Growth and survival of 20 peach rootstocks and selections in South Carolina

Eighteen Prunus rootstock cultivars and selections budded with either 'Redtop' or 'Redhaven' peach and another 11 budded with 'Redhaven' were planted at 2 locations in South Carolina in 2001, 2002, and 2003. In 2001, 'Redtop' trees were planted near Clemson, South Carolina as part of a NC-140 Cooperative Regional Rootstock Project. A 'Redhaven' NC-140 planting was added in 2002 adjacent to the 'Redtop'. A 2003 'Redhaven' test was planted on a severe bacterial canker site near Columbia, South Carolina. There were 20 different rootstocks tested, which included three peach seedling rootstocks, 'Lovell', 'Bailey', and 'Guardian'(TM) BY520-9 [selection SC-17]. Clonal rootstocks included peach x almond hybrids 'BH-4', 'SLAP', and 'Monegro'; peach x plum hybrids 'K146-43' [=Controller 5], 'K146-44', and 'P30-135' [=Controller 9]; interspecific plum hybrids 'Citation', 'Hiawatha', 'Jaspi' and 'Julior'; interspecific Prunus hybrids 'Cadaman', 'VVA-1' [=Krymsk 1], 'VSV-1' [=Krymsk 2]; and Prunus L. species selections 'Adesoto 101' [=Empyrean 101], 'PumiSelect', 'Mr.S 2/5', and 'Penta' [=Empyrean 2]. At the Clemson location, 'PumiSelect' and 'SC-17' were the most vigorous rootstocks, while 'Jaspi', 'VVA-1', 'Julior', and 'K146-43' produced the smallest trees. Cumulative fruit yields were highest on the peach seedling, peach x almond, 'Cadaman', and 'PumiSelect' rootstocks. Lowest yields were from trees on the 'Jaspi', 'VVA-1', and 'Julior' rootstocks. Fruit weight was significantly larger on the peach seedling, peach x almond, 'Cadaman', and 'Hiawatha' rootstocks. Tree survival was low on 'Jaspi' (i.e., bacterial canker), 'VVA-1', and 'PumiSelect' (i.e., wind breakage) rootstocks. At the Columbia site, every tree on 'Adesoto 101', 'Monegro' and 'VVA-1' died from bacterial canker in the 2(nd) leaf. Many trees on 'K146-43' also died, whereas all trees on 'SC-17', 'Lovell', 'Mr.S. 2/5', 'PumiSelect', and 'VSV-1' rootstocks were alive.