Rice white head disease analysis and control

1 white pest caused by pests

The white panicles caused by rice aphid and rice planthoppers all turned white and white; the stems and stems became dry and easy to pull up after the rice bran damage; the rice stalks only killed some spikelets as white panicles, and the rice was twisted after the booting stage. The short white spikes, incomplete or emergence of flower spikes.

The white spikes that rice borer damages: The rice borers mainly include pupa, pupa, pupa and so on. In the booting stage or heading and flowering stage of rice, stems or stalks are drilled or gnawed between nodes by rice stalks, causing dead-heart strains before heading and white spikes after heading.

Indications: Sprouts at the booting stage cause damage to the booting spikes, while damage at the heading stage causes white spikes, and damage from the milking stage to the ripening stage results in damage to the plant.

Sanhuayu: from the gap between the leaves or the bite hole of the flag leaves, the first to eat in the panicle, and then gradually fell to feed, while biting through the rice section and cut off the stem and stem, causing white spike. Ants that have hatched from one egg mass can cause about 30 to 50 white spikes to form white panicle clusters, and therefore often appear in clusters in the field.

Scorpion: The first cluster was damaged in the leaf sheath. Afterwards, the transgenic plants were dispersed and invaded the stems to cause white spikes.

Prevention and control measures: Scutellariae diffusa and Saponaria japonica are the main pests of rice, and the occurrence of big warts is light, and it is generally not used alone.

(1) The control period of Sable Warts: When the damage rate is more than 1% or when the dry sheath rate reaches 5%, drug control is required. From the peak of egg incubation to the first instar larvae, the larvae are hatched. There are clusters; commonly used agents: chlorantraniliprole, methyl avermectin benzoate, insecticides, etc.

(2) Sanhuayu prevention and treatment period: In the tillering period, the drug is used to prevent dry heart during the egg incubation period, and during the egg hatching period, the control is used to control white spikes at the time of 5% to 10% of the ear opening and 10% of heading. Common agents: Chlorantraniliprole, Chloranthizide, Avic chlorpyrifos, Insecticides, etc.

Rice planthoppers: The main components are brown planthoppers, white-backed planthoppers and planthoppers. In the booting and heading stages, rice is damaged and the lower part of the rice stem becomes dark and stinky, which often causes rotten stalk lodging. In the final stage of milking, the leaf color is grayish green, the plants are inclined, and the larvae are particularly concentrated in the soft base of the spike and neck. Feeding nearby, after the whole plant ash dead and often caused by dry booties, semi-dry ear and white ear. White ear no wormholes, no insect feces. In the field, there is often a clear center of damage.

Prevention:

(1) Period of prevention and treatment: The use of 50 insects per 10 nestlings (mid-middle rice growth period) to 80 headings (mid-late rice growth period) began with medication control.

(2) Control agents: Seed treatment and application of imidacloprid and thiamethoxam for transplanting; Neprodione, nitenpyram, pymetrozine and dinotefuran were used for spraying.

Liriomyza sativae: It is the main pest in rice production, and the second generation larvae infested rice ears and caused white panicles. Liriomyes sinensis larvae penetrate into the stems of rice and endanger the heart leaves, growing points and young ears. The damaged young ears become deformed or form white ears.

Control measures: The control of rice stem fly can be controlled by using a combination of insecticidal and Kang wide.

2 diseases of white spike

Panicle-necked pheasant: Occurs in the ear and neck of the branch from the main stem to the first branch. The brown dots are formed in the early stage, and then the ear and neck are browned. After the young panicle and cob are infected by the bacteria, they lose. Damage to the guide tissue, nutrients and moisture cannot be lost, resulting in some or all of the white spikes.

Prevention:

(1) Period of prevention and treatment: Emphasis is placed on protection at the heading stage, especially at the booting stage (5 to 7 days before the break) and heading stage.

(2) Chemicals: Ai Miao, Dao Ji Ling, Fuji No. 1, and Kasugamycin.

