Cuban Spur

Winter apple variety of intensive type, selected by the North Caucasus Regional Institute of Horticulture and Viticulture, developed through clonal selection using induced mutagenesis, following exposure to cesium-137 radiation on vegetative buds of the 'Cuban' variety in 1969. Breeder: S. N. Artiukh.

Introduced into the State Register of Selection Achievements of Russia in 1997, approved for use in the North Caucasus region. Present in commercial orchards and home gardening, began spreading across southern Russian regions and Ukraine.

Main clonal variation — suppression of growth processes, which resulted in a 20-25% reduction in crown parameters: height, diameter, and density of scaffold branches. This created conditions for crown openness and improved aeration. The latter factor, along with its altered genotype — triploid (the 'Cuban' variety is mixoploid) — contributes to disease resistance: whereas the original 'Cuban' variety was affected by scab in the 1990s epidemics with more than 4 points on both leaves and fruits, 'Cuban Spur' is affected only by 1.5-2 points. The nature of this variation positively influenced crown illumination: enhanced fruit color, dessert quality, and increased bioactive potential, along with significant resistance to storage diseases.

Tree is low-growing, with a compact, small-crowned form; young trees have an oval crown, while after 8 years it becomes broadly oval, moderately dense, and well-leafed. Main branches have light brown-gray bark, emerging from the trunk at a sharp angle and upward. Fruit-bearing type is mixed: whorls (60%), spur-type, starting from five-year-old wood; one-year-old shoots are generally fruiting.

Shoots of medium thickness, curved, with shortened internodes, brownish-green, densely hairy. Leaves, like in the original variety, are large, broadly oval, with an oval base often with unequal lobes, small but distinctly pointed tips; smooth and slightly curved, but strongly folded and spirally twisted. Color is light green. Hairs are moderate, strong on young leaves. Leaf margin is doubly toothed, with large waves. Leaf blade forms an acute angle with the petiole. Petiole is often colored, thick, stipules are awl-shaped or absent. In the nursery, stems are curved, light green with yellowing on the southern side, with large rounded light-colored stipules, very short internodes, and white tufts of young leaves at the tips similar to the original variety and its presumed ancestor — 'Wagner'. In 'Cuban Spur', as in 'Wagner', the color contrast between upper and lower leaf surfaces is stronger compared to petioles.

Flowers are dish-shaped, white with a pinkish tint, with a long hairy style and stigma positioned at the level of stamens. Flowering is medium-early.

Fruits (see photo) are less large than in the 'Cuban' variety, averaging 170 g, moderately flattened, round-conical. Ridging is usually absent. Main color at harvest is greenish, with a more intense blush than in the original variety — bright red with carmine tones covering most of the fruit, darker streaks on the diffuse blush and remaining fruit surface. Skin is dense but thin, oily in storage, developing a rusty net pattern due to application of copper-containing protective agents at the fruit set. Calyx tube is of medium width but deep, mostly without rusting. Pedicel is of medium thickness and length, and only on side fruits it protrudes from the calyx tube. Calyx is broad, of medium depth, with slight rugosity. Receptacle is half-closed. Receptacle tube is funnel-shaped, unlike the 'Cuban' variety. Axial cavity is less voluminous than in the original variety, and seed chambers are narrower than in 'Cuban', although they are open through a narrow slit.

Flesh is light cream-colored, dessert-like slightly tart-sweet flavor, dense, becomes tender in storage, aromatic. Best-tasting fruits and those that store well come from orchards with zinc application. Chemical composition of fruits: dry matter — 11-14%, sugars — 9-10%, titratable acids — 0.5-0.7%, ascorbic acid — 15-20 mg/100 g, total P-active substances — 90-110 mg/100g.

Harvesting of fruits in the central part of the Krasnodar region occurs in mid-September. Under normal storage conditions, fruits retain their consumer qualities until March. If harvesting is delayed, fruits drop due to wind. Fruit commercial quality is high — 90%.

Fruits have high nutritional value and produce excellent processed products: juices, jams, chips.

Self-sterile; best pollinators: Golden Delicious, Renet Simirenko, Wagner.

Trees begin fruiting in the second year after planting. By the 5th year, on low-growing rootstocks, with planting density of 1000 trees/ha, yield is 150 centners/ha; by the 10-12th year — 400 centners/ha. Enhanced agroclimatic conditions, specific pruning forms, and suitable rootstocks can increase yield to 500-600 centners/ha.

'Cuban Spur' trees are winter- and drought-resistant in southern conditions.

Advantages of the variety: high ecological adaptability, intensive type — small crown, ultra-early fruiting, high yield without sharp periodicity in fruiting, high commercial quality and medicinal properties of fruits.

Disadvantages of the variety: requires protection from scab and fruit borers. Incompatibility with copper-containing agents.

In breeding, 'Cuban Spur' is known as a donor of low-growing habit, high yield, commercial quality, and fruit quality and vitamin content. The variety served as a parent form for new varieties in the North Caucasus: Luch, Vadimovka, Persikovoe, etc., as well as some varieties in Ukraine.