Week 6

Thursday
March 20, 2008
1:00 p.m. - 4:00 p.m.

This week I only had time to check the status of the light exclusion experiments. For each treatment, I recorded how many bulbs had rotted and anything unusual about the bulbs. Then I rinsed the sand off of each bulb and dried them on a paper towel. I measured the diameter and length of each bulb and found the average diameter and length for each group. Then I weighed each group.

I dug up the pot outside and brought it inside so I could observe the bulbs. None of the bulbs outside had rotted, and all of the bulbs had developed thick roots. Six of the bulbs appeared to have the same blue mold that the cold treatment had, and five of the bulbs had developed a white hairy mold. The same blue mold seemed to be in a layer around the bulbs in the bottom of the pot (the bottom 7 cm) but not the upper portion.

None of the bulbs from the greenhouse had rotted, and all but one of the bulbs had developed thick roots. Six of the bulbs were spotted by a red mold. The same red mold seemed to be in a layer around the bulbs in the bottom of the pot (the bottom 7 cm) but not the upper portion.

Seven bulbs from the heat treatment had rotted, and a layer of white mold had formed on surface of the sand. But there was no mold on any of the remaining bulbs, but none had developed any roots. I scrubbed out the pot and changed the sand before replacing the bulbs.

One bulb from the cold treatment group had rotted. Seven of the remaining bulbs had areas covered in a blue mold. The same blue mold seemed to be in a layer around the bulbs in the bottom of the pot (the bottom 7 cm) but not the upper portion. All nine bulbs had short roots.

I lightly watered each of the treatments that I had checked, but none of the four that I had not checked.

I recorded the highest and lowest temperature outside and in the greenhouse for each day the previous week. I then recorded the time the sun rose -6:45 a.m. - and set - 6:45 p.m. (which does not feel correct, but that is what the computer said) - and adjusted the light time for the growth chambers accordingly.

Dr. McFarland explained to me the reason why many of the bulbs had increased in weight and size was because they had absorbed water. He explained that it was not because of carbon, because the bulbs were not photosynthesizing! (they have not yet emerged from the sand) He went on to explain that the plants that will not be exposed to light will not be able to photosynthesize, which I took to mean that their growth will plateau as the plants that are not covered will skyrocket in growth.




The sand was rinsed off the bulbs and the bulbs were placed on a paper towel to dry.

The diameter was measured.

The length was measured.

The weight was measured.

Some bulbs in the cold treatment and the outdoor treatment had a blue mold.

Some bulbs from the greenhouse had a red mold.

Some bulbs from outside had a white hairy mold.

The heat treatment was covered with a layer of white mold.