. We focused on the capability of ‘critiquing evidence’. Mostly it means you need to repeat or replicate experiments so you can gather enough data to come out with a representative average. It also means you have to look at a range of data to look for abnormalities, as it may mean the method wasn’t done correctly.

 

We also looked at a bit of transition back to school ideas. One of the tutors was away so we had Michael Fenton as a guest tutor. He used to do this programme but now he runs the open polytech science teaching diploma course. As he said, they gave us seeds of ideas, a bit of a look-see into several ideas. One of the ideas was a science table of curious objects.

our science table of curiosities

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a test of the power of air!
...and the strength of balloons?

 

What is the most impactful science we can do?

18 June 

 

I read on the i-plant site a quote from the Chief Operating Officer:  “The most impactful science we can do is that which cares for the environment, reduces waste and improves the wellness of consumers through high quality, safe and healthy food.” I think this nicely sums up the goal of all Plant and Food Research.

Layers of onions...

11-16 June

Today I cut, labelled and weighed 505 onion skin samples. There are 5 plots, for each plot I chose 10 onions to take 4 core samples of the brown skin. Each sample then was separated into the skin’s layers. Each layer was separated into a patty tin with a label.  I then weighed them. Their weights ranged from 0.2g to 0.0088g depending if I could separate the layers.

 

After I had recorded all the fresh weights the samples were put into the oven for 24 hours to dry. Then each skin was weighed again to find out the dry weight.

 

Unfortunately when I went to take the onions out of the oven I noticed some of the layers separating so instead of one sample I now had 2 or 3 or in one case 6 samples!

 

 

Altogether I weighed 634 dried skin samples.

So how many of the original fresh samples separated into more layers?

Why was I doing this? It’s an ongoing experiment looking at quality of onions. In this case they are looking at the quality of the skins.

Taking a core sample

weigh each layer of the sample

label each layer of each sample

put the samples into the oven and weigh once dried

4 samples were collected from each onion

the dried onion skins

 

Beetroot Single vs Double Germination

10 April - 13 June

I have discovered that some beetroot seeds will provide two plants from one seed. I wonder if they grow as well as seeds that only provide one seed.

Hmm.. time for another experiment.

First I had to germinate enough beetroot seeds to collect at 15 doubles. Then I planted them in pots in a cross formation, with the centre being the double and the edges being singles. This is to simulate their growth in the field with other beetroot.

I also planted 15 singles in the same way. So, in all I now had 30 pots - enough replication to give a fair result.

Now to wait for them to start growing.

Germinating the seeds

First emergence

Counting the number of true leaves to record leaf emegence

Measuring the length of the same true leaf each week to record growth

A double...the pink mark the leafs I am measuring

A single

Uh oh! The leaves are changing colour.

Turns out that the leaves change colour like this when they are too cold, too dark and too wet.

 

Bring on summer!!!

 

 



Once I have enough data collected I will compare their growth. Hopefully before all the leaves reach their senescence (die).

Meeting up with Ellie (another teacher fellow)

9 May

Today I went to Ocean Beach to catch up with Ellie. She is another teacher fellow from Christchurch. She is studying Pingao plants in the sand dunes. I thought I could give her a hand then take her into Havelock North and maybe show her here at PFR.

She was with a Masters student that she had been working with at Lincoln. He was looking at analysing the terrain using a drone service to give a 2D visual representation. He had a GPS device and an incline measurer, which he could use as well at ground level. From what he was recording on the ground and what the drone gave he should be able to give an accurate 3D image.

When I joined them they told me they were looking for Katipo spider. I always thought they lived in drift wood and not here. But I was proven wrong. Ellie and Mike had mapped out a 200m x 5m transection from the beach inland. Then they recorded the plant life with GPS coordinates and measured the height, width and depth of each plant, whether they were a single plant or a group of plants, and the incline of the sand dune. They only did this for a 5x5m plot. This became a representation of the whole transaction. Once that was done they then checked every plant for katipo spider, recording each one they found with their sex, their plant host details, their web structure, and their GPS location. They weren’t finding many but they were definitely finding some. In their first transect they found 6 katipo. 

Marking out the transection.

Recording all the plants living in a 5m square.
While Mike measures the size of the plants and the incline of the land,
Ellie uses a GPS unit to record its location.

Then its time to sit down and search in the plants for Katipo spiders.

Can you see the web? Somewhere in this photo is a spider. I can't find it. Can you?

 

Sometimes something else is found. This caterpillar has a horn. Any idea why?

Later in the afternoon I brought Ellie into PFR for a mini tour. She was amazed at how much was happening in plant research.

