Identification of Symptoms of Powdery Mildew on Japanese Honeysuckle and Detailed Explanation of Prevention and Control Methods
Japanese honeysuckle (Lonicera japonica) is a perennial vine-like shrub of the genus Lonicera in the Caprifoliaceae family. Its buds and nearly opened flowers are used as medicine, and the leaves and branches can also be used as medicine. It has the effects of clearing heat and detoxifying, and it is now cultivated in many cities and counties from south to north in China. Powdery mildew is a common disease on Japanese honeysuckle, occurring widely in all cultivation areas across the country, with serious damage. Now let us take a look together at what to do about powdery mildew on Japanese honeysuckle!
Symptoms of Powdery Mildew on Japanese Honeysuckle
Powdery mildew on Japanese honeysuckle mainly harms the leaves, and sometimes also harms the stems and flowers. The spots on the leaves initially appear as small white dots, then expand into white powdery patches, and in the later stage the entire leaf is covered with a white powdery layer. In severe cases, the leaves turn yellow, become deformed, and even fall off. The spots on the stems are brown, irregular in shape, and covered with white powder. The flowers become twisted and fall off in severe cases.
Patterns of Powdery Mildew on Japanese Honeysuckle
The pathogen of powdery mildew on Japanese honeysuckle is the fungus Microsphaera lonicerae of the Ascomycota. The pathogen overwinters as ascocarps on diseased plant residues. In the following year, the ascocarps release ascospores for primary infection. After the disease occurs, the diseased parts produce conidia for secondary infection. Warm and dry conditions or shaded conditions between plants make the disease likely to occur. Excessive application of nitrogen fertilizer and alternating dry and wet conditions make the disease severe.
What to Do About Powdery Mildew on Japanese Honeysuckle?
1. Disease-resistant varieties: Select disease-resistant Japanese honeysuckle varieties according to local conditions, and spray Hushu Jiangjun at appropriate times in the field for sterilization and disinfection to reduce the source of pathogens.
2. Strengthen management: Plant at a reasonable density, pay attention to ventilation and air permeability, fertilize scientifically, apply more phosphorus and potassium fertilizer, and improve the disease resistance of the plants. Before the buds of Japanese honeysuckle appear, spray Huaduo Zhuangdiling at appropriate times to promote strong buds, plump petals, bright flower color, rich fragrance, and an extended flowering period. Irrigate at appropriate times, drain promptly after rain, and prevent moisture from stagnating.
3. Chemical control: In the early stage of the disease, spray 50% colloidal sulfur 100 g mixed with 20 kg of water or 15% triadimefon wettable powder at 2000 times dilution, and at the same time spray Xingao Zhimo at 800 times dilution to improve the utilization rate of the effective ingredients of the pesticide and consolidate the control effect.
Detailed Introduction to Prevention and Control Methods for Powdery Mildew on Japanese Honeysuckle
Japanese honeysuckle is a common herbaceous ornamental flower, often used for decorating home courtyards and gardens, and it has attracted many flower lovers to grow it. The cultivation method of Japanese honeysuckle is relatively simple, so do you all know what common diseases Japanese honeysuckle has? How do you prevent and control powdery mildew on Japanese honeysuckle? Today, the editor will introduce the relevant knowledge to everyone in detail. Let us learn about it together.
Symptoms: It mainly harms the leaves, and sometimes also harms the stems and flowers. The spots on the leaves initially appear as small white dots, then expand into white powdery patches, and in the later stage the entire leaf is covered with a white powdery layer. In severe cases, the leaves turn yellow, become deformed, and even fall off; the spots on the stems are brown, irregular in shape, and covered with white powder; the flowers become twisted and fall off in severe cases.
Pathogen: Microsphaera lonicerae (Dc.) Wint. in Rabenh., called Lonicera fork-hair shell fungus, belonging to the Ascomycota fungi. Ascocarps are scattered, spherical, dark brown, 65-100 μm in size; 5-15 appendages, 55-140 μm long, 0.7-2.1 times the diameter of the ascocarp, colorless, without septa or with 1 septum, dichotomously branched 3-5 times. Asci 3-7, oval to elliptical, 34-58 × 29-49 (μm) in size. Ascospores 2-5, elliptical, 16.3-25 × 8.8-16.3 (μm) in size. The asexual stage is Oidium sp. Mycelium is superficial on both sides of the leaf, conidiophores erect, 50-94 × 7-10 (μm) in size; conidia 2-3 in chains, a few solitary, elliptical, cylindrical, produced in a basipetal manner, 28-49 × 12-20 (μm) in size.
Disease characteristics: The pathogen overwinters as ascocarps on diseased plant residues. In the following year, the ascocarps release ascospores for primary infection. After the disease occurs, the diseased parts produce conidia for secondary infection. Warm and dry conditions or shaded conditions between plants make the disease likely to occur. Excessive application of nitrogen fertilizer and alternating dry and wet conditions make the disease severe.
Prevention and Control Methods
1. Select disease-resistant varieties according to local conditions.
2. Strengthen cultivation management: Plant at a reasonable density and pay attention to ventilation and air permeability; fertilize scientifically, apply more phosphorus and potassium fertilizer, and improve the disease resistance of the plants; irrigate at appropriate times, drain promptly after rain, and prevent moisture from stagnating.
3. Chemical control: In the early stage of the disease, spray 50% colloidal sulfur 100 g mixed with 20 kg of water or 15% triadimefon wettable powder at 2000 times dilution.
Commonly used pesticides: colloidal sulfur, triadimefon
The above is all the content I have learned about Japanese honeysuckle today. I hope flower lovers will find it helpful after reading this article. If you want to learn more about Japanese honeysuckle, please continue to follow Duorou Huapu, and we will provide you with more relevant knowledge!
Prevention and Control Methods for Powdery Mildew on Japanese Honeysuckle
Damage symptoms of powdery mildew on Japanese honeysuckle:It mainly harms the leaves, and sometimes also harms the stems and flowers. The spots on the leaves initially appear as small white dots, then expand into white powdery patches, and in the later stage the entire leaf is covered with a white powdery layer. In severe cases, they turn yellow, become deformed, and even fall off; the spots on the upper part of the stems are brown, irregular in shape, and covered with white powder; the flowers become twisted and fall off in severe cases.
Disease characteristics:The pathogen overwinters as ascocarps on diseased plant residues. In the following year, the ascocarps release ascospores for primary infection. After the disease occurs, the diseased parts produce conidia for secondary infection. Warm and dry conditions or shaded conditions between plants make the disease likely to occur. Excessive application of nitrogen fertilizer and alternating dry and wet conditions make the disease severe. According to a survey by the plant protection station, it began to appear in Zhongling on April 28; on May 18, the average disease plant rate of powdery mildew was 8.9%, with a maximum of 40.0%; on May 30, the average was 17.0%, with a maximum of 20%.
Prevention and control methods:Breed disease-resistant varieties (varieties with thick branches, short and dense nodes, thick and dark green leaves, and dense hairs are mostly varieties with strong disease resistance); plant at a reasonable density, carry out shaping and pruning, and improve ventilation and light conditions, which can enhance disease resistance; apply less nitrogen fertilizer and more phosphorus and potassium fertilizer; in the early stage of the disease, use 15% fenxiuning (triadimefon) at 1500 times dilution or 50% ridomil mancozeb at 1000 times dilution or 75% chlorothalonil wettable powder at 800—1000 times dilution for spray control, once every 7 days, spraying 2-3 times continuously.