Patent Analysis of Plant Growth Regulators in China (I)

Patent Analysis of Plant Growth Regulators in China (I)

Registration management of plant growth regulators in China and formulation of limit standards (I)

Plant growth regulators refer to a class of substances in plants that regulate growth and other functions. Plant growth regulators have a variety of uses. It can be said that they can be used to regulate the germination, rooting, leafing, flowering and fruiting of seeds, as well as the preservation and storage of fruits and vegetables after harvest. It is mainly divided into three categories: auxin, cytokinin and gibberellin.1、 Registration of plant growth regulators in ChinaChina promulgated and implemented the Regulations on the Administration of Pesticides in 1997 and revised it in 2001 as the basic law on pesticides, which uniformly manages plant growth regulators as pesticides. At present, there are not many varieties of plant growth regulators registered in China. However, in agricultural production, plant growth regulators are widely used, ranging from bulk food crops such as soybeans, corn, rice, wheat, potatoes, to various economic crops such as vegetables, flowers, fruit trees, etc., in rooting, shaping, defoliation, inducing resistance, improving fruit setting, controlling growth, promoting growth, ripening, preserving, and increasing yield Plant growth regulators play an important role in improving quality.A total of 33 registered active ingredients have been obtained, including gibberellic acid, meperidate, ethephon, naphthoic acid, chlormequat, sec-butylene, thiazolone, monocyandiamide, S-inducin, chloranilide, propionyl brassinolide, brassinolide, antidepressant, butyrylhydrazide, uniconazole, paclobutrazole, enaadenine, hydroxyurea purine, silycycline, Yiyadan, indoleacetic acid, triacontanol, flubenamide, dimethoxypentyl, clopidomide 1-methylcyclopropene, hypersensitive protein, calcium cyclamate, nucleotides, potassium dinitrate, prochloraz, 24-drop sodium salt, 24-drop triethanolamine salt.2、 Exemption list of plant regulators and pesticide residuesAt the ninth meeting of the 8th National Pesticide Registration and Review Committee, in accordance with the relevant provisions of the Provisions on Pesticide Registration Data, and in reference to international practices, seven plant growth regulators were exempted from the maximum residue limits, namely: gibberellic acid, enaadenine, 6-benzylamino-purine, hydroxyenaadenine, hypersensitive protein, and S-attractant acid, Triacontanol.3、 Key points for review of registration residue data of plant growth regulators1. Data of residue reduction testThe application or explanation for reducing residue test data confirms that the product has been officially registered on the crop for more than six years and has complete residue test data. Whether the product registration number, pesticide name, dosage form, registered crop, dosage (not more than 1.5 times) and use method of the cited enterprise are consistent with the enterprise.2. Conditions and 3 conditions for authorizing residue report2.1 Conditions to be met: The authorized residue test report shall comply with the provisions of the Regulations on Pesticide Registration Data and the Guidelines for Pesticide Residue Test and other policies. According to the Regulations on Pesticide Registration Data, the applicant "must provide the authorization of the registered reporter who independently has the same effective ingredients, dosage forms, scope of use and method data", and must also provide the authorization statement and complete residue test report of the authorized enterprise, and the authorized enterprise must have obtained the registration authorization to be effective.2.2 There are three cases of authorizing residue data: residue data can be authorized between single agent and single agent with the same effective ingredients; Residue information can be authorized between mixtures with identical active ingredients; The single-agent residue data can be authorized to the mixture containing the same active ingredient and the content is not higher than this single agent.3. Review points of residue test report3.1 Evaluate whether the field test design scheme is reasonable according to the Provisions on Pesticide Registration Data and Pesticide Residue Test Criteria.3.2 Evaluate whether the residue analysis and detection method is feasible.3.3 The safety interval is recommended according to the registered application dose and times, and the residual test results are evaluated.Field design of residue test1. Requirements for test pointsIt shall meet the requirements of Annex 2 of the Provisions on Pesticide Registration Data: more than two years and three places for bulk crops; More than one plot of small crops in two years; Other crops are planted for two years.2. Arrangement principle of test pointsThe representative main planting areas and planting methods are tested; The main planting areas should have sufficient spacing; The planting area should select different climatic zones and soil types for testing; Two years and two places - select the north and south according to the main planting areas; Two years, one place - limited by climate, planting area and planting mode.3. Area and quantity of field test plotsIn principle, it should comply with the requirements of the Guidelines for Pesticide Residue Test (NY/T 788-2004). Vegetables shall not be less than 15 square meters per plot; Grain shall not be less than 30 square meters per plot; At least 2 fruit trees are required; The number of cells is set to 3; A protection line is set between the cells.4. Dose and times of applicationThe final residue test dose is 1.5 times the recommended dose of the enterprise; The application times are the recommended application times and one more application times; Application period and interval5. Collection interval settingIt shall be set according to the provisions of 5.3 of the Guidelines for Pesticide Residue Test. It should conform to the growth characteristics of crops and actual production conditions. Generally, there should be more than 2 recovery intervals. The harvest interval of cucumber, tomato, tea and other crops should be shorter, set as 1, 2, 3, 5, 7 days; The harvest interval of cotton, rice, citrus and other crops can be longer, set as 7, 14, 21, 28 or 30 days.6. SamplingIt shall meet the requirements of Appendix A Crop Classification, Sampling Location and Recommended Sampling Amount in 7.2.1 of the Guidelines for Pesticide Residue Test, and the crop location to be tested shall include the edible part of the crop. The emergency shall be recorded and explained. (World Agrochemical Network)

What is ethephon? What is the application prospect?

