Defend Your Crop
The sugarcane aphid, Melanaphis sacchari, was discovered late in the 2013 growing season in the coastal sorghum regions of Texas. Public and private crop protection partners have researched and learned a great deal about the pest over the last seven growing seasons, and today farmers are effectively managing the aphid. Occasionally, growers and consultants may refer to the sugarcane aphid as the ‘white aphid’ or ‘SCA’.
Diligence is key, and it is important for producers to scout fields and apply a recommended insecticide when the economic threshold is reached. Sugarcane aphids will only survive and multiply significantly in sorghum genotypes, including Johnsongrass, shattercane, sorghum-sudangrass, sudangrass, forage sorghum and grain sorghum. Sugarcane aphids will not survive on any of the major crops such as corn, cotton, soybeans or wheat. However, sugarcane aphids are distributed by the wind, so small colonies can be found in these crops, but at this time, they have not been found to be of economic importance. The sugarcane aphid that infests sorghum is a different biotype than the sugarcane aphid that is found in sugarcane but they look identical in appearance.
Hybrid Selection for Tolerance/Resistance
Grain Sorghum
Seed companies have now had multiple growing seasons to observe their hybrids and should have a good grasp of their tolerance level to sugarcane aphids. Growers in those regions where sugarcane aphid has been a reoccurring issue should visit with their seed company representative as well as seek advice from regional extension agronomists and entomologists when choosing hybrids.
When choosing a sugarcane aphid tolerant hybrid, all of the criteria used for selecting a non-tolerant hybrid should be considered. Growers are better off to plant a regionally adapted non-tolerant hybrid with good yield potential over a poorly adapted tolerant hybrid. Sugarcane aphid can be controlled with good scouting and timely insecticide application, if needed.
Current commercially available tolerant hybrids are not immune from sugarcane aphid. However, research has consistently shown that sugarcane aphids reproduce slower on tolerant hybrids and in some cases are able to withstand a higher sugarcane aphid population without a reduction in yield compared to susceptible hybrids. Tolerant hybrids should be scouted and an insecticide should be applied once the economic threshold has been reached.
Private companies and university sorghum breeders continue investigating tolerance and resistance. They have identified better sources of sugarcane aphid resistance and tolerance and these qualities are now incorporated into many commercially available hybrids.
Check with your seed company on which of their grain sorghum hybrids are most tolerant to sugarcane aphid. Several companies are now designating their most tolerant hybrids with a brand. For example, Alta Seeds brands their most tolerant hybrids with the APHIX brand.
Forage Sorghum
Unlike grain sorghum, there are only a few forage sorghum hybrids that have sugarcane aphid tolerance. With the exception of these few, at best, all we can say is that certain hybrids are less susceptible than others. On a positive note, companies have been working to incorporate sugarcane aphid tolerance into their forage sorghum, particularly those used for silage. For example, Alta’s ADV F6520, from its EMPYR Premier Forages lineup, has been given the Aphix brand signaling Alta’s ‘best-in-class’ option for SCA tolerance. It is expected that more SCA tolerant silage sorghum hybrids will be introduced to the market over the next couple of years.
In sorghum silage, Texas A&M University research has shown yield can be reduced as much as 40 percent prior to sorghum flowering if a high infestation of SCA occurs and is left uncontrolled. Additionally, quality of the silage is reduced, primarily because of a reduction in starch due to lower grain production. Both silage yield and quality are affected much less if the SCA infestation occurs after the grain milk stage. However, late infestations can produce honey dew in sufficient quantities that could interfere with harvest.
Additional Resources
Aphid Effects
Scouting
- Fields should be scouted once a week for signs of the aphid. Once they are found, begin scouting at least twice a week. Look for small colonies of aphids that are bunched together on the underside of leaves.
- Honeydew buildup on leaves is an obvious sign that can indicate the presence of sugarcane aphid buildup. To determine if an insecticide treatment is needed, note the presence and number of aphids on leaves in at least four areas of the field.
- In each area of the field examined, collect a leaf from the bottom and top of 20 plants, and observe the presence and number of aphids.
Sugarcane Aphid Scouting and Detection in Sorghum
Source: Texas A&M AgriLife Extension
When to Treat
Insecticides
Insecticide Application
Beneficial Insects
Harvest Considerations
Video Series
Below are seven videos that are part of our sugarcane aphid management series. In the videos, Sorghum Checkoff agronomist Brent Bean, Ph.D., summarizes the research findings into best management practices and next steps for growers.
Texas A&M AgriLife Extension: SCA Identification and Estimating SCA Numbers
Play VideoInformation provided by the United Sorghum Checkoff Program