(1) watermelon
Watermelon (Thunb. Matsum et Nakai contains many types, including wild and cultivated, edible and feed species. This species includes 3 subspecies.
Subspecies 1. The hairy watermelon ssp.lanatus Fursa is called lanatus (Latin for hairy) because of its dense and fluffy plants, especially on young fruits and twigs. The vines are long, and the leaves are slightly cracked and slightly larger. The corolla is bright yellow and the petals are pointed. The flesh is compact, white or yellowish, and sometimes bitter. The top of the seed protrudes without umbilical cord.
This subspecies includes wild watermelons in southern and southwestern Africa and cultivated feed watermelons in the African continent and beyond, and is divided into three varieties.
[Variety 1] Carver Watermelon Variety (Schrade. )Mansf。 This plant grows vigorously and is hairy. The stems are thick and angular. The leaves are large, 25 cm wide, shallowly lobed, with round lobes and special smell. The flowers are large and bright yellow, and the female flowers are often bisexual. The fruit weighs 30 kilograms and is usually not straight. The stripes on the peel are not obvious, intermittent or spotted. The pulp is juicy and slightly sweet, and the content of soluble solids is 4% ~ 5%. The seeds are large, red or brown.
Watermelon, native to kalahari desert and its adjacent areas, is a wild edible watermelon with the local name "Chama".
[Variant 2] Alef. ) Fursa of Cape watermelon has long vines, and its leaves and fruits are smaller than Cafre watermelon. The flower is unisexual, the fruit is spherical, light yellow-red, with variegated stripes. The flesh is hard, white and often bitter. Seeds olive or brown.
South African (azania) Cape Province is widely distributed, hence its name. Wild weeds are common in the field.
[Variant 3] Feed watermelon variety. citrides (Bailey) mansf。 The shape is similar to Cafre watermelon, but it is neat. Flowers are usually unisexual. The fruit is cylindrical or spherical with spots or hidden flowers. The pulp is white or light yellow, dense and high in pectin. The seeds are olive red.
Widely cultivated in Britain, the former Soviet Union and other countries, most of them are used as cattle feed. Fruit can be stored for several months.
Subspecies 2. Ordinary watermelon. ) Fursa vines are long, round or angular, with sparse hair. The leaves are grayish green and tasteless, and the lobes are medium, deep or shallow. Female flowers are unisexual or bisexual, with bright yellow corolla and round petals. Fruits are very diverse in shape and color. The pulp is juicy, sweet or slightly sweet. Seeds have umbilicus. This subspecies includes cultivated and semi-cultivated watermelons all over the world, especially in subtropical and arid regions of all continents, as well as northeast Africa and west Asia.
[Variety 1] Common watermelon (var.vulgaris Fursa) with pods or circles, more than 2m long, hairy and sparse. The leaves are cracked, and some of them are mutated. Female flowers are unisexual or bisexual. The meat is red, orange, yellow or white, crisp or sandy and juicy. The content of soluble solids is 8% ~ 10%, which can reach more than 12% in some cases. The size and color of seeds vary greatly. Widely planted in 25 ~ 48 north latitude. China and the former Soviet Union have the largest arable land (Figure 22-3).
Figure 22-3 Ordinary Watermelon
1 .big watermelon 2. mini watermelon
Forsa (t.b.Ф ypca, 1965) once divided this variety of watermelon into eight ecotypes under different eco-climatic conditions and in different parts of the world. Lin Depei (1980) further divided the watermelon varieties originated in China and introduced and cultivated into five ecotypes, namely Xinjiang ecotype, North China ecotype, East Asia ecotype, Russian ecotype and American ecotype. It can be used as a reference for selecting original materials, germplasm resources and parents in introduction and breeding.
[Variant 2] The Cordoba watermelon var.cordophanus(Ter-Avan)Fursa has a long vine. The leaves are rough and crawling on the ground. Female flowers are bisexual. The fruit is spherical, with or without stripes, and the flesh is yellow. The content of soluble solids is 5% ~ 6%. Fruits rot after being stored for several months.
This variety is a common semi-cultivated plant in Sudan, ancient Egypt and Kenya. It can be used as the water source of arid savanna.
[Variant 3] Seed melon (newly proposed) var.megalaspermus Lin et Caho. The growth potential of plants is weak. Stems round and angular, slender. Leaves small, lobes narrow, deeply parted. Late ripening. The fruit is round, medium and small, and the light green peel is often covered with green walnut stripes above 10. The pulp is light yellow and white, sour and juicy, smooth and soft, and the edible quality is poor. The content of soluble solids is only 4%. The seeds are large or very large, usually light yellow at the bottom and dark brown at the edge. The 1000-grain weight is more than 250g, the grain is full and delicious. The number of single melon seeds can reach more than 200, and the yield of single melon seeds is about 65g.
