The Controlled Experiment in the Scientific Method with Special Emphasis on Biological Control

The experimenter questions, manipulates, alters, controls, and the raw untreated soil is an appropriate control-this is the element forces nature to reveal herself. An experiment is game in which without interference; but what is the nature of the phenomena are carefully Watched, at particular time and place, in in this case? The sterile peat-bran medium not relation to an intentional disturbance occurring in them and infested with the biological control agent is candidate. Yet, it is around them. According to Egler (6), a controlled experiment is not the same substrate as that acted upon by the agent during one where two or more situations are watched, where one is incubation. Further, the addition of previously undigested organic observed without interference, and where the others are matter to soil can induce increased disease severity and/or toxin manipulated in known ways. The changes are then related to this production resulting from the activity of soil microflora leading to known manipulation. plant damage (15) or, alternatively, can lead to biological control The control is such an integral factor in the scientific method that (2,3). Sterile peat-bran medium has its own interference and is it is taken for granted and treated only briefly, if at all, in the not an appropriate control. philosphical literature and is only rarely defined. Indeed, in most Elimination of the biocontrol agent after growth. To allay these disciplines, control is readily identifiable; for plant pathologists, difficulties, perhaps the agent could be grown in the sterilized however, establishing controls is complicated by the multitude of peat-bran medium and then autoclaved or fumigated to remove the interacting factors in the classic disease triangle. The experiments living portion of the substrate. Much of the nutrient in the peatinvolve pathogens; therefore, there can be inoculated and bran would be utilized by the microorganism prior to the second uninoculated controls. When plant pathologists study biological sterilization; however, the dead cells, stable products extracted by control, they add new set of parameters (3) involving the the fungus during growth, and any residual unutilized nutrients