01595naa a2200217 a 450000100080000000500110000800800410001910000190006024500540007926000090013352010480014265000120119065000120120265300130121470000180122770000180124570000150126370000190127870000160129777300640131316327771993-09-15       1992    bl uuuu     u00u1 u    #d1 aDERRICK, K. S.  aDetection of citrus blight by serological assays.  c1992  aThe symptoms of trees with blight are similar to those of a number of other declines of citrus. The finding of distinctive proteins in leaves and roots of infected trees has led to the development of serological tests that are useful in distinguishing trees with blight from those declining from other disorders. In several experiments, trees with symptoms of blight that were positive by water uptake tests and zinc wood analyses were also positive in the serological tests. In addition, some bearing trees ewere found to contain blight proteins up to one year before symptoms developed. The use of the serological tests for identification of young presymptomatic trees is being studied. In assays of blocks of young trees, blight protein positive trees are frequently identified with the number of positive trees ranging from none to up to 50% in some four-year-old plantings. The prosence of blight proteins in young presymptomatic trees couls could be an indication of infection, in which case the trees should eventually develop symptoms.  aFlorida  aDoença  aDeclinio1 aBARTHE, G. A.1 aHEWITT, B. G.1 aLEE, R. F.1 aALBRIGO, L. G.1 aIREY, M. S.  tFlorida State Horticultural Society.gv.105, p.26-28, 1992.