Nowadays, São Paulo citrus culture faces serious problems with the outbreak of new diseases that limit the production process. One of the alternatives to prevent these diseases certainly is the production of certified seedlings, with shoot meristems and seeds of guaranteed genetic and sanitary quality, produced in containers or plastic bags, under the inspection of competent bureaus, thus assuring their health. However, it has been observed that a large part of the operational process of citrus seedling production has been partially adapted from the eucalypt production system, where, the use of plastic conic 12 cm-long cells were originally used. Such practice entails a severe morphological deformation of the root system on citrus seedlings, reducing their growth potential after field transplanting. Because the major triggering cause for citrus decline is the water stress, plants originating from this production system are much more vulnerable to the stress and, consequently, to this anomaly. Since all seedlings produced in São Paulo State come from this system, certainly citrus decline tends to be, in the near future, much more frequent and severe in the cases of vulnerable combinations for its occurrence.
Citrus; blight; rootstock; nursery tree
