Elizabeth, I've never used chitin. The amount I'd need + the time and work that it would require to amend all of my 26 raised beds is probably not practical. Also, a couple of people I know did not get very good control with chitin so I didn't bother to try it.
Poulenger is the manufacturer for both Dragonfire and Teracure. (
http://www.poulengerusa.com/) Teracure is not on their website for whatever reason, and you'll need to call them to order it. Also, you'll probably need to come up with the application rate/math on your own as the label instructions are geared toward large-scale applications on turf. (I do have some watering can instructions for a Teracure soil drench saved somewhere if you should need them.) They are friendly enough when I've called, but just keep in mind most of their customers seem to be golf course mgrs and experienced large-scale commercial growers so that is who they are used to working with when it comes to questions and advice. For ~200 plants, I go though about a gallon/month when plants are in, if that helps.
Dragonfire is a similar product as mentioned before. Teracure is sesame oil + molasses + emulsifier, and it costs less. I'm guessing this is because the concentration of sesame oil is lower. The goal with either of these products is to have it in the root zone at all times when temps are 65F or above. This is how they work:
http://www.poulengerusa.com/Dragonfi...ppflyerNEW.pdf
Also, I've been told by Poulenger that you do not want to let either of these products dry on the foliage and if any gets on the foliage it should be immediately rinsed off. So when applying, it should be a soil drench or run through a fertigation tank as opposed to overhead spraying for tomato plants.
Dried molasses - I can easily find 40 or 50 lb bags at most better nurseries in my area, and for about 200 plants, I put down an entire bag along with various other soil amendments before planting. Table sugar can be used as an alternative if you just have a few plants. A rough explanation is that molasses (or sugar) feeds the microorganisms that are hostile to nematodes and that's why it can help. It's also a good all-round soil amendment.
Since you won't be able to find a Teracure label online, I've attached a photo. A Dragonfire label can be found here:
http://www.poulengerusa.com/Dragonfi...ecpp_label.htm