Osmanthus Common Disease and Pest Control
Plant Knowledge Series, sharing with you the knowledge of Osmanthus Clinic, the introduction of Osmanthus common disease and pest control, the following is a detailed introduction.
Leaf Spot Disease.
1. Symptoms: Mainly harms the leaves, initially small brown spots, the lesions are round or irregular in shape, later the center becomes gray to gray-white, the edges are reddish-brown, and black-gray moldy matter grows on the lesions.
2. Incidence Regularity: High temperature and humidity are often triggers, transmitted by wind and rain, and infected, the disease decreases after October.
3. Control Methods: ① In winter, prune and remove diseased leaves and clear fallen leaves, incinerate them in a centralized manner; ② In early May, spray 1:2:100-200 Bordeaux mixture, and later can spray 50% benlate 1000 to 1500 times liquid or cymazole 500 times liquid or 70% thiophanate-methyl 1000 times liquid.
Leaf Blight Disease.
1. Symptoms: Lesions often start from the tip and edges of the leaves, small spots are light brown, then expand to round or irregular shapes, lesions can connect to reach 1/3 to 1/2 of the leaf, gray-brown, edges are green, and small black dots appear on the lesions in the later stage.
2. Incidence Regularity: High temperature and humidity, poor ventilation, and weak plant growth can lead to severe disease, usually occurring from July to November, transmitted by wind and rain.
3. Control Methods: ① In the early stage of the disease, spray 65% mancozeb 500 times liquid or 1:2:200 Bordeaux mixture; ② Later, spray 50% carbendazim wettable powder 800 to 1000 times liquid or 50% benlate wettable powder 1000 to 1500 times liquid.
Spiny Moth.
1. Symptoms: Green or yellow-green, white dorsal line, most likely to occur on the back of leaves, consuming leaf flesh, leaving the epidermis.
2. Control Methods: Before the larvae descend the tree to form cocoons, loosen the soil around the trunk to attract larvae to集中 form cocoons, then collect and destroy them. Or use Bt emulsion with a spore content of over 1 billion/mL, diluted 500 to 800 times for spraying. Additionally, you can use 2.5% brom** ester emulsion or 20% cypermethrin emulsion 3000 times liquid for spraying.
Scale Insect.
1. Incidence Regularity: Can occur 2 to 3 generations in the Yangtze River Valley, with severe harm in May to June and August to September, prefers to gather on the shady side of main branches and branch forks, or on branches and leaves, both adults and nymphs secrete honeydew, leading to the occurrence of sooty mold disease in flowering plants. High temperature and humidity favor the occurrence.
2. Control Methods: When occurring in small numbers, gently brush off with a soft bristle brush for good results. In summer, using 0.3 to 0.5 degrees Baumé lime sulfur mixture spray is most beneficial, or 50% monocrotophos emulsion 1500 times liquid, alone or mixed, spray every 7 to 10 days, for 2 to 3 times.
Red Spider.
1. Incidence Regularity: Often occurs under high temperature and dry conditions.
2. Control Methods: During dry weather, pay attention to irrigation and combine with fertilization to promote plant health and enhance pest resistance. When using chemical pesticides, it is important to alternate frequently because they can develop resistance after using a certain amount of highly toxic pesticides. You can use 40% pyrethroid emulsion 2000 to 3000 times liquid or 40% dimethoate emulsion 1500 times liquid for spraying, with good control effects.
The above introduces the specific methods of Osmanthus common disease and pest control, hoping to bring some floral knowledge to flower enthusiasts.
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