Susceptibility of New Sweet Cherry Cultivars to Rain Induced Fruit Cracking

Kod 15 novijih sorti trešnje kalemljenih na podlozi Gizela 5 proučavana je osetljivost na pucanje ploda. Ona je određivana na osnovu indeksa pucanja ploda, kao i na osnovu pucanja plodova u voćnjaku. Između ispitivanih sorti utvrđene su značajne razlike u pogledu mase ploda, sadržaja rastvorljive suve materije, indeksa pucanja ploda i broja ispucalih plodova u voćnjaku. Razlike su takođe utvrđene i između godina ispitivanja. Najveću osetljivost na pucanje ploda pokazale su sorte Samersan, Skina i Kristalina, dok su najmanje osetljive bile sorte Čelan i Regina.Susceptibility of 15 sweet cherry cultivars to rain induced fruit cracking was studied in the region of Mačva (western Serbia, along the Sava river) during a three-year period (2008-2010). Testing of fruit cracking was done using cracking index by Christensen and also by counting natural cracked fruits in orchard. In the cultivars tested significant differences in cracking index, natural cracking, fruit weight and soluble solids content were found. The three-year average fruit cracking index had the lowest value in the cultivar ‘Chelan’ (15.3) and the highest one in cultivar ‘Summer Sun’ (63.9). Natural fruit cracking varied from 9.1% (‘Chelan’) to 81.0% (‘Skeena’). Based on the cracking index, cherry cultivars were classified into three groups: moderately susceptible (4 cultivars), susceptible (8 cultivars) and highly susceptible (3 cultivars). The highest susceptibility to rain induced fruit cracking showed cultivars ‘Summersun’, ‘Skeena’, and ‘Cristalina’, while the least sensitive cultivars were ‘Chelan’ and ‘Regina’