The next curriculum days

15 -16 April

The second curriculum courses were held in Wellington over these two days. It was also opportunity to catch up with the other science fellows to see how they were going.

The first day we spent the morning looking at the first science capability of ‘using evidence’ and unpacking what this means and how to teach it. We made balloon racers, and then tested them. We were able to observe each other’s cars and take some of their successful ideas and incorporate them into our adapted design. This was using evidence we see from their success.

We did three activities based on the sun. One was looking for places where UV wasn’t present by using UV beads.. The next activity was using a model of an earth and sun (lamp) to look at seasons. The last activity was using an OHP as the sun and a model of the moon. We were the earth and turned ourselves while holding the moon, in the light of the sun, to look at phases of the moon. The ‘using evidence’ for these activities was prior knowledge and testing ideas.

In the afternoon some of the fellows shared activities they had prepared around the context Planet Earth and Beyond, and using the capability of Using Evidence. The other fellows rotated around the activities and at the end they gave feedback and feed forward for each activity. My activity was a game called “Rock”. The participants put a rock on each square of the 4x4 grid, and then they read out clue cards and put a counter of their colour on a rock square that matched the description. When someone had 4 counters in a row they called out “ROCK!” to win. The ‘using evidence’ for this activity was using the cards as the evidence to identify the rocks.

There were other activities such as air pressure in balloons, reading temperature graphs to answer questions, making sink holes, making clouds in bottles, making geysers, and water pressure. I now have plenty of PEB activities to use for exploring the capability of ‘using evidence’.

The last activity took us to Te Papa where we had to find the evidence that showed the link between volcanoes and earthquakes.

The second day we spent some time looking at online resources and planning.

 

Making a geyser

Making a cloud in a bottle

Making a cloud in a jar.

Making a bottle rockets.

 

Recycling

The soil I have been using for my germination comes from Ohakune as it is 'good' soil, without any weeds or contaminants in it. Unfortunately we have a limited supply here so I need to recycle the soil I use. This involves picking out the plants and seeds and drying the soil in an oven overnight to kill off any lingering seeds. Then I can use it again for the next experiment.

A lot of things are recycled here a PFR; containers, paper, labels, string, tins...

Harvesting the humble beetroot

There is a lot of data collected when a beetroot sample is collected.

Count the beetroot in the measured sample plot: 50cm across 3 rows.

The roots sometimes have to be washed and dried of excess mud (we don't want to weigh that!)

Weigh and measure each individual root:

 


The dead leaves are separated and weighed.

And the healthy leaves are weighed.



The healthy leaves have their leaf area measured.





The roots are chopped and put into the ovens to dry.

The healthy leaves are also bagged and put into the oven.

When the roots and leaves are dried, they are weighed.

Finally all the data is entered into a spread sheet.

All to be repeated for the next samples collected in 2 weeks from this paddock.
In the meantime other samples are collected and processed from other paddocks.

There's always plenty to do!

New Experiment

10 April

I started a new experiment today. Beetroot seeds sometimes produce two plants off one seed. My experiment is to see if that makes a difference to their growth.

First I germinated 300 hundred seeds to find the double germinators (one seed with two radicles), then in the glasshouse I set up 30 pots with potting mix. Into 15 pots I planted a double germinator in the middle and four single germinators (one seed with one radicle) around the edge in a square. Into the other 15 pots I planted 15 single germinators in the middle of each pot and four other single ones around each one.

I germinated the seeds by putting them between wet paper towels in a plastic bag.



 

I have put them in the glasshouse to grow. Now I wait...

29 April

The  beetroot plants are starting to grow nicely. Some of the plants missing but the others are showing. Over the next few weeks I will collect growth data, such as the number of true leaves in the centre plant (twice a week), and measuring the length of the second true leaf on each plant (once a week). This will hopefully give me some data after several weeks as to growth patterns.

The true leaves are the ones after the initial cotyledon shows.



 

 

6 May

Today I did a true leaf count of the beetroot plants in the glasshouse. I am only counting the middle leaves as they are the ones that are crucial to this experiment. I am trying to see if there is a difference to plant growth according to whether their seed germinated as a single plant or a double plant. However,  I noticed that when I went to count 3 of the single plants they had become doubles, with two plants growing in the middle.. This tells me that the seed grew a second radicle after I planted it.  I did need to get clarification that the leaves I was counting were true leaves and not the plant’s cotyledon. Most of the plants had 2 leaves so far. I will count again on Friday.

One pot has a very slow growing centre plant. Can you see it?

I use a ruler to measure the second true leaf.

So I know which leaf I will measure I have put a pink tab on its stalk.

 Any experiment with plants takes time for the growth to happen. So a plant scientist will often have several experiments running at the same time.