BIOMETRIC PARAMETERS OF FRUITS AND STONES OF NEWLY INTRODUCED FLAT FRUIT PEACH CULTIVARS - PRUNUS PERSICA (L.) BATSCH. F. COMPRESSA

In this paper, a comparative analysis is made of the basic biometric characteristics of fruits and stones from 4 newly introduced cultivars of peaches and one nectarine belonging to Prunus persica (L.) Batsch. (f. compressa) (Flat fruit peach), selected in France (‘Platibelle’ and ‘Mesembrine’), Italy (‘UFO-4’) and Spain (‘ASF-2-80’ and ‘Flat Queen’). In Bulgaria they were imported from Spain in 2009. They are being studied in a collection plantation of the Fruit Growing Institute - Plovdiv. The highest value of fruit weight is measured for the ‘Flat Queen’ fruits – 136.01 g, and the smallest of the fruits are of the nectarine cultivar ‘Mesembrine’ - 65,24 g. It is established that in cultivars with flat-shaped fruits, the largest size is the thickness of the fruit, and the smallest is the height. The stones are small and range from 2.44 g in ‘UFO-4’ fruit to 3.35 g in ‘Flat Queen’. The relative share of the stone compared to the total fruit weight is also low and ranges from 2.26% for ‘ASF-2-80’ to 4.91% for ‘Mesembrine’. The relationship between the three fruit sizes (coefficient or index) indicates how much the shape of the fruit is closer or different than the sphere. In the sample group of cultivars close to or equal to 1 is only the width / thickness index, since the two sizes are of similar size