What is the difference between wheat stripe rust and wheat stripe rust?

Wheat bacterial leaf streak is distributed in Beijing, Shandong, Xinjiang, Tibet and other places, which mainly harms wheat leaves, and even leaf sheaths, stems, glumes and grains in severe cases. Dark green spots with the size of a needle tip first appear in the affected area, then expand into translucent water-soaked stripes, and then turn into dark brown, and small granular bacterial pus often appears. Brown stripes appear on leaves, so it is called bacterial stripe disease. Black glume with lesion on glume shell is called black glume.

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Xanthomonas campestris undulates)

Latin scientific name

Xanthomonas campestris pigment

boundary

Bacterial community

Distribution area

Distributed in Beijing, Shandong, Xinjiang, Tibet and other places.

Harmful crops

wheat

Morphological characteristics of 1

This bacterium is short rod-shaped, with a blunt end and extremely single flagella. Most bacteria are unicellular or bicellular, and some are chain-shaped. The size is 1 ~ 2.5×0.5 ~ 0.8(μm), with capsules and no spores. Gram staining negative aerobic. ? [ 1]?

2 route of transmission

The pathogen overwinters in the soil or on the seeds with diseased residues, invades from the natural orifice or wound of the host in the next spring, becomes ill after 3-4 days incubation period, spreads through storms in the field, and reinfects many times. [ 1]?

3. Pathogenic conditions

In Xinjiang, there are many storms from May to July, resulting in a large number of wounds on leaves and various bacterial infections, which are prone to epidemic disasters. In production, winter wheat is more susceptible to diseases than spring wheat. Xindong No.2, Yinzhong No.4, 75- 149 and 74-56 are susceptible to diseases, while Xindong No.7 and 4B- 105 are less susceptible to diseases. In spring wheat, Baiou disease is the most serious, followed by Abo disease, and Vasconcelos disease is the lightest. Generally, the soil is fertile, the sowing amount is large, and the fertilization is concentrated. In particular, the application of more nitrogen fertilizer leads to dense plants, lush foliage and poor ventilation and light transmission. [ 1]?

4 Prevention and control methods

(1) Selection of disease-resistant varieties.

(2) Sow in time, winter wheat should not be too early. Spring wheat should be planted with varieties with moderate or long growth period, and formula fertilization technology should be adopted.

(3) Soak the seeds in 45℃ water for 3 hours, dry them and sow them. You can also soak the seeds with 1% quicklime water at 30℃ for 24 hours, dry them, and then dress the seeds with 40% seed dressing powder which is 0.2% of the seed weight. [ 1]?

stripe rust of wheat

Wheat stripe rust is one of wheat rust diseases. Wheat rust, commonly known as jaundice, can be divided into stripe rust, stem rust and leaf rust. It is an important disease with wide distribution, rapid spread and large damage area in wheat production in China. Among them, wheat stripe rust is the most common and serious. Mainly distributed in Hebei, Henan, Shaanxi, Shandong, Shanxi, Gansu, Sichuan, Hubei, Yunnan, Qinghai, Xinjiang and other places.

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stripe rust of wheat

Latin scientific name

Wheat stripe rust

boundary

fungus

subdivide

basidiomycotina

Distribution area

Hebei Henan Shaanxi Shandong Shanxi Gansu Sichuan Hubei Yunnan Qinghai Xinjiang

1 dangerous symptoms

Harmful website

Wheat stripe rust mainly occurs on leaves, followed by leaf sheaths and stems, and also on ears, glumes and awns. [ 1]?

Stage characteristics

When infected at seedling stage, pale yellow summer spore piles are produced on seedling leaves. In the early stage of leaf disease, the summer spore pile is small and long, bright yellow and oval, parallel to the vein, arranged in rows, like the stitch of sewing machine roll, in dotted line shape, and the epidermis breaks in the later stage, producing rusty brown powder; When the wheat is near maturity, a round to oval pile of dark brown summer spores appears on the leaf sheath, and bright yellow powder is scattered, that is, summer spores. Black winter spore piles were produced in the late ward. The winter spore pile is short-line, flat, with constant fusion number, embedded in the epidermis, and does not crack when it matures, which is different from wheat straw rust.

