LAB #5 GERMINATION AND PRODUCTIVITY

                                   PART 1: Seed Germination

Introduction

The purpose of this lab was to calculate the germination, and total plant growth in heights of the radish of the seeds. Two kinds of treatments were used. One treatment was put with normal light conditions and one treatment of a total darkness. The question on this experiment was: Can plants germinate in the dark? And the Hypothesis was: Seeds do not germinate in the dark. For proof this experiment the students were divided into 4 groups, each group planted 4 seed per cup in 36 for every sample, so the experiment has repetition.

What was our control for this experiment?

The control for this experiment was LIGHT CONTROL, but for proofs the hypothesis was used the dark germination, which consisted to put two tray of 36 samples (6*6). Each sample has 36 cups that were planted with four seeds each one.  One treatment was put in total darkness, and the other in the normal light conditions. Both treatments germinate, but the one that was put in the normal light with better conditions, than the one in the darkness.

What is the percent germination for the LIGHT TREATMENT? For the DARK TREATMENT?

Light treatment

69/144 = 0.479 * 100% = 47.9% = 48%

Dark treatment

50/144=0.347*100%=34.72%    

                                     PART 2: GPP and NPP

Calculate GPP (gross primary production) of the radishes use the following equation NPP + R= GPP.

Plants in the Light                                           plants in the dark

  Weight before dry 11.4g                           Weight before dry 8.9g           
  weight after dry 2.0g                                 weight after dry 1.9g
  Loss 9.4g                                                       Loss 7g                                                                       

 Duration 7min
temperature 400F                                   NPP + R= GPP:

                                                                   2.0g+1.9g=3.9g

PART 3: WRITE UP

What is the difference in appearance in the dark treatment, and the light treatment plants? If there is a difference in appearance, explain why?

Between those two treatments were lot differences, such as: the plants in the light treatment did photosynthesis, the color of the plants in this treatment was dark green, tall, and a lot water in the plant. The plants in the dark treatment had a brownish and yellow color, because those didn’t photosynthesis, a little water in the plant, those didn’t look healthy as the plants in the light treatment.

If there was growth in the dark treatment plants, explain why that growth may have taken place even though light was not reaching the plants?

A plant produces seeds with an embryo inside of it. The embryo is a mini plant inside of the seed with one (monocotyledon) or two (dicotyledon) leafs inside. When the seed germinates the embryo (the leafs go up and the roots go down) breaks the shell of the seed and comes out searching for light. The embryo by having leafs, has a little bit of energy stored (sugar), so the embryo does not need to do photosynthesis to germinate. Once it germinates, if there is no light the chloroplasts that have chlorophyll (what we see green) are not working to do photosynthesis if the plant stays in the dark. That is why the plants in the dark were weak and yellow, and the ones in the light started to do photosynthesis and were stronger and green. (Shadia sources Tropical Ecology)

Graphs of the differences between R, NPP, GPP, between light and dark treatments.

                 

       % of Germination between Light and Dark Treatment

 Comparison on average height (light and dark treatment)

 

  Comparison on dry and wet weight (light and dark treatment)

The question in this experiment was; the plants can grow in the dark?

The final answer for the question is: the plants can grow in darkness place, but those cannot do photosynthesis, and the quality and growth rate are not the same when the plants have enough sun light and do photosynthesis.