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Potato Disease Prevention and Control Methods and Cultivation Techniques
I. Late Blight (1) Conditions for Onset. Potato late blight, also known as blight or potato plague, is a devastating disease of potatoes. In plots that are low-lying, poorly drained, and have high field humidity, or in plots with excessive nitrogen fertilizer application, the disease tends to be severe. When temperature and humidity are suitable, late blight spreads rapidly, and diseased plants wither and die in patches. (2) Symptoms. On affected leaves, round or irregular dark green water-soaked spots first appear at the leaf tips and margins. After expanding, they become large brown lesions. When humidity is high, a ring of
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Symptom Identification and Control Methods of Rice Dwarf Disease
The symptoms are mainly distributed in the southern rice-growing areas. Also known as rice common dwarf disease, common dwarf, green dwarf, etc. After rice is infected from the seedling stage to the tillering stage, the plant becomes dwarfed, tillering increases, leaves are dark green and stiff, and in the later growth stage the diseased rice cannot head or set grain. Diseased leaf symptoms manifest as two types. In the white-spot type, dashed-line-like yellowish-white dotted streak spots parallel to the leaf veins appear on the leaves or leaf sheaths, most obvious at the base. The new leaves above the first diseased leaf all show dotted streaks, while the older leaves below generally do not. In the twisted type, under insufficient light conditions, the heart leaf emerges twisted
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Occurrence and Control Methods of the Black Velvet Chafer in Fengxiang County, Shaanxi
The black velvet chafer (commonly known as "louhu") has a body length of 7-8 mm, a blackish-brown or purplish-brown body color, and blackish-brown fine hairs on its body surface. It has one generation per year and overwinters as an adult. In April of the following year, it emerges and becomes active, then feeds on the leaves of weeds, poplar, willow, and elm trees. After crop seedlings emerge, it migrates to sunflowers, beans, and other crops to feed and cause damage. During the day, it hides in weeds and soil cracks. It mostly flies out in groups in the evening to cause damage, biting the tender leaves of willow, elm, and fruit trees, as well as the seedlings of crops such as alfalfa, sunflower, sweet potato, potato, and kidney bean. Adults have a death-feigning habit and phototaxis. From May to
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Comprehensive Prevention and Control Methods and Technical Key Points for Porcine Respiratory Disease Syndrome
This disease is characterized by occurring throughout the year, in an endemic pattern, affecting pigs of all ages, mostly at 13-20 weeks of age, with a course of 2-8 days and a relatively high mortality rate. Symptoms: affected pigs show elevated body temperature of 40.5°C-42°C, depression, reduced or absent appetite, difficulty breathing, sometimes coughing, pale visible mucous membranes, pale or purplish skin, constipation or diarrhea, abortion and stillbirth in pregnant sows, and neurological symptoms in suckling piglets with high mortality. Pathological necropsy: necropsy of 6 dead pigs and 2 severely ill
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How to prevent and control soybean root rot? These methods you need to master
1. Choose disease-resistant varieties. 2. Rotate with non-host crops such as corn, foxtail millet, and sweet potato. 3. Apply farmyard manure, potassium fertilizer, phosphate fertilizer, etc. when sowing. 4. Apply metalaxyl granules when sowing so that soybean roots can absorb them to prevent root infection. 5. Before sowing, dress seeds with 35% metalaxyl powder at 0.3% of seed weight. 6. Strengthen field management, carry out timely deep plowing and intertillage hilling and weeding, and drain standing water promptly after rain to prevent excessive humidity. 7. When diseased plants are found, pull them out promptly, thoroughly remove the diseased plant residues, and apply quicklime to the planting holes and
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Control Methods for Fusarium Root Rot in Soybean
Symptoms: Fusarium root rot is one of the common root rots in soybean. It mainly occurs at the seedling stage. The roots and stem base of diseased plants develop elliptical brown, elongated to irregular sunken spots, which later expand into large patches encircling the main root, and some damage the lateral roots. The fungus mainly damages the cortex, causing diseased seedlings to emerge very slowly, cotyledons to lose green color, and lateral roots and fibrous roots to be few; in the later stage the roots turn black and the epidermis rots, the diseased plants turn yellow and become stunted, and the lower leaves drop early. The diseased plants generally do not die, but they set fewer pods and the seeds are small. Control methods should adopt comprehensive measures with prevention as the priority. (1) Select resistant
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Control Methods and Technical Key Points for Pests and Diseases of Asarum (Wild Ginger)
The main disease is sclerotinia rot, which mainly damages the roots. In the early stage, the base of the root becomes soft and rotting, with white filamentous substances visible, and gradually the aboveground leaves turn yellow, then lodge and die. Spray the leaves or drench the roots with a 500 to 1000 times dilution of 50% carbendazim. The main pest is the black hairy caterpillar, which generally appears in mid to late June. It damages the leaves, and in severe cases the leaves are completely eaten bare. Spray with a 1000 times dilution of dichlorvos or trichlorfon to kill them.
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What to Do About Excessive Vegetative Growth of Straw Mushroom Mycelium? Detailed Control Methods
During the mycelial growth stage of straw mushroom, a large amount of white fluffy aerial mycelium forms on the surface of the substrate, sometimes even growing into a white layer of mycelial mat, which delays fruiting and leads to low yields; the cause is excessively high temperature inside the compost heap. Control methods: after inoculating straw mushroom, regularly uncover the plastic film to ventilate and lower both temperature and humidity, and do not cover with too thick a layer of straw, so as to encourage the mycelium to grow into the substrate.
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What to Do When Straw Mushroom Mycelium Shrinks? Causes and Control Methods
1. Using inferior spawn: Spawn that is too old or too young, degenerated spawn, weak mycelial vitality, poor stress resistance, or spawn stored for a long time in environments with temperatures that are too low or too high can all lead to failure to germinate after spawning and shrinkage of mycelium in the spawn blocks. Control: Select spawn of the appropriate age and high quality, and ensure the temperature during the cultivation process does not get too low. 2. Improper control of compost temperature: When the air temperature is high, the compost is too thick, and the mushroom house has good insulation, the temperature inside the compost after spawning exceeds 42°C for an extended period, which causes mycelium to shrink and die, resulting in burning of the mycelium.
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Symptoms and Control Methods of Pythium Root Rot in Tulips
The disease can be caused by Pythium ultimum, Pythium irregulare, and Pythium intermedium, all of which are fungi belonging to the oomycetes. The pathogen overwinters in diseased bulbs, diseased roots, and soil, and often spreads with the movement of diseased soil. High soil temperature, delayed drainage after rain, and prolonged moisture retention make the disease more likely to occur. Symptoms: At the early stage of the disease, translucent water-soaked spots appear on the roots, and after expansion they cause browning of the vascular tissue, resulting in root rot. After the bulb is infected, gray spots appear around the base of the bulb with brown edges. In severe cases, the bulb becomes soft and rotted. Planting diseased bulbs
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