Disease identification

Wheat stripe rust [2]

Stripe rust and leaf rust have serious symptoms at seedling stage in the field, which are easy to be confused and difficult to distinguish. The summer spore pile of wheat leaf rust is nearly round, large and irregularly distributed, mainly on the leaf surface, and the epidermis cracks once when it matures, which is different from stripe rust. If necessary, the summer spores of stripe rust and leaf rust can be placed on two slides respectively. After dropping a drop of concentrated hydrochloric acid on the spore, the protoplasm of stripe rust shrinks into several small balls, while the protoplasm of leaf rust shrinks into a big ball at the center of the spore. [ 1]?

2 Pathogenic characteristics

Chinese name of pathogen: wheat stripe rust (wheat specialized type)

Latin name of pathogen: Puccinia striiformis.

Taxonomic status of pathogenic bacteria: Basidiomycotina fungi

Type of disease: fungi

The mycelium is filamentous and separated, and grows in the gap between host cells. Nutrients in wheat cells are absorbed by haustorium, and spore piles are produced at the diseased site. Summer spores are spherical, bright yellow, with fine spines on the surface, and the size is (32 ~ 40) × 22 ~ 29? (Hmm), there are 6 ~ 12 germination holes. Winter spores are twin, rod-shaped, with flat or oblique cutting at the top, slightly constricted meristem, with a size of 36 ~ 68× 12 ~ 20(μm) and short stalk. The pathogenicity of this fungus has physiological differentiation. Twenty-nine physiological races have been found in China, namelyNo. 1-29. The physiological race of wheat stripe rust is easy to mutate, and the dominant race has changed five times since 1950. [ 1]?

3 route of transmission

The annual infection cycle of wheat stripe rust is mainly completed by summer spores on wheat. The host of the pathogen has not been found. Its infection cycle can be divided into four links: over-summer, autumn seedling infection, wintering and spring epidemic. Wheat stripe rust is rampant in Longdong, Longnan, eastern Qinghai, northwestern Sichuan and Gansu in China, where the average temperature in the hottest month in summer is below 20℃. After the pathogen of summer in autumn spreads to the winter wheat area in China with the airflow, it can infect the autumn seedlings of winter wheat under suitable temperature and humidity conditions, and the incidence of autumn seedlings is mostly around 1 month after winter wheat sowing. The onset and quantity of autumn seedlings are related to the distance of bacterial source and sowing date. The closer to the source of summer fungus, the earlier sowing and the more serious the disease. When the average temperature dropped to 65438 0 ~ 2℃, stripe rust began to enter the wintering period.

4. Pathogenic conditions

In Dezhou, Shijiazhuang and the north of Jiexiu, the average temperature of 1 month is below -6 ~-7℃, so the pathogen can't overwinter, while in the south of this line, the lowest monthly temperature is not lower than the above temperature in Sichuan, Yunnan, Hubei, Xinyang, Shaanxi, Guanzhong, Ankang and other places, and it can overwinter in diseased leaves in the state of hypha, becoming an important source base for local and neighboring wheat areas in spring. After the wheat turned green in the second year, the hyphae in the overwintering diseased leaves recovered and expanded. When the ten-day average temperature rises to 5℃, diseases appear and spores are produced. In case of spring rain or dew condensation, the disease spreads rapidly, leading to the epidemic in spring and becoming the main harmful period of the disease. On the premise of having a large area of susceptible varieties, the amount of overwintering bacteria and spring rainfall have become two important conditions for popularity. In case of long-term drought without rain and dew, the spread of diseases is often interrupted. Therefore, the incidence of spring drought in North China is light, and there are more spring rains in East China, but the temperature rises too fast, and high temperature is not conducive to the expansion of the disease, and the incidence is also light. It's just that the low temperature lasts for a long time in early spring and the conditions of spring rain are serious. There are obvious differences in disease resistance among varieties, but large-scale planting of varieties with the same resistance source often leads to the loss of disease resistance due to the change of pathogen races. [ 1]?

