Several things
1) wrong section, so I'll most likely be moving this thread soon. This is the aeroponic section, thats a soil grow.
2) looks like nute burn, but need more details. Normally the best thing to do in that instance is to flush it. Ie, put it in a sink,make sure it drains good, and keep it under a LIGHT running faucet there for a good hour, maybe longer, need more info. Though, before you do that, it would be best if you said what kind of soil, nutes your using. Also, what kind of lights, the better the light penetration and lumens, the more nutes the plant can use.