Occurrence and control of diseases and insect pests of Lycium barbarum

Chinese wolfberry is a deciduous shrub of Solanaceae. Its fruit is called Chinese wolfberry, and its root bark is called ground bone bark, which can be used as medicine. Tender stems and leaves make vegetables. It is distributed all over China, mostly wild. The same genus plant Ningxia Lycium barbarum is mostly cultivated, and its fruit is called western Chinese wolfberry or sweet Chinese wolfberry for medicinal purposes, mainly produced in Ningxia, Gansu and Inner Mongolia. Chinese wolfberry has the occurrence of diseases and insect pests in all periods of growth, which causes great economic losses to production. The occurrence and control methods of diseases and insect pests of Lycium barbarum are introduced as follows:

1 disease

1.1 Black Fruit Disease (anthracnose)

It mainly harms green fruits, twigs, leaves, buds, flowers and so on. The green fruit has small black spots or irregular brown spots on the fruit surface at the beginning of the disease. in case of continuous overcast and rain, the disease spots continue to expand, half or the whole fruit blackens, and the fruit shrinks when it is dried. When the humidity is high, many orange-red colloidal spots grow on the diseased fruit. The disease of twig, leaf tip and leaf margin produced brown semicircular spot, which became black after enlargement, wet rot when the humidity was high, and sticky orange spots appeared on the surface of the disease, that is, the conidia disk and conidia of pathogens. Prevention and control measures: trench drainage, removal of diseased fruit. During the result period, 1 ∶ 1 ∶ 100 Bordeaux was sprayed, and 50% Bacterin wettable powder was sprayed immediately after rain. Cut off the diseased branches and fruits in time after harvest, remove the diseased and residual fruits on the tree and on the ground, and concentrate on burying or burning them. The disease and residual fruit on the tree and the ground were removed again before the first rainfall in June, and the source of primary infection was reduced. The pesticide was sprayed once before the first rainfall in June, and an appropriate amount of urea was added to the solution to kill the overwintering pathogen and enhance the disease resistance of the tree. After the onset of the disease, we should focus on spraying after rain, and the spraying time should be carried out within 24 hours after rain to prevent conidia germination and invasion. Flood irrigation is prohibited during the onset of the disease, and stagnant water in Qiyuan is eliminated after rain. Watering should be carried out in the morning to control field humidity and reduce fruit surface dew at night. Timely control of aphids and mites during the onset of the disease to prevent pests from carrying spores to spread diseases and cause wounds. At the beginning of the disease, 75% chlorothalonil wettable powder or 70% mancozeb wettable powder, 64% alum wettable powder, 58% metachlorothalonil manganese zinc wettable powder, 75% chlorothalonil wettable powder 1000 times, 70% mancozeb wettable powder 1000 times, 50% carbendazim wettable powder 1500 times were sprayed. Control every 10 days or so for 2 or 3 times in a row. Stop using medicine 7 days before harvest.

1.2 Root rot

It mainly harms the root and stem base of the plant. The appearance of the diseased plant showed yellowing and drooping leaves. Digging up the diseased plant to examine the root and stem showed that the affected part turned brown to dark brown, and some of the cortex rotted and fell off, exposing xylem. The vascular bundles inside the rhizome also turned brown. White to pink pink mold symptoms sometimes appear on the surface of the affected area when it is damp. The disease occurred in the middle and last ten days of June and was more serious from July to August. At the beginning, the root blackened and gradually rotted, then the aboveground part withered and the whole plant died. Prevention and control measures: rotation is recommended in frequently affected areas, preferably in water and drought rotation. Leveling the land, planting in high beds and deep ditches, lowering the groundwater level, clearing ditches and draining water after rain to prevent the soil from getting too wet. Formula fertilization, increase the application of phosphorus and potassium fertilizer, avoid the application of undermature soil fertilizer. For leaf Lycium barbarum, 1000 times solution of potassium permanganate can be used as fixed root water when cutting. After the cuttings survived, before the occurrence of the disease, the latest after the disease, regular or irregular spraying to prevent and control the disease. In addition to prevention and control with potassium permanganate solution, 20% Kangkuning water agent 600 times solution, or 15% mixed amino acid zinc magnesium water agent 500 times solution. 3-4 times in a row, once every 7-15 days, dense in front and sparse in back, drenched through foot. The roots were irrigated with 50% thiophanate methyl 1000-1500 times or 50% carbendazim 1000-1500 times.

2 insect pests

2.1 fruit fly

Distributed in China, Ningxia and Qinghai. The larvae mainly feed on the fruits of Lycium barbarum and have no medicinal value after being eaten. There are 2 or 3 generations in a year, and the pupa overwinters in the soil. Prevention and control measures: spray 1000 times of 80% dichlorvos EC or 1500 times of 40% dimethoate EC every 7 to 10 days, even 3 times for 4 times; you can also use poisonous soil to eliminate the first emergence of adults in the soil or manually remove maggots.

2.2 aphids

Harm young buds, leaves, young fruit. It happens for many generations in a year. Overwintering with eggs on branches. Generally, Chinese wolfberry began to do harm after germination in April and flourished in May. A large number of adults and nymphs were harmful on shoots and buds. The insect population rate decreased after entering hot summer and increased again after autumn, and the second peak appeared in September. If too much nitrogen fertilizer is applied in production, the growth is too prosperous and the damage is serious. The damage is the most serious from late May to mid-July. Control measures: use 2000 times of dimethoate emulsion, spray once every 7 to 10 days, spray 3 times in a row. Strengthen the management of Qi garden, adopt the technology of formula fertilization, prohibit the application of more nitrogen fertilizer, and water it at the right time. When aphids multiply, 50% aldicarb, Bacillus thuringiensis suspension or 10% Dachong wettable powder are sprayed immediately. Protect and utilize natural enemies, such as ladybugs, lacewings, aphid flies, etc.

2.3 gall mites

Lycium barbarum leaves, flowers, young fruits, tender stems, petals and flower stalks can be damaged, resulting in blue-black raised galls and bends. When the leaves are deformed seriously, the whole plant is weak, the leaves fall off early, and the yield decreases. The insect occurs for many generations in a year. The adults began to lay eggs in the middle and last ten days of April, and then the larvae invaded the tissue, making the tissue deformed and turned into a blue-black nevoid gall, and the new shoots were damaged the following year. Prevention and control measures: pre-occurrence with 40% dimethoate emulsion 1500-2000 times liquid spray control. Remove the branches with galls in time and take them out of the garden for treatment. The overwintering adult mites in the scales and branches of the same year can be controlled with Baume 3 °stone sulfur mixture before overwintering.

2.4 negative mudworm

The leaves of adult larvae showed irregular lacerations or pores, and then residual veins. The lightly injured leaves were polluted by excreta, which affected the growth and fruit. when the leaves and shoots were seriously damaged, the yield and quality were affected. Adults like to live on branches and leaves, laying eggs on the leaves or on the back of the leaves, showing a herringbone shape. The larvae carry their own feces, so they are called negative mud worms. There are three generations in a year, and the harm is the most serious from June to July. Prevention and control measures: from July to August, use 40% dimethoate EC 1500 times 2000 times, or 80% dichlorvos EC 1500 times, spray once every 7 days, 3 times for 5 times.