5 prevention and control methods

The disease is an air-borne disease, so it is necessary to adopt a comprehensive control strategy based on planting resistant varieties, supplemented by chemical control and cultivation measures, in order to effectively control its harm. Wheat stripe rust is a serious biological disaster that has long affected the safe production of wheat in China. Wheat production will be reduced by 10%-20% in general epidemic years, and it can be reduced by more than 60% in abnormal epidemic years, and even the wheat harvest is almost zero. According to the comprehensive analysis of the number of bacterial sources, weather conditions and variety layout, it is predicted that the occurrence of wheat stripe rust in China will be about 30 million mu in 20 1 1 year. Among them, the late-maturing wheat areas in northwest Sichuan, Longnan, southwestern Shaanxi, southern Henan, most of Xinjiang and Ningxia will be moderately or severely prevalent. Recent investigations in Mianyang, Sichuan, Shiyan, Hubei, Hanzhong, Shaanxi and other places have found that a large central disease group of wheat stripe rust has appeared. Because stripe rust is very popular and contagious, the propagation and spread of the disease is very fast under suitable temperature and humidity conditions. At present, China's main wheat producing areas are in a critical period of wheat growth. With the increase of temperature, wheat stripe rust will gradually enter the peak period. Agricultural departments at all levels should attach great importance to disease prevention and control as a key measure to win a bumper harvest of summer grain, strengthen disease monitoring, adopt zoning prevention and control strategies, select efficient pesticide varieties, prevent and control disease epidemics in time, and ensure a bumper harvest of wheat.

Planting management

(1) Select resistant varieties to make the distribution of resistant sources reasonable and the varieties rotate regularly. M8003 and Changwu131can be selected for dry land in Shaanxi; Shaanxi 229 and Shaanxi 86 1 can choose dry and fertile land; Shan 927, Shan 160, Xinong 88- 1, Shuiyan 107, Zhi 8 1 168 can be selected as water areas. Gansu can choose Tianxuan 40, Tian882, Mianyang 15, Mianyang 19 and Mianyang 20; Chuanyu 9 and Chuanyu10; Hebei can choose McKee 19, McKee 26, McKee 54 18, Kang Feng 13, Jing Yao 626 and so on. Henan can choose Yumai 17, Zheng 8329, Xuzhou 2 1 and Zheng 891; Young Mai No.4 and No.5 can be selected in the lower reaches of the Yangtze River. In addition, China has also cultivated a large number of new varieties resistant to stripe rust, which can be selected according to local conditions. Such as JD.COM No.8, Jinghe No.3 (93 1), Jing 4 1, Dongmai1,Beinongbai, Bainong 64, Zhengzhou 89 15, 94 1 and Zhoumai 9. Yumai 35 and 39, Chuanmai 24 and 25; Mianyang 25, 26, Chuannongmai 1, Shuwan 41; Ji Shen Stone 4 185, McKee 38, 40, 4 1, 6021(9306); Wanmai 26, 27, 28, Zaomai 5, Dianmai 18, 19, 20, vama 8, Qinmai 12, Xinong 1376. Spring wheat includes Kenjiu No.5, Linmai No.29 and No.30, Longchun 15, Ningchun No.24, Longchun No.9, Longchun No.8139, Ding Feng No.3, Jinghong No.8, Kechun 14, Chun Qing No.26 and No.533, etc. When applying disease-resistant varieties, pay attention to the rational layout of rust-resistant varieties. Using the diversity or heterogeneity of population resistance of resistant varieties to control the change of rust population composition and the formation of dominant races. Avoid a single variety, but not too many, and pay attention to regular rotation to prevent the loss of resistance. Select effective drug varieties:

Vigorously promote the high-efficiency and low-toxicity systemic fungicides based on triazoles and diniconazole for field spray control. Spraying 80-100g triadimefon powder per mu, or spraying 30-40g diniconazole powder per mu, or spraying 40ml 12.5% suspending agent per mu, the control effect can reach over 90%.

