This period is the growth of citrus young fruit expansion period, the peak period of root growth, but also a variety of insect pest feathering, reproduction, for the peak of the fruit tree, the following for the fruit farmers to sort out the recent insect pest map and control methods, for the reference of orange farmers.
Aphids (meadowsweets)
Meadowsweet aphid morphology
Aphid hazards
Symptoms of harm: sucking on young shoots and young leaves, causing leaf curls, affecting leaf photosynthesis, and reducing nutrient accumulation.
Occurrence rules: Meadowsweet aphid occurs in multiple generations a year, 4-11 months can cause harm, especially when the citrus new shoots are drawn, the insect infestation is more serious, the current main pests citrus summer shoots and leaves, June to July is also a breeding peak period for meadowsweets.
Effective agents: praziflazone, imidacloprid, thiamethoxazine, etc
Fruit flies (citrus large fruit fly, citrus small fruit fly)
Citrus fruit fly laying eggs
Larvae infested citrus larvae
Hazard symptoms: mainly larvae as pests, adult flies lay eggs in citrus young fruits, eggs hatch into larvae and eat young fruits, and eventually form "maggot fruits", which seriously affects quality and efficiency.
Occurrence rules: Citrus large fruit flies, small fruit flies in April and May larvae feather into adults, June to August adults began to lay eggs, September eggs hatched into larvae began to eat young fruits.
Effective agents: dimethoprim, imidacloprid, thiamethoxam, etc
Leaf curl moths (pseudo-small yellow leaf curl moths)
Adult of the pseudo-yellow leaf curl moth
Larvae of the pseudo-small yellow leaf curl moth
Hazard symptoms: Leaf curl moth can harm a variety of crops, larvae moths eat young fruits, can cause a large number of fruit drops. The larvae can turn into pests, and each head can harm more than a dozen young fruits. The larvae prefer to eat smaller young fruits, especially when the transverse diameter is about 15 mm, and the damage is reduced when the transverse diameter is above 24 mm.
Occurrence pattern: Larvae moth in May and June eat young fruits, as the young fruits increase. From June to August, the larvae rarely borer fruit, but turn to the silk to bud the young leaves as a pest, and when the fruit is nearly ripe in September, the larvae can be damaged by the moth again, causing the second fruit fall.
Effective agents: octylthion, dimethoate, thuringiensis, etc
Leafminer moths (citrus leafminer moths)
Adult citrus leafminer moth
Citrus leafminer moth larvae and hazards
Harmful symptoms: Leafminer moth larvae are harmful to young buds and young leaves, and individual cases can harm the fruit. The larvae burrow under the leaf epidermis to feed on the mesophyll tissue, creating a meandering worm path and leaving a fecal line in the middle. Therefore, there are ghost drawers and drawing bugs.
Occurrence rules: from late April to early May every year, the larvae begin to harm, and July to September is the peak of the pest, and the damage is also serious. After October, the pest will decrease.
Effective agents: imidacloprid, cypermethrin, avermectin, etc
Crustaceans (yasukites, black-spotted bugs)
Yaggitan
Black spotworm
Hazard symptoms: the arrow-tipworm mainly harms the branches and leaves, nymphs and female adults suck the sap of the branches, leaves and fruits, and the heavy branches and leaves dry and shrink, weakening the tree or even dying; the black spotworm mainly harms the fruit, sucks the sap of the fruit, and seriously causes fruit drops.
Occurrence rules: Algebraic occurrence of yassip in different regions is different, Shaanxi and Gansu occur more heavily in May and August, Hunan, Hubei and Sichuan occur more heavily in mid-May, July and September, and Fujian in April, June, July, September and December. Black spotted bugs generally occur in 3-4 generations, and occur more severely in May, July, September, and October (4 generations).
Prevention and control methods: chlorpyrifos and other insecticides + mineral oil for control, and do a good job of clearing the garden in winter to reduce the source of overwintering insects.
Celestial Bull (Celestial Bull)
Star Cow Adult
Celestial bull larvae
Symptoms of harm: Adults nibble on the epidermis of branches and lay eggs under the epidermis; larvae nibble on the bark of trees and moth xylem, causing citrus nutrient absorption to be blocked and severely withered.
Occurrence rules: April to June is the peak period of feathering, June to August is the peak period of adult feeding and spawning, and the larvae moth and overwinter under the skin and xylem, and the damage period can reach more than 8 months.
Control methods: the use of chlorpyrifos, pyrethroid insecticides for drug control, with artificial control (killing adult insects, wire hooks to kill larvae, etc.)
Mites (rust ticks)
Rust tick morphology and citrus victimization
Hazard symptoms: mainly harmful to leaves and fruits, with fruit hazards more serious. After the leaves are damaged, they seem to be water-scarce and slightly rolled upwards, and the back of the leaves is smoky yellow or rusty brown, which is easy to fall off, affecting the tree potential and yield; after the fruit is damaged, the oil flows out, and it becomes black brown after being oxidized by the air, which is called "black peel fruit", which affects the quality and is not resistant to storage.
Occurrence law: May-June temperature rises, begins to appear, July-September is the peak period of occurrence, if the temperature is higher in that year, the occurrence will be aggravated.
Effective agents: pyridoxine, acetazole, spironate, etc
Source Plant Protection Science