The members of my groupe made a mixed
hormone square with shoot tips and stems of Chrysanthemum. We used different
amounts of auxin (IBA) and cytokinin (BAP) in 16 plastic boxes to see what
effects different hormone combinations can have.
Auxin (IBA) is known to cause root and
callus formation by high concentration and shoot formation by low
concentration.
Cytokinin (BAP) is more or less the other
way around. It causes shoot formation by
high concentration and root or callus formation by low concentration.
IBA→ ; BAP ↓
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0 ml
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0.03 ml
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0.3 ml
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3 ml
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0 ml
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1
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2
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3
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4
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0.03 ml
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5
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6
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7
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8
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0.3 ml
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9
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10
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11
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12
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3 ml
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13
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14
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15
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16
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Nr. 1 : I
could not get a good picture from of this box because of the condensation on
the inside of the lid. That is why I took a picture of the bottom of the box.
The white lines are the thin roots in the medium. We added neither auxin nor
cytokinin in this box. Although we did
not add any hormones, the plant cuttings built roots. There are two
possibilities for this; the plant cuttings could produce the hormones needed
for direct root formation themselves or we did not work enough systematic and
added hormones into the wrong media.
Nr.
4 : To this box we added 3ml of auxin and no cytokinin. Now there are lots
of shoots and they are thicker and shorter than in box Nr.1.
In the second row the plants already made little calluses
and in box Nr.8 there are callus and roots at the same time.
In the third row the plant parts show callus formation and
no roots. Nr. 9 just shows very little callus compared to the other boxes of
this row.
Nr.
13: We added no auxin and 3ml of cytokinin in this box. There is now a lot
of callus visible.
Nr.
16: We added 3ml of auxin and cytokinin to the media of this box. The plant
parts show lots of callus.
In general, I can say that the expected
effects of IBA and BAP are also true for my own experiment. In the first row
(Nr. 1 to 4) occurred no callus formation. The further down the rows or the
more BAP added to the media, the more callus was built.
In addition, there are more leaves the
further to the right or the more IBA added in the square. I can’t tell if that
is just because of the hormones we added or because the plant parts didn’t have
all the same quantity when we transplanted them into the hormone square.




Dear Barbara,
AntwortenLöschenTrue that there are some differences in the way we interpreted the development. But it's mainly that there were no roots in Nr. 1 and 2 at the early time when I checked the cultures.
What is interesting is that you already saw that in Nr. 4 the root ramification was much more intense than in lower auxin concentration. (Though you wrote "shoots" and I think you meant "roots") At the state you took the picture, the explants in Nr.4 would have already been ready for transfering into soil, I think.
You did a nice job in making the table yourself and writing the number of the container to the photo...
Kind regards,
Juliana
Hello Barbara
AntwortenLöschenNice Job, I have nothing really to add except to give you a comliment:)
Cheers, Marc
Hi Barbara
AntwortenLöschenyou critically reviewed the visible results of your horm-attempt. Your presumption not to have added some hormones in the right container seems to be improbable.
Cheers
Hansruedi