【1】Commodity name Paclobutrazol, PP333, Chlorbutamol

【2】 Chemical name (2RS, 3RS)-1-(4-chlorophenyl)-4,4-Dimethyl

-2-(1H-1,2,4-triazol-1-yl)pentane-3 -alcohol

【3】CAS No. 76738-62-0

【4】Molecular formula C15 H2o ClN3

【5】Relative molecular mass 293.79

【6】Physical and chemical properties

The appearance of the original drug is white crystal, the melting point is 165～166℃, insoluble in water, soluble in methanol, ethanol, acetone, dichloromethane and other organic solvents, stable to acid and alkali, and stable in storage at room temperature.

[9] Toxicity Low toxicity

【7】Main dosage forms 95% paclobutrazol original drug, 15% paclobutrazol wettable powder, 25% paclobutrazol suspension

【8】Features

Paclobutrazol is a triazole plant growth retarder. Paclobutrazol is an inhibitor of endogenous gibberellic acid synthesis, which can increase the content of chlorophyll, protein and nucleic acid in plants, reduce the content of gibberellic acid and indole acetic acid, delay plant growth, inhibit stem elongation, shorten node spacing, It can promote plant tillering, enhance plant stress resistance, increase yield, improve quality and improve economic benefits.

【9】Applied technology

1.Cultivate strong seedlings to improve stress resistance

Rice

Soaking seeds with 100mg/L paclobutrazol solution for 24 hours or spraying with 200-300mg/L solution at 1 leaf and 1 heart stage can effectively inhibit the elongation and growth of seedlings, significantly reduce plant height, increase stem thickness, and promote the growth of lateral roots. Increase root thickness and root volume. It can make the seedlings strong, the leaves are dark green, the root system is developed, and the lodging in the later stage can be prevented.

Wheat

Soaking seeds with 100mg/L paclobutrazol solution for 24 hours or spraying the whole plant with 200-400mg/L solution at 1 leaf and 1 heart stage can control plant height, increase chlorophyll content, promote greening, and enhance plasma membrane stability. Enhance seedling resistance.

Corn

Soaking the seeds with 100-200mg/L liquid medicine for 10-12 hours before sowing, stirring once every 3-4 hours, and sowing after drying can promote the growth of the seedlings and enhance the resistance of corn.

Rapeseed

Spraying the seedbed with 100-150mg/L paclobutrazol liquid at the 3-4 leaf stage can promote strong seedlings, promote root development, and improve the survival rate after transplanting.

Watermelon

Spraying 5 mg/L paclobutrazol solution on the substrate at the seed germination stage or spraying 10 mg/L paclobutrazol solution at the cotyledon micro-expansion stage can significantly reduce the plant height of watermelon seedlings, increase the stem thickness, and the relative chlorophyll content of leaves ( SPAD value), root vigor, root-shoot ratio and strong seedling index were significantly improved.

Melon

Sowing seeds with 100-150mg/L paclobutrazol solution for 4 hours can promote the dwarfing of plants and make the seedlings robust, but high concentration of paclobutrazol will inhibit the germination of seeds; 28d after sowing, use 100-200mg/ paclobutrazol solution leaves Spraying the seedlings on the surface can prevent the leggy growth of the melon plug seedlings, which is conducive to the cultivation of strong seedlings.

Zucchini

After 3-4 true leaves are unfolded, foliar spraying with 5-20mg/L liquid medicine can shorten the internodes, thicken the leaves, and increase the cold resistance and disease resistance.

Tomato

Coating tomato seeds with 150mg/L paclobutrazol or spraying mg/L paclobutrazol at the 3-leaf stage of tomato can effectively reduce seedling height, increase stem diameter, dry (fresh) weight per plant and free proline content in leaves, and improve root vigor and seedling index.

Chili

When the seedlings are 6~7ccm, spraying with 10~220mg/L liquid on the leaves can promote strong seedlings and root development.

When eggplant has 5 to 6 true leaves, foliar spraying with 10-20mg/L liquid can make eggplant seedlings robust and improve stress resistance.

Cucumber

Foliar spraying with 30-40 mg/L paclobutrazol liquid during the cotyledon flattening period can effectively inhibit the occurrence of leggy phenomenon in cucumber seedlings. were significantly improved. Among them, the plant height of cucumber self-rooted seedlings decreased by 24.7%, and the plant height of rootstock seedlings decreased by 45.8%. The chlorophyll content of seedling leaves increased by 38.2%, the fresh weight and dry weight increased by 37.9% and 23.1%, respectively, and the seedling strength index increased by 82.8%.

