The first 2 photos look like heat blisters. Exactly how close is that light located to the plant leaves? The 3rd and 4th photo looks like a nitrogen deficiency (with the 4th one showing some burning/wilting on the tips). How often are you watering them? The rest of the leaf looks pretty lush, so I would think that it might be overwatering rather than underwatering. The last one looks like a manganese or potassium deficiency. However, I am just sticking with possible nutrient problems and not considering any possible diseases or infections which might be causing these symptoms.
I have downloaded several web site pages with various photos of the different deficiencies. If you give me an e-mail address, I will send you .pdf's of them.
I would suggest trying to back them a bit away from the light source to avoid overheating/blistering the plant and give a dose of plant food with decent nitrogen and potassium it in. If it is a nitrogen or potassium deficiency that's causing the yellow coloration, you should see some improvement with the color within a few days. You have to be patient though and not overdo it with the plant food since it does take some time to take effect on the plant.

Hey thanks for the info! I have moved the light up a bit higher. I suspected it might be the problem even though the blistering didnÂt happen to all the plants that were at the same relation to the light. I guess some plants are more heat tolerant than others. I will drop you a private line for the pdfÂs, IÂd really appreciate them.

Thanks again!
Phil in Alaska

I'm still having troubles like the plants in the first two photos. I don't think they are getting heat blisters since they are the oldest (closest to the bottom) leaves getting them. Slowly the lower leaves get these bumps then the whole branch eventually dries up. I keep cutting off the bad bottoms and they keep growing getting taller and taller but not getting bushy. Any other suggestions?

Thanks!
Phil in Alaska

Could be the plants are getting root bound. If they haven't been repotted lately, try repotting into a larger, but more importantly deeper pot. Place them deeper in so that the new soil covers more of the stem. The stem will send out more roots and help bush out the plants. When planting outside, do the same, cover some of the stem.

I still think they are heat blisters. When I had my plants under my lights, a couple had the same type of damage. I have a feeling that those older leaves were already damaged when they were young but did not show the damage right away. But since the leaves continue to grow and fill out, you are now seeing that damage that happened when they were baby leaves. Even though other plants at a similar height might not have been impacted, those lights are still basically "spot" lights, with the intensity being the greatest towards the center of the bulb and dropping off along the edges, and plants closest to the center of where the lamp enclosure hangs, would get it worse.