Ketone Test,Urine Rapid Test Strips,Animal Test Strip,Test Strips Diabetes Weight Loss Changchun Medicon Technology Development Co., Ltd , http://www.teststrip.pl
[pathogen] Huanglongbing pathogen is a kind of mycoplasma, parasitic in the phloem.
[Disease] According to the leaf performance can be divided into yellow type and mottled type, more common in the teak type mottled type. In the early stage of onset of diseased plants, there were few yellow shoots on the canopy of the shoot, followed by the main veins on the diseased shoots as the midline, and yellow and green spots were embedded, and the patch size and site were not symmetrical. The degree of yellowing of the different leaves of the same diseased plant and the different leaves of the same disease shoot was not consistent, and the new shoots removed from the diseased branches could not turn green normally, and the leaves were thick and hard and fell off early. The diseased tree has an early flowering period, a large amount of flowers, a large number of malformed flowers, and a low fruit setting rate. The fruits are smaller than normal and often appear malformed, with early ripening and low juice, thick skin, and mild taste. The diseased trees rarely make new roots, and old roots gradually rot.
[Pathogenesis] Huanglongbing mainly spreads through diseased seedlings and scions for long-distance transmission, while in orchards spreads through disease-inducing insects. It is easy to infect within 1 000 meters from the source of the disease. [Control methods] The disease is currently no feasible treatment for production applications, mainly in prevention, timely elimination of pathogens, to prevent the spread and spread.
(1) Strict implementation of the seedling quarantine system. The new district is prohibited from investigating seedlings and scion from the affected area and planting disease-free seedlings.
(2) Cultivate disease-free nursery stock: The nursery is best located in a disease-free area. Nursery establishments in wards should be selected 2 km away from citrus orchards. Scions were harvested from high-quality, disease-free trees. The conditions are best detoxified through the shoot tip grafting, identification of non-toxic and then multiply. The production of commonly used 1000ppm tetracycline hydrochloride soaked scion 2 hours, rinse with water after grafting, rootstock seeds were soaked in hot water at 55 °C for 50 minutes after sowing.
(3) Do a good job in the prevention and treatment of rafts, rafts are the vector insects transmitted by Huanglong disease, and can only damage buds and shoots. Therefore, it is necessary to do a good job of spray protection before tipping and controlling shoot tip and tender shoot stage. One of the following pesticides can be optionally used: 40% Dimethoate Emulsion 1000 to 1500 times, 40% trichlorfon 800-times 120% fast kill Ding EC 3 000 times, 2.5% Dichlor Emulsion 1 000- 1 500 times solution. Elimination of the middle host of the raft around the orchard.
(4) Timely and thorough excavation of diseased trees: Huanglong disease is most easily identified in May after the spring shoots are ripe and in the old crops after the autumn shoots are mature. In these two periods, the whole garden should be checked by the plants and the diseased plants should be found. Dig out in time. Before the excavation of the diseased tree, 300 to 500 times more Levofule should be sprayed to kill the raft so as to prevent the diseased raft from flying away and infect other trees. More than 20% of the diseased old orchards should be replanted with other crops after excavation. For the reconstruction of the ward, the diseased trees and old trees should be completely removed in a large area, and other crops should be replanted after 1 to 2 years.
Disease Prevention - Huanglongbing
Huanglongbing, also known as yellow tip disease, is a devastating disease of pomelo. The diseased plants declined in tree vigor, their yield was extremely low, and their fruit quality deteriorated until the entire tree died. The disease in southern China grapefruit production areas in Guangdong, Guangxi, Fujian and other provinces (regions) are more common.