"The [nematode breeding] cycle goes on over and over and over through the season,"Dr Smith said.
"Unfortunately, half-ordinary cotton is a better return than a bumper crop of sorghum or wheat."
"When you have back-to-back cotton for a long time, you just get a build-up of other disease-causing organisms."
"It's really hard to get a sacrificial crop in between production crops,"he said.
"The plant just can't cope with all of those antagonists at the one time,"she said.
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