The growth and development of higher plants depend on roots to absorb water and inorganic substances from the soil, carbon dioxide and light, and some organic substances such as protein, sugar and fat. In addition, it also requires the organic substances with high physiological activity produced by the plant itself. Although the content of the organic substances is very small in the plant body, they play a very important role and can directly affect the growth, development and metabolism of the plant. If the plant lacks it, it can not grow normally, or even survive. Such organic substances with high physiological activity are called plant hormones. Plant hormones are the normal metabolic products of plants. Different plant hormones are produced by different tissues and organs, and then transported to other organs, which play an important role in regulating plant growth. Some important links in the process of plant growth, such as germination, rooting, seedling emergence, growth, organ differentiation, flowering and bearing, maturity and aging, organ shedding, seed dormancy, are all regulated and controlled by plant hormones.After decades of research, there are five major categories of plant hormones that have been found and recognized, which can be divided into two aspects according to their physiological functions: promoting growth and inhibiting growth. It is of great significance for people to understand and study plant hormones to master and control plant growth, improve quality, overcome adversity and even increase yield.The distribution of five major hormones in plants is uneven. Auxin, gibberellin and cytokinin mainly exist in the young parts of plant tissues, such as the tip of stem and root, young fruit and young seed; Abscisic acid and ethylene mainly exist in the aged tissues, exfoliated organs and mature fruits of plants. The content of plant hormones in the plant body is not invariable, such as the change of wheat from heading to filling, the amount of cytokinin in the wheat ear after heading is large, the content reaches the peak at the end of flowering, followed by gibberellin, and reaches the high level three weeks after flowering, the content of auxin begins to increase four weeks after heading, and decreases at maturity.Because the content of plant hormones in plants is very small, it is impossible to extract them from plants and apply them in production. Now people can synthesize substances with physiological activity by simulating the chemical structure of natural hormones in plants with chemical methods, or synthesize substances with physiological activity that are completely different from the chemical structure of natural hormones. These substances have similar effects of plant hormones and can also play a role in regulating plant growth and development. These substances are collectively called plant growth regulators or chemical regulators.Plant growth regulators can generally be divided into two categories. One is to promote plant growth and development, such as naphthoic acid for promoting rooting, gibberellin for breaking dormancy, and 6-benzyladenine for preventing aging. These are called stimulants; The other type is called inhibitor, which can inhibit the growth and development of plants, such as CCC, which can prevent cotton and wheat from growing crazily, and cyanogen, which can prevent garlic, onion and potato from sprouting.However, this method is not absolute, because the same growth regulator can be used as a stimulant at low concentrations and as an inhibitor at high concentrations. For example, naphthoic acid can stimulate the growth of rice seedlings at dozens of PPM concentrations, but 1000ppm concentration can inhibit the growth of rice seedlings; For example, 2,4-D, 10-20ppm concentration can promote growth and prevent abscission, 100ppm will inhibit plant growth, and 1000ppm will kill dicotyledons. In addition, different plants and even different organs of the same plant have different responses to growth regulators. For example, auxin is generally sensitive to roots, followed by buds, and stems are less sensitive. At the same concentration, it can promote the stems, but may inhibit the roots.So why is ethephon a plant growth regulator? This starts with the role of ethylene. A long time ago, people found that a kind of gas emitted from rotten fruits can accelerate the ripening of surrounding fruits. In the early 1930s, it was confirmed that the effective component of the gas released from fruit was ethylene, which was a natural substance. Later, it was further discovered that the roots, stems, leaves, flowers, fruits and other organs of plants can produce ethylene. Ethylene is produced by fruit and promotes fruit ripening. The relationship between fruit ripening and ethylene naturally attracted people's attention. By the 1960s, the use of gas chromatography, which can detect very small amounts of ethylene, deepened people's understanding of ethylene. It is not only related to fruit ripening, but also related to plant cell division and expansion, seed dormancy and germination, flowering, sex differentiation, aging Important physiological processes such as abscission are closely related. Ethylene is a normal metabolite of plants, widely exists in plants, and plays a very important role in regulating plant growth, development and metabolism. Therefore, ethylene is recognized as an endogenous hormone of plants.Although ethylene has a wide range of regulatory effects on plants, its application is limited due to its inconvenient storage, transportation and use as a gas. Later, it was found that ethylene could be produced from ethephon. Ethephon can release ethylene under certain conditions (such as alkali). Ethephon can be mixed into a certain concentration of water solution to spray or soak the plant, so that Ethephon can be decomposed in the plant to produce ethylene, and then play a role in regulating the growth and development of the plant, which can be considered as Ethephon is a plant growth regulator. In fact, the use of ethephon on plants is a convenient method of applying ethylene to plants.Since 1968, ethephon has been used as an ethylene release agent in the research of plant growth regulators. In 1971, the Shanghai Institute of Plant Physiology of the Chinese Academy of Sciences and Shanghai Pengpu Chemical Plant, the Beijing Institute of Botany of the Chinese Academy of Sciences and the Second Beijing Pesticide Plant, and other units simultaneously carried out the synthesis and research of ethephon. In the same year, it was tested on rubber, and the obvious effect of increasing production of rubber latex was first obtained. Since then, many units in the country have carried out a lot of experimental research and demonstration and promotion work, so that the research and application of ethephon have made great progress in both depth and breadth.There are varieties of crops that use ethephon in agriculture in China, including cash crops such as rubber, Qinshu, pine, cotton, tobacco, tea, kenaf, jute, rape, beet, grass, tulu incense, Indian rosewood, sugarcane, moso bamboo, wutong, etc; Gardening crops such as tomato, banana, pineapple, orange, watermelon, persimmon, peach, apple, apricot, pear, litchi, grape, hawthorn, jujube, chestnut, cucumber, gourd, melon, pumpkin, pepper, spinach, etc; There are more than 40 kinds of food crops, such as rice, wheat, corn and sorghum. The trial crops are more extensive than other growth regulators. It has been proved through repeated practice in various places that ethephon can increase the rubber discharge and yield of rubber and raw materials; Ripening of bananas, tomatoes and other fruits and cotton; Dwarfing of rice and maize; Cucumber and gourd induce more female flowers; Wheat emasculation; Tea flower removal; Jujube and hawthorn have significant effects in accelerating the fall. At present, cotton, rubber, rice and other crops with large area of ethephon are used in agricultural production in China. The application of ethephon in cotton was listed as a national key extension project by the Ministry of Agriculture in 1980, and has received good economic benefits through large-scale use. For this reason, he won the second prize of the Technology Improvement Award of the Ministry of Agriculture in 1980 and the Technology Promotion and Application Award issued by the National Science and Technology Commission and the Agriculture Commission in 1982.Although the research on the application of ethephon in agriculture has only a history of more than ten years, it has developed rapidly. It can be believed that ethephon will play a greater role in promoting China's agricultural production in the future.

