EFFECT OF FRUIT-SET TIME ON THE QUALITY PERFORMANCE OF ANNONACHERIMOLA MILL. FRUIT

The aim of this work was to analyze the differences betweenfruits obtained by different dates of fruit set and identify the properfruit-set time that allows to obtain the optimum fruit quality in Annonacherimola cv Fino de Jete, planted in Southern Italy. Six fruit-set dateswere selected from the first week of June to the second week of July.Fruits were sampled from October to November, when 1500 Growing DegreeDays (DD) were accumulated; The DD were calculated using a basetemperature of 12 °C. Fruit fresh weight (FW) and skin colour weremeasured. These parameters were measured also after storage, and inaddition, the following parameters were measured: fruit shape (FS), pulpcolour, pulp firmness, number of seeds, total soluble solids content(TSSC), titratable acidity (TA), ascorbic acid (AA), total polyphenolcontent (TPC), total antioxidant capacity (TAC) and fruit dry weight(DW). Moreover, fruit dry weight percentage, fruit fresh weight loss(FWL), and the seed index were calculated after storage.The fruit development period changed from 120 to 146 days with the fruitsetdate. The average seed number decreased with fruit set date. A strongcorrelation between fruit size and seed number occurred and also betweenthe H/D ratio and number seed. FW decreased significantly from the thirdweek of October to the first week of December and FS became progressivelyless regular in fruit coming from the 4th week of November to the 2ndweek of December. From second to five sampling the AA was highest andsimilar. The lowest values of TAC were measured in the November and earlyDecember. The correlation between TAC and AA was stronger compared to TACand TPC. All quality parameters of Annona cherimola fruit have reachedthe standards required by the market when 1500 DD have been accumulatedfrom fruit-set. Eventually, the optimal period for fruit set ranged fromend of June to the beginning of July.