The area of the victim initially changes from the stem to black and then expands to bear fruit. The transverse cutting of the fruit indicates that the center of the pulp tissue is dark brown to black, in a wilted state, and then gradually develops around the outer ring, making it appear light brown, which spreads to the skin scales at a later stage, causing the entire fruit to turn black and die.
Prevent burning diseased fruit and reduce the source of infection; do not apply too much nitrogen fertilizer except for proper pruning of branches and leaves before the rainy season and rainy season, after pruning, disinfect the entire garden with 40% Turkdo wettable powder 1000 times solution; in the early stages of young fruits after flowering, the drug should be used immediately. From young fruit to middle fruit stage, the disease is rampant. Therefore, if you find damage to young fruits during this period, or if 1 or 2 fruits are damaged per tree in the early stages, use 40% Tecordox Wettable Powder 1000 in a timely manner. Spray the entire garden with 500 times the liquid or 70% wettable powder of Daxian zinc to prevent the spread of disease.
Black hyphae are visible at the roots of injured plants in a state of injury, milky white hyphae appear under the bark at the bottom of the trunk, and bright red hyphae appear in wet and cold conditions.
The prevention and treatment of root rot is one of the main reasons for the slow development of sugar apple production in South China, and it is not easy to use drugs for prevention and control.
Harmful conditions In the early stages of the disease, the mesophyll tissue of the epidermis on the front and back of the leaf becomes black and forms small black spots. In the later stages, larger black spots are formed. In severe cases, the entire leaf turns yellow, wilts and falls off.
During the pruning process, the diseased leaf is burned or buried in the soil to reduce the source of infection; after pruning, the fungicide is sprayed throughout the garden to protect the pruned wound and kill the pathogenic bacteria remaining on the diseased leaves. Spray 50% of the phenylmycin wettable powder 3000 times liquid, or 70% promethazine wettable powder 400 times liquid during growth, and spray it on the front and back of the leaves. Keep the orchard ventilated, cut off too long branches, unsound branches and overly dense branches and leaves, reduce the micro-humidity between the fruit trees, and avoid creating conditions for fruit trees to develop.
The rhizomes of fruit trees are prone to harmful conditions. In the early days, the leaves on the ground were slightly curled, withered and drooped. The old leaves begin to turn yellow and brown, and the fruit does not ripen.
It is strictly forbidden to ventilate the cut branches and leaves on the root neck of the fruit tree to reduce the occurrence of pathogenic infection; in the early stages of the disease, the loam near the root neck is stripped of sunlight, and the mancozeb wettable powder is used 400 times to irrigate the roots with liquid or spray in the soil near the diameter of the diseased plant lm to prevent the spread of pathogenic bacteria.
In the early stages of the disease, the red mycelium membrane grows locally on the backlit and wet sides of the trunk and spreads above, below, and around the trunk. The leaves are dehydrated and the leaf edges are curled into main veins. If the weather is dry, longitudinal cracks may appear in the affected area. In later stages, the entire trunk is surrounded by mycelium, and the leaves fall off and appear dry.
To prevent and treat summer and autumn, prune branches and leaves as well as slender branches to ventilate the orchard. The older trunk is damaged locally, cut off the affected area in time, and apply 50% carbendazim wettable powder to the affected area 100 to 200 times. If the pathogen has spread to the entire trunk or branches of the tree, it must be cut down and burned; after summer pruning, if the initial symptoms are found, spray once with 750% 50% carbendazim wettable powder.
In addition, there are anthrax, branch fruit disease, acid rot, white sclerotium, blight, etc., which can be controlled according to the occurrence of the disease with corresponding agents.
Lychee wood beetle moth and acacia wood beetle moth The Lychee wood beetle moth and the acacia wood beetle moth are both pests of the Lepidoptera wood beetle moth.
For harmful larvae, they will dig holes in branches and trunks to form tunnels. They ate the phloem of the branches and formed a tunnel of worms and feces on the outside of the trunk. The larvae hide in the tunnel during the day and go out along the tunnel at night to eat the bark. When the damage is severe, it can lead to the death of young trees.
Control During the incubation period of the larvae, that is, from May to early June, spray 1 or 2 times 90% dimethoate crystal 500 times liquid or 20% Tianniu Ling Emulsion 250 times liquid for control. For larvae that have been swallowed by the trunk, use a cotton cloth dipped in 80% dichlorvos emulsion 100 times the liquid to block the tunnel to kill it.
The damage was severe from June to August and from November to December. The larvae eat fruit, and damaged fruit partially darkens and dries out in the early stages. In a lighter, the fruit deforms and turns black. More seriously, the damaged part extends throughout the fruit, causing the fruit to change from black to dry and stiff, but still remains on the tree.
