The latest course of techniques and methods for Disease and Pest Control of Cornus officinalis

Cornus officinalis is a kind of medicine that has been introduced and cultivated in Sichuan. The main diseases that harm Cornus officinalis are anthracnose, angular spot, gray plaster, and so on. The main pests that harm Cornus officinalis are green-tailed silkworm moth, big coir moth, dogwood fruit moth, yellow thorn moth, wood inchworm, green-legged locust, big green leafhopper, small green leafhopper, spot wax cicada and so on. Let's take a look!

Anthrax

[hazard characteristics] anthrax is also known as black spot, black fruit, black scar dysentery. Young fruit disease (fruit anthrax), mostly invade from the top of the fruit, the disease spot extends downward from the top of the fruit, the disease part is black, the edge is reddish brown, the disease spot gradually extends to the whole fruit, the fruit blackens and shrinks, and does not fall off. The results showed that the disease spot was brown and red at the beginning, and gradually expanded into round or oval black sunken spot, with reddish brown edge and red halo on the periphery. The pathogen invaded the leaves (leaf anthrax). It was a reddish-brown dot at first, and then expanded into a brown round spot with a diameter of about 1mm. The edge of the spot was reddish brown, and there was a faded halo on the periphery, and the spot often perforated and fell off. The peak period of fruit anthracnose is from June to August, and that of leaf anthracnose is from May to June.

[control methods] choose sandy loam with deep soil layer and good drainage, not too dense, strengthen management, apply less nitrogen fertilizer and more phosphorus and potassium fertilizer during disease period, promote plant health, improve plant disease resistance and reduce harm. Remove fallen leaves, deep burying or burning of diseased fruits, and reduce the source of infection. At the initial stage of the disease, 1 ∶ 2 ∶ Bordeaux solution was sprayed.

Angular spot disease

[hazard characteristics] Corner spot mainly harms leaves and fruits. Leaf disease, the initial leaf front appeared dark purplish red spots, the edge of the spot is not obvious, only epidermal cell discoloration, leaf back asymptomatic, fruit disease, for rust brown round spots, diameter of about 1 mm, when the number of disease spots is large, connected into pieces, so that the top part of the fruit into rust brown, only damage the peel, the disease spot does not go deep into the pulp. The disease occurred from May to the end of October, and the peak of the disease was in July.

[control methods] strengthen seedling management, interplant leguminous plants, reduce damage, remove diseased leaves, ventilate and penetrate light, reduce infection sources, increase application of phosphorus and potassium fertilizer and farm manure, and improve plant disease resistance. In May, the crown was sprayed with 1 ∶ 2 ∶ Bordeaux liquid protective agent, once every 10 to 15 days, 3 times in a row, or 50% wettable bacilli 800 × 1000 times.

Grey plaster disease

[hazard characteristics] Grey plaster disease generally occurs on the trunk or branch of an old tree for more than 20 years, and the disease spot is affixed to the branch to form an irregular thick film, like a plaster, so it is called plaster disease. The disease is serious when the soil is poor, the drainage is poor, the soil moisture is high, the ventilation and light transmission is poor, and the plant growth is weak.

[prevention and control measures] strengthen maintenance and management, adjust the density of trees, remove the weak and stay strong, remove the small and stay strong, adjust the light conditions, improve the disease resistance of plants, prune the diseased old plants reasonably, remove the diseased old branches, renew the plants, retain the growing branches from the inner chamber, gradually replace the diseased and heavy branches, reduce the source of pathogens, scrape off the mycelium film with a knife, and apply Baume 5 degree limestone sulfur mixture or lime milk to the diseased part. During the occurrence period of concomitant bacteria, 1000 times EC of dichlorvos was sprayed on the tree crown to control the disease. At the initial stage of the disease, Bordeaux solution of 1 ∶ 1 ∶ was sprayed once every 10 to 14 days for many times.

Big green-tailed silkworm moth

[hazard characteristics] the green-tailed silkworm moth is also known as the water green moth, the swallow tail moth and the big green worm. The larvae feed on the leaves, resulting in translucent spots, holes and lacerations, and in severe cases, the whole leaves can be eaten up, and the older larvae can also eat the petiole, which has a great influence on the normal growth, yield and quality of Cornus officinalis. It often occurs from mid-May to early October.

[control methods] Medicinal trees of Cornus officinalis should avoid mixed planting with other forest medicinal materials such as maple poplar, elm, walnut or Eucommia ulmoides, peony, peony, etc., in order to facilitate management and control. During the occurrence of adults, black light is used to trap and kill. 90% crystal trichlorfon 800 times liquid spray can be used at the initial stage of the disease, and artificial egg picking or larva capture can be used in the peak spawning period or larval peak period.

Spodoptera litura

[hazard characteristics] Spodoptera litura is also known as Spodoptera litura, dermatophore, debt evasion moth, marsupial and cloth bagworm. The larvae mainly feed on leaves and can also damage twigs and young fruits. When eating leaves, they can be bitten into holes and holes, and even eat up the leaves and only branches, which seriously affect the flowering and fruiting and the growth of medicinal materials. In August and September, the larvae entered the stage of overeating in the elderly, and the harm was serious.

[control methods] artificial removal of insect cysts, spraying 800-1000 times of 90% crystal trichlorfon in the peak stage of larvae, paying attention to protecting various parasitic and predatory natural enemies in larval and pupa stage, birds, parasitoids, parasitic flies, etc.

Dogwood fruit moth

[hazard characteristics] Fruit moth of Cornus officinalis is also known as stone jujube worm, dogwood flesh worm and medicinal jujube worm. The larvae eat the pulp into vertical and horizontal insect channels in the fruit, and the empty fruit is filled with insect dung, and its harm is aggravated with the fruit ripening. From late September to early October, fruit ripening is the peak period of damage.

[control methods] timely removal of early fruit drop, timely harvest when the fruit is ripe, can reduce the population number of overwintering insects, and 2.5% trichlorfon powder can be used to treat the soil around the tree trunk to kill pupae and larvae.