Managing Russian Wheat Aphid: Pest Management Guidelines for Small Grains
Russian wheat aphids are a severe pest of wheat and small grains in Russia. In hot and dry environments, they are particularly damaging and can result in huge crop losses. RWAs are also known to vector aphid wheat streak mosaic virus, which can further reduce yields.
To get rid of russian wheat aphids, apply Beauveria WP as a biological aphid control in wheat and encourage natural predators like ladybugs and parasitic wasps.
Defining Russian Wheat Aphids Pest
RWAs are tiny green bugs that accumulate on the stalks and foliage of aphid wheat fields. This can make the leaves turn yellow and wither off as these insects suck on the plant sap. However, in serious situations, RWAs may become a cause for destroying whole plantations.
Identifying Aphid Issues
This is usually done by the use of lime-coated, small, green insects that form clusters on the stems/leaves. It feeds on the plant’s sap that makes the leaves dry up. Severe cases of RWAs can cause death in the whole plant.
Characteristics of Russian Wheat Aphids
- Tiny, greenish colored bugs (around 3 mm in size). Russian wheat aphid life cycle has 3 stages: egg, nymph and adult stage.
- Wheat plants cluster on their stems as well as leave.
- Feed on the plant sap
- Distinguish from other cereal aphids by having two tail-like processes at the rear end
Recognizing Signs of Infestation
- Yellowing and wilting leaves
- Stunted plant growth
- Aphids’ honeydew on plants and their leaves and stems.
- Presence of aphids themselves
Impact of Aphid Infestations
RWAs can greatly affect the growth of wheat. In extreme cases, they may even reduce yields to a half. Aphid infestations can also make wheat plants vulnerable to diseases and drought stress.
- Effect on Wheat Crops: RWAs feeding on wheat can do much harm to the crop. In worst cases this might result in a yield loss of up to fifty percent. Aphid infestation can too increase wheat plant vulnerability to diseases and drought stress.
Specific effects of RWAs on wheat include:
Reduced yields: RWAs could cause stunting of wheat and hence, reduction in yields which is achieved through sucking of the sap from the wheat plants. This, in turn, can lead to the suppression of plant growth and a decrease in the amount of grains formed by each of these plants.
Stunted plant growth: The hormonal balance of plants can be disrupted through stunting their growth, thereby creating RWAs. This may cause plants to become more vulnerable to other pests and pathogens.
Increased susceptibility to diseases and drought stress: The susceptibility of wheat plants towards diseases and drought stress is also increased after application of RWAs. Aphids can infect the plant with the pathogens and destroy the plant’s roots system.
- Economic Implications: The wheat growers may experience substantial losses due to Aphid infestation. Wheat producers in the US lost approximately $200m due to RWAs in 2012. This is an instance of how aphids can negatively affect the economy by reducing crop yields.
Wheat management relies on effective aphid control due to health and economic needs. It is through controlling aphids that will allow wheat producers from suffering due to the infestation.
Aphid Management Strategies
Some of the most common methods include:
A. Preventative Measures
There are several steps which can be adopted to minimize attacks by aphids on wheat plants. These include:
- Planting early in the season: Early planted crops are less probable to catch RWAs.
- Planting resistant varieties: Several wheat types have resistance to RWAs. They are some of the varieties that may be planted in order to avoid infestation.
- Controlling weeds: RWAs are also common in weeds . This helps to aphid control in wheat numbers, thereby reducing the chances of their invasion on wheat fields.
B. Biological and chemical control methods
In addition to this, some biochemical control measures can be adopted like if RWAs are identified in wheat crops.
Using natural enemies such as predatory arthropods is one example of biological forms of control. Beneficial insects such as ladybugs, lacewings, and hoverflies are natural predators of aphids.
A second chemical method is applied, whereby insecticides for aphids in wheat are used for killing aphids. Various insecticides can work on the RWAs. Some of the most common ones include:
- Insecticidal soaps and oils: The insecticides suffocate the aphids.
- Systemic insecticides: They are absorbed into the plants and once aphids feed on this plant sap; they end up dying.
Here are some examples of bioinsecticides that can be used to control aphids in wheat:
Monitoring and Early Intervention
Regularly surveil wheat for RWA by detecting aphids and other invasion signs. If you spot these phenomena, enact appropriate interventions to restrict infestation spread.
Implementing Surveillance Techniques
Wheat scouting is necessary for timely control of aphids since it allows tracking RWAs in wheat fields. There are a number of different surveillance techniques that can be used, including:
- Visual inspections: Checking wheat plants often for aphid, an attack, or its existence. It will involve inspecting the stems, leaves, and heads of the plants.
- Yellow sticky traps: Aphids may also be trapped using yellow sticky traps as a means of monitoring. Put traps across the fields and inspect them frequently for aphids.
- Scout fields for aphid hotspots: Aphids may thrive in an area that has a large number of weeds and stresses such as drought. Scout these areas more frequently.
Initiating Timely Aphid Control Actions
Thus, the early detection of RWAs and enacting measures on time, can help in curbing the spread of the infestation. There are a number of aphid control actions that can be taken, including:
- Biological control methods: Free beneficial insects like ladybugs and lacewings that eat aphids.
- Chemical control methods: Use insecticides to kill aphids. The three major insecticides that have been used in the control of RWAs include insecticidal soaps and oils, pyrethroids insecticides, and systemic insecticides.
When choosing an aphid control method, it is important to consider the following factors:
- The severity of the infestation: Chemical controls may be required where there are high aphid population.
- The stage of the wheat crop: Pollination must be protected by all means after the wheat crop flowers and therefore chemical control measures should only be applied prior to this.
- The presence of beneficial insects: Biological controls will therefore only work if in the field there are many beneficial bugs that could help curb harmful pests that can cause diseases to plants or damage them.
Conclusion to Treat Russian Wheat Aphids
RWA is an issue facing wheat farmers. Though, many options exist to control aphids at this point. Growers should adopt effective preventive measures, constant monitoring of production processes, and take quick counteraction towards RWAs.
Summarizing Key Management Strategies
- Earlier plantings, resistant varieties, and weed control.
- Releasing beneficial insects among other biological control methods.
- Insecticidal soaps, oils, as well as systemic insecticides that are used in chemical control.
- The RWA’s presence is always monitored, and actions are taken early on.
References:
- Hatting, Justin L., Stephen P. Wraight, and Ray M. Miller. “Efficacy of Beauveria bassiana (Hyphomycetes) for control of Russian wheat aphid (Homoptera: Aphididae) on resistant wheat under field conditions.” Biocontrol Science and Technology 14.5 (2004): 459-473.
- Wang, Z. G., and G. R. Knudsen. “Effect of Beauveria bassiana (Fungi: Hyphomycetes) on fecundity of the Russian wheat aphid (Homoptera: Aphididae).” Environmental Entomology 22.4 (1993): 874-878.
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