How to identify and control navel orange sycamore?
Yasukite is also known as Yasukite and Arrowworm, which occur in Navel Orange producing areas in China.
(1) Symptoms of harm The yastic tipworm mainly harms the leaves, young branches and fruits of the navel orange, and sucks the sap from the back of the leaves and the surface of the fruit by the adult and nymph swarms. The damaged area of the leaves is yellow spots, and when severe, the leaves are twisted and deformed, resulting in leaf curls and dead branches, and the tree is weakened, causing leaf fall and fruit fall, affecting the yield and fruit quality, and inducing coal pollution disease.
(2) Life Habits The yastic tipworm occurs in 3 generations per year in the Gannan region of Jiangxi Province, and female adults and second-instar nymphs overwinter in the leaf back and young shoots. Spawning begins in late April of the following year, with the first generation of nymphs emerging from late April to early May, the second generation of nymphs emerging in early to mid-July, the third generation of nymphs emerging in mid-to-late September, and stopping laying eggs in October when the average daily temperature drops to 17°C.
The spawning period of adults is up to 40-50 days, and the egg period is extremely short, about 1 hour. The first generation of nymphs are mostly on old branches, the second generation of nymphs are mostly on new leaves and some fruits, and most of the third generation of nymphs are on the fruit. The yastic silkworm does not reproduce parthenogenetically and prefers a hidden, warm and humid environment. Orchards with closed tree canopy and poor ventilation and light transmission are badly affected. Females feed scatteredly, and males tend to congregate near the mother.
(3) Prevention and control methods (1) Strengthen insect monitoring and reporting. After the appearance of the first generation of young insects, the development of male young ants on the autumn leaves of last year or the spring shoots of that year should be frequently checked, and when a small number of male insects appear on the back of the "bird-like" 3 white wax filaments, they should be sprayed once in 1-5 days. Before the occurrence of the first generation of hatchlings from late March to early May, spray the drug once every 21-25 days after the appearance of the first hatching bugs, and spray once every 15-20 days. It can also be sprayed once in early to mid-May and once in late May. When there are 10% of the leaves of the overwintering female adults in the autumn shoots last year, or there are 1 small branch group on the tree with obvious insects, or a few branches and leaves are scorched, or when the number of female adult overwintering female adults on the leaves of the autumn shoots last year reaches 15 heads/100 pieces, the agent should be sprayed. (2) Pharmaceutical prevention and control. Spray with 1500 times solution of 40% phosphorus killing emulsion, or 1000 times liquid of 25% quetiphos emulsion, or 800 times liquid of 50% acetyl methylamine phosphorus emulsion. (3) Agricultural prevention and control measures. In winter, the garden is completely cleared, and severe insect branches, dry branches and closed branches are cut down to reduce the source of insects and improve ventilation and light transmission conditions. Spray 8-10x pine alkali mixture, or 95% oil emulsion 60-100 times liquid, before germination in winter and spring shoots to destroy overwintering eggs. (4) Use of natural enemies for prevention and control. The Japanese square-headed beetle, the whole-breasted oligodic ladybird, the Hubei red-spotted lip ladybird, the yass-tip aphid wasp and the flower horn aphid wasp are all natural enemies of the yagus aphid. Attention should be paid to the protection and utilization of natural enemies during the occurrence of 2-3 generations of the yasukite.