Wilting and reduced vigor due to disrupted water and nutrient uptake.

Interveinal chlorosis (yellowing between the veins of leaves).

Stunted growth and delayed development.

Honeydew excretion, which promotes the growth of sooty mold and other secondary fungi.

Increased susceptibility to root diseases due to stress and secondary infections.

Transmission of plant viruses, leading to potential spread of disease within the crop.

Rhopalosiphum rufiabdominale exhibits both alate (winged) and apterous (wingless) adult forms. The apterous morphs are dark olive-green, measuring approximately 1.4–2.4 mm in length. The alate forms, slightly smaller at around 1.8 mm, possess darker pigmentation—typically brown to black on the head and thorax—and emerge from the soil to disperse and establish new colonies on nearby host plants.

Reproduction is strictly parthenogenetic; males are absent, and all individuals are female. These aphids are viviparous, giving live birth to clonal offspring. Under optimal conditions, nymphs mature in as little as 7–10 days, and adults may live up to 30 days, reproducing continuously. This rapid and prolific reproductive strategy contributes to the rice root aphid’s ability to establish high-density populations in a short period, particularly in controlled environments such as greenhouses or indoor grow operations.

For ID purposes, it is crucial to use wingless adults for identificaiton. Winged adults and nymphs do not always display defining characteristics required for proper ID, look for:

Reddish brown or greenish brown coloring.

Blush-white mealy wax on the sides of the body and forming dorsal cross bands.

If rice root aphids find their way into your growing space, it’s often through infected clones or through outdoor cultivation, as the winged form of the aphid will migrate into your space through open doors, vents, windows, or even on people. Because of this, strong aphid prevention measures are a critical part of any successful Integrated Pest Management (IPM) program.

These strategies include: A thorough inspection of all incoming plant material—especially clones, followed by a quarantine period to monitor for hidden infestations. Consistent scouting and monitoring during this time helps detect early signs of pest presence.

Implementing clean-room protocols, such as requiring staff to change clothing or sanitize footwear before entering the grow area, reduces the risk of accidental transfer. Establishing a formal cleanup procedure for tools, trays, and workspaces further minimizes contamination.

Together, these practices form the foundation of a strong biosecurity plan—protecting your crop from economic loss, reducing the need for reactive treatments, and maintaining a healthy, pest-free growing environment.

For controlling the rice root aphid effectively, entomopathogenic fungus and Chrysopa are two of the most reliable biological solutions available.

Chrysopa, which contains green lacewing larvae (Chrysoperla carnea), is a highly aggressive generalist predator that feeds on all aphid life stages—including adults and nymphs—as well as eggs of other soft-bodied insects. Because Cannabis Aphids tend to cluster and hide in dense plant material, Chrysopa’s active searching behavior makes them ideal for reaching hard-to-spot infestations.

Entomopathogenic fungi such as Beauveria bassiana or Lecanicillium muscarium work by infecting aphids on contact. Once spores attach to the aphid's cuticle, they germinate and penetrate the body, eventually killing the insect from the inside out. These fungi can spread throughout aphid colonies and are especially useful in high-humidity environments where their efficacy is maximized. For best results, apply early at the first signs of aphid presence to catch infestations before they escalate.

Used in combination, entomopathogenic fungus provides and Chrysopa offers a rapid knockdown to the aphids, making them a powerful IPM duo for cannabis growers looking to manage aphids without synthetic chemicals.