The production of plant adventitious roots and adventitious buds

Bamboo shoots, wheat node tips growing

Endosperm development and callus formation

Interphase: replication of DNA molecules and synthesis of related proteins

Prophase: the nuclear membrane and nucleoli disappear, chromatin turns into chromosomes, and spindles appear

Metaphase: The chromosome shape is stable, and the number of centromeres is clear and arranged on the equatorial plate.

Anaphase: The centromere is divided into two, the number of chromosomes is doubled, evenly distributed and moved to the two poles of the cell.

Telophase: nuclear membrane and nucleolus appear, chromosomes turn into chromatin filaments, and spindle disappears

Meiosis I

Meiosis II

⑴, epidermis

⑵. Periderm: including cork cambium, cork layer and cork inner layer

⑴, absorbing tissue

⑵, assimilation organization

⑶, storage tissue

⑷, ventilatory tissue

⑴, thick angle tissue

⑵, thick wall tissue

⑴, ducts and tracheids

⑵, Sieve tubes and companion cells

⑴. Exocrine structures: glandular trichomes, glandular scales, nectaries, drains

⑵ Endocrine structure: secretory cells, secretory chambers, secretory tracts, and milk ducts

⑴. Root types: Source: main root and lateral root. Location of occurrence: Definite and adventitious roots

⑵, root system

⑴. Primary structure: epidermis, cortex and central column from outside to inside

⑵ Secondary structure: from outside to inside: periderm, cortex, phloem, cambium, xylem and rays.

⑴. Root nodules: formed by nitrogen-fixing bacteria and actinomycetes. Rhizobium is characterized by nitrogen fixation

⑵, mycorrhizae

Long branches: vegetative growth

Short branches: reproductive growth

birth position

Scale-like metamorphic leaf bud scale that protects the outside of the bud

Organs: branch buds, flower buds and mixed buds (apple).

erect stem (redwood)

Twining stems (bean, honeysuckle, morning glory, wisteria)

Climbing stems: (luffa, cucumber, grape, green bean, ivy, nasturtium) Climbing stems can be: tendrils (loofah), aerial roots (ivy), petioles (nasturtium), Barbs (pig pests), suckers (creepers). Plants with twining and climbing stems are collectively called vines

Stolons (sweet potato, strawberry)

branch

Tiller: and the branching method of family plants (rice, wheat)

nascent structure:

Secondary structure: from outside to inside, they are periderm (cork layer, cork cambium layer, cork inner layer), cortex, primary phloem, secondary phloem, Cambium, secondary xylem, primary xylem, pith, etc.

Economy: ① as wood ② as weaving raw material ③ as textile ④ as chemical raw material ⑤ as food ⑥ as ornamental

⑴Type of leaves

⑵Leaf shape

⑶Leaf tip

⑷Leaf margin

⑸Pulse sequence

⑹Phyllotaxy:

⑴The structure of dicotyledonous plant leaves: composed of three parts: epidermis, mesophyll, and veins

⑵The structure of grass plant leaves: epidermis, mesophyll, and veins

Physiology: photosynthesis and transpiration, absorption and reproduction

Economy: edible, medicinal, industrial raw materials, production of fertilizers, feed, and beverages.

storage root

aerial roots

parasitic root

Aboveground stem metamorphosis

Underground stem metamorphosis

Scale leaves: onions, lilies

Bract leaves: corn, sunflower

Leaf thorns: black locust, cactus

Leaf Tendrils: Pea

Pitcher plant: Nepenthes

Petiole shape: Acacia tree

⑴Pedicel and receptacle

⑵Calyx and corolla: The calyx and corolla are collectively called the perianth. It has the function of protecting the pistil and stamens.

⑶ Stamen group: composed of anthers and filaments. The anther is the swollen, sac-like part at the top of the filament. Mature anthers contain a large number of pollen grains.

⑷Pistil group: Located in the center of the flower, it is the general name for all the pistils in a flower. Each pistil is composed of stigma, style and ovary. The stigma is It is made up of rolled carpels, which are metamorphosed leaves adapted to reproduction. The enlarged top part of the pistil can accept pollen. The style is the pollen grains in the column It is the basic unit that makes up the pistil. The passage through which the head enters the ovary after germination. The ovary is composed of ovary wall, placenta, and ovule. The ovule is the precursor of the seed.

Xiaosui

Infinite inflorescence

Limited inflorescence (cyme or centrifugal inflorescence)

⑴The development of stamens

⑵ Development of pistil: The most important part of pistil is the ovary.

⑴Blooming: The calyx and corolla are about to open, and the pistils and stamens are exposed. Flowering is a sign of sexual maturity in most plants. ①Blooming age ②Blooming period: The time it takes for a plant to complete from the first flower to the last flower. Wheat 3 to 6 days, pears and apples 6 to 12 days, rapeseed 20 to 40 days

⑵Pollination

⑶ Fertilization: The process in which male and female gametes fuse with each other to form a zygote.

