MAXMA DELBARD 14 brokforest (P. mahaleb x P. avium)
Clonal selection from an open pollinated population of Prunus mahaleb. Probably a hybrid of Prunus mahaleb x Prunus avium. Originated in Oregon, USA, patend. Plants in the nursery show medium-high vigour and have a semi-spreading habit. The root system grows well both vertically and horizontally, and plants have excellent anchorage in the soil. Grafting compatibility with sweet cherry varieties and performance of the plants in the nursery are very good; high taking rates are obtained with summer budding (T and chip), winter grafting, and spring budding (T and chip) with growing buds. Plants grafted on this rootstock are about 20% more vigorous than those grafted on CAB 6P and about 30% less vigorous than those grafted on cherry seedlings. It is suitable for soils with good drainage and for semi-arid areaswith high evaporative demand and low rainfall; resistant to high lime soils; not suited to heavy soils. Medium susceptibility to Phytophtora cactorum and to Verticillium dahlae; sensitive to Armillaria mellea, tolerant to Pseudomonas syringae and to Agrobacterium tumefaciens. Tendency to suckering is low and depends on soil management practices. All cherry varieties grafted on MAXMA14 show earlier cropping, higher yield efficiency and better fruit quality in comparison to those grafted on seedling rootstocks. Suitable for specialised orchards, possible irrigated, of medium or medium-high (600-800 trees/ha ) density.
MAXMA DELBARD 60 broksec (P. mahaleb x P. avium)
Clonal selection from an open pollinated population of Prunus mahaleb. Probably a hybrid of Prunus mahaleb x Prunus avium. Originated in Oregon, USA, patented. Trees in the nursery are vigorous and have an upright growing habit. The root system is well-developed both vertically and horizontally; strong roots are thickly covered with hairs and anchorage is excellent; no suckering. Plant vigour is between ‘SL 64’ and ‘F.12.1’. Young trees in the nursery are slightly more vigorous than ‘SL 64’. Good taking rates are obtained with summer budding (T and chip), winter grafting both in the nursery and at the bench, and with spring budding (T and chip) with growing buds. The best period for bud grafting is early summer. Grafting compatibility is good with the main sweet cherry varieties tested. Plants grafted on this rootstock are 10-20% more vigorous than those grafted on cherry seedlings. Adapts to a wide range of soil conditions; grows well even in dry and limestone soils. Resistant to P hytophtora cambivora and P. megasperma and tolerant to Pseudomonas syringae. This is a rustic clonal rootstock which can be an interesting alternative to Prunus mahaleb and Prunus avium seedlings, especially for cherry cultivation in less favourable pedoclimatic conditions. Excellent grafting compatibility and yield efficiency. Suitable for specialised orchards of low or medium-low (300-400 trees/ha) density.