This variety is a cultivated plant native to the northwest of China, and is tolerant to extensive management (Figure 22-4).
Figure 22-4 Zhengzhou melon seeds
Subspecies 3. Sticky-seed watermelon is 1.5m long, with long internodes and slender. Flower unisexuality. The fruit is spherical with a diameter of 12 ~ 14 cm. The fruit is bitter, hard or tasteless. The seeds are flat, the size of pumpkin seeds, wrapped in mucus, very unique, and the seed coat structure is diverse (Figure 22-5).
Figure 22-5 Seeds of Sticky Watermelon
Wild and semi-cultivated species native to West Africa.
Sticky seed watermelon with thin and angular vines. Leaves are shallow and prostrate on the ground, and the color is dark green. Fruit with or without stripes, hard flesh, usually bitter, and large seeds.
Wild and semi-cultivated, Nigeria and Ghana. Seeds are rich in fat and protein, and can be eaten or used for oil extraction.
[Variant 2] Senegalese watermelon var.senegalicus Fursa leaves split vertically. Female flowers, bisexual flowers. The fruit is 20 cm in diameter and striped. The flesh is white or red and edible, but it tastes light. The seed is smaller than the mucilage variety, only 0.7 cm long.
(2) Medicinal watermelon
Subspecies 1. Wild medicinal watermelon subspecies narrowmouth. ) Fursa is an annual or perennial plant, sometimes with woody roots. The vine is short, the leaves are about 10cm small, the leaves are dark green, the hairs are hard and the lobes are deep. Tendrils are bifurcated and fully developed. Flowers unisexual, small, about 2.5 cm long, petals round, light yellow. The fruit is small, with a diameter of 5 ~ 12 cm, and dries up after ripening. When the fruit is ripe, it is dark yellow, hard, white, dry, bitter and toxic. It is used as medicine to treat stomach diseases. The seeds are small, about 0.5 ~ 0.7 cm long, umbilical and brown. Distributed in North Africa-India region.
Subspecies 2. Watermelon is slender. Leaves erect, short hair. Flower unisexuality. The fruit is large, with a diameter of 18cm, and is often irregular polygon. When it is mature, it is striped ochre red. The pulp is white or rose red. It tastes light and sometimes bitter. The seeds are larger and sometimes have umbilicus holes (Figure 22-6).
Figure 22-6 Medicinal Watermelon
Tunisia, Algeria, Egypt and Jordan, Mediterranean countries in North Africa and West Asia.
(3) Watermelon without beard
Perennial plants with woody roots. The vines are about 3m long, round or angular, thick, with sparse and hard hairs, and the internodes are 13 ~ 15 cm long. The leaves are small, about 6 ~ 8 cm, deeply divided, wrinkled and smelly, and semi-prostrate. There are often no tendrils in the natural state, but there are tendrils under artificial cultivation, which are divided into 2 forks. Flowers unisexual, about 3.5 ~ 4 cm long, petals yellow, round. The fruit is about 15 ~ 17 cm in diameter, polygonal, gray-green, with dark stripes. The flesh is white, hard and bitter. The seeds are small, wide and dark brown.
This is a wild plant, which grows in Endermont, Namibia, South Africa.
(4) Nuodan Watermelon
Perennial, dioecious, with thick roots. The vines are thin, 3 ~ 4m long and almost bare. Leaf blade is small, about 6 ~ 8 cm, rough, deeply divided to the base, and the lobes are narrow and long. Tendrils do not diverge and degenerate into thorns. The flowers are unisexual, the corolla is bright yellow, and there are short thorns on the ovary and fruit. The fruit is oval and has a tumor on the surface. The fruit is small, 6 ~ 12 cm long and 4 ~ 8 cm wide. The peel can be peeled off like an orange, the meat can be eaten, and the taste is sweet and sour. The seed is smooth, white, 0.8cm long, with a special seed coat structure and multiple layers of stone cells under the skin, which is extremely difficult to germinate (Figure 22-7).
Figure 22-7 Nuodan Watermelon
It is distributed in Angola, Zimbabwe, Zambia, Mozambique and transvaal province. It is a wild plant with high disease resistance, and the common diseases on cultivated watermelon are not infected with this variety.