(2) Agricultural control

① Sowing at the right time, sowing at the right time, not too early, can reduce the occurrence of stripe rust in autumn seedling stage.

② Remove autologous wheat.

(3) Advocating the application of decomposed organic fertilizer made of compost or enzyme bacteria, increasing the application of phosphorus and potassium fertilizer, and doing a good job in the reasonable collocation of nitrogen, phosphorus and potassium to enhance the disease resistance of wheat. Available nitrogen should not be too much or too late to prevent wheat from being greedy for green and late maturing, which will aggravate the damage.

(4) Reasonable irrigation, pay attention to ditching and drainage when the soil moisture is high or after rain, and properly irrigate when the disease is serious in the later period to reduce the yield loss.

The basic measure to control wheat stripe rust is to plant disease-resistant varieties according to local conditions. After wheat harvest, timely ploughing and stubble clearing, eliminating autogenous wheat seedlings and reducing overwintering bacteria sources can reduce the incidence of wheat. [3]?

Chemical control

(3) Chemical Control Chemical control is needed in wheat areas where there are no disease-resistant varieties or the rust resistance of the original disease-resistant varieties is lost, and there are no subsequent varieties. In China, the effective fungicides for rust include disodium salt, disodium salt, barium fluoride preparation, calcium sulfamate, fluorosilicone urea, weixiuling, bactericidal Dan, zineb and so on. In recent years, triadimefon and terbutazole have been mainly promoted.

① Triadimefon is 0.03% of the seed weight (active ingredient), that is, 25% triadimefon wettable powder 15g is mixed with wheat seeds 150kg, or 12.5% terbutazole wettable powder is mixed with wheat seeds 50kg.

② The incidence of diseased leaves in spring wheat is 2% ~ 4% from jointing stage to booting stage. When the severity reaches 65,438+0%, spraying 20% triadimefon EC or 65,438+02.5% terbutazole (diniconazole, quick-polymerization) wettable powder 65,438+0,000 ~ 2,000 is started. When wheat rust, leaf blight and sheath blight are mixed, at the initial stage of the disease, 20 ~ 35g of 12.5% terbutazole wettable powder is used to spray water at 667m^2, and 50 ~ 80l is very effective, which can not only control rust, but also treat leaf blight and sheath blight.

Strengthen monitoring

Strengthen disease surveillance:

Agricultural plant protection departments at all levels should closely monitor the occurrence of wheat stripe rust in accordance with the investigation norms, and conscientiously do a good job in fixed-point observation and field investigation of the disease; Accurately grasp the dynamics of stripe rust, and timely issue forecasts and prevention alarms according to the development and changes of the disease; Inform government departments and superior business departments of the occurrence of diseases in time, and provide reliable basis for disease prevention and control decisions.

Adopt zoning prevention and control strategy:

At present, we should focus on early pesticide control in winter breeding areas such as northwest Hubei, Sichuan Basin, southern Henan, southern Shaanxi, Chongqing, Guizhou and Yunnan, and take "drug reconnaissance" to control epidemic spots in time; Provide unified prevention and control of wheat fields and control the regional spread of diseases. In the spring epidemic areas such as the Yellow River, Huaihe River and Shanghai, it is necessary to strengthen the disease monitoring and spray drugs when the incidence reaches 5%. In the areas which are changeable in summer, such as southeast Gansu, northwest Sichuan, south Ningxia and Haidong (the fungus source base in autumn), we should adopt rust-resistant improved varieties and chemical seed dressing, combined with comprehensive measures such as stopping sowing and late sowing of wheat.