Re: which pigments are in white mustard and what wave length is best.

Caroline,

You have asked two great questions. let me try to address these question one at a time.

What wavelengths of light are best for mustard growth? I am not a mustard expert, but let give you some info on light and plant growth. First, plants are very efficient at harvesting light to drive photosynthesis. Light that is not needed is reflected or it passes through the leaf. Now most leaves are green in color. This is because the green portion of the solar spectrum is reflected off the leave surface. So using green light to affect plant growth may not give you the best results.

Now blue and red light do exert an influence on plant growth. And I would like to add another, far-red light, to this dicussion. These three wavelengths have significant effects on plant stem elongation and flowering. Of these the red and far-red are most significant. When there is more far-red than red then the stem of the plant will elongate at a greater rate. When there is more red than far-red the stem elongation will be inhibited.

If you are doing germination studies you may want to read a very famous paper on light and seed germination. Here is the citation: Borthwick et al. 1952. A reversible photoreaction controlling sedd germination. Proc. Nat. Sci. USA. 38:662-666.

Now as far as what the mauve pigment is you have found. There are many pigments contained in the cells of a plant. Using chromatography will separate these pigments into bands of different colors. As to what your unknown pigment is I do not know. You would need to obtain sample of known plant pigments and run them through your chromatography and compare these results to your mauve pigment results.

Admin note

Have a look at answers already posted:

Re: Plant Developement vs. Spectrum

Re: How is plant growth affected if placed in different types of light