High-yield cultivation techniques of peanut

Peanut is also known as groundnut, long-fruit, long-fruit, golden peanut, ground bean, Chinese bean, etc. Peanut is an annual herb belonging to the butterfly-shaped flower family. It is native to South America. There are more than 100 countries cultivating peanuts in the world, and it is common in Asia, followed by Africa. Nowadays, it is planted all over the country, mainly in Liaoning, Shandong, Hebei, Henan, Jiangsu, Fujian, Guangdong, Guangxi, Guizhou, Sichuan and other regions. Taking the northern summer peanut as an example, the peanut plant protection management work from pre-sowing to harvest in each month will be listed by month.1、 Pre-show preparation period1. Field management indicators: site selection, fertilization, seed selection and seed treatment(1) Site selectionTry not to repeat. After the harvest of the previous crop, the stubble shall be shallowly ploughed and removed in time, generally 10-17cm, raked and ridged for planting, and the quick-acting fertilizer shall be applied in time after the emergence of seedlings. For intercropping peanuts on the wheat ridge, deep ploughing and fine raking shall be conducted before wheat sowing, and deep ploughing shall be more than 26 cm, and organic fertilizer shall be applied. Generally, the ridge height is 17 cm, the ridge distance is 33-40 cm, and each row is sown. Sow as you rise to prevent moisture from affecting seedling emergence.(2) Apply sufficient basic fertilizerThe application amount of peanut base fertilizer should generally account for 70% - 80% of the total amount of fertilizer, mainly composed of decomposed organic fertilizer, combined with superphosphate, potassium chloride, lime and other inorganic fertilizers. Nitrogen, phosphorus and potassium of base fertilizer can be applied at the ratio of 1:1:2.(3) Selected seedsBefore sowing, select seeds, remove unqualified seeds such as diseased seeds, loquat seeds and rotten seeds, and select sunny days to sun seeds for 1-2 days.(4) Seed coating and chemical seed dressingThe main control targets are root and stem base diseases, such as crown rot, root rot, stem rot and cyst nematode. Pay attention to the prevention and control of underground pests such as squid, white grub and golden needle worm. The seeds can be mixed with fungicides, pesticides and plant growth regulators or coated with seeds.2. Chemical weedingSpraying pre-bud herbicide on the ground after sowing and before emergence of peanut can effectively control weeds.2、 Seed germination and seedling stageFrom sowing to 50% of the seedlings are unearthed and the first true leaf is unfolded, which is the seedling stage for seed germination.1. Field management indicatorsIn cultivation, it is required to sow the whole seedlings at one time, and the seedlings should be even.2. Main cultivation technical measuresTimely clear the trees or break the film to release the seedlings, check and reseed the seedlings, and prevent the frost damage. In combination with the weather conditions, each mu can be equipped with the application of polyphenols, prochloraz DA-6, s-inducer and other regulators to enhance the resistance and cultivate strong seedlings.3、 Seedling stageFrom the seedling stage to 50% of the first flower of the plant opens at the seedling stage.1. Field management indicatorsPreserve seedlings, promote roots and strong seedlings, promote early flowering and multiple flowers, strive for multiple nodes and dense branches, and lay the foundation for high yield.2. Main cultivation technical measures(1) Fertilization: the absorption of nitrogen, phosphorus and other nutrients is not much at seedling stage, but at the seedling stage, due to the obvious acceleration of plant growth, the nutrients brought by the seeds have been basically exhausted, and the root nodules have not yet formed. Therefore, proper application of N and P at seedling stage can promote the development of nodule, facilitate nitrogen fixation of rhizobium, significantly promote the number of flower bud differentiation, and increase the number of effective flowers. It is suggested that at this time, in combination with the law of peanut fertilizer demand, calcium nitrate and potassium dinitrophosphate should be sprayed on the leaves, and one or two regulators such as sodium nitrophenolate, prochloraz DA-6, brassinolide, triacontanol, chlormequat, and paracetamol should be selected to promote root and leaf growth and cultivate strong seedlings.(2) Pest and disease management: The main prevention and control disease in this period is leaf spot disease. Each mu is sprayed with fungicides such as mancozeb or prochloraz manganese salt, combined with regulators such as sodium nitrophenolate, to improve the efficacy and restore the seedling vigor. The pest control is aphid, which can be spray with imidacloprid, nitenpyram, etc4、 Flowering and needling stageThe flowering and needle setting period is from the beginning of flowering to the emergence of chicken head shaped young fruit in 50% of plants.1. Field management indicatorsPromote early flowering and more flowers, strive for multiple nodes and dense branches, and lay the foundation for high yield.2. Main cultivation technical measures(1) Fertilization management: The absorption of N, P and K is about 23-33% of the total absorption. At this time, a large number of nodules are formed, which can provide more and more nitrogen for peanuts. It is suggested that potassium fertilizer, calcium fertilizer and boron fertilizer should be applied on the leaves to supplement the nutrient needs of fertilizer deficiency during this period.(2) Pest and disease management: disease management should continue to focus on preventing leaf spot and peanut rust. Spraying fluosilazole or prochloraz manganese salt per mu, combined with spraying sodium nitrophenolate or prochloraz, and spraying once every 7 to 10 days will have better effect. At the same time, due to the rise of temperature, attention should be paid to the prevention of peanut dwarf virus disease, and attention should be paid to the prevention and control of aphids in planting. If a virus disease hazard is found, it can be effectively prevented and reduced by combining with aphid control and spraying nitrosamoline guanidine and other anti-virus agents per mu.5、 Podding stageThe podding stage is from the appearance of young fruit to the appearance of full fruit in 50% of plants.1. Field management indicatorsControl flourishing, resist lodging, prevent leaf disease, spray boron outside the root, increase fruit weight, and improve fruit bearing rate and full fruit rate.2. Main cultivation technical measures(1) Fertilization management: nitrogen and phosphorus absorbed in this period account for about 50% of the total amount of the whole growth period. Ensuring the supply of calcium in this period can improve the rate of full fruit; Ensuring the supply of phosphorus can improve the oil content of seeds. Calcium nitrate and boric acid can be sprayed on the leaves, and the use of fresh amine ester can promote the root and fruit expansion, and increase the photosynthetic efficiency of leaves. At the same time, it is necessary to choose to use calcium cyclamate, paclobutrazol and other regulators to control overgrowth.(2) Pest and disease management: the main control diseases in the pod stage are leaf spot and rust. At this time, attention should be paid to continue spraying fluosilazole or prochloraz manganese salt in combination with foliar fertilizer per mu. In addition, the wheat stubble peanut is in the high temperature rainy season, and the peanut bacterial wilt is very easy to occur after the heavy rain. At this time, attention should be paid to spraying agricultural streptomycin and other chemicals to prevent the occurrence of bacterial diseases. In the area with serious underground pests, 40% phoxim emulsifiable concentrate or 40% methyl isocarbophos emulsifiable concentrate mixed with fine soil can be used to make toxic soil per mu. Before plowing, evenly spread the ground and plough it into the soil. The effect of using phoxim or methyl isocarbophos microcapsules is better.6、 Full fruit maturityThe period from 50% of the plants to most of the pods is full fruit maturity.1. Field management indicatorsProtect functional leaves, prevent lodging, prevent premature aging, spray phosphorus and potassium fertilizer, promote the transfer of stem and leaf nutrients to pods, improve the content, and increase fruit weight.2. Main cultivation technical measures(1) Fertilization management: the water consumption and fertilizer demand in the second full fruit period decreased. If there is no compensation capacity in case of drought, the full fruit period will be shortened and the yield will be reduced. At this time, attention should be paid to spraying phosphorus and potassium fertilizer in combination with leaf surface, and spraying sodium compound nitrate, DA-6, 6-BA and other regulators at the same time to improve leaf function, accelerate the conversion of carbohydrates into fat, and prevent physiological defoliation of leaves.(2) Pest and disease management: the ripening stage of full fruit is the late stage of peanut growth, at which time the number of leaf spot and rust sources has accumulated to a large value, and the control agent is mainly to reduce the number of spores. It is better to spray manganese zinc oxysporin or prochloraz manganese salt per mu, combined with growth regulators such as sodium nitrophenolate or prochloraz.7、 Proper harvest and storage with shell1. Proper harvest(1) According to plant growth;(2) According to the full fruit rate: 80%;(3) According to the change of temperature or the requirements of peanut post-planting.2. Storage with shellThe safe storage moisture content of pods is 10%.

