Have a little knowledge of crops

1. Agricultural common sense

The new semester is coming again. In this critical period, I should carefully plan every minute and devote myself to my study. A teacher once told me that attitude is everything, and I want to face learning with a good attitude. Challenge yourself and believe in yourself. Personally, I think people's life is limited and time waits for no one, because this is the last period of my junior high school career, and I will not let everyone around me go. Earn and seize every minute around you. Looking around my study career, I think the weakest subjects are Chinese and chemistry. My strengths are math and physics. Every monthly exam has scores in chemistry and Chinese. I think I should strengthen these aspects. I think the first thing to do is to listen carefully, fully digest what the teacher said in class, and synchronize my thinking with the teacher. General textbooks are the first, and the contents in the books are the foundation. On the basis of mastering, I should do it. Fill in the blanks and improve at different levels. I also need to set up a set of wrong questions, record the wrong questions and questions that I haven't understood in practice in time, and answer them one by one to form a consolidation. In reviewing, I should advocate pragmatism, pay attention to standardization and formatting, and develop a scientific and rigorous attitude, because any nonstandard answer may lead to losing points. Because my weakest subject is Chinese, my grades are average. This composition is dull and lifeless. Read more extracurricular books after class, remember 1~2 good words and sentences every day, and practice writing according to the teacher's guidance. Try to reach 95 points or above in every composition exercise. 2. Do a good job in the exam outline and the whole product topic in advance, and prepare carefully the night before yesterday. Do more in-depth and accurate questions and expand your thinking. 3. Keep reading foreign language works every day and form good habits. Strictly avoid losing points for words in the senior high school entrance examination. Carefully review and preview the key points and appendices of the whole test center, requiring you to master grammar and sentence patterns. Pay attention to study and use it flexibly. 4. Review and recite the commonly used atomic mass table, elemental valence table, acid-base salt dissolution table, and strictly avoid losing points because of forgetting in the senior high school entrance examination. Memorize and summarize the chemical equations given by the teacher carefully, require learning and flexible use, and know the reaction conditions and results. Material constants, electricity and optics are the weakest links in my physics. I will carefully consolidate my knowledge of electricity and optics according to the teacher's general review. According to the syllabus, I will carefully review all the knowledge, finish my homework on time and take notes. 6. I will carefully review the knowledge points of history according to the syllabus, strengthen my memory in the next two months, and carefully remember the formulas and tables summarized by the teacher. Using them, I can remember the knowledge points well and pay attention to what happened this year. Connect current events with middle school history. 7. Review and recite according to the outline and the topics and knowledge points on the whole product. Because the politics of the senior high school entrance examination has become very lively this year, we should not learn by rote, we should study and use it flexibly, and we should also carefully refer to the senior high school entrance examination questions in other cities. The above study plan should be carefully implemented, and success lies in action. After a period of time, you should carefully analyze and check the current situation and the plans made.

2. What are some tips about interesting agriculture?

(A) What is pollution-free vegetables

Pollution-free vegetables refer to vegetables that are not polluted by harmful substances, and some are called green vegetables or clean vegetables. In fact, commercial vegetables do not contain toxic substances, or the content of toxic substances is controlled within the allowable range, that is, pesticide residues, nitrate content, "three wastes" harmful substances and pathogenic microorganisms do not exceed the standard. Those that meet the above standards can be called pollution-free vegetables.

With the development of science and technology and the improvement of people's living standards, the production and supply of pollution-free vegetables and green food have attracted much attention in China today. In vegetable production, people's understanding of the ecological environment has been deepened and improved. It is generally noted that nitrate in industrial pollution, pesticides and fertilizers will enter the human body through the food chain, causing certain harm and even life-threatening. Because of this, people's requirements for vegetable quality are getting stricter and stricter, and the voice of producing green vegetables is getting higher and higher. The production and supply of pollution-free vegetables are highly valued by all levels and welcomed by the masses. Therefore, using scientific methods, based on ecology, environmental protection and sociology, to produce pollution-free vegetables is not only to meet the needs of urban and rural people for clean vegetable baskets, but also related to thousands of families and even future generations.

What is green food?

Green food is a kind of pollution-free, safe, high-quality and nutritious food that follows the principle of sustainable development, is produced according to a specific mode of production, and is approved by specialized agencies to use the green food logo trademark.

(3) What are pollution-free agricultural products?

Pollution-free agricultural products refer to high-quality agricultural products and primary processed products whose safety and quality meet the relevant mandatory national standards and laws and regulations.

(4) What are the similarities and differences among organic food, green food and pollution-free food?

