The biological learning and control technology of Citrus trifolii
1. Symptoms and dangers The sharp-faced pupa are adult females, nymphs are fixed on the leaves, fruits and shoots, and the sap is formed. The macules are formed in the affected area. The leaves are deformed, curled, and the branches and leaves are dried. The victim's damaged parts are yellow-green, and the appearance is poor. Pickle. Seriously affect the tree vigor, yield and fruit quality, but also induced bituminous coal disease. In the citrus production areas are distributed, the main harm citrus, figs and so on. Siruba 747 Overlock,Overlock Sewing Machine,Siruba Sewing Machine Zhongyu Mechanical Equipment Firm , http://www.ywtattoogoods.com
Second, the morphological characteristics Female adult shell yellow-brown or brown, gray edge, front end, wide at the back, the middle has a prominent longitudinal back, like an arrowhead, so the name of the sharp point, the early hatching larval flat oval, orange, Translucent, the front has a shell point, the back shell is long, composed of white cotton wool floe, with three longitudinal backs and a yellow shell at the front. The male body is long-shaped, pinkish white, cotton-wool, 1.3-1.6 mm long, with 3 longitudinal ridgelines behind it, and the dehulled shell is located at the front and is pale yellow-brown. The larvae parasitize on citrus branches, leaves, and fruits, causing the leaves to dry, curl, shed, and shoots to die. As a result, the tree vigor is weakened and the yield is greatly reduced. After the fruit is victimized, it becomes green and the quality deteriorates.
Third, the biological learning of A. axyridis occur 2 to 4 generations a year, the field generation overlaps with female adults and a small number of young nymphs through the winter, A. acuminata from April to May every year when the average temperature reached 19 °C, the winter female adults began Spawning, after October the average temperature was below 17°C and spawning was stopped. The average egg production per female was between 38 and 165 eggs, and the fecundity was highest in overwintering. In the field, 1st instar nymphs showed three peaks in early May, mid July, and late September. It was basically extinct from late December to mid-April. Due to overwintering, insects are not neat. The first generation of the field had two peaks but the most occurred with the first peak. Warm and moist is beneficial to the survival of the sharp-eared quail, and high-temperature drying can cause a large number of deaths. Closely-closed canopies of densely planted citrus orchards make it easy to produce a sharp tip, and large-scale trees appear more severe than young trees.
Fourth, prevention and control technology
(I) Strengthen management
1. The degree of harm to the planthopper is related to tree vigor. Therefore, prevention, fertilization, antifreeze and other pest prevention and control work in citrus groves should be well done. To cultivate tree vigor and improve the body's own resistance to insects.
2. In combination with winter cutting, the insect branch, shade branch and stem branch were cut off in time before April to reduce the insect source, improve the ventilation and light transmission conditions of the citrus orchard, reduce the damage of the arrowhead tip, and pruning must be focused on burning.
3. In the fruit period, often check the garden. If it is found that the fruit surface and shoots have a pointed tip, the hazards will be promptly removed and concentrated to reduce the damage to the fruit.
(II) Chemical Control
1. In view of the occurrence of irregular first generation in the first generation, the overlapping of the generations in the future, and the increase in the body surface clam shell as the age increases, the drug resistance is enhanced, so the focus of chemical control should be placed on the first generation 1 ~ 2 instar nymphs. From the beginning of May, we regularly check whether the first-generation 2nd-instar males appear on the shoots of spring or last autumn. If they are found, they should be sprayed within 5 days, or they should be adult females from the early April. And autumn shoots were cut, inserted into a glass bottle filled with water and placed in a garden, and it was observed whether or not the newly hatched cubs climbed out. It was found that spraying was performed 21 to 25 days after the newly hatched larvae were hatched. From the end of April to mid-May, the first generation of 1st to 2nd age cornutae at the peak development stage, sprayed with 40% sulphur-containing EC 600 to 800 times, and sprayed once more in 20 days; 40% water amine Sulphur-containing EC 500 to 800 times spray, 25% quizal EC and 1% sulphate mixed and sprayed 500 times to 800 times, once in 10 days, twice in succession; 40.7% LST in 1000 times Spraying, once in 14 days, twice in succession; chlorprophos, quinophos, isocarbophos, and chlorpheniramine cannot be used in combination with alkaline pesticides; quintox, isocarbophos, and chlorpheniramine are strictly prohibited during flowering. use. Both Losbene and Isocarbophos must be discontinued 30 days before fruit harvest.
2. During the dormancy period of winter fruit trees and before germination in early spring, pine oil mixture is sprayed 8 to 10 times. Pine oil mixture cannot be mixed with other organic synthetic pesticides, nor can it be mixed with Bordeaux mixture. It is not suitable for long-term use. It should not be used when it is cold in winter. High temperature cannot be used.
(C) Biological control The major natural enemies of S. axyridis are the ladybugs, the ladybugs of the red dot, the beetle beetle, the wasp beetle, and the golden bee, which can be protected and utilized.