How to control oleander aphids? Aphid control methods for garden ornamental trees

Distribution and damage The oleander aphid Aphis nerii Boyer de Fonscolombe, also known as the oleander yellow aphid, belongs to the order Homoptera, family Aphididae. It is distributed in Changchun, Shenyang, Baotou, Taiyuan, Ningbo, Guiyang, Urumqi and other places. It pierces and sucks sap from the new shoots and young leaves of oleander plants, affecting normal plant growth and flowering.

Morphological characteristics: wingless female aphid body length 2 mm, body apricot yellow, antennae dark brown, legs black, cauda tongue-shaped, with 11-14 curved hairs. Winged female aphid oval, head and thorax black, abdomen with black markings, wing veins relatively thick. Nymphs are wingless, with a body similar to that of adult aphids.

Life habits: More than 10 generations occur per year, overwintering as nymphs and adults in new shoots, branches and bark cracks. In May-June of the following year, numbers are large and reproduction is fast, with the entire new shoots and young leaves covered with aphids; in hot and rainy seasons, population density decreases. There is another small peak in September-October, and in November, as temperatures drop, they overwinter one after another. In greenhouses in the north, high temperatures favor the reproduction of this aphid.

Integrated control

(1) Strengthen maintenance and management: prune moderately to allow ventilation and light penetration, creating conditions unfavorable for aphid life.

(2) Protect and utilize natural enemies such as aphidid wasps, lacewings and lady beetles. Artificial transfer of natural enemies can also be used to increase natural enemy populations and enhance natural control.

(3) Chemical control: during the damage period, spray with Anna 100 times solution, or 12.5% Bilin 4000 times solution.