Talk about the occurrence and control of common diseases and pests of large-leaved boxwood

Characteristics of the occurrence of major pests and diseases

1. Large-leaved boxwood inchworm: also known as silk cotton wood Venus ruler moth, Wei spear ruler moth, belongs to lepidoptera, ulnar moth family.

Hazard mode: The large-leaved boxwood inchworm is infested by larvae, and is most seriously harmed during the mild climate and abundant rainfall. The larvae feed on the leaves in clusters, and when the leaves are eaten, they nibble on the skin layer of the young branches, resulting in the death of the whole plant. 1 to 3 instar larvae eat leaf flesh to make it mesh-like, 4 to 6-year-old larvae eat a lot of food, initially from the leaf edge to eat, the leaves into a lack of shape of different sizes, severe when the entire leaf is eaten, the larvae spit silk drooping, migration of other branches continue to be harmful, to pupate overwintering, adults flying ability is not strong, with strong phototropism, the large-leaf boxwood tree that has been harmed by the inchworm is extremely poor, and when it is severe, it dies in pieces, which seriously affects its ornamental value.

Prevention and control methods:

(1) Use the phototropism of adult insects to carry out light booby traps during the adult stage;

(2) Pharmaceutical control: the use of Qilin ® to kill net or Qilin ® tree insects once net spray control;

(3) Eradicate egg mass during spawning, turn over the root soil in winter, and kill overwintering pupae;

(4) Wintering adult insects have weak flight power, and are hunted in time during the feathering period.

2. Japanese turtle wax suke: belongs to the homoptera wax borer family.

Hazard mode: the diet is very mixed, strong fertility. The branches and leaves of the affected tree are often densely packed with insect bodies, which can cause early defoliation, tree weakness, and even plant death, and insect secretions can also cause coal pollution disease. Female adults: wax shell gray or slightly fleshy red, oval; male adult: dark brown or brown body, head and thorax dorsal plate is deeper; nymph: wax shell ovoid to oval, slightly raised back.

(1) Strengthen the quarantine of seedlings and scion, eliminate transmission, and strictly implement plant quarantine procedures when purchasing seedlings in different places to prevent the artificial spread of pests.

(2) Pharmaceutical control: use Kilin ® beetle net spray control.

(3) In winter and spring, if the glass nail (that is, the rain song, also known as "tree hanging") can be timely knocked on the branches to shock the overwintering female insects.

(4) Protect natural enemies such as parasitic wasps.

3. Boxwood silk leaf borer: leaf-eating pest

Hazard method: The larvae spit silk to connect the surrounding leaves and young branches to make a temporary nest. It then feeds in it, and in severe cases eats up the leaves, causing the seedlings to die.

(1) Strengthen cultivation management and promote the development of boxwood to increase its ability to resist pests and diseases;

(2) Artificial hunting: During the egg laying period of adult insects, combined with seedling pruning, egg blocks and insect buds are removed and burned in a concentrated manner;

(3) Use black light lamps to booby trap in the adult stage;

(4) When the larvae are seriously harmed, use Qilin ® to hunt and kill net or Qilin ® tree insects to spray and control it once.

4. Powdery mildew of populus macrophylla: Powdery mildew is a common disease in the nursery and green belt of populus macrophyllum, and the leaves of the affected plants show wrinkled deformity, affecting growth. Powdery mildew is mostly distributed on the front of the leaves of boxwood macrophylla, and rarely grows on the back of the leaves.

(1) Proper pruning to enhance permeability;

(2) In the early stage of the disease, the use of Qilin ® Tianjun spray prevention and control, with the plant strong effect is better.

5. Large-leaf boxwood leaf spot disease: when the harm is serious, it causes the boxwood to fall leaves in advance, form bald branches, affect the ornamentation, and even cause death. The disease occurs on new leaves, producing small yellow spots that expand into large irregular spots with bulging edges and broad brown edges. The raised edges have an extended yellow halo on the outside, a yellowish-brown or gray-brown center, and densely covered with small black dots.

(1) Select robust and disease-free seedlings for planting;

(2) The use of Qilin ® Shixun spray control, with the plant strong effect is better;

(3) In winter, the fallen leaves will be removed and burned centrally.

6. Large-leaf boxwood anthrax: water-stained yellow-brown dots appear on the leaves at the beginning of the disease, and then the spots expand, and the onset site is yellow in the later stage, and small black spots appear on the spots.

Prevention and control method: use Qilin ® Shixun spray control, with the plant strong effect is better.