Agriculture
Reference: Introduction to Plant Pathology. Richard N. Strange. 2003. John Wiley and Sons Ltd.
- Diseases And Disorders
Diseases and DisordersThe science and study of plant diseases is known as plant pathology, which can be briefly defined as the study of the nature, cause and control of plant disease. Plant disease is as old as land plants themselves, as shown by the...
- The Mechanisms By Which Pathogens Cause Disease
Plant diseases cause a huge loose of fruits, vegetables and crops since long time ago, historically diseases causes huge loose that leads to the dead of millions of peoples on earth. During early peoples, not know the causes of diseases, they were considering...
- Mollicutes (phytoplasmas)
For nearly 70 years after viruses were discovered, many plant diseases were described that showed symptoms of general yellowing or reddening of the plant or of shoots proliferating and forming structures that resembled witches? brooms. These diseases...
- Types Of Plant Diseases
Tens of thousands of diseases affect cultivated and wild plants. On average, each kind of crop plant can be affected by a hundred or more plant diseases. Some pathogens affect only one variety of a plant. Other pathogens affect several dozen or even hundreds...
- Plants And Disease
Plants make up the majority of the earth?s living environment as trees, grass, flowers, and so on. Directly or indirectly, plants also make up all the food on which humans and all animals depend. Even the meat, milk, and eggs that we and other carnivores...
Agriculture
Establishing the Cause of Disease
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The correct diagnosis of a plant disease and its cause is not always an easy task. In the first instance symptoms may be ill defined which make their association with any organism problematic (Derrick and Timmer, 2000) and, secondly, plants grow in environments which are notably non-sterile. In particular, besides supporting a microflora on their aerial parts, the phylloplane, they are rooted in soil which may contain in excess of 1 million organisms per gram. The plant pathologist is therefore faced with trying to determine which, if any, of the organisms associated with the diseased plant is responsible for the symptoms. This is normally achieved by the application of the postulates of Robert Koch, a German bacteriologist of the 19th century, which for plant pathogens may be stated as follows:
- The suspected causal organism must be constantly associated with symptoms of the disease.
- The suspected causal organism must be isolated and grown in pure culture.
- When healthy test plants are inoculated with pure cultures of the suspected causal organism they must reproduce at least some of the symptoms of the disease.
- The suspected causal organism must be re isolated from the plant and shown to be identical with the organism originally isolated.
Reference: Introduction to Plant Pathology. Richard N. Strange. 2003. John Wiley and Sons Ltd.
- Diseases And Disorders
Diseases and DisordersThe science and study of plant diseases is known as plant pathology, which can be briefly defined as the study of the nature, cause and control of plant disease. Plant disease is as old as land plants themselves, as shown by the...
- The Mechanisms By Which Pathogens Cause Disease
Plant diseases cause a huge loose of fruits, vegetables and crops since long time ago, historically diseases causes huge loose that leads to the dead of millions of peoples on earth. During early peoples, not know the causes of diseases, they were considering...
- Mollicutes (phytoplasmas)
For nearly 70 years after viruses were discovered, many plant diseases were described that showed symptoms of general yellowing or reddening of the plant or of shoots proliferating and forming structures that resembled witches? brooms. These diseases...
- Types Of Plant Diseases
Tens of thousands of diseases affect cultivated and wild plants. On average, each kind of crop plant can be affected by a hundred or more plant diseases. Some pathogens affect only one variety of a plant. Other pathogens affect several dozen or even hundreds...
- Plants And Disease
Plants make up the majority of the earth?s living environment as trees, grass, flowers, and so on. Directly or indirectly, plants also make up all the food on which humans and all animals depend. Even the meat, milk, and eggs that we and other carnivores...