Compound technology of several new plant growth regulators

Human beings pay more attention to ecological and environmental security, and biotechnology is growing stronger, which all add a threshold to the development of new plant growth regulators. Therefore, the current thinking of plant growth regulator technical drug development is changing and adjusting. In terms of new product development, more attention is paid to expanding the application space of old varieties with the help of new technologies, including the following four directions:1. Development of new products with low toxicity and low residue, such as calcium cyclamate, anti-vinegar and other products;2. The development and improvement technology of biological pesticides, such as the biological fermentation technology of s-inducin, and the improvement of the persistence of brassican vinegar;3. New technologies for the preparation and processing of old products, such as brassican vinegar soluble powder, regulator sustained-release agent and other technologies;4. Utilize the complementation and synergism between the active ingredients to develop the compound products of the regulator.Here, we introduce several new composite products.1、 Gibberellin+benzylaminopurine (GA4+7+6-BA)Benzylamine · gibberellic acid is a compound plant growth regulator, which can be absorbed by the stems, leaves and flowers of plants, and then transmitted to the active part of meristem to promote fruit setting. The preparation has 3.6% and 3.8% contents, and has two dosage forms of emulsifiable oil and soluble agent, diluted 600-800 times, and used respectively in the blooming period of apple and 15~20 days after the application. This mixture is an effective plant growth regulator. Benzaminopurine can promote cell division and flower bud differentiation; GA. - 7 is an important endogenous hormone to promote plant growth and development. It can promote stem elongation, break dormancy, and promote fruit setting. The combination of the two can significantly improve the fruit type, increase the fruit setting rate and increase the yield. It can promote the growth and development of plants, correct and beautiful fruit shape. From the perspective of its physiological function, this mixture can not only improve the fruit setting rate, remove rust, and improve the yield and quality of apple series fruit trees, but also be used for fruit trees such as bananas, grapes, mangoes, pears, melons such as watermelon, loofah, cucumber, tomato, pepper, eggplant and other solanaceous crops, and also can be used for cut flowers, potted flowers and other crops. It is a combination of fruit setting, fruit swelling Multi-functional products such as prolonging flowering period. Therefore, this product has a very broad prospect of promotion and application.2、 Gibberellin+indoleacetic acid+brassinolideThe preparation is 0.136% Chi. Indo. Brassica wettable powder, 3.5~14g/mu, mainly used for tea, cucumber, apple tree, wheat and other types of crops. This mixture is a pure natural plant-derived product, containing gibberellin, indoleacetic acid, brassinolide and other plant endogenous hormones as well as flavonoids, amino acids and other active substances. It can promote root development, promote chlorophyll synthesis, induce flower bud differentiation, enhance plant growth, improve crop quality, improve crop resistance to drought, cold, frost and disease, and relieve fertilizer and drug damage. It is a fully functional pharmaceutical product. This product still has broad prospects in promotion and application, and is a good product to be popularized.3、 Potassium indobutyrate+s-inducerThe preparation is 1% wettable powder, diluted 500~1000 times, mainly used to promote rooting in rice seedling fields. The inducer is a natural substance in plants and a product of microbial fermentation. Its main function is to induce plants to develop resistance to adverse environment. It is well known that the development of biological pesticides (including biological regulators) is an inevitable choice to improve the environmental quality and ecological safety of agrochemical products. The development and industrialization of biological regulators will play an increasingly important role in the field of regulator research, and will become one of the technical support of pollution-free agriculture.4、 Tefenone+ethephonThis mixture is mainly used for cotton drying. It can be used when the cotton naturally opens its bolls 60-70%, and the effect is fast. The cotton stops growing in 24 hours, dies in 3 days, and basically dries up in 7 days. It is the efficient cotton desiccant currently used in China. In recent years, it has gradually replaced the paraquat+ethephon mixture to avoid the side effects of dead cotton leaves without falling off, cotton peach ossification and affecting cotton picking by machine. According to a large number of experimental and research data, the use of thiophene in combination with ethylene to accelerate the ripening of cotton will cause all cotton leaves to fall off for mechanical cotton picking. Most of the major cotton production bases in foreign countries use machinery to pick cotton. China's machinery picking has just begun. With the increase in the value of labor force, machinery picking will be the inevitable direction of China's development, and Thi · B will also be one of the promising plant growth regulators.5、 Other viable composite productsSodium naphthylacetate+sodium indobutyrate, its dosage form is 50% soluble powder, and its concentration is 10-2000mg/L, which is mainly used for cutting rooting and transplanting rooting. It is an older product with significant efficacy. With the development of agricultural industrialization, this product will continue to glow with vitality.Promoter. It is mainly used to control the growth and shoot of fruit trees. Promoters are used in combination with the control products to avoid the side effects of fertilizer loss and premature aging caused by excessive control. With excellent performance, it has become a more widely used direction of plant growth regulators.Sodium nitrophenolate+DA-6, its mixed preparation can be water, powder, granules and other models. It is an excellent compound preparation that has become a conventional preparation in the past 10 years. Its superior quick-acting, long-acting and safety have been recognized by everyone, and it still has its place in the future regulator market.6、 ConclusionChina's agricultural production is facing problems such as food security, ecological security, frequent occurrence of biological and abiotic adversity, etc. How to ensure the sustainable development of China's agricultural production and improve the competitiveness of agricultural products in the field of cultivation has become the primary task of crop cultivation discipline. At this time, it is particularly necessary to review and summarize the achievements of crop chemical control and continuously improve its technical level. Making full use of the existing varieties of pesticides and plant growth regulators to produce new products is an important task for us at present, and it will also become a major trend. We should seize this opportunity to develop our agrochemical products, otherwise, once the world's agrochemical industry undergoes major changes, China's agrochemical industry will face the risk of being forced out of the market.

