Continuous cropping of endangered therapeutic plants via electron beam soil treatment and neutron tomography

Various medicinal plants are threatened with extinction owing to their over exploitation and the prevalence of soil borne pathogens. In this study, soils infected with root rot pathogens, which prevent continuous cropping, were treated with an electron beam. The level of soil borne fungus was reduced to amp; 8804;0.01 by soil electron beam treatment without appreciable effects on the levels of antagonistic microorganism or on the physicochemical properties of the soil. The survival rate of 4 year old plant was higher in electron beam treated soil 81.0 than in fumigated 62.5 , virgin 78 , or untreatedreplanting soil 0 . Additionally, under various soils conditions, neutron tomography permitted the monitoring of plant health and the detection of root pathological changes over a period of 4 6 years by quantitatively measuring root water content in situ. These methods allow continual cropping on the same soil without pesticide treatment. This is a major step toward the environmentally friendly production of endangered therapeutic herb