Overview of the occurrence of major diseases and insects in the early rice period
At present, the field management of wasage in the whole region has entered a critical period. The overall degree of occurrence of major diseases and insects in early rice was moderate to mild and locally heavy. Compared with the same period last year, the occurrence of rice pattern blight in local rice areas was heavy; rice planthopper and rice borer borer were flat; rice longitudinal leaf borer and rice leaf blast were light.
Infographic
Rice planthopper
It is mild and moderate, and the overall degree is flat compared with the previous year. Occurrence area of 1.8 million acres.
Lamp monitoring
The initial sighting period of rice planthoppers in the early rice period is close to that of the previous year, and the peak is more than that of the previous year; the total number of single lamp insects is basically the same as that of the previous year, which is less than the usual year. Statistics Nandan and other 56 counties (cities, districts) from March 5 to May 15 the total number of single lamp insects was 2609.79 heads, basically the same as the previous year, 55.71% less than the usual year; the proportion of brown planthoppers was 18.73%, 24.31% in the previous year, and 14.36% in the perennial year.
As of early May, there have been three significant peaks in the region.
The first migration peak occurred from the end of March to the beginning of April, about 5 days later than the previous year, the main descending area in most of Guixi and Guinan, Guizhong part, statistics Pubei and other 42 counties (cities, districts) from March 26 to April 5 a total of 3251 insects, 3.55 times that of the previous year; the proportion of brown planthoppers was 24.36%, compared with 39.15% in the previous year.
The second migration peak occurred at the end of April, the main descending area was in most of Guixi and parts of guinan, and the statistics of 49 counties (cities, districts) such as Pubei had a total of 6,090 insect traps from April 21 to 25, which was 2.13 times that of the previous year; the proportion of brown planthoppers was 38.21%, compared with 33.89% in the previous year.
The third migration peak appeared at the end of May, the main descending area in Guibei, Guixi, Guinan part, statistics Nandan and other 49 counties (cities, districts) from May 6 to 10 a total of 68,093 insects, an increase of 29.39% over the previous year; of which Nandan County 5 days a total of 46,702 insects, accounting for 68.59% of the total number of attractants, is 97.30 times the previous year; the proportion of brown planthoppers is 12.05 (excluding the amount of insects in Nandan County), an increase of 23.79% in the previous year.
Field dynamics
From mid-April to late April and early mid-May, the amount of field occurrence was more than that of the previous year; the amount of occurrence in other time periods was less than that of the previous year. From the end of April to the beginning of late April, it mainly occurs in the rice area of Guinan, and the number of 100 bush insects is generally 6 to 131, the height is 390 to 836, and the individual plots are as high as 1038 to 2500 heads. In mid-May, the amount of insects in the fields of most rice areas in the Youjiang River Valley, Northwest Guizhou and Southern Guizhou showed a surge, with the number of insects in the hundred bushes generally 292 to 719 heads, the high number of 1046 to 2307 heads, and the individual fields as high as 3532 to 5110 heads; the number of individual fields in the Right River Valley was as high as 9220 heads.
Rice longitudinal curl leaf borer
The degree of occurrence is light, which is significantly lighter than that of the previous year. The area of occurrence is 1.1 million mu.
Moth volume in the field
The amount of moths caught: The amount of moths in the field in the early stage was significantly reduced, and the average daily moth catching average from April 21 to May 13 in Fangcheng, Lingshan and Bobai counties was 8.62 heads/mu, compared with 1439.32 heads/mu in the previous year. Systematic moth volume: In the previous systematic observation field survey of the whole region, the average moth volume decreased significantly compared with the previous year. From April 11 to May 15, the average number of moths per hou mu was 27.73 heads, a decrease of 66.80% over the previous year.
The amount of field occurrence was significantly reduced compared with the previous year. The main occurrence areas are guinan, most of guixi and local rice areas in central Guizhou. The number of larvae in the hundred bushes is generally 5 to 46, the height is 52 to 103, and the number of individual fields in Guinan is as high as 175 to 250.
Rice borer borer plague
The degree of occurrence is mild and locally light, which is the same as that of the previous year. The area of occurrence is 250,000 mu times. The borers that harm rice in Guangxi are mainly dihua borer, sanhua borer, Taiwan rice borer and giant borer; the pest situation of Taiwan rice borer and large borer has increased significantly. Mild occurrence of trisan borers. Dihua borer occurs lightly, the main occurrence area is the northern Guizhou, Guizhong local rice area, Guibei rice area mu has 1467 to 2400 larvae, high 5200 ~ 9200 head, individual plots up to 11000 ~ 20000 head; dry heart rate is generally 2.89% ~ 5%, high 9.53% ~ 16.33%. There are generally 55 to 338 larvae in guizhong rice area, and the highest number of individual plots is 600; the dry heart rate is generally 0.1% to 1.5%, and the high rate is 2.8% to 5%. Taiwan rice borer mainly occurs in the local rice area of southeast Guizhou, with larvae generally 1800 to 3200 heads per mu, and the maximum number of individual plots is 13800 heads; the dry heart rate is generally 0.15% to 0.73%, the high is 1.33% to 11.42%, and the individual plots are up to 31.26%.