Control Every year from mid to late June to early November, in the peak of bore egg hatching, the larvae are sprayed before the bore fruit is not mothed, that is, after the flowers fall, the young fruit is about 2 cm in diameter, sprayed once every 10 days, sprayed 3 times. The agent has 2.5% cypermethrin emulsion 1 500 times liquid, 50% borer thiophos emulsion 1000 times liquid, or 25% poison killing wettable powder 1000 times liquid, etc.; from August to December, if the spot borer is infested, 20% cypermethrin emulsion 2000 times liquid or 2.5% cypermethrin emulsion 2000 times liquid, 90% crystal enemy insect 1000 times liquid and so on can be sprayed throughout the park. This insect is a new record species in Taiwan.
Citrus fruit flies are pests of the family Dipterae.
Adults in harmful conditions lay eggs in the host fruit, and the hatched larvae are harmful fruits. Damaged fruit turns yellow when immature, causing fruit to fall and fruit to rot, which has a great impact on the yield and quality of the fruit.
Control During adult occurrence, spray canopy and canopy subsoil with 90% dichlorvos crystal 800 times liquid or 2.5% quinoline sulfur emulsion 500 times liquid to protect the fruit, kill the emerging adult worms and inhibit adult spawning. In addition, toxic methyl eugenol trap cages can also be hung to attract and poison adults. The worm is found in Guangdong, Guangxi, Fujian, Sichuan and Taiwan.
Star beetles are pests of the Coleoptera family.
Damage condition larvae destroy the trunk and main branches, affect the spread of water and nutrients, make adult plants yellow, some leaves fall off, the vitality of trees weakens, and when severe, the entire plant will die.
To control the larval incubation period from June to July, 25% Tianniu Ling Emulsion 250 times or 25% Quethion Emulsion 500 times the trunk.
Beetles are pests of the Family of Scarab beetles of the Order Coleoptera.
Harmful conditions can severely damage new shoots, leaves and flower nails. Adults congregate in and around the orchard during the day and feed on leaves and young branches at night.
Control spraying the canopy using 90% dimethoate crystal 600x solution, or 20% chlorphenoxyfenad emulsion emulsion 5000x solution.
The red-banded thrips are pests of the Thripsidae of the order Taemonidae.
Adults and nymphs puncture and suck juice from leaves and young branches. The damaged leaves with spawning points are elevated on the surface of the leaves, covered with dark brown colloidal modules and yellow-brown powder particles that yellow and dry, causing the leaves to fall; when the new shoots are destroyed, the new leaves curl, brown and burn. Affects the vitality of trees.
After the new shoots of summer and autumn are extracted, when the insect population density reaches a certain level, spray 2.5% Caixi suspension 1000-1500 times, spray 1.8% avermectin emulsion 3000 times, or 25% Aitai water dispersible granules 1500 times. Liquid, 20% of the recovery can be a liquid 2000 times the solvent. Emphasis is placed on spraying young shoots, young leaves and young fruits, as well as other young tissues.
Spirulina is a pest of the genus Homoptera.
Injury state adults and nymphs damage young buds and fruits, and young fruits develop slowly after damage, even withering and losing fruit. If the fruit is in the late stages of development infringement will seriously affect the appearance and quality of the fruit.
In spring and autumn, in the new shoot and young fruit stages of spring and autumn, use 40% rapid extinguishing of 600 to 800 times liquid, 40% paracetamin emulsion 1500 to 2000 times liquid or 40% water amine thiophos emulsion 1000 liquid.
Red spider citrus is a pest of the leaf mite family Of the order Tick mites.
Harmful adult and nymphs puncture and suck sap from leaves, shoots and fruit surfaces, turning leaves yellow and causing leaves and fruits to fall.
When eggs of adult mites, nymphs, larvae and citrus red spiders coexist, use acaricides that are effective for each insect state, such as 73% mitosin emulsion and 20% phthalyl (pyridoxine) spray control agents, such as wettable powders or 34% dehui. Dehui Fengke mite emulsion 34% mite system killing emulsion concentrate, etc., can choose one of them and rotate. Two pesticides (hydrocarbons and lime sulfur) can also be formulated into a mixture for control.
Fruit borers (needle bees, yellow flies, fruit maggots) are pests of the family Dipterae.
Harmful condition adult worms lay eggs under the peel, and the larvae gather in the fruit to eat meat, causing the fruit to rot and shrink.
Control Spray the canopy with 90% of the dimethoate, 45% malathion, or 48% of lesbene and other 800 to 1 000 times dilution, spraying once every 6 to 7 days, 2 to 3 times continuously. Spraying time should be selected before 10 o'clock, or after 16 o'clock. If each 15kg of liquid medicine is added 100g of brown sugar and then diluted 5 times, it is better to spray it when it is heated to the time of aroma overflow.
In addition, there are aphids, blowing cotton aphids, etc., which can be controlled according to the occurrence of corresponding agents.