CropLink

After five years in sorghum fields, the sugarcane aphid is firmly established as a permanent pest of this crop.

Fortunately, Southern entomologists have spent nearly that long hunting down sorghum hybrids that show varying levels of resistance to the pest. For a list from Texas A&M AgriLife Extension, visit
bit.ly/2IqPsWa.

These hybrids are not immune to the aphid, so it remains important to scout for infestations.

Still, resistant hybrids show significantly less damage from the sugarcane aphid, largely because populations build much more slowly on them.

Resistant hybrids can also better tolerate higher populations than a susceptible hybrid, which means growers can sometimes adjust the aphid spraying threshold upward from the standard 50-aphids-per-plant level. For a chart of the adjusted standards for resistant or tolerant hybrids, visit bit.ly/2pfiXBl.

Don’t depend on genetic resistance alone, though. Planting early can ensure that sorghum plants are more mature and resilient when the aphid comes calling.

Texas A&M entomologists recommend growers use an insecticide seed treatment, which can provide control of the aphid for around 30 days. For in-season foliar sprays, Bayer’s Sivanto insecticide is available, and Dow’s Transform insecticide has been granted a Section 18 emergency-use exemption for sorghum in a number of Southern states.

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