01398naa a2200229 a 450000100080000000500110000800800410001910000180006024501630007826000090024152007460025065000120099665000120100865300120102065300130103265300130104565300150105865300160107370000180108970000140110777300470112116485422023-05-23       1992    bl uuuu     u00u1 u    #d1 aPOWELL, C. A.  aSuperinfection of orange trees containing mild isolates of citrus tristeza virus with severe Florida isolates of citrus tristeza virus.h[electronic resource]  c1992  aThe ability of four mild isolates of citrus tristeza virus (CTV) to suppress the spread of Florida severe isolates of CTV into Valencia sweet orange trees propagated on sour orange rooststock was assessed by symptom development over an 8-yr period. Decline symptoms occurred in some of the trees containing each of the mild isolates, as well as the unprotected (no mild isolate) control trees, within 3 yr after planting. After 5 yr, the percentage of decline in trees infected with the four mild isolates was 28, 22, 27, and 25, respectively, compared with 39% for the unprotected control trees. After 8 yr, the percentage of trees with symptoms (stunting or decline) was 75, 76, 74, and 73, respectively, compared with 86% for the control.  aDoença  aLaranja  aControl  aControle  aDiseases  aPropagacao  aPropagation1 aPELOSI, R. R.1 aCOHEN, M.  tPlant Diseasegv.76, n.2, p.141-144, 1992.