Effects of paclobutrazol on dry weight and mineral element distribution among fruits and shoots of 'Catherine' peach trees

摘要

Fruits and shoots of "Catherine" peach trees were analyzed to study the effects of the application of increasing rates of paclobutrazol (PP333) on the distribution of carbon and mineral elements among these organs, and mineral element concentration in leaves were determined to explain the changes observed. PP333 application did not result in differences in dry matter allocation to fruits, while it dramatically decreased the allocation to shoots. PP333 did not affect mineral element concentration in the different parts of the fruits, while increased concentrations of most elements were observed in terminal shoots, although the total amount was less in treated trees due to the reduction in shoot weight. Both in fruits and in shoots, an increase in the water content was observed. In leaves, the patterns of variation of mineral element concentration changed following the application of PP333, indicating greater exports of nitrogen (N), potassium (K), copper (Cu), and zinc (Zn), and greater accumulation of phosphorus (P), calcium (Ca), magnesium (Mg), and manganese (Mn). The results are discussed in terms of fruit-shoot competition relationships among these organs in peach trees.