Pearl of Csaba

Main Characteristics

The grape variety Zhemchug Saba was bred in 1904 by the breeder Stark in Hungary through the sowing of seeds of unknown origin. Regarding its direction of use, it is positioned as a very early table grape variety. The full vegetative period from the beginning of budburst to the onset of harvest maturity of the berries takes 113–115 days, requiring a sum of active temperatures within 2087 °C to complete the cycle. The harvest maturity under the conditions of southern regions occurs in the first half of August (from August 1 to August 15). The vines are characterized by medium vigor, while demonstrating good maturity of one-year-old shoots (80–85% and more). The average yield of the grape variety Zhemchug Saba varies significantly depending on the conditions and the type of training system: it amounts to 38.7 centners per hectare in a semi-covered culture, reaches 47.3 centners per hectare in a covered culture, and can range from 85.7 to 98.7 centners per hectare under irrigation and at specialized state testing plots (with maximum rates up to 113 centners per hectare).

The clusters are of medium size, conical or cylindro-conical in shape, and are characterized by a relatively loose structure or medium density. The average bunch weight is 117 g. The rounded berries are colored yellowish-green. The berry skin is thin, tearing, and covered with a weak, easily erased waxy bloom. The pulp has a juicy and delicate texture with a highly pronounced and pleasant muscat aroma. The average weight of 100 berries is 170 g, and each berry contains 1–2 small seeds. The sensory evaluation score of the fresh product is 7.6 points. The sugar accumulation in berry juice ranges from 14 to 18 g/100 ml, with titratable acidity levels of 6.5–8.5 g/l.

Morphological Description of the Grape Variety Zhemchug Saba

• Young shoot (tip): The tip of the young shoot has a light green or distinct yellowish-green coloration with characteristic wine-red edges on the young leaves.
• Young leaves: The first and second leaf blades have a bronze-reddish tint. Pubescence on the lower side of the young leaf is araneose, becoming sparse and bristly as it ages, localizing mainly on the veins.
• One-year-old mature shoot: It is characterized by a light brown coloration with dark brown highlighting of the nodes.
• Formed leaf: Leaves are medium in size, with a 5-lobed structure, a shallow degree of lobing, and a wavy surface. The leaf blade features a peculiar curvature in which a part of the leaf opposite one of the lateral sinuses is raised. Pubescence on the lower side of the formed leaf is weak and bristly.
• Leaf incisions and sinuses: Upper and lower lateral sinuses are small, open, and slot-like. The petiole sinus is in most cases open, vault-shaped (arched), with an elliptical opening.
• Teeth: The teeth at the ends of the leaf lobes are triangular. The marginal teeth along the edge of the leaf blade are also triangular, with weakly convex sides.
• Saplings: Saplings form semi-prostrate shoots with a bronze tip and small, practically entire leaves of a light green color. The autumn color of the leaves turns a pure yellow.

Agrotechnical Features

The grape variety Zhemchug Saba is successfully cultivated both in a high-stem culture (trunk height 70–120 cm, vine spacing 3 × 1.5 m) and with a stemless fan training system (vine spacing 2.5 × 1–1.25 m). The bud load per bush is set within 35–40 live buds, which corresponds to 27–30 shoots left after debris removal (shoots thinning). The recommended pruning length for fruit canes is medium. The most preferred soils for cultivation are chernozems, as well as dark gray loamy and light loamy soil types, well-provided with moisture and nutrients, on which the vigor of the vines increases significantly with the application of fertilizers. Depending on specific soil and climatic conditions, Berlandieri × Riparia Teleki 5 C, SO4, and Riparia × Rupestris 101-14 are recommended as the best rootstocks.

The share of fruitful shoots on a vine is 48%. The fruiting coefficient is 0.56, while the fruitfulness coefficient reaches 1.37. An additional advantage of the variety is the ability of fruitful shoots to develop from replacement and dormant buds, which allows for partial crop recovery after damage by spring frosts. Every year, the phenomenon of berry shotting (millerandage) is observed in the grape variety Zhemchug Saba. The mechanical properties of the berries are low: the average separation force is 375 g, and the crushing resistance is 419 g, which makes the harvested grapes poorly adapted to long-distance transportation. Due to very early ripening and thin skin, the berries are frequently and heavily damaged by birds, honeybees, and wasps, which dictates the necessity of a quick harvest and immediate realization of the collected crop.

The variety is moderately affected by downy mildew (mildew) and shows high sensitivity to powdery mildew (oidium), requiring timely preventive treatments. At the same time, the grape variety Zhemchug Saba is practically immune to berry damage by gray rot (botrytis) due to its very early harvest before the onset of prolonged autumn rains. The foliage can be heavily damaged by spider mites. The overall frost resistance indicators of the variety slightly exceed the standards for most other table varieties of Eurasian origin.