The resistance of Mangifera indica to tip dieback disease caused by Bo
tryosphaeria ribis, anamorphic state Fusicoccum sp., was determined on
361 trees of 122 mango cultivars and relatives planted in the mango g
erm plasm collection at the University of Florida, Tropical Research a
nd Education Center, Homestead. Three trees from each cultivar were ev
aluated on a 1 to 5 scale ranging from those free of tip dieback to th
ose with extensive branch necrosis. Each cultivar was assigned to one
of eight major systematic groups based on race or geographic origin. R
esistance to tip dieback disease was not associated with any of the gr
oups. No significant differences in mean disease severity were found a
mong the Indian, Southeast Asian, West Indian, Haden, or Sandersha par
ts of the Haden-Sandersha Complex, Turpentine types, or a group of unc
lassified cultivars. Two Mangifera species (M. odorata and M. zeylanic
a) showed the lowest mean disease rating. Cultivars were also grouped
into monoembryonic and polyembryonic types. Although several mango cul
tivars, mainly found in the monoembryonic group, appeared to be free o
f the disease, resistance to tip dieback was not associated with embry
ony. This study provides the first indication that field resistance to
tip dieback may be present in some mango cultivars.