⑷Apomixis and polyembryony

⑴ Development of the embryo: It develops from the zygote. After fertilization, the zygote goes through a period of dormancy before it begins to develop. (4 to 6 hours for rice, 16 to 18 hours for wheat, 2 to 3 days for cotton, 5 to 6 days for apples, and 5 to 6 months for tea trees.

⑵ Development of endosperm: The endosperm of angiosperms develops from primary endosperm and often has triplicate chromosomes

⑶ Development of seed coat: The plant integument develops into a seed coat, which is located outside the seed and plays a protective role.

Embryo: four parts: embryo, hypocotyl, radicle, and cotyledons

Endosperm: stores nutrients (starch, fat and protein) for the nutritional needs of the seed during germination

Seed coat: wraps around the embryo and endosperm to protect it.

Endospermless seeds: composed of seed coat and embryo, such as beans, melons, cabbage, radish, peach, and pear in dicotyledonous plants. Seeds of arrowheads and Alisma in monocotyledonous plants.

Endosperm seeds: seed coat, embryo, and endosperm are composed of three parts, such as castor, buckwheat, eggplant, tomato, pepper, grape seeds, and monocot seeds such as cereals, onions, and garlic.

Seed vitality: refers to the potential ability of the seed to germinate or the vitality of the embryo.

Seed viability: refers to the ability of seeds to germinate quickly and neatly in the field and form strong seedlings, including germination potential, growth potential and production potential.

The life span of a seed: the longest period of time that a seed can maintain its vitality under certain conditions. The longer the seed is stored, the weaker its vitality will be, and may even lose its vitality completely. The main reason why seeds lose their vitality is due to the destruction of enzyme substances and the disappearance of stored nutrients, which leads to the decline and death of embryonic cells. Seed storage must be kept dry and cool. If the temperature is too high, the seeds will also lose their vitality.

The germination process of seeds: through three stages: imbibition, germination and germination.

Conditions for seed germination: First of all, it depends on whether the seed itself is viable. External factors: appropriate moisture, appropriate temperature and sufficient oxygen. Some seeds also need light to germinate (lettuce, carrots)

After-ripening effect: After the seeds leave the mother body, they undergo a series of physiological processes before they reach physiological maturity and thus have the ability to germinate. This is most obvious in wheat seeds. The water absorption rate of wheat is more than 30%, and that of corn is 45 to 50%. Within the suitable temperature range, as the temperature increases, the seed germination speed accelerates, and there are three basic points of minimum, maximum and optimum temperatures for seed germination. Generally, plant seeds require an oxygen concentration of more than 10% to germinate normally. Seeds with an oxygen concentration below 5% cannot germinate.

Fruit: composed of peel and seeds enclosed in the peel

Peel: endocarp, mesocarp and exocarp.

True fruit: developed from the ovary (walnut)

False fruit: In addition to the ovary, the receptacle, calyx or inflorescence axis are involved in the formation

Single fruit: a fruit formed by only one pistil in a flower, divided into fleshy fruit and dry fruit

Aggregate fruit: There are many small fruits formed in Huato

Juhuaguo: The fruit develops from the entire inflorescence, also known as compound fruit.

Indole derivatives: indolebutyric acid (IBA), indolepropionic acid (IPA), indole ester (IZAA).

Derivatives of naphthalene: naphthaleneacetic acid (NAA), methyl naphthaleneacetate (MENA), naphthaleneacetamide (NAD)

Derivatives of halogenated benzene:

Application in production

Triiodobenzoic acid (TIBA): It is mostly used in soybeans to increase branches, increase flower bud differentiation, increase pod setting rate, and increase yield.

Methylamine (MH): widely used in storage of potatoes, onions, and garlic to prevent germination

Plastic hormones can eliminate the geotropism and phototropism of plants. In production, it is mostly used for woody plants to shape woody bonsai.

Chlormequat (CCC): a commonly used growth retardant. Spraying on dwarf trees can shorten the internodes, shorten the stems, thicken the stems, and deepen the leaf color, which is beneficial to improving the light transmission conditions of the flora. Enhance photosynthesis and resist lodging, suitable for cotton, wheat, corn, rice, peanuts, tomatoes, fruit trees and other crops

Compared with (B), it inhibits cell division of the meristem tissue at the top of fruit trees and slows down the growth of branches. It can replace artificial planting to increase the number of flowers and fruits in the next year. And prevent pre-harvest fruit drop and promote fruit coloring. It is mainly used in crops such as peanuts, fruit trees, soybeans, cucumbers, tomatoes and vegetables, and is used as a dwarfing agent, fruit setting agent, rooting agent and preservative.

Paclobutrazol ( ) slows down cell division and growth, resulting in thicker stems and dark green leaves. Suitable for use in cereals, especially rice fields

Mepidamine ( ): The auxiliary agent is mainly used in cotton and can also be used in wheat, corn, peanuts, tomatoes, melons, and fruit trees.