Main problems in the use of plant growth regulators

The efficacy of plant growth regulators is affected by many factors, such as crop variety, growth cycle, application site, regulator variety, application concentration, application method and external natural conditions. Therefore, there are high requirements for the use technology of plant growth regulators. Once there is an error, it may cause pesticide damage to crops and cause unnecessary losses. The problem of drug damage is a prominent problem in the use of plant growth regulators. Common drug damage mainly includes the following reasons:1. Incorrect usage periodThe use of plant growth regulators is subject to strict requirements. Once the application period is inappropriate, it will cause drug damage, which may result in reduced production in the light and no harvest in the heavy.Case 1: Application of Timuride on WatermelonIn late May 2011, the "Japanese all-around champion" watermelon of Liu Mingxu, a villager of Dalu Village, Yanling Town, Danyang City, Jiangsu Province, burst due to the use of "watermelon expander".People are accustomed to think that puffin is the culprit that causes watermelon to crack. In fact, watermelon cracking is not caused by the use of watermelon expander. Watermelon expander itself is not a problem, but because it is used in an incorrect period of use. The main component of watermelon expander is clopidomide, also known as clopidomide and KT-30. Its correct use period is to dip the melon embryo at the concentration of 10-20mg/L on the day or one day before and after the flowering of watermelon, which can play the role of expanding watermelon, increasing sugar content, reducing the number of melon seeds, uniform melon shape, and beautiful appearance. When the diameter of watermelon is more than 15cm, it can't be used again, otherwise it will cause drug damage, specifically manifested as hollow watermelon, loose gourd gourd gourd, decreased sweetness, poor taste, and more serious, it will lead to watermelon cracking. At the same time, because clopidomide is not conductive, it is easy to cause abnormal melon if it is not evenly stained. The melon grower used watermelon expander at the wrong time, not only did not play the role of clopidomide, but also caused drug damage.Case 2: The application of chlormequat in cottonIn the middle of June 2010, a cotton farmer in Handan, Hebei, said that the cotton he planted would not grow when it grew to 20 cm high, forming a stiff plant. After detailed inquiry, we learned that it was caused by the incorrect period of application of chlormequat. CCM has a good effect on controlling cotton growth and promoting high yield of cotton. The correct use period is to spray 100~200mg/L of CCM when the cotton grows 6~7 fruit branches, which can effectively control cotton growth, make the main stem of cotton stretch slowly, plant dwarf, fruit branches shorten, and plant type compact, which is conducive to ventilation and light transmission in the field, promote cotton photosynthesis, and increase yield significantly. However, when the cotton plant just grew to 20 cm, the cotton farmer saw that the cotton plant was growing vigorously, and sprayed 150 mg/L of chlormequat, which caused the cotton to stop growing, resulting in stiff plants.2. Incorrect dosageThe dosage of each plant growth regulator is strictly limited. If used low, the effect will not be achieved. If used high, the drug damage will occur.Case 1: Application of sodium nitrate and naphthoic acid in peach treesIn May 1998, a fruit farmer in Shandong Province used 2.85% sodium nitrate and naphthylacetic acid on the peach trees in the greenhouse, causing all the young peach trees in the six greenhouses to fall off, and some even the leaves to fall off. The reason for this phenomenon is that the use concentration is incorrect. When spraying 2.85% sodium nitrate and naphthoic acid aqueous solution at the young fruit stage of peach, it should be diluted by 4000 times to spray the whole plant, which can play the role of expanding fruit, beautifying fruit and improving taste. However, the fruit farmer only diluted by 1500 times when using it, and the use concentration is too high, resulting in all the young peaches falling off, and the six greenhouses are basically out of harvest..Case 2: Coloring application of ethephon on grapes.In 2010, a fruit grower in Mianyang, Sichuan reported that the grapes he planted fell off before they were fully mature. Ethephon has a good effect on promoting grape coloring. Different grape varieties have slightly different concentrations. For example, Jufeng grape can ripen 6 to 8 days earlier by spraying the ear at a concentration of 250~300mg/L at the beginning of ripening, and the uniform color is good. However, the use of ethephon will cause separation between grains and fruit stalks, which will lead to seed falling. Therefore, it is necessary to grasp the concentration, spray, harvest and sell in stages to avoid losses. The fruit grower blindly expanded the use of concentration, and uniformly sprayed 500 mg/L of ethephon on grapes of different varieties and different growth periods, resulting in a large number of seed falling.3. The dosage of plant growth regulators on different crop varieties is differentBecause different crop varieties have different sensitivities to the growth regulation of the same plant, the plant growth regulator should be tested before being popularized.Case 1: Application of NAA on different varieties of watermelonIn 2009, a melon farmer in Nanjing reported that the watermelon leaves turned over overnight after spraying 10 mg/L of NAA when the diameter of the watermelon was about 10 cm.Naphthylacetic acid is a good flower and fruit preserving and expanding agent. It is one of the early plant growth regulators used in China. In the 1960s, China began to synthesize and use naphthylacetic acid, which plays a great role in cotton flower and boll protection, fruit tree flower and fruit thinning, flower and fruit thinning. The use of 10mg/L naphthylacetic acid on cotton, most fruit trees (except peach trees) and melons (except watermelon) can play a role in flower and fruit preservation, fruit expansion Watermelon is sensitive to the effect of coloration. The high concentration is 8mg/L. If the concentration is more than 8mg/L, the damage will occur. When the concentration is 10-15mg/L, the watermelon leaves will reverse. When the concentration is 15-20mg/L, the watermelon will wilt. When the concentration is more than 20mg/L, individual watermelon varieties will die. The farmer sprayed the melon at a concentration of 10mg/L according to the instructions, ignoring the particularity of watermelon, which led to the phenomenon of watermelon leafing.Case 2: Application of prochloraz DA-6 in different peach varietiesIn 2007, more than 10000 mu of peach trees were planted in a certain area of Dalian, and a concentration of 10mg/L of prochloraz was uniformly sprayed during the young peach period. The results showed that the effect of prochloraz on flat peach and long-lived peach varieties was significant, but the leaves of nectarine appeared bean-size spots. After the test, it was proved that the concentration of prochloraz DA-6 in nectarine was 6mg/L, and the leaf spots would appear when the concentration of prochloraz DA-6 was 10mg/L.Dichloraz is a broad-spectrum plant growth regulator with a long period of use. It can be used for seed soaking, seedling, growth and flowering spraying. It is safe to use. There have been no reports of pesticide damage of Dichloraz. We have found that only when the concentration exceeds 50mg/L, the growth of some varieties of crops will be inhibited.4. Incorrect use methodWhen the same plant growth regulator is applied to the same crop, it will also cause drug damage if it is used improperly.Case 1: Application of clopidomide KT-30 on zucchiniIn December 2008, vegetable farmers in Shouguang, Shandong Province reported that all the zucchini they planted in the greenhouse had deformed melons, all of which were gourd-shaped, with big heads. It was found that it was caused by improper use of clopidomide. The correct way to use clopidomide on zucchini is to soak the melon embryo with a concentration of 10mg/L when the zucchini blooms for 1 to 2 days, which can play an obvious role in fruit expansion and fruit homogenization, so as to market early. The melon was dipped with the liquid medicine in a disposable paper cup. Due to the small mouth of the cup, only the lower part of the melon embryo was stained when dipping the fruit. Due to the non-conductivity of clopidomide, the cells in the stained part split quickly and expanded rapidly, and the non-stained part continued to grow normally. Therefore, all the pickled zucchini grew into gourd shape, with a large head.Case 2: Application of gibberellin in grapesIn 2006, some fruit farmers in Turpan, Xinjiang, reported that the use of gibberellin in grapes planted by them resulted in very uneven grains, which seriously affected the yield and quality. After investigation, it was caused by improper use of gibberellin. The application of gibberellin on grapes has significant effects on enlarging ear length, increasing fruit grain, early ripening, increasing sugar and fruit acid content, and its performance is also relatively stable. The correct use method is to dip the ear with 150mg/L concentration 10~20 days after the full flowering of grapes. The farmer sprayed the ears with a spray, which resulted in large grains on the treated ears and small grains on the untreated ears. Grape grains on the same ear were large and small. Grape grains on different ears were also different in size, seriously affecting the yield and quality of grapes.5. Use at willThe compound application technology of plant growth regulators has been verified through strict formula screening and field tests, and can play a synergistic role. For example, 2.85% sodium nitrate. naphthylacetic acid aqueous solution, 30% ammonium salt. ethephon aqueous solution and so on are all good compound preparations of plant growth regulators, but not all plant growth regulators can be combined.Case 1: The wrong application of the compound of sodium dinitrophenol and thiofenone on flammulina velutipesIn 2006, some vegetable farmers in Luoyang reported that the 5-mu goldenrod they planted sprayed with sodium dinitrophenol and thiophene at the same time during the blooming period, resulting in the withering and withering of goldenrod.Spraying 6~9mg/L sodium nitrophenolate on the goldenrod can increase the flow of cytoplasm, promote the absorption and operation of other chemicals and fertilizers in the crop, make the flowers even and fat, and play a role in increasing production; Spraying 1 mg/L concentration of thiabenduron can make the plant robust and reduce flower bud shedding. However, the combination of the two can produce side effects such as wilting and withering and even killing the goldenrod under adverse climatic conditions.Case 2: The wrong application of the combination of chlormequat and acetaminophen in cottonIn 2010, some farmers in Hebei reported that the 10 mu cotton they planted grew grew slowly and the petiole became brittle after being sprayed with chlormequat and chlorhexidine at the same time.Both chlormequat and acetaminophen can promote the slow extension of cotton main stem, dwarf the plant, shorten the fruit branch, and make the plant compact, which is beneficial to the ventilation and light transmission in the field, promote the photosynthesis of cotton, and increase the yield. However, when the two are used in combination, they can only play a role in controlling the growth and yield within the appropriate concentration range. The farmer used the normal concentration of chlormequat and chlorhexidine on cotton at the same time, resulting in the cotton stop growing and the petiole become brittle.6. Other non-standard drugsDifferent use methods, time and concentration of the same agent will play different roles. If it is used wrongly, it will cause harm. For example, paclobutrazol is used on apple trees. When the apple trees have grown into productive plants, the growth of apple trees in the second year can be effectively controlled by applying 2~3g paclobutrazol to the roots around 1.5 meters around the tree for one week in autumn, which is still effective in the third year; When the apple treetop grows to 5~10 cm, the growth of the apple treetop can be controlled by spraying with a concentration of 300 mg/L; The growth of the current year's shoots can be controlled by scraping the bark of the trunk 20~30 days after the flowering of the apple tree in the Spring Festival and brushing the trunk with a concentration of 1000mg/L, which is still effective in the next year. If the usage and dosage are not correct, it will have no effect or even cause drug damage. For example, spraying 1000 mg/L paclobutrazol on apple trees will seriously hinder growth, lead to yield reduction and fruit quality decline.Environmental conditions also directly affect the use effect of plant growth regulators. For example, if the temperature is lower than 20 ℃ or higher than 35 ℃, the effect of naphthoic acid on tomato fruit preservation is not good; When the temperature is 25~30 ℃, the wrapping effect is very good. Another example is that clopidomide should be used on the day when the cucumber blooms. If it is used on the day when the cucumber has reached about 10cm in length or later, the cucumber placed in the refrigerator is still growing, but the taste is poor and the quality is decreased.

