Ecological control

Ecological control

Ecological control consists of managing the cultivation environment within or in the immediate vicinity of the plot and adapting cultivation practices.

The objectives of ecological aphid control are to create conditions that limit the intensity of aphid colonization or increase the carrying capacity of natural enemies in order to increase the natural control potential of aphid populations.

Limiting the intensity of colonization

Adapting the crop calendar
The adaptation of the rhythms of cultures can make it possible to escape the phases of colonization. Thus, the damage caused by barley dwarf yellowing (BYDV) is mainly related to aphid transmission in the fall. The delay in sowing dates of winter cereals after the main autumn dispersal phase considerably reduces aphid infestation and consequently the intensity of the disease.
Use trap plants
Aphids can be diverted from the crop to be protected by offering them a more attractive alternative host plant. This strategy is particularly effective if the "trap plant" is a poor host for aphid population development. For example, a reduction in the prevalence of groundnut rosette virus (GVR) has been observed in fields where this crop is associated with beans. The effect seems to be linked to a greater attractiveness of the bean for the vector aphid, Aphis craccivora the cowpea aphid.
Acting on dispersion
Aphid adults are easily carried away by air currents whose near-ground regime is strongly modified by the landscape relief encountered. For example, windbreaks are preferred obstacles and landing areas that limit the dispersal of adults from one plot to another.

Augmenter le contrôle biologique

Green Corridor
Cultivated areas are often characterized by low ground cover density. Many crop auxiliaries are reluctant to travel long distances on bare ground. The establishment of a dense network of permanent cover (grassed strips, hedges) favours the movement of these organisms in the agricultural landscape and maintains large populations, as is the case for beetles for example. Hedges, on the other hand, are barriers to the movement of syrphids, which are aphid predatory diptera.
Habitat complementation
With alternative prey: the presence of hedgerows favours the hosting of populations of phytophagous insects that are not harmful to the crop and consequently increased activity by natural enemies. So when the aphids settle in the crops, the natural enemies in number and on the spot will be more effective.
    A diversified diet: many predatory or parasitoid species feed on aphids in the larval stage and consume pollen in the adult stage such as hoverflies and lacewings. Ladybirds also use pollen as a complementary food source. The installation of flowering strips near the cultivated plots attracts these auxiliaries and provides them with a source of protein that promotes high fertility.
    Safe havens: auxiliaries present day or night activity rhythms, interspersed with rest periods, and seasonal rhythms. The presence of dense vegetation zones such as hedges and slopes facilitates their life and survival.

Modification date : 07 February 2023 | Publication date : 26 May 2011 | Redactor : Evelyne Turpeau, Maurice Hullé, Bernard Chaubet