Classification and host plants
Species: M. rosae L.
“Phytopathology, agricultural entomology and applied biology” – M.Ferrari, E.Marcon, A.Menta; School edagricole - RCS Libri spa
Host plants: Rose and other rosaceae.
Identification and damage
Macrosiphum rosae is the typical Rose louse; it is widespread everywhere, both in intensive cultivation and in gardens and parks. These aphids are a few mm long, greenish or pink in color depending on the shapes; these can be ather or winged. They normally live in colonies, especially on young shoots and on still closed flower buds.
The damage is determined by the nutrition bites that cause:
- deformation of the shoots, with arrest of their development;
- deformation of the flower buds that do not open or bloom irregularly.
In addition, this aphid produces abundant honeydew that dirties the vegetation, causing both indirect consequences (burns, asphyxiation, the introduction of smoke) and a disfigurement of plants and flowers, with consequent aesthetic and functional damage.
Macrosiphum rosae overwinters as an egg; however, in certain environments or in years with particularly mild winters, adult forms can also be found on plants in winter (parthenogenetic females) which continue the autumn cycle. In any case, the actual infestations begin in late spring and continue throughout the year, with generations overlapping until autumn; sometimes, as already mentioned, the cycle continues until the following year.
Rose aphid - Macrosiphum rosae L. (photo www.plante-doktor.dk)
The fight against Macrosiphum rosae is chemical. The interventions are carried out at the appearance of the infestations; however, in consideration of the numerous natural enemies of this aphid, it is advisable, before carrying out the intervention, to evaluate the actual consistency of the phytophag and the populations of predators / parasitoids. These include:
- Sirphid and Cecidomid Diptera, Ladybug Beetles, Chrysopid Neuroptera, Thrombidid Mites and Aphidid Hymenoptera.
In case of real need, treatments are carried out with specific aficide products. Or you can use medium-broad spectrum products with an aficidal action, such as: Pyrethroids or natural Pyrethrins.
In England, the use of microbiological preparations based on the mushroom Verticillium lecanii is being tested, which demonstrates a certain activity on this and other Aphids.