Organic agriculture is a growth system that is completely different from or basically does not need synthetic fertilizers, pesticides, production regulators and livestock feed additives. According to the requirements of the public, the draft standard prohibits genetic engineering technology and irradiated products from being labeled as organic food. It is a pure natural and pollution-free commodity food. It is an internationally recognized environment-friendly food. Green food is a sustainable agricultural product with China characteristics, which is based on China's national conditions and combined with the world's advanced agricultural development trend. Pollution-free food contains the basic characteristics of organic and green food, and is a transitional food of green food. They are all sustainable foods with the aim of safety, environmental protection and health, and represent the development direction of China food in the future.

3. Common knowledge of agricultural science and technology

Countermeasures of herbicide damage: improper use of herbicides will cause phytotoxicity to the next crop or adjacent crops in the current season.

Crops with serious phytotoxicity will cause phytotoxicity. Within a few hours or days, the leaves of crops with serious drug damage appear symptoms such as macular, curl, deformity and withering; Chronic type has a certain incubation period, which hinders crop growth and reduces product quality.

Other drugs have a residual period, which will affect the germination or growth of the next crop. When crop phytotoxicity occurs, the following countermeasures should be taken immediately to alleviate phytotoxicity: (1) Spray clear water: spray clear water on the leaves of people who have been sprayed excessively or nearby crops, and add 0.2% quicklime or alkaline surface to the water to wash the phytotoxicity caused by crops that are easily decomposed and ineffective when exposed to alkaline substances.

(2) Adequate irrigation can satisfy the water absorption of roots, reduce the relative concentration of drugs in crops, and achieve alleviation. (3) Spraying antidotes with properties opposite to those of harmful drugs, such as 1.8 phthalic anhydride, R-25788, etc. Neutralize and reduce the harm caused by excessive use of 2,4-butyl ester.

(4) Spraying regulators: For those with small losses, regulators such as Dynamic 2003 and Gomez can be used quickly to restore normal growth. What kind of weather is suitable for spraying pesticides? When spraying pesticides, the effect of spraying pesticides is different in different weather.

(1) Different kinds of pesticides have different temperatures that are beneficial to their efficacy. Such as dichlorvos, dimethoate, trichlorfon and ethyl ammonium phosphate, the spraying effect is better in the range of 20-30℃.

The mixture of pyrethroids and sulfur is more suitable in the range of 15-25℃. (2) When the weather is hot, you should choose to apply the pesticide when the temperature is low, preferably at 4: 00 -7: 00 pm on sunny or cloudy days, but some drugs are different, such as herbicides and hay phosphorus, and the effect is better on sunny days than on cloudy days.

The application of Bordeaux mixture on cloudy days is prone to phytotoxicity. (3) It is best to apply pesticides on windless or breezy days. If 2.4-D butyl ester is used in windy days, it will affect crops in neighboring areas and cause disputes in neighboring areas.

(4) Don't spray on rainy days or when there is dew. Because the application of pesticides in rain and dew will dilute the concentration of pesticides and reduce the efficacy.

Correct use of 2.4-D and 2.4-D butyl ester emulsifiable concentrate, 2.4-D butyl ester and 2.4-D butyl ester belong to benzene itching substances, 2.4-D butyl ester is mainly used for dyeing flowers in vegetable flowering period, and 2.4-D butyl ester is a herbicide. 2.4-D has different effects on the same crop tissue due to different doses and concentrations.

Low concentration can promote the development of fruit-setting and seedless fruit, while high concentration will cause growth deformity. Higher concentrations will kill plants and be used as herbicides.

2.4-D is insoluble in water and soluble in alcohol. Therefore, it is necessary to prepare the stock solution first, and then dilute it with water according to the required concentration. Take 1g 2.4-D powder and pour it into 5ml alcohol. After heating and dissolving, pour it into 995ml boiling water, that is, 100mg/kg stock solution, and the concentration of preventing tomato from falling is 15mg/kg, that is, take 15mg stock solution and add 988 mg of water.

The flower soaking method is to pour the prepared solution into a small cup, and then put the opened flower in the cup and soak it in the pedicel. The flower painting method is to dip the prepared solution with a brush and apply it to the flower stalk and pistil stigma. However, the concentration should not be too high when used, and it should not be sprinkled on leaves and growing points during treatment, and the treated plant fruits should not be reserved for other purposes.