Rhizoctonia solani: After rice sheath blight occurs, the rice base develops. If it encounters rainy days, it will expand upwards, causing all the rice leaves, ears, and grains to develop, such as spreading to the panicle, and eventually causing the rice to become dull and not full. Severely triggered white spikes.

Prevention:

(1) Control period: The key period is the time when the disease contusion rate reaches 20% after the end of the rice tiller and in the panicle stage.

(2) Chemical agents: Thiofloxacin, benzopropiconazole, epoxiconazole, imazapyr epoxiconazole, ketene, jinggangmycin A, Ai Miao et al.

Bakanae disease: Due to incomplete disinfection of rice seeds, infestation of bastard disease, disease incidence of diseased strains early heading, ear short, grain is not true, easy to cause white spike.

Preventive measures: can use prochloraz and ?f moldy spirit and so on.

Note: During the process of pest control during the rice reproductive period, it is necessary to strictly comply with the regulations and to use drugs safely so as to avoid phytotoxicity.

3 White Spike Caused by Climate

Low temperature: In the jointing and booting stage, continuous occurrence of 5 to 6 days of cold weather, the minimum temperature below 15 °C, easy to form white spikes. In particular, heading and flowering stage, encountering low temperatures, causing cold damage. If the average daily minimum temperature is lower than 18°C ​​and the daily average maximum temperature is lower than 21°C, flowering will be reduced and pollination will be hindered, resulting in the formation of a large amount of white panicles.

High temperature: The optimum temperature for rice from booting to heading and flowering is 25 to 30°C, but it is particularly sensitive to temperature at 10 days before and after heading. When the average temperature exceeds 30°C on that day, it will have an adverse effect.

Sustained high temperatures above 35°C during the booting stage will cause flowering incomplete growth, poor pollen development, and reduced vigor; heading and flowering periods in case of high temperatures above 35°C will affect pollen tube elongation, resulting in failure to fertilize and form empty pods. "Flower but not real", all the rice that heading at 38 °C temperature is not strong, high temperature can also directly kill pollen; practice shows that in the flowering period of rice, high temperature above 35 °C for 1 hour, it will cause serious spikes Infertility, where flowers that are opening up suffer the most.

Drought: When the heading and anthesis are severely drought-deficient and the relative humidity is less than 50%, white spikes may also be formed.

Preventive measures: Do a good job of corresponding water management measures.

Coping with low temperatures: Before the cold dew wind comes, deep water should be poured for insulation. On the morning of the next day, the water is drained and the river with higher temperature is irrigated in the evening to achieve the effect of heat preservation.

Coping with high temperatures: Adequate moisture is required during the booting stage, and paddy fields should maintain a 2 to 3 inch water layer to ensure that the panicles are large in size and deal with high-temperature heat damage.

During the grouting period to the milk-milk period, dry and wet-wet, wet-based methods are adopted. That is, after shallow water is poured, the water is naturally drained for 1 day and then watered; during the period of yellow ripening, shallow water is poured and then dried, and after 3 days, water is again poured. At the end of the Yellow Maturation period, irrigation was mainly based on "running horse water," that is, irrigation was performed.

4 arsenic poisoning caused by white spike

The original causes of rice arsenic poisoning are generally divided into the following two kinds:

The first kind: The cultivation of dryland cash crops for many years can lead to the accumulation of arsenic, and then replanting rice can cause arsenic poisoning into white spikes.

The second type: pesticides containing ingredients containing Formamide, an organic arsenic pesticide, used during the booting stage to the flowering stage of rice, and the use of arsenic preparations that are likely to cause pollen abortion in rice and eventually lead to poor rice or reduced seed setting rate In the control of rice blast disease, symptoms of phytotoxicity appeared 3 to 5 days after earing, and empty kernels with whitish husks on the ears resulted in white spikes.

Derma Roller

beauty mouse,china derma roller,medical grade derma roller

Goochie Beauty Equipment Co., Ltd. , http://www.gztattoos.com