What is the reason for the poor efficacy of pesticides in the field

At present, pesticide spraying is still the main method to control crop diseases and insect pests. However, in production practice, it is often encountered that the efficacy of qualified pesticides is not ideal. The reasons are as follows:Cause 1: medicine is not rightFirst, treat diseases as pests, treat insects as diseases, and use drugs incorrectly. For example, if the dead seedlings caused by tomato bacterial wilt are misdiagnosed as the dead seedlings caused by the root biting of underground pests, no matter how many drugs are used, they will not be effective.Second, although the diagnosis is correct, the medication is not correct. For example, Jinggangmycin was used to control rice blast, dicofol was used to control wheat aphid, and dicofol was used to control rice planthopper.Reason 2: bungling the opportunityFor pest control, the effect of pesticide application is good at the peak of adult oviposition or before the 3rd instar of larvae. If the larva is more than 3 years old, the effect will be poor no matter how much pesticide is applied.Cause 3: inaccurate dosageToo much medicine is easy to cause drug damage, and too little medicine can not achieve the purpose of disease and pest control. Therefore, it is necessary to prepare according to the pesticide application instructions to obtain satisfactory control effects.Reason 4: improper mixingIf the weak acid or neutral pesticides such as dimethoate, phoxim and dichloromethane are mixed with basic pesticides such as sulfur mixture, it will cause pesticide decomposition and failure; The mixture of alkaline pesticide sulfur mixture and Bordeaux liquid will produce excessive soluble copper, which will cause drug damage.Cause 5: blind sprayingSpraying should be sprayed on the key parts to achieve the desired effect. For the prevention and control of sunflower sclerotinia disease, it should be sprayed on the field before sclerotinia germination according to the rule of sclerotinia overwintering in the soil. The control effect is only good. If the drug is sprayed on the diseased part, the effect is not good. Rice blast, bacterial leaf blight and other diseases mainly occur on the leaves. When applying drugs, spray on the leaves; In order to control cotton red spider, it is necessary to spray the medicine on the back of the leaves to achieve good control effect.Cause 6: adverse weatherThe efficacy is closely related to meteorological factors such as temperature, humidity, rain, dew, wind and light. If emulsion pesticide is applied, the effect will be good if there is no rain for at least the next 24 hours after spraying. It takes at least two days for the application of stomach poison and contact pesticide to have a good effect. Therefore, it is necessary to choose fine weather for spraying according to the local weather forecast.Reason 7: poor quality of medicine and equipmentThe good or bad efficacy is also related to the spray tools used. Good quality spray tools not only save medicine and labor, but also improve the efficacy.

Function and usage of malathion

Malathion has good contact killing, stomach toxicity and certain fumigation effects, without internal absorption. After entering the insect body, it is oxidized to malathion, which can play a more toxic role. When entering warm-blooded animals, it is hydrolyzed by carboxylesterase, which is not found in the insect body, thus losing its toxicity. Malathion has low toxicity and short residual period of efficacy, and is effective against the pests of the biting mouthpiece and chewing mouthpiece.Role of malathion:1. Low-toxic, broad-spectrum insecticides and acaricides. It has the effects of touch killing and stomach poisoning, but also has weak fumigation, without internal absorption. Due to its strong killing power, rapid action and long-term use, many pests have developed resistance. It can be used to control pests of rice, wheat, cotton, vegetables, tea and fruit trees, such as aphids, rice planthoppers, rice leafhoppers, rice thrips, duckweed borers, crustaceans, red spiders, golden crustaceans, leaf miners, leaf hoppers, cotton leaf worms, slime worms, vegetable borers, tea leafhoppers and fruit tree heart-eaters. It can be used to kill mosquito and fly larvae and bedbugs, and can also be used to create pests in food.2. Malathion is a highly effective and low-toxic insecticide and acaricide with a wide range of control. It is not only used for rice, wheat and cotton, but also used for pest control of vegetables, fruit trees, tea and warehouses due to its low toxicity and short residual effect. It is mainly used to control rice planthopper, rice leafhopper, cotton aphid, cotton spider, wheat armyworm, pea weevil, soybean heartworm, fruit tree spider, aphid, mealy scale shell worm, nest moth, vegetable yellow jump, vegetable leaf worm, various scale insects on tea trees, as well as mosquitoes, fly larvae and bedbugs.3. It is a low-toxicity non-invasive insecticide and acaricide, widely used in agriculture and horticulture, and can also be used as household health medicine.Use method of malathion:1. Prevention and control of wheat crop pests, armyworm, aphid and wheat sawfly, spray with 45% emulsifiable concentrate 1000 times liquid.2. Prevention and control of bean crop pests. Soybean borer, soybean bridge worm, pea weevil, pea and pipe aphid, and yellow striped flea beetle shall be spray with 45% emulsifiable concentrate 1000 times, with a spray volume of 75-100 kg per mu.3. Prevention and control of rice pests: rice leafhopper and rice planthopper.4. Prevention and control of cotton pests. Cotton leaf jumpers and bug bugs should be spray with 45% emulsifiable concentrate 1500 times.5. Prevention and control of fruit tree pests All kinds of thorn moths, nest moths, mealy scale insects and aphids on fruit trees shall be spray with 45% emulsifiable concentrate 1500 times liquid.6. Prevention and control of tea plant pests Tea weevil, white scale, tortoise scale, tea cotton scale, etc., use 45% emulsifiable concentrate 500-800 times of liquid spray.7. Prevention and control of vegetable pests, such as cabbage caterpillar, vegetable aphid, yellow striped flea beetle, etc., use 45% emulsifiable concentrates and 1000 times liquid spray.8. Prevention and control of forest pests: geometrid, pine caterpillar, poplar moth, etc., use 150 to 200 ml of 25% oil per mu, and ultra-low volume spray.9. Prevention and control of health pests: use 45% emulsifiable concentrate 250 times of liquid at the rate of 100-200 ml/m2. The bedbug is treated with 160 times of 45% emulsifiable oil at the rate of 100-150 ml/m2. Cockroaches are treated with 45% emulsifiable concentrate 250 times as 50 ml/m2.

