Citrus wood lice
Citrus lice is a pest that has a great impact on the flowering period of citrus, we must pay attention to prevention and control, because it is the vector of yellow dragon disease, citrus growers should know that yellow dragon disease can not be saved, can only be prevented, do a good job in the prevention and control of citrus wood lice is the key measures to control and alleviate citrus yellow dragon disease.
Citrus dragon disease
Citrus xanthosis, also known as xanthosis and yellow blight, is a destructive disease caused by the infection of Phloem asiatica and occurs in citrus. It seriously affects the yield and quality of citrus, and even causes the death of citrus trees.
<h1 class="pgc-h-arrow-right" data-track="11" > morphological characteristics of citrus pyllids</h1>
Egg: The egg is mango-shaped, orange-yellow, with a blunt stalk at the upper and lower points, and 0.3 mm long.
Nymphs: flattened oval, slightly raised on the back, yellow body, a total of 5 years old. From the 3rd age, the body color is yellowish-brown in the late stages, and the wing buds begin to be exposed at the 2nd age, and short wax filaments are secreted on the periphery of the abdomen
Adults: Blue-grey body with brown markings and white powder. The head is greyish brown with a pointed front end and two buccal cones protruding from the front. The compound eyes are dark red, the one-eye is orange-red, the antennae are filamentous, and there are two hard hairs of unequal length at the ends.
<h1 class="pgc-h-arrow-right" data-track="56" > second, the pathogenic characteristics of citrus lice</h1>
High pathogenicity:
Both adult psyllids and nymphs (larvae) transmit disease, with a single adult lice transmitting rate of up to 70-80%. That is to say, adult insects that eat the sap on the leaves of diseased trees and then fly to healthy trees to feed, there is a 70-80% chance that huanglong disease bacteria will be transmitted to healthy trees.
Proximity diffusion:
Adults can fly up to 7 meters tall and travel close to the wind. The distance traveled is related to the size of the wind.
Lifelong virulence and pathogenicity of psyllids:
Venomous nymphs can transmit pathogenic bacteria to adults and do not cause the pathogenicity to disappear as the nymphs peel and become worms.
Rapid toxicity transfer:
Poison can be transmitted within 5 hours of feeding.
<h1 class="pgc-h-arrow-right" data-track="57" >3</h1>
As long as there are young shoots, adult citrus psyllids can be transferred to new shoots at any time to harm spawning, resulting in nymphs (larvae) as a pest.
1. Spring shoot period: around March to April, the spring shoot period is the first peak period of citrus wood lice breeding. Due to the first germination of diseased weak trees in the spring of each year, the adult overwintering citrus psyllids are first harmed on them, intercourse and lay eggs, breeding the first generation of nymphs, and when the spring shoots germinate in large numbers, these citrus psyllids with the pathogen of yellow dragon disease fly to the healthy trees as a pest and spread yellow dragon disease.
2. Summer shoot period: around May to June, the first summer shoots began to be withdrawn, especially young citrus as the first, becoming the second peak period of citrus lice damage. Due to the successive occurrence of summer shoots, the field insect population is continuous, the insect state is different, and the generations overlap.
3. Autumn shoot period: around July to August, the autumn shoot period is the period of the year with the largest density of insect population and the most serious damage. When the adult insect rests, the tail is cocked and at a 45-degree angle to the rest surface. At below 8 °C, it is stationary and inactive, can fly and jump at 14 °C, and begins to lay eggs and reproduce at 18 °C.
<h1 class="pgc-h-arrow-right" data-track="58" >4. Control methods of citrus psyllids</h1>
1. Strengthen cultivation management, scientific and reasonable fertilization, and keep orange trees growing strongly. Adhere to the budding and release of shoots (orchards can remove all summer shoots during the fruiting period), uniformly release autumn shoots, erase late autumn shoots, promote the neat release of citrus shoots, and reduce the early feeding and spawning and breeding sites of wood lice breeding and wintering wood lice during summer and autumn.
2. Dig out the weakened trees that have lost the ability to bear fruit and reduce the source of insects. The diseased plant must be sprayed once before digging up to prevent the psyllids from migrating outward.
3. Physical prevention and control: protection and utilization of natural enemies. Citrus lice parasitic and predatory predators mainly include: small wasps, jumping wasps, June spotted ladybugs, double-banded disc ladybirds, heterochromatic ladybirds, Asian and African grasshoppers, large grasshoppers and frog mantises, etc. In orange orchards, thistles and green manure should be planted to create a habitat for natural enemies.
4. Pharmaceutical control: quinothion, thiamethiazide, bifenthrin, high efficiency cypermethrin, high chlorine chlorpyrifosterium, mecythrin + nicotin, etc.
Remember to rotate medications and continue resistance!