A new unique hybrid watermelon of the Crimson Sweet type with super early maturity.
A new hybrid of mid-early maturity (80-85 days since sowing). The vigorous fruit cover protects it from the sunburn.
Botanical and biological features
Watermelon (Citrullus vulgaris Schrad.) is an annual herbaceous plant belonging to the Cucurbitaceae family.
The watermelon root system formation begins prior to emergence of cotyledons to the soil surface and reaches maximum extension by the time of flowering. Watermelon features a highly branching tap root extending up to 1 m deep into the soil. Some 15, occasionally more, lateral roots run from the main root. These, in turn, branch into smaller roots, resulting in an extensive root system which normally threads 7–10 m3 of soil 15 to 30 cm deep in the topsoil.
A characteristic feature of the watermelon root system is its great suction force which is capable of drawing water from soil at 6% humidity and even from dry sands of Karakum desert. The suction pressure of watermelon seedlings may be as high as 1 MPa (10 atm.).
This explains why watermelon plants are drought resistant and capable of growing on poor sandy soils. The watermelon stem is a long trailing vine reaching, in some seasons, five and more meters in length, highly branched, forming secondary side shoots which, in turn, branch. The vines, especially the younger shoots, are covered with long wooly hairs protecting the plant from overheating. Initially, the vegetative biomass develops very slowly while the root system expands aggressively. Twenty to thirty days after emergence of seedlings, the plants grow rapidly, form vines and start flowering, provided the weather conditions are favorable. During this period, the overall shoot elongation occurs at a rate of 2 m per plant per 24 h. The watermelon is a monoecious plant with diclinous flowers. Depending on the variety, the watermelon seeds vary in shape, size and color. Germination occurs at 15–16˚C. The optimum growth temperature is 25–30˚C. A drop in temperature to 15˚C causes growth retardation, whereas prolonged exposure to temperatures of 5–10˚C is injurious to the crop. Seedlings die at a temperature of -1˚C. In spite of being a drought-resistant plant, watermelon requires large quantities of water, especially at the initial stages of development. Irrigating 2-3 times during flowering and fruit setting results in a considerable increase in yield. The optimum humidity in the 0–70 cm soil layer is 75–80% of field moisture capacity (FMC), whereas the optimum relative air humidity is 50–60%. Higher air humidity cause growth retardation, a longer growing season and lower sugar content.
The watermelon is very sensitive to light conditions. In dull and cool weather, the growth is arrested. Watermelons respond well to fertilizer: phosphorus and potassium speed up fruit ripening and increase sugar content.
To prevent the Fusarium and other pathogens from building up in the soil, a 7–8 year crop rotation should be strictly observed.
Sowing normally takes place when soil at a depth of 5–8 cm has warmed up to 12–15˚C. The planting pattern is 180–200 x 60–80 cm. The seeding depth is 4–5 cm in irrigated soil and 6–8 cm without irrigation. The seeding rate is 16–25 seeds per 10 m2 (1,0–3,0 kg/ha). The recommended fertilizer application rates are: 20–30 kg per 10 m2 (20–30 ton/ha) of organic fertilizers and 800 g of nitroammophoska (16-16-16) per 10 m2 (N 130, P2O5 130, K2O 130 kg of active substance per hectare). It is advisable that the organic fertilizers and 2/3 of the mineral fertilizers be applied in autumn and the remainder – as supplementary fertilizing during the growing season.
Fertilizer application rates are adjusted according to the nutrient status of the soil. Depending on the area and growing conditions, 2 to 7 irrigations are given to the crop with a water application rate of 300–350 l per 10 m2 (300–350 m3/ha) per irrigation.
Combining drip irrigation with application of water-soluble fertilizers through the drip irrigation system (fertigation) is a highly efficient technique resulting in a more uniform moisture and fertilizer distribution in the root zone, more efficient water use, less soil compaction, and no soil crust formed. Readily soluble mineral fertilizers are given with each water application. Th
e most damaging watermelon diseases are Anthracnose, Bacteriosis, Fusarium wilt and Powdery mildew.
Control measures: strict adherence to the crop rotation program, seed treatment, planting resistant varieties, spraying plants with Previcure against downy mildew and treating plants with fungicides, as instructed on the product labels, to control the other diseases.
Major pests: cotton aphid, thrips, spider mite and, occasionally, cutworms. Insecticide sprays such as Arrivo, Fufanon, Fury and Sherpa are used to control cotton aphid and thrips. Spider mites can effectively be controlled with acaricides.