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Identification and Control Methods for the White-Winged Leafhopper in Rice
Scientific name Thaia rebiginosa Kuoh, formerly mistaken for Erythroneura subrufa (Motschulsky), belongs to the order Homoptera, family Cicadellidae. It is distributed south of the Yellow River and east of Xichang, Sichuan. Damage is severe in parts of the mountainous areas of Yunnan, Guizhou and Sichuan and in Hanzhong, Shaanxi. Hosts include rice, wheat, barley, sugarcane, wild rice stem, corn, rapeseed and others. Damage characteristics: adults and nymphs pierce and suck leaf sap; damaged leaves first show scattered small white spots, which later join into dotted streak marks, or white streak marks that eventually
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Detailed Explanation of Key Techniques for High-Yield Semi-Dry Rice Cultivation
① Land preparation and ridging: For winter-flooded fields, plow promptly after rice harvest, level the field surface, build high field bunds, and store water for the winter. After spring begins, generally no further plowing or harrowing is needed, but for fields with compacted soil and abundant weeds, plow and harrow once half a month before transplanting. Ridging is done in two stages. The first stage is carried out 5-7 days before transplanting, using ropes stretched to specification to open furrows and form rough ridges (for deep-footed and muddy fields, this can be moved earlier to 7-10 days before transplanting); it should not be done too early, to avoid prolonged exposure of the ridge surface, which tends to breed weeds. The second stage is carried out 2-3 days before transplanting, further raising the ridge (bed) surface according to quality requirements, clearing the furrows, and shaping them. For winter-cropped fields, after the small spring harvest, dry-plow and sun the clods for several days, then 3-4 days before transplanting let water into the field to soak it, prepare the field surface, and after the soil has settled, ridge and form beds in one operation.
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What are the advantages of semi-dry rice cultivation?
Semi-dry cultivation refers to a new rice-growing method in paddy fields where, according to a certain specification, trenches are dug and ridges are raised to form beds, rice is transplanted on the water line on both sides of the ridge top or on the bed surface, water is irrigated in the trenches, and the water level is adjusted according to the different growth stages of rice, implementing infiltrated irrigation. It is a new rice cultivation technique developed through experimental research based on the ecological characteristics of farmland, applying the principle of natural no-tillage and the theory of soil biothermodynamics. It is suitable for winter paddy fields, especially for application in deep-footed fields, cold-waterlogged fields, muddy fields and heavily fertilized fields. Therefore, in recent years, the area has expanded rapidly. 198
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What rescue measures are there after rice is flooded
Rice fields flooded for 1-4 days below 25°C suffer little damage; flooding for 1-4 days above 30°C can cause abnormal grain filling in rice; flooding for 1-4 days above 40°C can cause rice to wither and die with total crop loss. When rice is flooded at the seedling stage, the seedlings become thin and elongated with yellowing leaves, and generally are difficult to recover; at the tillering stage, the lower leaves necrose and the heart leaves curl, and after the water recedes the leaves wither, but generally do not rot; at the jointing stage, the plants become thin and weak and are prone to lodging and breaking; at the booting stage, resistance is weakest, and rotten ears and deformities easily occur, reducing the seed-setting rate; at the grain-filling stage, the lower leaves wither and yellow, the top leaves yellow, and the ears
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Detailed Explanation of Key Technical Points for Late-Stage Management of Rice in the Main Field
I. Water-Saving Irrigation Techniques During the rice growth period, water-saving techniques should be adopted for irrigation, with irrigation and drainage carried out according to the water requirements and characteristics of rice at each growth stage. These are mainly divided into deep-water greening, shallow-water tillering, deep-water booting and heading, and shallow-water ripening. During the greening stage, because the roots of the seedlings are damaged during transplanting and absorb little water while leaf transpiration is high, deep-water greening must be applied after transplanting to prevent physiological water loss, with a water depth of about 2-3 cm being appropriate. If the irrigation water is too deep, nutrient decomposition is slow, which is unfavorable for tillering; the booting and heading stage is the period of the greatest water demand in the entire life of rice
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Detailed Explanation of Key Points of Standardized Fertilization Technology for Rice
I. Fertilization Principles 1. Implement balanced fertilization According to the nutrient requirements of each crop, the soil nutrient supply status and the fertilizer effect, determine the corresponding fertilization amount and fertilization method. Based on the principle of combining organic fertilizer with inorganic fertilizer, and combining base fertilizer with topdressing, achieve balanced fertilization. 2. Implement harmless treatment of organic fertilizer Organic fertilizer produced and used by farmers themselves must undergo decomposition and fermentation, harmless treatment, and kill pathogenic microorganisms, insect eggs and weed seeds. It is prohibited to use industrial waste, urban garbage and sludge, as well as farmyard manure that does not meet
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Key Technical Points for Integrated Control of Rice Diseases, Insect Pests, Weeds and Rodents
1. Suitable areas: all rice-growing areas in Guangdong Province. The rodent control technology is suitable for controlling house mice in agriculture, forestry, livestock and poultry farming, and urban areas of Guangdong Province. 2. Key technical points for rice disease and insect pest control: (1) Agricultural control: A. Select disease- and insect-resistant, high-yielding, high-quality varieties. B. Sow and transplant at the appropriate time. C. Rational close planting and fertilization. For seedling throwing, 40 trays per mu (560 holes) is appropriate; for transplanted fields, about 20,000 hills per mu (6X5 cun), that is, about 80,000-100,000 seedlings, is appropriate. For basal fertilizer, it is recommended to apply more organic fertilizer; according to soil fertility and yield, apply an appropriate amount of nitrogen fertilizer in the early and middle stages (about 10 kg of pure nitrogen per mu), and increase the application of phosphorus and potassium fertilizers.