The foliar fertilizer spraying can be carried out at the same time

Chemical fertilizers and pesticides are indispensable means of production for modern agriculture. In order to improve the yield and quality, the number and types of chemical fertilizers applied by farmers are increasing day by day, among which foliar spraying fertilizer has become a technical measure often adopted by farmers, especially fruit farmers and vegetable farmers, due to its small amount of fertilizer and quick effect; On the other hand, farmers should also spray pesticides regularly to control diseases and pests. Many people try to mix medicine and fertilizer and spray them together with the purpose of saving labor and improving work efficiency. For example, the "one spray and three prevention" technology widely promoted in the northern wheat ear stage is to mix ketone (or diniconazole), piramifos (or acetamiprid) and potassium dihydrogen phosphate for a single spray. It can not only control wheat rust, powdery mildew and wheat aphid, but also reduce the damage of lodging and dry hot wind, achieving the good effect of saving labor, increasing production and income. The first reason why the "one spray and three prevention" technology is worthy of recognition and promotion is that the timing is appropriate. Because the spike stage of wheat is just the key period to control "two diseases and one insect" and to supplement the spike fertilizer and increase the 1000-grain weight, it needs to be mixed with medicine and fertilizer. In other periods, it may become a waste without targeted mixing. As far as the scientific use of pesticides is concerned, the preparation of liquid medicine with clear water can ensure the efficacy.The key of mixed use is that chemical reactions between fungicides and pesticides, and between drugs and fertilizers cannot occur, which does not affect the physical properties of drugs and fertilizers, such as solubility, suspension, emulsification, etc., nor affect their respective efficacy. Of course, if there is no chemical reaction, it will not increase the toxicity of drugs to humans, animals and plants and the decomposition of drugs and fertilizers. From the point of view of maintaining efficacy, we already know that some pesticides cannot be mixed with basic pesticides (sulfur mixture, Bordeaux liquid), such as fipronil, chlorfenuron, acetamiprid, tin and other insecticides and fungicides such as mancozeb, aluminum triethylphosphate, oxazolin, metalaxyl, ketone, diniconazole, isocarburide, chrysromycin, polyantimycin, and nanningmycin. It is reasoned that they cannot be mixed with basic or weakly basic fertilizers such as ammonium carbonate, plant ash, calcium magnesium phosphate, diammonium phosphate, borax and ammonium molybdate.Some plant growth regulators, such as gibberellin, chlormequat and ethephon, cannot be mixed with alkaline pesticides or fertilizers, otherwise they will decompose and fail. If herbicides are used for soil treatment, they are safe in most cases, especially when they are mixed with fine soil (or water) before use. However, if it is used for the treatment of stems and leaves, it should be very careful. When it is used alone, a slightly larger dose or uneven spraying may cause drug damage, so it should not be mixed with fertilizer generally. If mixed, the herbicide should also be prepared into the mother liquor first, and the fertilizer should also be dissolved with water before mixing with the mother liquor, and should be sprayed and prepared immediately.Biological pesticides cannot be mixed with chemical fertilizers or fungicides, because chemical fertilizers and fungicides may kill beneficial microorganisms and reduce the control effect. In addition, we should also pay attention to the special provisions of some chemicals on mixed use, such as a bactericide called chlorobromoisocyanuric acid, which can cure fungal, bacterial and viral diseases simultaneously, and is a rare good medicine. However, there are also provisions on "not to be mixed with other pesticides", which is not to be mixed with chemical fertilizers.

Study on the effects of plant growth regulators on the regulation of plant flowering

When the plant reaches a certain stage of growth and development, it will turn into reproductive growth under appropriate environmental conditions, that is, it will form flower buds at a certain position, and then blossom and bear fruit. The number of flower bud differentiation directly affects the later results and yield. Most fruit trees have the phenomenon of big and small years, which is caused by the number of flower bud differentiation. In order to reasonably control flower bud differentiation, people have done a lot of research:Pineapple is a fruit with very different maturity in the south, and the maturity period is only 20 days. The application of ethephon to promote flowering can make single crop fruit into multiple crop fruit. The planned use of ethephon at different times to promote its flower bud differentiation can extend the 25-30 day fruit harvest period of pineapple in South China to about 200 days, which is greatly beneficial to the production and market supply of pineapple.Some plant growth regulators, such as paclobutrazol, chlormequat, ethephon and cytokinin or their mixture, are widely used for apple size, which can completely control the high yield of the year and the high yield of the year, that is, reach the desired level.Other fruit trees, such as pears and grapes, can also use CCC and 6-BA to regulate their vegetative growth and promote flower bud formation.At the same time, the use of plant growth substances can also inhibit flower bud differentiation. Apple and pear can inhibit its excessive flower bud formation with about 300mg/L of gibberellin 2 to 6 weeks before flower bud differentiation in the year with many fruits; Gibberellin can also inhibit the flower bud differentiation of apricot, peach and cherry; Grape can also control its flower bud differentiation.In addition, the use of plant growth substances can also reduce the formation of ineffective flowers, delay the opening of flowers, and extend the flowering period. The formation of peanut ineffective flowers can be greatly reduced by regulating phosphorus; Applying gibberellin to grapes and some fruit trees with stone fruits in autumn can delay their flowering date in the next spring, which has certain production significance for preventing early frost in spring.Both paclobutrazol and CCC have the effect of prolonging the flowering time of chrysanthemum, especially paclobutrazol, which can prolong its flowering time by more than 10 days.

