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Exogenous Bior egulators–Fruit Composition & Storability       425

               logarithmic transformation using the analysis of variance. The differ-
               ences between means were evaluated using Duncan’s multiple range
               test at a 5 percent level of significance.
                   The result gave information on calcium uptake by fruits and short
               shoots growing in the vicinity of the fruits (i.e., organs that could com-
               pete with the fruits for calcium). In the papers of Benson and Stahly, 14
                            47
                                                      3
               Marcelle et al.,  and Banuelos and Bangerth,  only the influence of
               growth regulators on calcium uptake by fruits was investigated.
                   Their results suggest that exogenously applied growth regulators
               may change the activity of particular sinks in the plant in relation to
               calcium.
                   In both years of the 2-year experiment, daminozide had no dis-
               tinct influence on the uptake of radioactive calcium by whole plant
               segments (Tables 15.2 and 15.3). However, in 1988 this retardant
               caused a change in distribution of  Ca among particular parts of the
                                            45
               plants (Table 15.3). Thus, treatments with daminozide, regardless of
               the method of application, caused a significant drop of  Ca in long
                                                               45
               shoots while concomitantly evoking an increase of the amount of iso-
                                                       45
               tope in the fruit (Table 15.3). Some increase in  Ca content was also
               visible in short shoots; however, the differences with control were
               insignificant. In 1987, calcium distribution among analyzed plant
               parts was similar in the control and daminozide-treated branches
               (Table 15.2).
                   Differences in calcium uptake by whole analyzed segments in
               both 1987 and 1988 are not surprising in the light of the results of
                                                     26
               other authors. According to Faust and Miller  and Tromp , the influ-
                                                               72
               ence of daminozide on calcium uptake depends on numerous factors,
               for example, the relationship between shoots and fruit growth. Such
               factors change from year to year. The increased accumulation of  Ca
                                                                      45
               in fruits in 1988 probably resulted from more efficient suppression of
               the long-shoot competition by daminozide.
                   Auxin diminished radioactivity in whole-plant segments in 1988
               when it was applied 4 weeks after blooming (i.e., 3 days before the
               start of radioisotope feeding) (Table 15.3). However, there was no evi-
                                                            45
               dent influence of IAA treatment on the distribution of  Ca in particu-
               lar plant parts. Nevertheless, in 1987 the exogenous auxin applied
               2 weeks after blooming changed the distribution of calcium in inves-
               tigated plant segments (Table 15.2).
                   Translocation and uptake of calcium, and transport of IAA are
               closely independent. 2,29  Our results coincide well with those of Banu-
               elos and Bangerth.  In their experiment, treatments of fruits with auxin
                               3
               caused increased translocation of calcium to the fruits. Increased  Ca
                                                                      45
               uptake in short shoots in our experiment may also be interpreted as
               the effect of IAA transported from the fruits in a basipetal direction.
                                      45
                   A lower percentage of  Ca in the long shoots probably resulted
               from increased sink activity of the fruits due to the application of IAA.
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