2.4- Dibutyl EC is a good herbicide, which can control a variety of dicotyledonous weeds. Our district has used it for many years, and the dosage of 70% 2.4 drops of butyl ester is 50-70 grams per mu and 20-25 kilograms of water. When spraying, choose windless weather, especially pay attention to the safety of crops in adjacent plots, and the spraying equipment should be dedicated.

Prevention and control methods of root maggots of leek, onion and garlic are vegetables planted in a large area in our city, but root maggots often harm the roots and stems below the surface, causing leaves to turn yellow and wither and die. The main cause of root maggots is the use of poorly fermented raw manure, especially human manure as base fertilizer. When the temperature rises, fertilizer fermentation will attract all kinds of flies to lay eggs and produce maggots. The specific control methods are as follows: First, apply fully fermented fertilizer as base fertilizer, preferably summer fertilizer or alternate year fertilizer.

The second is to apply as much chemical fertilizer as possible. The third method is to mix 50 grams of 50% dichlorvos with 1 kg water and 2 kg wheat bran and scatter them in the field to trap and kill flies.

After the occurrence of root maggots, the root can be irrigated with 40% dimethoate 1000 times solution or 90% trichlorfon 800 times solution, all of which have good effects. Fourth, plant ash is used for prevention and control, that is, plant ash is spread all over the surface, and then plant ash and soil are mixed with a deep rake or hoe, which can prevent insects and increase production, killing two birds with one stone.

You can refer to the following methods: (1) phoxim: colorless liquid with a slightly irritating smell; (2) Killing the enemy: light yellow or brown liquid, slightly fishy; (3) Copper sulfate: Azure is alum and tasteless; (4) Carbendazim: white or grayish white powder with slight odor; (5) Mycophenolate mofetil: white powder with pepper-like smell; (6) Dixon: red solid powder foam; (7) Tobuzin: yellow powder, slightly peppery; (8) Herbicide Dan: light yellow liquid with peculiar smell; (9) Trifluralin: red liquid medicine, which turns yellow after being mixed with water; (10) bentazon: pale yellow liquid with pepper-like smell; (1 1) butachlor: light blue liquid with fragrant smell; (12) dimethoate: light yellow liquid with foul smell. Meaning of letters on pesticide labels (1) PH: indicates PH value. When the pH value is equal to 7, it is neutral, and when it is greater than 7, it is alkaline. The higher the number, the stronger the alkalinity.

It is acidic when it is less than 7, and the smaller the number, the stronger the acidity; (2) PPm: the concentration is millions. That is, 6.5438+0.0000 parts of liquid medicine, and the powder contains pesticide; (3) PC: percentage concentration: (4) Ai: active ingredient of pesticide; (5) RD: lethal dose to animals; (6) RD50: the dose that causes 50% death; (7) ED: lethal dose of sterilization; (8) B: Baume degree, that is, the dissolution of the liquid medicine is determined according to Baume degree reagent.

Generally, it is less used, so it can be seen that Pomei table; (9) MAC: maximum allowable concentration; (10) Wt: weight; (1 1) specific gravity: specific gravity; (12) S.P: water-soluble powder; ( 13)EC:EC； (14) C: particles: such as 5%C(g), that is, 5% particles. Is there a big difference between cloudy and sunny days when tomatoes are stained with flowers? Why do flowers dyed with the same concentration of 2.4-D have deformed fruits? Because in tomato dipping, the effect of dipping flowers in cloudy and sunny days is good.

Relatively speaking, it is better to touch flowers on cloudy days than on sunny days. On cloudy days, the temperature is relatively low.

4. Where is the "brief knowledge about crops"?

The whole life of wheat refers to the process from seed germination to new seed production.

The length of this stage is generally expressed by the growth period. China has a vast territory, and the natural climate conditions between the north and the south are very different, and the growth period of wheat is also different.

Autumn sowing wheat is mostly in 230-280 days, and spring sowing wheat is generally in 100- 120 days. The life of wheat has experienced a series of organ characteristics and characteristic changes.

These changes are the result of the interaction between internal genetic characteristics, physiological characteristics and external cultivation environment of wheat. The yield of wheat is finally formed in this process.

In order to better understand the law of wheat yield process, it is necessary to have a comprehensive understanding of the growth and development basis of wheat yield process. The growth and development of wheat in a lifetime can be summarized as follows: two developmental characteristics-temperature sensitivity and light sensitivity; Three growth stages-vegetative growth stage, reproductive growth stage and transition stage from vegetative growth to reproductive growth; Ten growth stages of organ formation-seed germination, seedling emergence, three leaves, tillering, getting up, jointing, booting stage, flowering, heading, ripening, and winter wheat turning green.

