The flowers open in the evening, emitting a sharp odor that attracts bats.
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The flowers open in the evening, emitting a sharp odor that attracts bats.
local language pauatl this plant is called tomatoes (tomati), but when it was introduced in the XVI century. in Spain and Portugal it was called the “golden apple” (pomo d’oro – hence the “tomato”).
The large family of nightshade, but as a separate subgroup includes the South American genus Cyphomandra and the Mediterranean-Asian genus Mandragora. In the genus Mandrake about 6 species, distributed from the Iberian Peninsula to the Eastern Himalayas and Tibet. Most species of mandrake are perennial grasses, almost always stemless, with very large leaves in the rosette, reaching a diameter of 1-2 m or more. Fleshy, starch-rich mandrake roots have a peculiar branching: sometimes the root gives two vertical processes and slightly resembles a human figure. Because of this feature, mandrake has long been shrouded in legends that attribute magical power to it. In addition, it contains the alkaloid hyoscyamine and in the Middle Ages was considered one of the most valuable medicinal herbs.
In Western Kopetdaz, Turkmenistan, a new species was discovered – the Turkmen mandrake (M. turcomanica). Here the vegetation of this plant begins in autumn, with the beginning of the rainy season, when it develops a rosette of large leaves. Flowering in the warm winters of the Western Kopetdag occurs in early November and lasts until mid-April. Flowers are pollinated by various insects. Fruit ripening is observed from May to late June. With the onset of a hot dry period, the plant seems to freeze and drop dried leaves. Ripe fruits of Turkmen mandrake are large (up to 5-6 cm in diameter), orange, fragrant and quite edible.
In contrast to the stemless Mediterranean species of mandrake, the Himalayan-Tibetan mandrake stem (M. caulescens) has a developed stem and smaller leaves. At the same time, its closest related species – Tibetan mandrake (M. tibetica) – is a small densely rosette plant. As can be assumed, in this case, adaptive evolution followed the path of fixing the juvenile phase of the vegetative sphere.
Further in the system of the nightshade subfamily follows a small tribe of datura (Datureae), characterized by the fact that as a result of the development of two false septa separating each of the two placentas initially dvuzhnezdnoy ovary, the ovary becomes as if four- nested. Datura fruit is a box or a berry. The most famous member of this tribe is the genus Datura, which has about 10 species of perennial or annual herbs that live in tropical and temperate countries, mainly in tropical America.
The flowers of datura species are large, with a white funnel-shaped corolla 6 to 20 cm long and more. All of them have large long-tubular flowers with a dope scent and are pollinated mainly by long-proboscis moths, which fly everywhere to smell dope, despising other plants. In the process of evolution, the elongation of the corolla tube in many members of the genus went hand in hand with an increase in the length of the proboscis of some butterflies (Sphingidae).
As a result, there were species of datura that can be pollinated only by certain species of woodpeckers, becoming completely dependent on them. Datura fruits are original prickly boxes that open with four leaves. These poisonous plants contain a number of alkaloids and are used in pharmacopoeias, and as anesthetics were known to the ancient Peruvians. In some places, dope species are cultivated as ornamentals.
In our country, the most widely known annual dope is common, or stinking (D. stramonium), which occurs as a ruderal plant in wastelands, gardens, in the fencing of buildings in almost all European parts of the CIS. They are grown as a medicinal plant in the south of Ukraine and in the Krasnodar Territory. All parts of the plant contain poisonous alkaloids (hyoscyamine, scopolamine, atropine, etc.). In the southern regions of the USSR, harmless dope (D. innoxia) native to America and dope Indian (D. metel) native to southwestern China are cultivated, the immature fruits of which contain scopolamine.
The South American genus Brugmansia, which consists of 5 species of shrubs or small trees with very large leathery leaves up to 30 cm long, is very close and often combined with datura. Huge bright tubular flowers hanging on long peduncles open in the morning, and in the afternoon, in the heat, close again, making full use of Drosophila species.
Flies gather in the corolla immediately after opening. Despite the fact that Drosophila are in the flower near the anthers, they obviously do not participate in pollination. After a few days, the corolla of the flower, inhabited by flies, falls off and with it fall to the ground adult larvae of Drosophila, continuing to feed on pollen left in the corolla. Fruit flies are likely to complete their life cycle with the flower of their sheltered face.
