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What are the control methods for sweet potato stem nematode disease?
Sweet potato stem nematode disease, commonly known as "chaff heart disease." [Pathogen nematode scientific name] Ditylenchus destrutor Thorne. [Host crops] Sweet potato, potato, lily, ginseng, mint, Angelica sinensis, etc. [Disease diagnosis] It mainly damages the tuberous roots, followed by the stems and vines. Tuberous roots affected
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Control Methods for Stem Rot in Sweet Potato Cultivation
Sweet potato stem rot, also known as sweet potato wilt, fusarium wilt, stem blight, etc. [Pathogen scientific name] Fusarium bulbigenum Cke. et Mass. Var. botatas Wollenw. [Host crops] Sweet potato and other Convolvulaceae plants. [Disease diagnosis] Diseased seedlings show swollen, bluish roots, with the vascular bundles turning brown and the upper parts turning yellow and thin. When mature plants are affected, the diseased plants are stunted, with swelling at the stem base and a bluish halo on the surface. When the diseased part is cut open, the vascular bundles can be seen to have turned brown after infection, extending upward from the stem base for 20 to 30 cm. Apart from a few green leaves at the top, all other leaves of the diseased plant turn yellow, and the lower old leaves successively wither and drop off. In the later stage, the cortex of the diseased part cracks, appearing fibrous, and pink mold-like growth appears on the surface. When storage roots are affected, the root end becomes rotten, and a cross-section of the discolored vascular bundle area in the upper part of the diseased root shows dark brown ring-shaped spots. The pathogenic fungus is Fusarium oxysporum f. sp. batatas. Macroconidia are sickle-shaped, with slightly pointed apical cells and slightly curved tips on the end cells, having 3 to 5 septa. Microconidia are single-celled, oval to elliptical. Chlamydospores are brown and spherical.</p><p>[Disease occurrence pattern] The pathogen overwinters as mycelium and chlamydospores in diseased storage roots or attached to diseased residues in the soil. The pathogen can also survive in the soil in a saprophytic state. The pathogen mostly invades through wounds and spreads along the vascular bundles. The cut end of transplanted seedlings is the most important invasion site, and wounds on roots and leaf scars can also allow invasion. The pathogen can also invade poorly growing seedlings. The disease can spread over long distances through diseased storage roots and diseased seedlings, and over short distances mainly through soil, flowing water, and farm tools. A soil temperature of 27 to 30°C and high soil moisture favor disease development. Frequent rainfall and large amounts of rain often cause severe outbreaks of the disease.</p><p>[Control measures] (1) Select disease-resistant varieties, such as Chaoshanbai, Nanjing 92, Jinshan 247, Taichengshu, Nanruishao, Jinqing No. 9, Xuzhou 18, etc. (2) Select disease-free seed storage roots and raise seedlings in disease-free soil. (3) Before planting, soak the sweet potato seedlings in 0.2% "401" antimicrobial agent for 10 minutes for disinfection. (4) Apply fully decomposed manure. Irrigate appropriately and drain field water promptly after rain. (5) In heavily infested plots, carry out crop rotation with grain crops for more than 3 years; rotation with rice for 1 year can already be effective. (6) Remove diseased plants promptly when found and burn them in a centralized manner or bury them deeply. (7) In the early stage of disease, spray promptly with 30% Luyedan wettable powder at 800 times dilution, or 50% benomyl wettable powder at 1500 times dilution, or 40% Shuangxiaoling aqueous solution at 800 times dilution, or 50% thiophanate-methyl wettable powder at 500 times dilution. </p>
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How to Prevent and Control Sweet Potato Stem Nematode Disease? Detailed Technical Methods
Sweet potato stem nematode disease is a devastating disease in sweet potato production. It is highly destructive and spreads quickly. It can infect and cause damage during the seedbed stage, field stage, and storage stage, but it mainly infects the tubers. Affected sweet potatoes have brown, bluish skin with cracked patterns, and the tubers are light. Some tubers show no external abnormalities, but are hollow and pithy inside. This disease not only affects the quality of sweet potatoes, but also severely affects sweet potato yield.
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What are the control methods for rice stem borers?
Netizen Yeshan Judicial Office sent an email on July 4: I am a staff member of the town agricultural technology station. Right now we have too many rice stem borers here, and they are hard to control! I had farmers use Dakuangsha and dimethoate, but the feedback was that the control effect on stem borers was poor. May I ask what methods should be used to control them
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Integrated Control Methods and Techniques for Rice Stem Borer Damage
Integrated control technology for stem borer damage refers to addressing the adverse conditions of residual toxicity, resistance, and resurgence caused by long-term pesticide application against rice stem borers, minimizing harm to humans and environmental pollution while earnestly implementing the plant protection policy of "prevention first, integrated control," persisting in carrying out pest and disease forecasting
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Occurrence patterns and control methods of soybean sclerotinia stem rot
Soybean sclerotinia stem rot occurs commonly in Heilongjiang Province. In 2001, the disease was relatively severe in Raohe County. In continuous soybean cropping fields, the disease incidence rate was 3%-30%, and in individual fields following American sunflower, the incidence rate reached 50%. In severely affected fields, the crop was even completely lost. 1 Causes of the disease 1.1 Climatic conditions In mid-to-late July, continuous low temperature and scant sunshine
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Control Methods for Cotton Red Leaf and Stem Blight
Cotton red leaf and stem blight is a physiological disease and one of the main diseases of cotton in the middle and late stages. Over the years, it has occurred severely in sandy loam soil and poor cotton fields in our county. In drought years, especially after a long drought followed by rain or during continuous overcast and rainy weather, red leaf and stem blight breaks out, and cotton plants dry up and die.
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What are the key field management techniques for Eucommia ulmoides?
Planting: After Eucommia ulmoides is planted, the root system has not yet taken firm hold, so intertillage should be shallow rather than deep, and weeds must be removed thoroughly. If intercropped with crops, it can be combined with the intertillage and weeding of the crops. Before the young Eucommia ulmoides plantation closes its canopy, the forest should be cleared and intertilled once each summer to promote the growth of young trees. Mature Eucommia ulmoides
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What are the key techniques for field cultivation of Houttuynia cordata (fish mint)?
1. Selecting seed stems. Houttuynia cordata is not propagated from seed; its rhizomes are used as planting material. Choose stems from non-flowering plants that are thick and plump, have long internodes, and have few root injuries. The seed stems should be at least 5 to 6 cm long, preferably 15 to 20 cm. Generally, it can be planted in all four seasons. However, to
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What to Do When Muskmelon Gets Gummy Stem Blight? A Detailed Guide to Prevention and Control Methods
Muskmelon, the fruit of a Cucurbitaceae plant, has fleshy fruit with multiple locules and numerous seeds, much like a berry, but the receptacle and exocarp of these fruits fuse together, often forming a thick outer rind, and in classification they are specifically called pepos, of which muskmelon is a typical example. Muskmelon gets gummy stem blight
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