Rice leaf blast
The degree of occurrence is mild and locally mild, slightly lighter than that of the previous year. The area of occurrence is 300,000 mu. The varieties of the disease are Deep Two Excellent Series, Y Two Excellent Series, Wild Xiang You Series, Foshan Oil Zhan, Tsuen Xiang You Series, Wu You Series, Zhuang Xiang You and Conventional Rice. The first sighting period occurred at the end of early April, about 5 days later than the previous year. The main occurrence areas are the local rice areas in central Guizhou and southern Guizhou. The diseased leaf rate is generally 0.2%-4.6%, and the high rate is 11.4%-28%; the disease refers to 0.04-0.83, the highest is 1-2.73, and the highest is 5 in guizhong individual fields.
Rice blight
The degree of occurrence is moderate to light and locally heavier, and it is heavier than that of the previous year. The area of occurrence is 1.3 million mu. The main occurrence area is most of the rice area in southern Guizhou. The first phase of the disease occurred in late April, close to the previous year. The disease cluster rate is generally 0.06% to 13.5%, the high rate is 15% to 41.67%, the local high is as high as 58% to 75%, and the maximum is more than 85% for individual plots; the disease refers to generally 0.01 to 9.1, and the maximum number of individual plots is 12.7.
In addition, harmful organisms such as rice bacterial diseases, rice orange leaf disease and other viral diseases, red blight, rice leaf water fly, rice elephant beetle, rice stalk diving fly, Fushou snail, and rat infestation also occur to varying degrees in local rice areas.
Trends in the occurrence of major pests and diseases in the middle and late period
It is expected that the incidence of diseases and insects in the middle and late stages of early rice in the whole region is moderate to heavy.
1. Rice blast
It is expected that the degree of occurrence is mild and moderate, with an area of 2.2 million mu. The main areas where the occurrence occurs are mountainous areas and historical areas where there are many varieties of diseases.
2. Rice blight
It is expected that the degree of occurrence is partial and large- and large-scale occurrence occurs in an area of 7.6 million mu, which is common in the whole region. The re-occurrence area is a high-yield rice area in northeast Guizhou and southeast Guizhou.
3. Rice planthopper
It is expected that the degree of occurrence is medium to heavy local large occurrence, with an area of 8.4 million mu, which is heavier than that of the same period last year, and it is common in the whole region.
4. Rice longitudinal curl leaf borer
It is expected that the degree of occurrence is moderately local, with an area of 6.9 million mu, and it is common in the whole region.
5. Rice borer
Sanhua borer: the degree of occurrence is expected to be mild and locally light, and the occurrence area is 700,000 mu. The main occurrence areas are most of central Guizhou and part of the rice areas of the Right River Valley and southern Guizhou. Dimorphic borer: the estimated incidence is mild and moderate, with an area of 1.2 million mu. Among them, most of the northeast and northwestern Parts of Guizhou are more serious, and the occurrence in other rice areas is on the rise. Taiwan rice borer and giant borer occur moderately in the local rice area of southern Guizhou.
6. Southern rice black strip dwarf disease
It is expected that the degree of occurrence is mild and moderate, and the occurrence area is 250,000 mu.
7. Rat infestation
It is expected that the degree of occurrence is moderately localized, with an area of 9 million mu; it is common, and the occurrence in mountainous areas and drylands is heavy.
In addition, bacterial diseases of rice, rice aspergillosis, rice tarsal mite, rice leaf water fly, rice stalk diving fly, rice thrips, rice locust, Fushou snail, rat infestation and other diseases and snails also occur to varying degrees in local rice areas.
Prevention opinions
1. In-depth field investigation to grasp the dynamics of diseases and insects
Plant protection departments at all levels should conduct in-depth field investigations, especially focusing on investigating the occurrence of migratory pests, epidemic diseases and sudden major diseases and insect pests, closely monitoring the occurrence of grassland moths (in rice, corn, sugarcane and other crops), timely grasping the dynamics of diseases and insects, and providing theoretical arguments for formulating scientific prevention and control strategies.
2. Timely reporting and accurate release of intelligence
All localities should promptly and truthfully report the current occurrence of diseases and insects to the competent agricultural departments of the local governments and the operational departments at higher levels, accurately release information on diseases and insects, make full use of television, radio, propaganda columns, self-media, and other media to release information on diseases and insects, speed up the transmission of early warning information on diseases and insects, improve the transmission speed and coverage rate of disease and insect information in the vast rural areas, and effectively guide the prevention and control of diseases and insects.
3. Clarify the main target of attack and prevent and control it in a timely manner
June is the key period for the prevention and control of major diseases and pests in the middle and late stages of early rice, and as far as the whole region is concerned, the main targets are rice planthopper, rice longitudinal leaf borer, rice ear neck blast, rice blight and rice aspergillosis. The prevention and control of viral diseases such as rice black stripe dwarf disease, rice borer borer, rice leaf water fly, rice weevil, rice stalk diving fly, rice bacterial disease, and rice flax leaf spot disease in the south cannot be ignored. Local plant protection departments should put forward scientific and effective prevention and control measures according to local conditions, and assist local governments to organize farmers to do a good job in the prevention and control of diseases and insect pests in the middle and late stages of early rice.
(Source: Guangxi Department of Agriculture and Rural Affairs official website Author: Guangxi Zhuang Autonomous Region Plant Protection Station / Text, Guangxi Agricultural Information Center / Photo)