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Detailed Explanation of Pollution-Free Control Techniques for Rice Pests and Diseases
I. Agricultural Control Agricultural control is the foundation for achieving pollution-free control of rice pests and diseases, and its basic principle is to create an environment that favors crop growth and development while disfavoring the breeding of pests and diseases. 1. Increase the application of organic fertilizers and gradually reduce the amount of chemical fertilizers used. In production, relying solely on chemical fertilizers (especially nitrogenous chemical fertilizers) while neglecting the cultivation, composting and use of organic fertilizers is one of the important reasons for the current severe occurrence of rice pests and diseases. Therefore, it is necessary to change concepts, attach importance to developing animal husbandry, planting green manure crops and composting various types of farmyard manure, and establish a new fertilization model based primarily on organic fertilizers and supplemented by chemical fertilizers. In order to increase the sources of organic fertilizer, it is required to plow and sow green manure or other crops in winter to prevent fields from overwintering fallow. Doing so can not only reduce the overwintering base of the striped stem borer (Chilo suppressalis) and sheath blight sclerotia, but also improve the soil. Organic fertilizer is a complete fertilizer and can comprehensively supply the various nutrient elements needed by crops, but it is also a slow-release fertilizer, and most of the nutrient elements it contains cannot be directly utilized by plants; they must first be decomposed by microorganisms into ammonium nitrogen and inorganic salts before they can be absorbed. The early stage of rice growth is precisely the key period when quick-acting fertilizers (especially nitrogen fertilizer) are needed. If the required nutrients cannot be guaranteed, it will inevitably affect normal tillering, resulting in failure to grow vigorously in the early stage and then delayed maturity with excessive vegetative growth in the later stage. Therefore, when increasing the application of organic fertilizer, attention must be paid to resolving the above contradiction between supply and demand in order to achieve safe nitrogen uptake by rice (that is, continuously and evenly supplying nitrogen fertilizer according to the needs of each growth stage, neither too much nor too little, so that rice grows steadily in the early and middle stages and does not senesce prematurely or grow excessively in the later stage). For example: when green manure is the main fertilizer source, first, the total application amount must be controlled, with about 1000 kg of fresh grass applied per 667 sq m, and not too much; second, when sowing green manure, green manure varieties with different degrees of decomposition difficulty must be mixed and sown; third, plowing must be carried out early at the appropriate time to promote the decomposition of green manure. When barnyard manure and cake fertilizer are the main fertilizer sources, efforts should be made to fully decompose them before application, they should be distributed evenly during application, and attention should be paid to intermittent irrigation after transplanting to promote the decomposition of organic fertilizer. Increasing the application of organic fertilizer does not exclude the use of chemical fertilizers; the two should be combined. At the beginning of tillering, apply 50 kg to 100 kg of silicon-manganese compound fertilizer per 667 sq m in a timely topdressing to promote early and rapid growth and steady development of the seedlings, laying a good foundation for pollution-free rice production.
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What are the symptoms of viral diseases in rice?
Affected plants are stunted and the leaves become discolored, growth declines, and the leaf color turns orange to yellow. When indica rice is infected, the color is mostly orange or slightly reddish, so it is also called red leaf disease. Mottling appears on young leaves, and rust-colored spots appear on old leaves. At present, 11 kinds of rice viral diseases have been found in China (including two mycoplasma-like diseases), namely common dwarf disease, yellow leaf disease, stripe leaf blight, black-streaked dwarf disease, yellow wilt disease, grassy stunt disease, bunchy dwarf disease, ragged stunt disease, orange leaf disease, tungro disease, and tumor dwarf disease. In southern China, rice common dwarf disease and yellow leaf disease cause the most severe damage.
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Identification and Control Methods of Common Rice Diseases
1. Rice blast (1) Damage characteristics: Rice blast, also known as rice fever disease, commonly called fire blast, dangling-head blast, neck-pinching blast, etc., is one of the most widespread and most damaging fungal diseases worldwide, mainly harming the aboveground parts of the host plant. Because the damage period and site differ, it can be divided into seedling blast, leaf blast, neck blast, branch blast, grain blast, etc. Its host range includes rice, wheat, crabgrass and many other grass family plants. The rice blast pathogen mainly overwinters on diseased rice straw, and in the second year spreads from the diseased straw into rice fields to infect and cause damage. Pathogen transmission mainly relies on wind
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