Six-Year Performance of 14 PrunusRootstocks at 11 Sites in the 2001 NC-140 Peach Trial

Abstract

Fourteen Prunusrootstock cultivars and selections budded with either �Redtop�, �Redhaven� or �Cresthaven� peach [ Prunus persica(L.) Batsch] were planted at 11 locations in North America in 2001 in a randomized block design with a tree spacing of 5 by 6 m and 8 replicates. This test planting was an NC-140 Cooperative Regional Rootstock Project ( www.nc140.org). There were 14 rootstocks in total, which included three peach seedling rootstocks: Lovell, Bailey, and Guardian� �BY520-9� [selection SC-17]. Clonal rootstocks included the peach � almond hybrids BH-4 and SLAP (Cornerstone); peach � plum hybrids K146-43 (Controller 5), K146-44, and P30-135 (Controller 9); interspecific plum hybrids Hiawatha, Jaspi and Julior; interspecific Prunushybrids Cadaman� and VVA-1 (Krymsk� 1); and Prunus pumilaL. selection Pumiselect�. Final tree size was largest in California, Georgia, Maryland, and South Carolina. BH-4, SLAP, SC-17, Lovell, and Cadaman� were the most vigorous rootstocks. Jaspi, K146-43, K146-44 and VVA-1 were the least vigorous, having trunk cross-sectional areas 20-50% of Lovell-rooted trees. No rootstock had a significantly higher survival rate than Lovell at all locations, but Bailey, K146-44, and P30-135 had good survival at all test sites. Julior and Jaspi consistently produced root suckers. Pumiselect� had anchorage problems at several locations. Cumulative fruit yields were highest on the peach seedling, peach � almond, and Cadaman� rootstocks. Lowest cumulative yields were from the small trees on Jaspi, VVA-1 and K146-44 rootstocks. Fruit weight did not differ much among rootstocks though cultivars on Pumiselect� and K146-43 often had smaller fruit. Cumulative yield efficiency was not consistently related to tree size. Rootstocks influenced dates of bloom and harvest, but not in a consistent manner across locations/cultivars.