Grass innards

[mrsonchus]

Hi all, I've been looking a lot at various grasses lately and their structure as a clue to their somewhat problematic identification for myself - a complete beginner with grasses. The new stereo 'scope is enabling me to dissect and 'target' tissues within specimens much more accurately before moving them over to processing or examination with the 'big 'scope'...
Anyway I was dissecting a grass-stem longitudinally today and some extremely fine 'hair-like fibrous tissue' snagged on my scalpel from the central core of the stem and I had a quick look at it under the 'scope. It looks like vascular tissue and when stained lightly in water with Safranin turns out to be just that...
To cut a long story short, having stained, squashed and applied a cover-slip some rather nice images came forth and I thought some may like a look at them - I can't tell you much about the tissues I'm afraid, I'm totally new to grass morphology but was quite enamoured with these colourful images and some of the cellular-detail picked out by the Safranin...

Central core in-part - no epidermal tissue etc..

ws_x4_grass_vascular_stem_core_1.jpg (47.88 KiB) Viewed 3862 times

ws_x20_grass_vascular_stem_core_1.jpg (92.15 KiB) Viewed 3862 times

ws_x40_grass_vascular_stem_.jpg (125.27 KiB) Viewed 3862 times

ws_grass-15-07-16-15-26-33.jpg (57.07 KiB) Viewed 3862 times

No doubt - Safranin is a lovely & subtle stain when used with restraint - back to grasses I go!

p.s. sectioning-update, I've just started working in earnest on a replaceable-razor (blade..) fitment for my rocking microtome - I really don't have the inclination to invest time and money into blade-sharpening - I just loath the idea! It's looks to be a real drag the more I look into it...

A quick video of the V1.1 blade-holder in action...


Thing are going well, hopefully the rocking-microtome will be able to use ordinary razor-blades that are also quickly changeable when I finish this project, although I've limited time to spend on it at the moment.

Oh yes, I'm currently also giving serious thought to purchasing a rotary-microtome too - bank-balance permitting... I just love my microscope! Back with some more pictures ASAP - I need to process another batch of paraffin-blocks for the blade tests!
Having loads of fun - great time of year for all things botanical!

[vasselle]

Bonjour.
Superbe photos,elles sont très belles.
Cordialement seb

[apochronaut]

very interesting work and beautiful pictures too. I have looked at insect trachea a little and these could be mistaken for them. Just shows how similar we all are.

[mrsonchus]

very interesting work and beautiful pictures too. I have looked at insect trachea a little and these could be mistaken for them. Just shows how similar we all are.

Thanks apo & seb, I'm pleased you like them.

It's a constant source of amazement how form & function relate to each other. Everything I find when studying plants has a very good reason for being (or perhaps I should refer to it as a function?). I'm on the hunt for sieve-plates at the moment and the 'squash' appears to have potential from what I've been able to glean with the quick look at this grass tissue....

I think I may put some grass specimens into FAA and save their exploration for the dreaded Winter months...
Thanks again for your kind comments both.

[JimT]

How do you put the scale in the images? Very effective. Also very precise.

[gekko]

Superb, beautiful images, the result of excellent work. Color, sharpness, detail, are all excellent. Thank you for sharing! (I hope that you've not abandoned the magazine article project.)

[mrsonchus]

How do you put the scale in the images? Very effective. Also very precise.

Hi Jim, it's pretty easy - you will need to buy a 'stage-micrometer slide' - sounds posh but it's just a slide that has a presumably very accurate series of 'scales' either printed or etched onto it's surface - I'm not sure which but it's irrelevant anyway. This is placed upon your microscope's stage as per any slide and an appropriate set of lines (scale) for your objective is focused upon in the usual way. My stage micrometer has 3 scales on it -
1) a set of lines that are 0.1mm apart (i.e. 100µ) - good for your lower-power objectives e.g. x4
2) a set of lines that are 0.05mm apart (i.e. 50µ) - good for med power e,g, x20
3) a fine set of lines 0.01mm apart (i.e. 10µ) - good for x40 and above in my experience

This set of scales is used together with your microscope-camera software, which will very likely have a facility to put a 'measurement layer' over your images as seen and photographed through your camera. This facility will have a 'calibrate measurements' setting that allows you to do just that.

Each of your objectives need to be calibrated - you'll only need to do it once - the settings for each objective are stored and selectable from within the software.
Essentially, for each objective, you must set your camera-image on screen to 100% during calibration, draw a line of known length on the image using the scales and 'tell the software how long the line is' - that's it - your software will then enable you to put scales, measurements etc onto your images, as seen in my 'grass innards' images.

A tip - a very important one for using measurements:
select a 'zoom-level' or 'focus-setting-position' on your camera and it's optics that you like - I always set mine to parfocality with my microscope's focus - and keep it the same as it was when you calibrated your measurements. If you don't do this, chaos will be the result! Altering this setting alters the image-size and trashes calibration! I have my Toupcam's focusing optics taped in the same position with black tape!

If you have something (perhaps of about 100µ) of a known size - perhaps measured with a micrometer say, you could use this to calibrate your system instead of buying a stage-micrometer (they're about £25)..... maybe..

Sorry this is so brief - to describe in detail the process would take a lot of text! Download the free 'Toupview' software (I use this and it's superb) and do a dummy-run with say a ruler in mm - you can achieve a rough calibration at least and get a feel for the process.

These instructions are for a USB eyepiece plugin-type camera - I haven't calibrated a DSLR and the Toupview software doesn't work with a DSLR as far as I'm aware...

Hope this helps a bit - I can give more specifics if you need them.

[mrsonchus]

Superb, beautiful images, the result of excellent work. Color, sharpness, detail, are all excellent. Thank you for sharing! (I hope that you've not abandoned the magazine article project.)

Hi gekko - thanks very much.

Now then, I'm going to get started on some articles although I've a little less time to spare than anticipated - I think I'll make a start with a general overview of the whole process - this is an area I had trouble grappling with when I started, it all seemed a miscellany of mysterious processes, each of which could be carried out either successfully or with problems in a couple of dozen different ways! When I started it all looked a completely horrific mish-mash that I only barely managed to understand at all. It was thanks to the late great Walter D that I was able to begin to get to grips with the whole subject at all!
The 'get a few supplies together and have a go' approach is in my opinion the very best (i.e. most likely to lead to encouraging & sustaining levels of success along the way for the lone amateur such as myself) for the beginner - It certainly worked for me - I'm vastly more experienced now but still have a default-state of 'bewildered' most days!
The best decision I made was to invest in a good microscope that I could use rather than constantly maintain. Once I had the 'scope sorted it was all-systems-go for me - I was very luck to be able to buy the 'scope and my bank-balance was limping for several months afterwards..

Enough ramblings - I'm boring myself! Look out for a first-try article very soon.

[billbillt]

WOW!.... This is a wonderful and interesting presentation!.... I am glad the disposable blades worked out... You can probably buy 100 blades for what one sharpening would cost... Great job!!..

[mrsonchus]

WOW!.... This is a wonderful and interesting presentation!.... I am glad the disposable blades worked out... You can probably buy 100 blades for what one sharpening would cost... Great job!!..

Thanks bill - I've a touch of optimism regarding the disposable blades - it seems entirely possible (at this stage anyway) to implement - to be free of blade sharpening would be a liberation indeed - not to mention financially beneficial!

Pleased you like the pictures, the more I look at grasses the deeper becomes their mystery! They're also great subjects to place into my 'herbarium' (sounds great - it's actually a wooden, home-made plant-press!) and to save for a rainy day in Winter....