Russian wheat aphid

D. noxia has a variety of effects on the host plant and the subsequent product for which the plant is used. The host plants response to an aphid infestation is a loss of turgor and reduced growth due to water imbalances as the aphid feed on phloem. The aphid also causes reduction in biomass of the whole plant. However, once the aphid is removed the plant quickly recovers absolute growth rate and has increased relative growth. As a result of previous infestation, the recovering plants are more efficient in carbon assimilation that results in increased relative growth rates and compensates for the leaf damages during aphid infestation.[5]

Aphid infestation on wheat also affects the flour that is made from infested wheat plants. Aphid feeding in wheat results in qualitative and quantitative losses in flour yield. Flour derived from aphid infested wheat has a significant negative effect on the gliadin/glutenin ratio which reduces the bread making quality of aphid infested wheat plant flour.[6] However, although it does reduce the quality of flour for bread-making, it is still within acceptable ranges to be usable.[7]

As D. noxia became an invasive species in North America, it is notable that they possess enough endurance to cold temperatures to survive through winter. Aphid populations can overwinter through temperatures between 0 and 5 degrees Celsius. However, temperatures below 10 degrees Celsius will lead to catastrophic decrease in population.[8] In addition to survivability in sub zero temperatures, the aphids are also capable of rapid cold hardiness (RCH) which allows an insect to develop protection against sudden sub freezing temperatures. Moreover, aphids are capable of RCH without any cost to their reproductive capability.[9]

A method to control D. noxia infestation of wheat and barley is through host control. Host control consists of raising crops that possess genes that may contribute to aphid resistance. Research has been conducted to identify the specific genes that can be attributed to aphid resistance and the information marked to assist in breeding aphid resistant strain of wheat or barley. The genes that have been identified so far have been Dn1-Dn9 and Dnx.[10][11] As these genes are marked for selective breeding, it may serve to manage the population of aphids.[10]

Hopper et al.'s research into biological control is based on the non-pest status of D. noxia in Eurasia, its area of origin. It is possible that natural enemies in that area limit the abundance of the aphids, therefore preventing them from becoming pests. Based on the selection of natural enemies of D. noxia in Eurasia, the paper performed a survey of host specificity of different species of parasite from the genus Aphelinus. Although host specificity and range differs from species to species, Aphelinus hordei has a much narrower range that includes D. noxia. The behavior of females of A. hordei oviposition orients the species specificity towards D. noxia. Female A. hordei rarely approaches aphids that are not of the D. noxia variety. Due to this host specificity, the paper suggests that biological control of D. noxia may be viable through A. hordei introduction into the west.[3]

Potassium phosphate was studied as a resistance inducer on wheat plants against D. noxia. It may serve as a method to deal with the population of aphids that have overcome wheat's genetic resistance. The study indicated that potassium phosphate treated plants either a resistant strain or a non-resistant strain both show a decrease in aphid numbers that were feeding. Thus the data suggests treating wheat with potassium phosphate to induce tolerance against D. noxia.[4]