The typical performance period of organ formation is the emergence period of this growing period, which is usually expressed by month and day. According to different organ types, the ten organ formation stages of wheat life can be summarized into three main growth stages, namely, the vegetative growth stage dominated by long roots, stems, leaves and tillers and the transition stage between them, namely, the transition stage from vegetative growth to reproductive growth.

The growth and development process of wheat is represented by the establishment of organs. Through a series of organ construction, a complete plant structure of wheat was formed.

The basic configuration of wheat plant structure is: root-sucking part; Trunk support, transportation and storage parts; Tillering-storage branching part; Leaf assimilation part; Spike-reproductive and fruiting part. The growth process of winter wheat Winter wheat is sown in autumn and matured in the following summer. The whole growth period is generally 190~2 10 days.

From seed germination to seed production, wheat goes through the growth and development process of germination, emergence, tillering, wintering, turning green, jointing, heading, flowering, filling and maturity. After the spring, the wheat seedlings began to grow again and entered the green period.

With the increase of temperature, the growth rate of wheat seedlings is accelerated, and the internodes of stems are gradually elongated from bottom to top, which is called jointing. At this time, you can feel the obvious protruding nodes by touching the straw near the ground with your hands.

After jointing stage, the differentiated spike of wheat gradually grows upward with the elongation of internodes. When the young spike grows into the leaf sheath of the top leaf (flag leaf), the leaf sheath gradually unfolds into a spindle shape, which is called booting stage. When the last internode of the wheat straw is elongated, the top of the wheat ear extends out of the flag leaf sheath, that is, heading.

The heading date of wheat is generally from early April to early May. Flowering 2~6 days after heading.

After flowering and fertilization, wheat entered the stage of grain filling maturity.

5. Provide some suggestions on food health.

Should we choose healthy food or what is healthy? The dietary grain "miscellaneous grains" in China is healthy, and the crops referred to by "five grains" are wheat, millet, millet, millet and hemp.

When it comes to a balanced diet, we can't help but mention the nutrition pyramid; Nutritionists divide foods into four categories, namely, fat and sugar, dairy products and meat, vegetables and fruits, and cereals. The bottom of the nutrition pyramid is mainly cereals, but which agricultural products or foods should belong to cereals?

Rice and wheat are still the main foods in China. In China, rice (rice) cultivation originated in the Shennong era in southern China about 4,700 years ago. The cultivation of wheat (barley and wheat) was introduced into North China in the late prehistoric period or before Pan Geng moved to Yin.

As for the millet, millet and grain in the grain, they all belong to "millet". "Millet" is one of the important grains in the north, and it is rarely planted in the south. "Small" basically includes millet and millet.

Millet is not what we often eat today, but rice seeds and yellow rice. Corn is a crop introduced from the west only in modern times.

Peas are beans, and beans in grains are not all beans, but soybeans. Soybean was called glutinous rice in Zhou Dynasty, and it was called bean since Qin and Han Dynasties.

Hemp in grain refers to hemp. The seeds of hemp are nontoxic, but the leaves are toxic, so it can be used as food.

6. Geographical knowledge: specific mature months of crops

1, North China and its south are winter wheat, which is usually sown from the middle and late September to the early June of 10 and ripens from the end of May to the middle and late June of the following year. The southern part of the Central Plains of the United States is winter wheat, and the sowing and harvesting time is the same as that of the North China Plain.

2. Spring wheat (planted in the north of the Great Wall) is sown in the same year and harvested in the same year, so the sowing season is in spring (around the vernal equinox) and the harvest is in late summer (around the slight summer heat).

3. After harvesting wheat, soybeans should be sown at the end of June and early July, and harvested before and after the National Day.

4. Corn is divided into spring corn and autumn corn. Spring corn is sown at the end of April and early May and harvested at the end of August. Autumn corn should be sown no later than the middle of July, and harvested in the middle and late days of 65438+ 10.

5. Osmanthus fragrans in September, peach blossom in mid-April, maple leaf red from the end of 10 to165438+1mid-October.

6. Mountain pasture, grazing halfway up the mountain in summer and moving to the foothills in winter.

7. Growth conditions required by ordinary crops

Planting in humid and semi-humid plain areas

Forestry mountains or hills

Planting in humid and semi-humid plain areas

Animal husbandry in arid and semi-arid areas

Fishing lake or reservoir

Peanuts have a high demand for calories.

Rape likes cool crops, which has low requirements for soil and wide application range.

Beets have a mild and cool climate in the middle temperate zone.

Sugarcane is hot and rainy in tropical and subtropical regions.