How to control common pests and diseases of citrus?

For the citrus flower bud maggot, control can begin when the flower buds show white (about the size of a mung bean). The method is to spray the ground with 120-150 g of 90% trichlorfon crystals per mu mixed with 20 kg of water; or use 150 g of 1605 capsule formulation or 2.5-3 kg of 3% carbofuran per mu, add 25 kg of fine soil, mix well and spread on the soil surface within the drip line of the canopy. If the timing for ground application is missed, you can also, when the adults emerge, spray the canopy in the morning or evening with 80% dichlorvos emulsifiable concentrate at 1000 times dilution for control.

For citrus aphids, spray for control when 25% of the new shoots in the field are infested by aphids. The pesticides include: 20% imidacloprid wettable powder at 2000-3000 times dilution, 20% Haoniandong (Haoanwei) emulsifiable concentrate at 2000-3000 times dilution, 10% nicotine emulsifiable concentrate at 500-800 times dilution, 80% dichlorvos emulsifiable concentrate at 800 times dilution, 50% pirimicarb wettable powder at 1000-2000 times dilution, etc.

For citrus red spider mite, spray for control when there are 3-4 mites per leaf. The pesticides include: 20% pyridaben wettable powder at 4000-5000 times dilution, 50% bromopropylate emulsifiable concentrate at 1500-2500 times dilution, 5% hexythiazox emulsifiable concentrate at 2500-3000 times dilution, 50% Torque wettable powder at 3000 times dilution, 20% amitraz emulsifiable concentrate at 1500 times dilution, 10% liuyangmycin emulsifiable concentrate at 1000-1500 times dilution, 5% fenpyroximate suspension concentrate at 1000-2000 times dilution, 0.3-0.5 degrees Baume lime sulfur mixture, etc.

For citrus weevils, before the adults climb the tree, wrap the trunk with an adhesive ring (the adhesive ring formula is castor oil: rosin: yellow wax = 40:60:2), or directly apply the adhesive on the trunk to prevent the adults from climbing the tree. In addition, spray for control during the period when adults emerge from the soil. The pesticides include: 80% dichlorvos emulsifiable concentrate at 800-1000 times dilution, 50% phoxim emulsifiable concentrate at 200-300 times dilution, 50% fenitrothion emulsifiable concentrate at 800 times dilution, 25% phosmet emulsifiable concentrate at 500 times dilution or 40% dimethoate emulsifiable concentrate at 1000 times dilution, etc.

For snails, handpick and kill them when they cause damage on rainy days. Raise chickens and ducks in the citrus orchard to feed on them; during the peak egg-laying period of snails, carry out intertillage and loosen the soil to expose the eggs to the sun; use lime powder, plant ash, etc. sprinkled at night on the soil around the main trunk to repel and kill them; use 1 part calcium arsenate and 30 parts wheat bran with an appropriate amount of water to make a poisonous bait and place it in the citrus orchard for trapping and killing; use 300 g of metaldehyde, 50 g of sucrose, 300 g of 5% calcium arsenate and 400 g of rice bran (stir-fried until fragrant), mix well, add an appropriate amount of water to make soybean-sized granules for trapping and killing; use 8% miewoeling granules or 6% Mita granules, mix well with soil at a ratio of 1:10-15, and sprinkle in the evening.

For citrus psyllids, control when 20% of the leaves on spring shoots are infested by nymphs. The pesticides include: 20% imidacloprid wettable powder at 2000-3000 times dilution, 20% Haoniandong (Haoanwei) emulsifiable concentrate at 2000-3000, 3% acetamiprid emulsifiable concentrate at 1500-2000 times dilution, 40.7% chlorpyrifos emulsifiable concentrate at 1200 times dilution, 80% dichlorvos emulsifiable concentrate at 800 times dilution, pyrethroid pesticides at 1500-5000 times dilution, etc.

For citrus gummosis, treat diseased trees promptly. For young diseased trees, use disease-resistant rootstock for approach grafting to replace the rootstock, so as to restore tree vigor. For mature diseased trees, scrape off the rotten bark and the discolored xylem tissue, and apply medicine to the wounds for protection. The pesticides include 1:1:10 Bordeaux paste, 2-3% copper sulfate solution, 25% metalaxyl wettable powder at 200-300 times dilution, 70% thiophanate-methyl (or 50% carbendazim) wettable powder at 100-200 times dilution.

For seedling stem blight and anthracnose, pull out the diseased trees and spray for protection. The pesticides include 0.5% lime equivalent Bordeaux mixture, 70% thiophanate-methyl (or 50% carbendazim) wettable powder at 800-1000 times dilution, 77% Kocide wettable powder at 500-600 times dilution, etc.

For citrus resin disease, strengthen inspection and prune diseased branches.