CHANGES IN SUGAR AND STARCH CONCENTRATIONS OF FORCED JUNE-BEARING STRAWBERRY PLANTS AS INFLUENCED BY FRUITING

June-bearing strawberry plants (Fragaria xananassa Duch. 'Morioka 16') were forced in a greenhouse and either allow ed to fruit or deflowere d continuously. Plants were harvested at the start of the experiment ( day 0), at full bloom (day 35), during rapid growth of green fruit (da y 53), at first fruit coloring (day 63), at full coloring of the prima ry and some secondary fruit in the primary and secondary inflorescence s (day 68), and at overripe of many primary and secondary fruit in the primary and secondary inflorescences (day 81). Dry matter accumulatio n in the vegetative organs in fruiting plants was less than that in de flowered plants as the fruit matured, but the total plant dry mass did not differ significantly between treatments throughout the forcing pe riod. Reducing sugar and sucrose concentrations in roots, crown, and o ld leaves decreased continuously until day 68, particularly in roots. The concentrations did not differ between treatments, Starch concentra tions in roots declined rapidly in both treatments between day 0 and d ay 35, and then the decline slowed. Starch level was significantly low er in the roots of fruiting plants from day 35 through fruit harvest, These results suggest that carbohydrate reserves in roots of forced Ju ne-bearing strawberry plants are used primarily to support the growth of inflorescences and developing leaves. They are less available for f ruit growth and maturation since the levels are already relatively low by this stage.