Ahem..yall called? I hate those things.
If you have a raised bed, take it apart, sterilize everything, put a bottom in it, reload. Its a luxurious lifestyle, that raised bed world.
I fight my nema off by tilling in nema killers and trying to sterilize the soil. The thyme oil product from promax huma grow and the monteray(?) pesticide I used this year will probably get me 2\3 thru the season. Over time they crawl back. They do not move far, but those roots have to grow down and help the nema out. Those roots you are showing sure were nice and long. It lets me get a lot of fruitset, but later after the main bulges of produce I start pulling the plants that are in decline. The produce has been hitting. Pickles anyone?