brief history
Plant pathology is developed in the struggle against plant diseases. The Frenchman Doutie-Eyre first noticed that wheat smut was caused by wheat seeds contaminated with some smut; At the same time, French Prevost confirmed that this black flour is a microorganism, and put forward the suggestion of disinfection and prevention of wheat seeds with copper sulfate. But it was German H.A. Debary who formally established the theory of plant pathogens. After studying the life history of smut and pathogenic Phytophthora, he found that the spores of fungi invaded plants first, and then they became ill, thus confirming the parasitism and pathogenicity of fungi, and overthrowing the fallacious concepts such as "biological spontaneous occurrence theory" which was popular at that time, such as the so-called plant rot or rot caused by "stagnant juice". At that time, J. Kuhn of Germany studied fungal pathogens of many plant diseases and wrote the first book about crop diseases. Most of the early plant pathology researchers were mycologists, such as Prillo and A. Millardet, the first plant pathology laboratories in France. The latter published the first paper on plant pathology in 1865, and invented the bactericide bordeaux mixture. /kloc-at the end of 0/9 and the beginning of the 20th century, the United States, Italy and Japan also began to study plant pathology. The research work to prove that bacteria are one of plant pathogens began in 1878 when J. Burrill of the United States studied apple fire blight. Later, J. H.Wacker of the Netherlands published a research report that the pathogen of tulip yellowing disease is bacteria, which further confirmed the correctness of J. Burrill's theory of bacterial pathogen. The knowledge that viruses can make plants sick was confirmed by ivanovski, a Russian, in the19th century. But the research on viral diseases began in the early 20th century. In 1930s, W.M. Stanley of the United States discovered that virus was a nuclear protein structure, especially after the invention of electron microscope in 1940s, the progress in this field was more rapid.
Higher plant pathology education in China began in the early 20th century. At that time, there were Beijing Agricultural University, Nanjing Southeast University, Jinling University and Lingnan University. He has successively offered courses in plant pathology, and Zou Bingwen wrote the first monograph "Outline of Plant Pathology" in China. Since then, departments of plant pathology have been established in Jinling University, Central University, Zhejiang University and Lingnan University. Before 1930s, the research focus was mainly on pathogenic mycology, and then it gradually developed into other research fields. After 1950, our country established the specialty of plant protection or plant pathology in various agricultural colleges and universities, and trained professional graduate students and master's and doctoral students. At the same time, the prevention and control of plant diseases, such as wheat smut, smut and triticale disease, are emphasized. Through the comprehensive cooperative research on the epidemic law of three kinds of wheat stripe rust and disease-resistant breeding, the spread of wheat stripe rust in China and the characteristics of pathogenic bacteria of different physiological races were clarified, and a variety of disease-resistant varieties were selected. In addition, the occurrence, development and control of rice blast, bacterial leaf blight, sweet potato black spot, apple tree rot, potato virus disease, cabbage soft rot and cabbage solitary ding disease were also studied. The ongoing research on biological control of plant diseases will open up a new way for controlling plant diseases.
The earliest international organization of the Society of Plant Pathology is the American Society of Plant Pathology (ASPP), which was founded in 1909. The Journal of Plant Pathology of the Society was founded in 19 1 1. Organizations named after the Society of Plant Pathology in European countries were established late, but professional journals were published earlier than in the United States, such as the German Journal of Plant Pathology, which was founded in 1880. China Institute of Plant Pathology was founded in 1929, and the journal of plant pathology was published in 1955. The International Society of Plant Pathology (ISPP) was established in the UK on 1963, and botanical society of china is a member of this society.
research contents
Mainly includes the following aspects:
(1) Symptomatology. A discipline that studies the pathogenesis of plants and the types of abnormal states after diseases. Symptoms can be divided into macro and micro categories. Most of the former are discoloration or death of organs and tissues, deformity, proliferation or inhibition of plant growth, reduction of seed or fruit yield and deterioration of quality. The latter is mainly the change and destruction of the growth and development of infected plant tissues observed by microscopy, which belongs to the research category of histopathology or cytology.
(2) the cause. Study on the causes of plant diseases. Plant diseases can be divided into infectious diseases and non-infectious diseases according to their causes. The former is mostly caused by pathogenic parasites (also known as pathogens), including fungi, bacteria, viruses, bacteroides, bacteroides, rickettsia and nematodes, as well as parasitic protozoa and seed plants (see plant disease pathogens). The occurrence of diseases is the result of the interaction between pathogenic bacteria and parasitic plants under certain environmental conditions (see plant diseases). The latter is caused by abiotic factors, such as high and low temperature injury, air and water pollution, toxic substances or pesticide poisoning, excessive or insufficient nutrients in the soil, etc.
(3) Pathophysiology. The combination of plant pathology and plant physiology is a science, which mainly studies the physiological changes of infected plants from the individual level and micro level by using the principles and methods of plant physiology.
(4) Pathogenic ecology. Study on plant ecosystem. It studies the complex relationship between pathogens and host plants, as well as other biological, physical, chemical and geographical environmental conditions, and discusses the relationship between ecological balance and the occurrence and spread of diseases (see plant disease epidemiology).
(5) epidemiology. The study of the relationship between hosts, pathogens and environmental conditions at the population level. Based on pathogen ecology, the factors closely related to the occurrence, development and spread of plant diseases were quantitatively studied. Based on some key factor data, a mathematical model for predicting the epidemic of diseases was established by using mathematical analysis methods, and the actual prediction was made.
(6) disease resistance.
research contents
Including the variation mechanism and genetic law of plant disease resistance and pathogenicity of pathogenic bacteria, artificially inducing plants to enhance disease resistance, or combining disease resistance genes into a certain crop variety through hybridization. Since 1980s, the application of genetic engineering to solve plant disease resistance has developed rapidly (see Plant Disease Resistance).
(7) Comprehensive disease management. In view of the fact that single measures to prevent or treat diseases are often ineffective, the research on prevention and control measures is increasingly focused on comprehensive management to restore or maintain ecological balance, avoid or reduce environmental pollution, and achieve the purpose of controlling the occurrence and development of diseases economically, safely and effectively (see Plant Disease Prevention and Control).
Methods and prospects
There are various research methods of plant pathology. For example, the study of etiology is based on biological microplate technology, and Koch's law is verified through the procedures of separation, culture, inoculation and re-separation commonly used in microbiology and medicine. Cross breeding method and mathematical statistics analysis should be adopted in the research of disease resistance breeding. Since 1980s, the application of computer in plant disease epidemiology has provided an effective means for quantitative analysis of the relationship between epidemic factors of diseases, thus making the prediction of disease epidemic more rapid and accurate, making the comprehensive control measures more reasonable and deepening the study of disease ecosystem. On the other hand, with the progress of molecular biology, many plant pathological phenomena and plant disease-resistant or susceptible mechanisms can be analyzed and studied at the molecular level, and genetic engineering is used in disease-resistant breeding. At present, plant pathology is still developing in depth and breadth, forming new disciplines, such as seed pathology and postharvest disease research. Biological control will have a broad development space, while chemical control will tend to research and use non-toxic or low-toxic therapeutic agents and resistance agonists.