-
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
-
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
-
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
-
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.
-
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
-
Methods and Technical Key Points for Controlling the White-Backed Planthopper in Rice
Damage symptoms: Adults and nymphs gather in colonies at the base of rice plants and pierce and suck the sap, causing the leaf tips of rice leaves to lose green and turn yellow, and in severe cases the whole plant withers and dies. Damage during the heading stage can also cause difficulty in heading, blighted panicles, or browning of the panicles, along with many empty grains and other damage symptoms. Morphological characteristics: Adults have two forms, the long-winged type and the short-winged type. The long-winged adult is 4-5 mm long, grayish yellow, with a rather narrow vertex projecting in front of the compound eyes; the face has 3 raised longitudinal ridges, with the ridges light in color and the grooves dark, black and white sharply distinct; in the center of the scutellum on the thoracic dorsum grows a pentagonal white or bluish-white spot; in females the
-
Identification and Control Methods for the White-backed Planthopper on Rice
Hosts include rice, wild rice, corn, barley, wheat, sugarcane, sorghum, barnyard grass, and Kentucky bluegrass. The damage characteristics are the same as those of the brown planthopper. Morphological features: The macropterous male is 3.2-3.8mm long, pale yellow, with dark brown spots. The top of the head protrudes forward; on the outer side of the lateral ridges of the pronotum and mesonotum, behind the compound eyes, there is a crescent-shaped dark brown spot; the lateral areas of the mesonotum are dark brown with a yellow longitudinal band in the middle; the forewings are semi-transparent with brownish halo spots at the tips; the wing veins, face, thorax, and ventral surface of the abdomen are dark brown. The macropterous female is 4-4
-
Management Techniques for Rice at the Jointing and Booting Stage
Management at the jointing and booting stage: When 50% of the plants in the field have the main tiller elongated by 1-2 cm and the shape of the main tiller becomes rounded, it is the jointing stage. When 50% of the flag leaves have fully emerged from the leaf sheath, it is the booting stage. This period is when rice needs the most water in its entire life cycle. If the water is drained for a long time, it will affect the formation of the panicle, resulting in small panicles and many empty grains. However, deep water flooding should also be avoided; instead, irrigate frequently with shallow water and expose the field appropriately to promote root growth, achieving deep roots and lush leaves, and striving for large panicles and more grains.
-
The correct method for broadcasting compound fertilizer during the rice stem elongation stage
During the rice stem elongation stage, topdressing is generally carried out 1 to 2 times. In previous years we used urea, but this year we switched to a high-tower granulated fertilizer. This is a compound fertilizer with high nitrogen and low phosphorus and potassium. The fertilizer granules are round and smooth on the outside, with holes inside, and have a relatively low specific gravity. Before fertilizing, we first drained the flooded water, then broadcast the compound fertilizer granules on the soil surface, and immediately let water back into the field. After the water layer was full, we found that some fertilizer granules appeared on the water surface. These floating granules were blown to one side by the wind, and some stayed in the sheltered corners.
-
Management Measures and Technical Points for Rice during the Jointing and Panicle Elongation Stage
The jointing and panicle elongation stage refers to the period from jointing and the beginning of young panicle differentiation to just before heading, generally 25-36 days for middle-season rice. 1. Growth and development characteristics and growth appearance during the jointing and panicle elongation stage (1) Growth and development characteristics During this period, on the one hand, stem elongation is the center, completing the growth of the last few leaves and root system and other vegetative organs; on the other hand, reproductive growth centered on young panicle differentiation takes place. During this period some tillers gradually die, and the total number of stems and tillers declines compared with the earlier stage, so it is an important period for preserving tillers and increasing panicles. From
条件筛选