Question: What Are The Three Factors Necessary For Disease Development?

What are the three major factors involved in the development of disease in plants?

Plant diseases– their occurrence and severity– result from the impact of three factors: the host plant, the pathogen, and the environmental conditions.

This is represented with the disease triangle.

If any one of the three factors is missing, the triangle is not complete, no disease will occur..

What are the four types of infection?

Types of infectionsViral infections. Viruses are very tiny infectious organisms. … Bacterial infections. Bacteria are single-celled microorganisms. … Fungal infections. Fungi are another diverse group of organisms that can include things like yeasts and molds. … Parasitic infections. … Prions.

How can plant diseases be prevented?

Prevent Plant Diseases With Good Gardening PracticesFollow Good Sanitation Practices.Fertilize to Keep Your Plants Healthy.Inspect Plants for Diseases Before You Bring Them Home.Allow the Soil to Warm Before Planting.Ensure a Healthy Vegetable Garden By Rotating Crops.Water in the Morning.Mulch!More items…•

What are the five signs of an infection?

Know the Signs and Symptoms of InfectionFever (this is sometimes the only sign of an infection).Chills and sweats.Change in cough or a new cough.Sore throat or new mouth sore.Shortness of breath.Nasal congestion.Stiff neck.Burning or pain with urination.More items…

What are the five environmental factors?

They include:Exposure to hazardous substances in the air, water, soil, and food.Natural and technological disasters.Climate change.Occupational hazards.The built environment.

What are the factors determining vulnerability?

Physical, economic, social and political factors determine people’s level of vulnerability and the extent of their capacity to resist, cope with and recover from hazards. Clearly, poverty is a major contributor to vulnerability.

How does plant disease occur?

The plant disease means the occurrence of physiological disorder(s) due to biotic agents such as microbial infection and/or abiotic agents such as extreme environmental factors.

What are 5 ways diseases are transmitted?

Five common ways germs are spread:Nose, mouth, or eyes to hands to others: Germs can spread to the hands by sneezing, coughing, or rubbing the eyes and then can be transferred to other family members or friends. … Hands to food: … Food to hands to food: … Infected child to hands to other children: … Animals to people:

What is an abiotic disease?

Abiotic diseases are the result of the interaction, over an extended period of time, between the plant and one or more factors such as lack of space for root growth, the presence of chronic or acute levels of air or water pollutants, or the presence of extremes of moisture, heat, light, soil pH, and nutrients.

What is the significance of the disease triangle?

The disease triangle is a conceptual model that shows the interactions between the environment, the host and an infectious (or abiotic) agent. This model can be used to predict epidemiological outcomes in plant health and public health, both in local and global communities.

What are the stages of disease development?

The five periods of disease (sometimes referred to as stages or phases) include the incubation, prodromal, illness, decline, and convalescence periods (Figure 2).

How do you tell if a plant has a disease?

A symptom of plant disease is a visible effect of disease on the plant. Symptoms may include a detectable change in color, shape or function of the plant as it responds to the pathogen. Leaf wilting is a typical symptom of verticilium wilt, caused by the fungal plant pathogens Verticillium albo-atrum and V. dahliae.

What is an abiotic disorder?

Abiotic disorders are caused by nonliving factors, such as drought stress, sunscald, freeze injury, wind injury, chemical injury, nutrient deficiency, or improper cultural practices, such as overwatering or planting conditions.

What is environmental factors in business?

Environmental factors can be both internal and external to an organization. Some internal factors of a business include its value system, mission and objectives, and internal relationships. External factors of a business include competitors, economic factors and technological factors.

What are the factors affecting disease development?

It is the interaction of crop, pathogen and environment. Epidemiology covers the effect of environmental factor prevalence, incidence and severity. A proper understanding of epidemiology is necessary for prediction of plant diseases and formulation of effective control measures.

What factors influence the occurrence of infection?

Responsible factors include ecological changes, such as those due to agricultural or economic development or to anomalies in climate; human demographic changes and behavior; travel and commerce; technology and industry; microbial adaptation and change; and breakdown of public health measures.

What is disease cycle?

Abstract. AbstractPlant disease cycles represent pathogen biology as a series of interconnected stages of development including dormancy, reproduction, dispersal, and pathogenesis. The progression through these stages is determined by a continuous sequence of interactions among host, pathogen, and environment.

Which factors are most responsible for disease in plant?

plant disease: infection from water Important environmental factors that may affect development of plant diseases and determine whether they become epiphytotic include temperature, relative humidity, soil moisture, soil pH, soil type, and soil fertility.

What are the general principles of plant disease management?

The six fundamental principles of disease management are exclusion, eradication, protection, resistance, therapy, and avoidance of insect vectors and weed hosts.

What are the 5 stages of illness?

Another sociologist, Edward A. Suchman, formulated illness behavior as con- sisting of five stages: symptom experience, assumption of the sick role, medical care contact, dependent patient, and recovery or rehabilitation (Table 1-1).

What defines a disease?

Disease, any harmful deviation from the normal structural or functional state of an organism, generally associated with certain signs and symptoms and differing in nature from physical injury. A diseased organism commonly exhibits signs or symptoms indicative of its abnormal state.