M. Carson, who observed certain species of Drosophila that inhabit the flowers of Brugmansia white (B. candida), believes that these species of fruit fly can exist only in coexistence with Brugmansia. The flowers are pollinated by larger insects that can penetrate the flower from the bottom up. Elongated soft or slightly woody fruits that do not open, brugmansia contain large wedge-shaped seeds. As an ornamental plant is widely known “tree dope”, which is a hybrid between Brugmansia snow and Brugmansia wood (B. arborea).
Of the other members of the tribe should be noted an extremely interesting genus Solandra (Solandra), about 10 species of which are common in tropical America. Most solander are long- and thick-stemmed vines that live in tropical mountain forests and large enveloping trees. Lifting along their trunks to a great height, the vine spreads on the top of lab report paper writing services the crown of the tree simple solid leathery leaves and exposes the sun to large beautiful, slightly zygomorphic bell flowers on thick peduncles. The multi-seeded berries of the plants, freely covered by an overgrown bright cup, are well visible from above on the surface of the crown of the host tree and are therefore willingly eaten by birds, which are carried to distant lands.condition their kidney-shaped small seeds.
Some solander individuals in old age or almost completely lose contact with the soil, continuing to function as semi-epiphytes or as true epiphytes. The most beautifully flowering species of the genus are cultivated in tropical gardens and greenhouses as ornamentals. Especially popular is the large-flowered solander (S. grandiflora), which entwines the living carpet fences and walls of houses.
Interestingly, pollination of some members of the dope tribe is carried out not only by various insects, but also by bats. This is traced to the genus Trianaea, 3 species of which are common in the mountain forests of the Northern Andes. These plants have fairly large flowers located at the ends of long hanging branches. and secrete abundant nectar. The flowers open in the evening, emitting a sharp odor that attracts bats.
The Cestreae tribe is named after the most prominent genus, Cestrum, which combines about 150 species living in the tropics and subtropics of America. These are small shrubs with solid, mostly narrow, often pubescent leaves. Their flowers, gathered in apical or axillary inflorescences of a small calyx and a long funnel-shaped or tubular corolla, open mostly at night, giving off a strong odor. The nocturnal cestrum (S. nocturnum), called “night jasmine” in the homeland, is especially different.
This shrub, widely grown in tropical gardens, forms a huge number of small greenish-white and cream flowers, which at night emit a very pleasant and strong aroma, attracting nocturnal pollinating insects. L. Overland (1960), studying the mechanism of opening and closing of flowers of “night jasmine” came to the conclusion that the substances causing their strong nocturnal smell are localized in parenchymal cells of a top of a petal.
The appearance of the smell is not the result of darkness, as might be expected, but a consequence of the internal rhythm of the plant, which does not depend on external conditions. Opening and closing of young flowers during the day is synchronized with the cycle of appearance and disappearance of the smell: wide open (at night) flowers smell, closed (during the day) – do not smell. As the flower ages, the cyclicity gradually gets lost; very old, already fertilized flowers do not smell and do not close. Some species of cestrum, such as C. campestre, are pollinated by hummingbirds. The fruits of cestrums – oblong berries.
This tribe also includes the genus Tobacco, or Nicotiana, which has 66 species, of which 45 live in non-tropical parts of America, and 21 species are dedicated to Australia and Polynesia.
These are mostly annual grasses, occasionally perennial herbaceous plants, but there are also shrubs. Flowers with a tubular funnel-shaped or bell-shaped large corolla. Hummingbirds are involved in tobacco pollination in America. The fruit is an ovoid, 2-4-leafed box filled with numerous small reticulate seeds. Plants with a severe odor. Many species of the genus contain nicotine and other toxic alkaloids. In all countries where wild tobacco lives, there have been repeated cases of poisoning by their leaves and young shoots of domestic animals.
In culture, the most well-known tobacco is real (N. tabacum) and shag tobacco (N. rustica). Shag leaves are not only used for smoking, but they are also the main raw materials for citric acid, nicotine and nicotine drugs – nicotinic acid (vitamin PP), nicotine sulfate, which are effectively used to control agricultural pests. Tobacco was grown in America long before it was discovered by Europeans. Tobacco was brought to Europe in the late XV and in the first half of the XVI century. and was originally grown as an ornamental and medicinal plant.
The genus Petunia is close to tobacco, represented by about 30 South American species; some of them are widely cultivated as ornamentals. We have the most famous hybrid petunia (P.
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