What's wrong with my tomato seedlings?
Thank you for the question. At first look this seems to indicate a possible cultural problem. It seems most of the damage appears on tips of leaves indicating inadequate water getting to these points. This could be due to either underwatering of overwatering. This could also be true of other leaves that appeared to have wilted at some point. Dry drafts and light watering could be one explanation. What looks like wilting damage can also be related to leaves touching a warm light. A look at the roots could help determine if there may be a problem underground. Watering from the bottom is a good practice to help prevent damping off. Another issue is the purple appearance of the lower leaves that result of inadequate phosphorous or the plants getting cold. Seedlings do not do well at temperatures below 60°F. The problem that is most worrisome is the black tips. This could be a fungal, viral, or bacterial. Diseases can be seed borne, soil borne, or airborne. Saved seed can harbor diseases. Get seeds from a reputable source. A sterile soilless mix should always be used when germinating seeds. You should always disinfect tools, pots, and trays before use. Removal of damaged leaves using sanitized scissors is probably in order as long as you are not denuding the plant. Isolate damaged plants if you suspect disease. Let us know if you have further problems and need additional assistance.
I hope this is helpful,