Manganese Deficiency in Peach Trees: Prognosis and Fruit Quality

Abstract

In previous studies was pointed out that it may be possible to detect subclinical manganese deficiencies in the field before visual symptoms have developed. In this work, by in situ fluorescence measurements, we demonstrate that it is possible to predict, at the beginning of the season, which trees will develop manganese deficiency several months later. Fo/Fm ratio of young manganese deficient leaves without visible symptoms was higher than the measured in the equivalent control leaves. More than 80% of concordance, between the initial measurements and the symptoms lately developed was reached. This facts made us to believe that it could be possible to predict manganese deficiency just when the first leaves appeared and therefore apply effective correcting measures to prevent manganese deficiency in peach trees. Economical repercussion of manganese deficiency, in terms of yield and fruit characteristics, are also discussed.

Can We Approach Complete Dependence on Foliar-applied Urea Nitrogen in an Early-maturing Peach?

“…Leaf Mn concentrations correlated very well with fruit weight in each of the 5 years of both experiments (r values ranged from 0.88 to 0.99 for individual years). Since slight Mn deficiency has been shown to substantially reduce fruit weight (Val et al, 1997), future research is needed to determine the role of Mn in fruit growth or whether it is an indicator of some other physiological process affected by fertilization method. Further research is needed to test the different hypotheses.…”