Correct use of paclobutrazol

Quanfeng paclobutrazol is a high-quality broad-spectrum plant growth regulator, which has the effects of significantly weakening the apical advantage of plants, regulating morphological differentiation, promoting lateral bud germination, promoting flower bud formation, improving flower setting rate, and enhancing stress resistance. It should master the following technical points when using:1、 Application method of paclobutrazolThe common methods of using paclobutrazol in flower production include soaking (seed ball), soil application, leaf spraying and drying. Among them, soaking, soil application and leaf spraying have good effects, and the efficacy is durable and stable. There are two methods of soil application. One is to plant leaf-viewing and flowering plants in the ground, dig a circular ditch with a depth of about 5 cm around the tree crown, evenly sprinkle it into the ditch, and then irrigate it in time; Second, for indoor potted flowers, water them in time after drilling holes in the potted soil. Leaf spraying is mostly conducted at the early stage of growth. The spraying time and concentration are different for different flowers, soil quality and nutrition management level. The spraying method is the same as the general fertilizer spraying method, but attention should be paid to the uniform spraying of the growth point.2、 Dosage and concentration of paclobutrazolIt varies due to variety, growth trend, age, soil quality and other factors. The amount of soil application is generally 0.25g per square meter, the concentration of the solution is 800-1500ppm when the leaves are sprayed, the concentration of the root (seed ball) is 70-90mg/L, and the solution is soaked for 5-8 hours. The application amount and concentration of woody flowers can be slightly higher than that of herbaceous flowers. Use orchids with caution.3、 Application timeDifferent application methods have different application time. The soil application of paclobutrazol is generally carried out before the spring flower buds sprout (spring flowers); Leaf spray is generally used when the new shoots grow about 10 to 15 cm in the current year. Deciduous flowers and trees can be used some time in advance to ensure timely effect.4、 Application timesBecause paclobutrazol has a lasting effect, the effect can last for 3 to 5 years if it is applied once, so the application times should be strictly controlled. Soil application shall be conducted at most once every three years, and leaf spray shall be conducted once a year. If it is used for consecutive years, the concentration shall be reduced year by year. If you find that the growth is extremely weak, you should stop using it. If necessary, you can spray gibberellin to help restore growth.5、 Stagnancy periodSince there is a period of time from the application of paclobutrazol to its efficacy - that is, the efficacy of paclobutrazol is sluggish, so it is very easy to mistake it as "ineffective" in production, and then repeat the application, resulting in excessive dosage. Before application; This factor should be fully considered to avoid losses.

Symptom analysis of 11 common plant growth regulators

Different plant growth regulators have different symptoms when they are harmed. Experts teach you to distinguish the symptoms of the following common plant growth regulators:1. Toxic symptoms of paclobutrazol: short plant, small root tubers, deformity, curly leaves, dumb flowers, early shedding of old leaves at the base, twisting and shrinking of young leaves. For cotton, the plant is seriously stunted, the fruit branches cannot extend, the leaves are deformed, the buds are clumped, and the buds fall. Peanut leaves are small, the plant does not grow, the peanut fruit is small, and premature aging occurs. As the efficacy of paclobutrazol lasts a long time, it will also cause drug damage to the next crop, resulting in no emergence, late emergence, low emergence rate, seedling deformity and other drug damage symptoms.2. Symptoms of chloramphenicol poisoning: the leaves become smaller and thicker, the internodes are dense, the vegetative buds are clustered, and the plant growth is uneven, resulting in a large number of buds and bolls falling off, resulting in late green and late maturity of cotton. There are few key points in the use of acetaminophen on gramineous plants, and the dosage range is wide. Generally, the damage caused by chlorphenamine will not cause damage to the next crop.3. Symptoms of compound nitrophenol sodium poisoning: the symptoms of mild poisoning are inhibition of plant growth and poor development of young fruit; The severe drug damage is plant wilting, yellowing and death. The damage caused by sodium nitrophenolate is less frequent, mainly on sensitive crops such as peach trees and watermelon, resulting in crop flower drop, fruit drop, hollow fruit and other phenomena.4. Symptoms of ethephon: the top of the plant wilts, the leaves, flowers and young fruits at the lower part of the plant gradually turn yellow and fall off, and the residual fruits mature in advance. The serious drug damage is that the whole plant leaves turn yellow and fall off rapidly, and the fruit ripens and falls off rapidly, leading to the death of the whole plant. According to China Pesticide Network, excessive use of ethylene or improper use of time can cause drug damage. The damage of ethephon will not affect the next crop.5. Symptoms of a-naphthylacetic acid toxicity: the mild naphthylacetic acid toxicity is characterized by defoliation of flowers and young fruits, which has little impact on plant growth. The more serious drug damage is leaf atrophy, petiole overturning, leaf falling off, and fruit rapidly maturing and falling off. As for the damage caused by soaking seeds, the light will lead to fewer roots and deformed roots, and the heavy will lead to no rooting and seedling emergence. A-Naphthylacetic acid will cause harm to the next crop, but most of them will not cause harm to the next crop.6. Symptoms of DA-6 (amine fresh fat) drug damage: the leaves have spots, and then gradually expand, with light yellow gradually turning to dark brown, and then transparent. DA-6 (amine fresh fat) has only been damaged on peach trees, and no drug damage has occurred on other crops so far.7. Symptoms of triacontanol poisoning: when triacontanol is used in a large amount or with a low purity, it will cause the sheath to bend at the seedling stage, the root to be deformed, and the adult plant will cause the young leaves to curl.8. Symptoms of brassinolide poisoning: plants grow wildly, fruits are few and small, and rigid fruits are formed in the later stage.9. Symptoms of gibberellin poisoning: the fruit is stiff and cracked, the fruit tastes astringent, and the plant is green and late maturing.10. Symptoms of chlormequat poisoning: the plant is seriously stunted, the fruit branches can not extend, the leaves are deformed, there are chicken feet leaves, vegetative buds are clustered, the fruit branch nodes are too short, the plant branches and leaves are brittle and easy to break. The roots are bent and the young leaves are seriously not long after soaking, and the emergence is delayed for 7 days, and the seedlings are distorted after emergence. The chlormequat is easy to produce critical effects on dicotyledonous plants, but not on monocotyledonous plants. Generally, chlormequat does not affect the next crop.11. 2. Symptoms of 4-D drug damage: symptoms of mild drug damage include softening and bending of petiole, drooping of leaves, curling of top heart leaves, leaf deformity, fruit deformity, hollow fruit formation and fruit cracking. The severe drug damage is that most of the leaves of the plant droop, the heart leaves curl seriously, deformity and contraction occur, the growth points of the plant shrink and necrosis, and the whole plant withers and dies gradually. Therefore, the improper use of 2 and 4D will kill plants like herbicides. The main key is that the damage to dicotyledonous plants is heavier and the damage to monocotyledonous plants is lighter.The above are the symptoms of common plant growth regulators causing drug damage. Find and remedy the drug damage in time to avoid causing economic losses. (China Pesticide Network)