ASHS 2015 Annual Conference

In the late 1990s, the Prunus Breeding and Genetics Program began to develop a series of early ripening nectarine cultivars adapted to the low chill zone (200–400 chill units) of the southern United States. This work has resulted in two pairs of nectarines that ripen in early to mid May in the low to medium chill zone of Texas. The Smooth Delight nectarines (‘Smooth Delight One’ and ‘Smooth Delight Two’) have low acid flesh and bloom about five days before ‘Flordaking’ and ripen between ‘Flordaking’ and ‘TexKing’. Thus their chilling requirement is estimated to be about 350–400 chill units. The Smooth Zest nectarines (‘Smooth Zest One’ and ‘Smooth Zest Two’) have acid sweet flesh and bloom 4–5 days after the low chill peach ‘TexFirst’, about seven days before the nectarines ‘Smooth Delight One’, Smooth Delight Two’, and ‘Suncoast’, and  12–14 days before the medium chill (450 chilling hour requirement) peaches ‘Flordaking’ and ‘TexKing’. Thus, their chilling requirement is estimated to be about 200–250 chill units. ‘Smooth Delight One’ and ‘Smooth Zest One’ have white flesh whereas the ‘Smooth Delight Two’ and ‘Smooth Zest Two’ have yellow flesh. ‘Smooth Delight One’ and ‘Smooth Delight Two’ are sister seedlings from a cross between ‘Sunmist’ and ‘Arctic Star’.  ‘Smooth Zest One’ was selected from a cross between a white fleshed semi-freestone peach selection, TX3D75W, and the low chill peach, ‘TexFirst’. ‘Smooth Zest Two’ was chosen from a cross between two nectarine selections, both which were derived from the Florida nectarine germplasm. These four firm attractive nectarines are being released for home garden and commercial use in the low to medium chill adaptation zone.