How to Prevent and Control Pests and Diseases of Red Tip Photinia? Three Major Methods Explained
Red tip photinia has strong resistance, and no devastating pests or diseases have been found. Common pests and diseases of red tip photinia include damping-off, seedling blight, leaf spot, anthracnose, gray mold, leaf spot, and damage by scale insects. Below is an introduction to the three major methods for preventing and controlling red tip photinia pests and diseases.
1. Choose a Good Nursery Site
A light clay loam or sandy loam with good water sources and relatively high terrain should be chosen as the nursery site. Adhere to a crop rotation system, and do not continuously cultivate the same red tip photinia in the same nursery plot.
When raising seedlings, the nursery soil must be disinfected in advance. There are mainly the following 4 methods: ① Formalin disinfection: For each square meter of nursery, use 50 milliliters of formalin mixed with 10 kilograms of water and spray evenly over the soil surface, then cover with plastic film or straw bags, keep it sealed for about 10 days, then uncover the covering to let the gas volatilize, and sowing can be done two days later. ② Carbendazim disinfection: Use 50% wettable powder, mixing 1.5 grams per square meter. It can also be prepared into medicated soil at a ratio of 1:20 and spread on the seedbed, both of which can effectively prevent and control seedling-stage diseases. ③ Quintozene disinfection: For each square meter of nursery land, use 4 grams of 75% quintozene and 5 grams of zineb, mix them, then mix evenly with 12 kilograms of fine soil. When sowing, place it underneath and cover on top. It has a special effect on anthracnose, seedling blight, damping-off, sclerotinia rot, and other diseases. ④ Ferrous sulfate disinfection: Treat the soil with a 3% ferrous sulfate solution, using 0.5 kilograms of the solution per square meter. It can prevent and control seedling blight of coniferous ornamental plants, leaf curl disease of peach and plum, and also treat chlorosis caused by iron deficiency in flowers. The nursery land is best deep-plowed in winter, and shallow-plowed once before sowing the next year.
2. Seed Disinfection
Before sowing, the seeds should be carefully selected, and diseased and weak seeds eliminated. Before sowing, the seeds should be treated with chemicals. They can be soaked in a 0.3%-0.5% potassium permanganate solution for half an hour to 1 hour, or soaked in 50°C warm water for 24 hours. Then take out the sunken seeds and soak them in a 0.2% formalin solution for 30 minutes, then take them out and keep them sealed for 2 hours. They can also be soaked in a 0.5%-1% copper sulfate solution for 1 hour to 2 hours, then the seeds are removed, rinsed clean of the solution with clear water, dried in the shade, and sown at the proper time. Pay attention to the sowing depth, and the covering soil should not be too thick, so that the seeds can germinate and emerge.
3. Chemical Treatment
Starting from the seedling stage of red tip photinia, every 7 days to 10 days, spray 50 kilograms to 75 kilograms of 0.5%-1% Bordeaux mixture per mu of red tip photinia seedbed onto the young red tip photinia seedlings, so that a protective film forms on the outside of the young seedlings to prevent pathogen invasion. At the same time, fertilizer application must be well controlled, and manure should be piled, fermented, and thoroughly decomposed before use. After disease occurs, promptly remove diseased red tip photinia seedlings, spread lime powder around the holes of diseased seedlings to prevent spread, and apply chemicals once every 10 days to 15 days. Per mu, 100 kilograms of 500-800 times diluted dexon solution can be used, or 100 kilograms of 65% zineb 300-800 times diluted solution can be sprayed. A 1:100 methylarsenic sulfide medicated soil at 150 kilograms, or a mixed treatment of plant ash and lime powder at 8:2, can also be used. Copper-ammonia mixture can also be sprayed for treatment.
Gray mold can be prevented by spraying 50% carbendazim 1000 times diluted solution, and during the disease period, 50% zineb 800 times diluted solution can be sprayed for control. Leaf spot can be controlled with 60% carbendazim 300—400 times diluted solution or thiophanate 300—400 times diluted solution. Scale insects can be controlled by spraying dimethoate emulsion 200 times diluted solution or 800—1000 times diluted solution. Control of cutworms should be carried out before planting; the soil should be properly deep-plowed, and phosphorus-containing insecticides such as Tucong Bisha should be spread. If cutworm damage occurs after planting, remedial treatment must be carried out promptly; otherwise, once it spreads, the damage will be severe, especially to red tip photinia at the seedling stage, and may cause large-scale death.