History and culture of lotus.

History, varieties, cultivation and utilization of lotus.

Lotus varieties

It is a traditional cultivated variety in Beijing. Single petal pattern. The bud is peach-shaped, green, with red upper part and white flowers. The flowering period is early, starting in early June, and the group flowering period is about 1 month. Lotus roots knot early. In late July, the new lotus root turned over for the second time, and the flowering period can last until about 10. Natural variation of red lotus and pink lotus.

It is a traditional cultivated variety in Xiamen. Single petal pattern. The bud is peach-shaped, green, reddish at the top, white in pollen, and reddish at the end when it first blooms. Flowering begins in early June, and the group flowering period is 1 month. It has long and thin petals, small receptacle, many leafy flowers and easy flowering.

This is a famous variety widely cultivated. Double flower type. The buds are round peach-shaped, purple-red, with many flowers and red flowers. Flowering begins in mid-June, and the group flowering period is 1 month. Bright colors make potted plants bloom easily.

An ancient bowl lotus. Double flower type. The buds are peach-shaped, pink, with white pollen and red petals. There are many flowers, which begin to bloom in late June, and the group flowering period is 1 month, so potted plants are easy to bloom.

Breeding from Hangzhou Garden in Zhejiang Province. These plants are short. Single petal pattern. The buds are peach-shaped and green, and the flowers are small and white. Very suitable for pot cultivation. There are many flowers, and the flowering period is from mid-June to mid-August.

The history of lotus:

The scientific name of lotus is lotus, which belongs to the genus Nelumbo of Nymphaeaceae.

Lotus root It is one of the earliest species of angiosperms. According to the fossils studied by paleobotanists, lotus plants were distributed in many waters in the northern hemisphere10.35 billion years ago. At that time, in the late period of the rapid decline of the giant reptile dinosaur, its growth time on the earth was much earlier than the appearance of human ancestors (2 million years ago). According to Paleobotany (1965) by A.H. Christophevich of the former Soviet Union, lotus fossils have been found in Cretaceous strata in the Arctic of North America and amur river Basin of Asia (i.e. Heilongjiang), as well as Oligocene and Miocene strata in Europe and East Asia (Sakhalin Island) and Japan. At that time, the temperature on the earth was warmer than it is now. There were about 10~ 12 species of lotus plants distributed in five continents. With the advent of the post-glacial period, the global temperature dropped, making many plants extinct, while others were forced to drift away, completely breaking the original geographical distribution. Because of this disaster, two varieties of lotus survived, and their distribution range narrowed. Chinese lotus (Nelumbo nucifera) is distributed in Asia and northern Oceania, and N.lutea drifts to North America. Paleobotanists also pointed out that the lotus fossils from Pleistocene to Holocene (2 million years ago) excavated in Hokkaido and Kyoto are similar to modern China lotus; The lotus leaf fossils unearthed in Qaidam Basin, China, 6.5438+million years ago are similar to modern China lotus. In 1970s, China Institute of Petroleum Exploration and Development Planning, Ministry of Petrochemical Industry and Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences recorded in the book "Early Tertiary Sporopollen in Coastal Areas of Bohai Sea" that two kinds of lotus pollen fossils were found in Panshan, Liaoning, Beidagang, Tianjin, Kenli, Guangrao, Shandong and Cangzhou, Hebei. Fossils of the genus Nelumbo were also found in the strata of Changchang Basin in Qiongshan, Hainan Island, China, in the Tertiary tropical phytogeographical region. At present, the original wild lotus is still distributed in lakes and swamps in Fuyuan, Hulin, Tongjiang and Shangzhi counties of Heilongjiang Province. The above shows that lotus is an ancient plant before the Ice Age, which belongs to the representative of relict plant, such as Paeonia suffruticosa, Ginkgo biloba, Liriodendron chinense in China, Sequoia sempervirens and so on. , not swallowed by the glaciers of the ice age and survived.

Mystery of waterproof and self-cleaning of Erlianye

Numerous micron-sized waxy papillae structures are attached to the surface of lotus leaves. When observing these papillae with electron microscope, we can see that many nanoparticles with similar structures are attached to the surface of each micron-sized papillae, which scientists call the micro-nano dual structure of lotus leaf. It is these tiny double structures that make the contact area between the lotus leaf surface and water droplets or dust very limited, so there is a phenomenon that water droplets roll on the leaf surface and take away dust. Water will not stay on the surface of lotus leaves.

Scientific explanation of three kinds of fracture relations

When it comes to lotus, it is natural to mention lotus root. Holland belongs to Nymphaeaceae, a perennial herb planted in shallow ponds. Its stem was born in the mud and transformed into rhizome, that is, lotus root, also called lotus root. Lotus root grows horizontally in silt and absorbs nutrients by fibrous roots on the base stem. Lotus root has been a favorite food since ancient times, because its meat is crisp and tender, slightly sweet, contains a lot of starch and is rich in nutrition.

When we break the lotus root, we can observe that countless long white lotus roots are connected between the broken lotus roots. Why is this happening?

It is necessary to observe the structure of lotus root. It turns out that the tissues needed for plants to grow and transport water and nutrients are called ducts and tracheids. These tissues extend in all directions in plants and are as unimpeded as blood vessels in animals in leaves, stems, flowers, fruits and other organs.

The inner wall of the plant vessel will be particularly thickened at a certain position, forming various textures, some are annular, some are trapezoidal and some are reticulate. The thickened part of the lotus root catheter wall is continuous spiral, which is called spiral catheter. When the lotus root breaks, the spiral part of the inner wall of the catheter is separated and becomes a spiral filament with a diameter of only 3 ~ 5 microns. These filaments are much like stretched springs and will not break within the elastic limit. Generally, it can be stretched to about 10 cm.

Lotus root silk not only exists in lotus root, but also exists in lotus stem and lotus leaf, but is more slender. If you pick a lotus stalk, try to break it into several pieces and lift it like a long string of small green lanterns. It is this filament that connects these little green lanterns. This kind of filament looks very similar. If you look at it under a microscope, you will find that it is actually composed of 3 ~ 8 thinner filaments, just like a cotton yarn is composed of countless cotton fibers.

The delicate lingering of lotus root silk has long attracted the attention of the ancients. There is a sentence in Qufu, a poem written by Meng Jiao in the Tang Dynasty: "My heart is in the lotus root, although it is broken, it is still connected". Later, people used the idiom "broken silk" to describe that although the relationship was broken, the relationship was still connected.