Pear lice is a specialized pest on pear trees, with large incidence, hidden harm, strong resistance and other characteristics, sitting firmly on the "throne" of the first insect pest of pear trees. At present, the 1st generation of nymphs of pear lice is hatching in large quantities, which is an important node for annual control, and it is necessary to pay close attention to prevention and control, pear lice is not only an important pest on pear trees, but also the main pest of other fruit trees.
Previously, many fruit farmers and friends reported that pear lice are more difficult to fight, this time we will pick a few key parts to talk about.
The double hazard of pear lice
Direct hazards: Pear lice use adults and nymphs to suck the sap of pear leaves, fruits and young tissues, which can cause leaf curls and black spots, which have many adverse effects on tree potential and fruit quality.
Indirect harm: The honeydew secreted by pear lice will attract a large number of molds such as Streptomyces and other colonizations, and when it grows and develops, it will further produce toxins, and destroy the epidermal tissue of pear trees, forming complications.
About Honeydew
After 1 to 2 days of hatching, pear lice nymphs secrete a colorless and transparent linear wax from the tail, the main components are sugars, amino acids, waxes and so on.
The reason is that the worm only uses high-sugar and low-amino acid plant phloem sap as the only food, but when too much sugar is ingested and cannot be absorbed, the osmolality in the body will continue to rise, and the osmotic pressure can only be balanced by external excretion.
As the external discharge of honeydew increases, the mucus will wrap around the nymph, making it difficult for the agent to directly contact the insect body and affect the efficacy, so the nymph is easy to fight when it first hatches.
Three drug nodes for pear lice
(1) Stinging period: The peak period of pear lice is from the end of February to the beginning of March, the overwintering insects are usually weak and easy to fight, and have not yet spawned, timely medication is conducive to lowering the base of the insect mouth, you can choose avermectin + cypermethrin / chlorpyrifos.
(2) 1st generation nymph incubation period: generally after the flowering, at this time the nymph outer discharge of honeydew less, the insect body is exposed, convenient for the drug to contact the insect body, you can choose avermectin + imidacloprid, spiron ethyl ester, high chlorine · thiamethoxam, some people also use furazine and spirochetyl ester to increase the compound to spray, the effect is not bad, the market also has pesticide manufacturers have registered this agent.
(3) 1 generation of adult insects, 2 generations of nymphs occur: from mid-to-late May to early June, at this time the nymphs secrete a lot of mucus, and drip everywhere, if the first 2 times if the prevention is good, the pest pressure will not be too large, if there is no control in the early stage, this time can only be the scalp, so as not to affect the bagging. When the drug refers to the first generation of nymphs incubating, it can be combined with anti-penetration auxiliaries to enhance the effectiveness.
The reason why the auxiliary is to use the auxiliary is to kill the pests on the back of the leaf and in the corner of the petiole, so as to completely solve the problem.
In addition, attention should also be paid to preventing the indirect hazards caused by pear lice honeydew before the rainy season, such as spraying manganese zinc and Winji (75% Oxime and Pentazoliol dry suspension) to control mold epiphysis.
This article is written and sorted by the agricultural assistant team, please be sure to indicate the source of the agricultural assistant, and do not modify the content of the article, the modification must be investigated!