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How to control the main diseases of rice in the middle and late stages? Here are the key control points
Damage symptoms: Symptoms appear in the late seedling stage and become obvious at the peak tillering stage. Diseased plants are stunted, with light green leaves; small yellowish-white spots appear on the leaves, round or oval, often forming lines; after booting, diseased plants are significantly stunted, with plant height less than one-half that of healthy plants. Leaves are short and thick, and the central leaf is yellowish-white, sometimes curved or twisted...
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What are the symptoms of nutrient deficiency and excess nutrients in rice?
I. Overview of the occurrence In 2001, southern rice black-streaked dwarf disease was first discovered in late rice in Guangdong. In recent years, the affected area has expanded rapidly in Vietnam and the rice-growing regions of southern China. In 2009, it occurred in 9 provinces including Guangxi, Guangdong and Hunan, with an affected area of 5 million mu, and it is expected to exceed 10 million mu in 2010 (there is not yet an accurate...
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What to Do About Rice Seedling Rot? Detailed Prevention Measures
Rice seedling rot is the general term for seed rot, sprout rot and seedling death occurring at the seedling stage. Rice seedling rot can be divided into two categories: physiological and infectious. Physiological seedling rot is mainly caused by low temperatures and mistakes or poor management practices in the seedling nursery; infectious seedling rot is caused by pathogen infection, and the main diseases include rice cottony rot, rice rot disease and rice...
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Detailed Explanation of Rice Blast Resistance Breeding Techniques
The main diseases transmitted by rice seeds include bakanae disease, rice blast, rice false smut, bacterial leaf blight, and striped virus disease transmitted by the small brown planthopper at the seedling stage. Currently, it is time for soaking rice seeds in Qilin District. When soaking rice seeds, all demonstration households must insist on soaking seeds with fungicides, the main purpose of which is to kill the pathogens carried by rice seeds...
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Detailed Explanation of the Grading Standards and Control Methods for Rice Blast
Grading standards Leaf blast: Grade 1 occurs sporadically, and disease can only be seen upon careful investigation. Grade 2 has slightly more incidence, with diseased leaves concentrated in the lower part. Grade 3 has widespread incidence, with diseased leaves concentrated in the middle and lower parts. Grade 4 has relatively severe incidence, with diseased leaves concentrated in the middle and upper parts, and a small number of patches appearing. Grade 5 has severe incidence, with obvious patches...
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Occurrence of Rice Blast and Rice Planthopper and Their Control Methods
I. OccurrenceRice blast: Rice leaf blast has now appeared in Helan, Qingtongxia and other places. The first appearance date was June 13, about 10 days earlier than last year. Especially after the rainfall on July 7 and 12, the field humidity was relatively high, which was very favorable for the development of leaf blast. A recent general survey in Qingtongxia showed an average diseased field rate of 16.7%, a diseased plant rate of 2.2%, and a diseased leaf rate of 0.68%. In Helan, it occurred sporadically in some drill-seeded fields. Ear-neck blast will appear at the end of July and the beginning of August. The meteorological forecast shows that in August the temperature across the region will be relatively high and precipitation in the irrigation area will be relatively low, which is unfavorable for the occurrence and development of ear-neck blast. It is expected that ear-neck blast will generally occur at a mild-to-moderate level, with moderate to severe occurrence in fields where large areas of susceptible varieties are planted in some localities. Even so, all rice-growing counties still must not take it lightly and should strengthen monitoring. For fields with disease centers, farmers should immediately be organized to spray pesticides to block the disease centers and control the spread of fungal spores. In mid- and late July, general control should be carried out in fields where leaf blast has already occurred and in fields with high density and vigorous growth, to control the development of leaf blast and prevent the occurrence of ear blast. In early and mid-August, fields where ear-neck blast has already occurred should be sprayed promptly to control the spread of the disease. Rice planthopper: A survey in Wuzhong on July 10 found a 42% insect-hole rate; in 50 sweep-net passes, there were 32 adult brown-backed planthoppers, 10 white-backed planthoppers, 37 long-winged forms, and 5 short-winged forms. There were 60 white-backed planthopper nymphs and 151 brown-backed planthopper nymphs. A survey in Qingtongxia on July 10 found 24 insects per 100 hills.
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How to control rice false smut? Detailed explanation of its occurrence characteristics and control techniques
I. Occurrence characteristics. Rice false smut occurs only on the panicle, generally from the flowering stage to the milk-ripe stage of rice. In infected grains, the pathogen grows inside the glumes, forming false smut about 1 cm in diameter that replaces the grain. The optimum temperature for the germination and development of the rice false smut pathogen is 25-30°C; above 34°C or below 12...
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Occurrence Characteristics of Rice Planthoppers and Control Strategies
Baohe Township is located in the southwest of Jing County and belongs to a hilly area. The township has 9144 mu of cultivated land, including 7813 mu of paddy fields, and is a typical mountainous agricultural township. Rice planthoppers are a frequent pest that seriously damages rice in our township and cause losses of varying degrees every year. Especially in the past 2 years, due to the influence of a series of factors such as climate, rice production...
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What to do when rice has difficulty heading? Spraying gibberellin can alleviate it
When rice has difficulty heading, or shows the "neck-enclosed" phenomenon, the grains enclosed in the leaf sheath cannot emerge in time for pollination and fertilization, and generally become empty or blighted grains, greatly affecting yield. There are many causes of this phenomenon: in some cases the variety itself is more prone to the neck-enclosed phenomenon, and it becomes more severe under adverse environmental conditions; in others...
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Detailed Explanation of the Causes and Control Techniques of Rice Bacterial Leaf Blight
The pathogen of rice bacterial leaf blight is Xanthomonas oryzae, a bacterium belonging to the genus Xanthomonas. Bacterial leaf blight is one of the major diseases of rice. Once it occurs, it generally reduces yield by 10%, and in severe cases by 50-60%. Therefore, strengthening the control of bacterial leaf blight is very important. 1. Causes of the disease 1.1 Relationship between disease occurrence and climatic conditions...
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