Aphid disease of oleander

Morphological characteristics: aphids belong to Homoptera, Aphididae, wingless parthenogenetic aphids: body length 2.3mm, wide 1.2mm, oval, yellow body, obvious markings in the eighth ventral segment. There are obvious reticulation on the body surface. The middle frontal tumor is raised. The top is flat; the antennae are tiled, with a body length of 2 to 3. The ventral tube is long tube-shaped, the tail is tongue-shaped, hanging in the middle, and there are 11-14 long curly hairs on it. Winged parthenogenetic aphids: body length 2.1mm, wide 1.Omm, long ovate; head and chest black; antennae are body length 3 big 4. There are small marginal tumors in segments 2-4 of the abdomen, and the abdominal canal is long cylindrical.

Damage to oleander and yellow oleander, adult and nymph aphids gather on tender leaves and shoots to suck juice, often covered with tender shoots of 10-15cm, resulting in leaf curling, poor seedling growth, serious impact on new shoot growth, resulting in leaf ossification, stem and leaf death, flower shape becoming smaller or abnormal flowering. The secreted honeydew often sticks to cover the leaves, especially the young leaves. At the same time, the occurrence of coal fouling disease was induced, which seriously hindered the normal development of plants.

Occurrence regularity: more than 20 generations a year, often overwintering with adult nymphs in top shoots, tender leaves and axillary gaps of buds. In the first and middle April of the following year, it began to move slowly, and propagated in the same place to expand the damage. This pest can be seen all the year round, but the number of aphids is the highest from May to June, which is the peak period of reproduction. Wingless parthenogenetic aphids, nymph aphids and winged parthenogenetic aphids were found on the same plant at the same time. Each female aphid could produce about 25-30 nymph aphids on average. When the temperature was high, most aphids lived in shaded places, and wingless adult and nymph aphids overwintering could be seen in the middle and last ten days of November. The aphid has two peak periods in one year, that is, from May to June and from September to October. From July to August, due to the high temperature and the restriction of various natural enemies, the insect population density was low and the harm was reduced. At 20 ℃, it takes 7-8 days to complete a generation. The life span of adult aphids is 15-21 days.

Prevention and control measures:

(a) the adults are caught by nets during the peak period to reduce the source of worms.

B. the leaves with eggs were removed during the spawning period.

C. Spray 5000 times of 50% aldicarb wettable powder, 2.5% nicotinine EC, 2500 times of peach Xiaoling EC, 1000-1500 times of 50% aphid pine EC, and 3000 times of 2.5% kungfu EC.