Tampilkan postingan dengan label Plant Disease. Tampilkan semua postingan
Tampilkan postingan dengan label Plant Disease. Tampilkan semua postingan

Plant Disease Forecasting

Plant disease forecasting may be a management system used to predict the incidence or modification in severity of plant diseases. At the sector scale, these systems are utilized by growers to create economic selections regarding disease treatments for management. Typically the systems raise the grower a series of questions about the susceptibility of the host crop, and incorporate current and forecast atmospheric condition to create a recommendation. Generally a recommendation is created regarding whether or not disease treatment is important or not. Sometimes treatment may be a pesticide application.

Forecasting systems are primarily based on assumptions regarding the pathogen's interactions with the host and surroundings, the disease triangle. The target is to accurately predict when the 3 factors - host, surroundings, and pathogen - all interact in such a fashion that disease will occur and cause economic losses.

In most cases the host will be suitably outlined as resistant or prone, and therefore the presence of the pathogen could typically be moderately ascertained primarily based on previous cropping history or maybe survey information. The surroundings is sometimes the issue that controls whether or not disease develops or not. Environmental conditions could confirm the presence of the pathogen in a very specific season through their effects on processes like overwintering. Environmental conditions conjointly have an effect on the power of the pathogen to cause disease, e.g. A minimum leaf wetness length is needed for gray leaf spot of corn to occur. In these cases a disease forecasting system makes an attempt to outline when the surroundings are conducive to disease development.

Good disease forecasting systems should be reliable, simple, cost-effective and applicable to several diseases. As such they're normally solely designed for diseases that are irregular enough to warrant a prediction system, instead of diseases that occur per annum that regular treatment ought to use. Forecasting systems will solely be designed if there's conjointly an understanding on the particular disease triangle parameters.

Examples of disease forecasting systems

Forecasting systems could use one in all many parameters so as to figure out disease risk, or a mixture of things. one in all the primary forecasting systems designed was for Stewart's Wilt and primarily based on winter temperature index as low temperatures would kill the vector of the disease thus there would be no outbreak.

An example of a multiple disease/pest forecasting system is that the EPIdemiology, PREdiction, and PREvention (EPIPRE) system developed within the Netherlands for winter wheat that targeted on multiple pathogens. USPEST.org graphs risks of assorted plants diseases primarily based on weather forecasts with hourly resolution of leaf wetness.

Forecasting models are typically primarily based on a relationship like easy linear regression where x is employed to predict y. Alternative relationships will be modelled using population growth curves.The growth curve that's used can rely on the character of the epidemic. Polycyclic epidemics like potato late blight are sometimes best modelled by using the logistic model, whereas monocyclic epidemics is also best modelled using the monomolecular model. Correct selection of a model is important for a disease forecasting system to be helpful.

Plant disease forecasting models should be totally tested and validated when being developed. Interest has arisen lately in model validation through the quantification of the economic prices of false positives and false negatives, where disease prevention measures is also used when unnecessary or not applied when required respectively.The costs of those sorts of errors got to be weighed fastidiously before deciding to use a disease forecasting system.
Source :
http://en.wikipedia.org/wiki/Plant_disease_forecasting

Plant Disease Diagnosis

A plant pathologist or a student taking plant pathology is commonly asked by friends or associates the following questions. What is wrong with my plant; followed by, what can i do to induce rid of the problem? It should be too late to assist the precise plant when the question is asked, however proper diagnosis may be very necessary in preventing the matter on other plants or in preventing the matter in the future.

How will a plant pathologist or a plant pathology student go regarding diagnosing plant problems? The diagnostician should have excellent observation skills, and s/he also needs to be an honest detective. It's necessary to stay an open mind till all of the facts related to the matter will be collected. the likelihood of multiple causal factors should also be thought-about.

Control measures depend on proper identification of diseases and of the causal agents. Therefore, diagnosis is one among the most necessary aspects of a plant pathologist's training. Without proper identification of the disease and also the disease-causing agent, disease control measures will be a waste of your time and cash and can result in any plant losses. proper disease diagnosis is thus vital.

Often, plant pathologists have to be compelled to believe symptoms for the identification of a disease problem. For instance, Dr. Shoe is asked by Ms. Green to examine azaleas in her nursery. When Dr. Shoe gets to the nursery, he observes that the azaleas in Greenhouse one are wilted. When he removes plants from their pots, the roots seem to be rotten. Ms. green desires to know at once what she ought to do with the azaleas in Greenhouse two where no wilting is currently being observed. Dr. Shoe is asked to form recommendations even before he has looked at plants in the second greenhouse. As a result of similar symptoms will be made in response to completely different causal agents, the utilization of symptoms alone is commonly an inadequate method for disease identification. The identification of the disease-causing agent might take every week or a lot of. What will Dr. Shoe do for Ms. Green now?

One of the most necessary things is for Dr. Shoe to use his powers of observation. He needs to ask many questions related to the azalea's care and culture in order to eliminate or determine possible causes of the matter. He also needs to take into account numerous environmental and cultural factors. As a result of his questions and observations he may:

Be able to determine a disease and disease-causing agent,

Be able to slender the matter down to many possibilities which is able to need any study in the laboratory before he can build a final diagnosis, or Be fully baffled by the matter.