Pumpkin

Soaking seeds with 20～30mg/L paclobutrazol liquid for 6h can effectively inhibit the growth of hypocotyl, increase stem thickness, and decrease cotyledon thickness. At the same time, it has no obvious influence on the seedling emergence rate of pumpkin rootstock seeds, and the seedling emergence rate is all over 80%, which is conducive to cultivating strong seedlings and facilitates agricultural operations.

Strawberry

After the female parent seedlings were colonized and survived, 25-30mg/L of the medicinal solution was sprayed twice on the foliage with an interval of 10 days; at the same time, 2 months after the colonization, 70-150 mg/L of the medicinal solution was sprayed once, which can make the plants Short and strong, the stolons are shortened and thickened, the number of shoots is increased, the rhizomes of the seedlings are thickened and the number is increased, and it can prevent anthracnose in the later stage, meeting the requirements of disease-free and healthy seedlings.

Sugar cane

Soaking seeds with 50mg/L paclobutrazol solution for 24h can effectively improve and advance the occurrence of tillering of sugarcane seedlings.

Red okra

Soaking seeds with 4 mg/L paclobutrazol solution for 16 hours can dwarf the height of red okra seedlings, increase the stem thickness of the seedlings, optimize the plant shape of the seedlings, increase the content of chlorophyll a, chlorophyll b and the total amount of chlorophyll in the leaves, and improve the SOD of the seedlings And POD activity, improve seedling quality.

Cassia

Soaking seeds with 100 mg/L paclobutrazol solution for 24 hours could significantly increase the content of chlorophyll and soluble sugar in Cassia seedlings, which was beneficial to the accumulation of photosynthetic products and enhanced the root vigor of seedlings. Concentrations over 1000 mgg/L have inhibitory effects.

Salvia splendens

In the 2-leaf 1-heart stage, spraying with 30 mg/kg paclobutrazol for 1 or 2 times can shorten the internodes, thicken the leaves, and harden the texture, 7-10 days before flowering.

Snapdragon

In the 2-leaf 1-heart stage, spraying with 2 mg L of paclobutrazol can effectively control the leggy growth of snapdragon plug seedlings and improve the quality of plug seedlings.

Stevia

In the peak branching stage, spraying with 300 mg/L paclobutrazol liquid can increase the content of amino acids, chlorophyll, glycosides and flavonoids in Stevia, and effectively improve the quality and resistance.

Sand shrubs such as poplar wood, sand cypress and other sandy shrubs can be irrigated at a concentration of 0.5gg/m2 or 300mg/L, which can inhibit the vertical growth of shrubs, reduce leaf area and aboveground biomass, increase drought resistance, and promote root growth. Improve the survival rate, improve the vegetation coverage, and achieve the purpose of windbreak and sand fixation.

Amorpha

Spraying 100-200mg/L paclobutrazol before drought can improve the soluble protein, chlorophyll, soluble sugar content and water retention capacity of leaves, and significantly improve the drought resistance of plants.

2.Inhibit vegetative growth and increase yield

Rice

For high-yield fields with locally prosperous and long, tall stalks prone to lodging, 7-10 days before jointing, spraying the whole plant with 200-250 mg/L of medicinal solution can promote tillering, dwarf plants, control growth, and enhance lodging resistance.

Wheat

Before the wheat gets up to jointing, it is sprayed on the whole plant after diluting the active ingredient g per mu, which can control the plant height, promote the greening, promote the fullness of the grain, and increase the yield.

Peanut

Spraying the whole plant with 150-300mg/L paclobutrazol liquid at the full blooming stage can promote needles, increase the number of results, and increase yield.

Cotton

Spraying the whole plant with 150mg/L paclobutrazol liquid at the bud stage can dwarf the plant, promote the boll to sit on the peach, and increase the yield.

Soybean

Spraying the whole plant with 100-200mg/L paclobutrazol liquid in the early flowering period can prevent the plant from growing too long, reduce the plant height, improve the field density, increase the stem diameter, and significantly increase the protein content of the seeds.

Adzuki beans

Spraying with 200mg/L paclobutrazol at the branching stage, early flowering stage and full flowering stage could inhibit the growth of plant height, increase the content of chlorophyll, reduce the content of malondialdehyde, and improve the resistance. However, the quality indicators of treatment at different periods have different changes: treatment at the branching stage can significantly promote the thickening of the stem and the number of branches; treatment at the early flowering stage can maximize the dry matter weight and significantly increase the soluble sugar and the number of branches. The content of soluble protein has a significant effect of increasing yield; treatment at full bloom stage has no significant effect on the number of main stem nodes and stem diameter. In general, the treatment at the early flowering stage is better than the use at the branching stage and the full flowering stage.

Potato

When the plant height is 25-30cm, spray the whole plant with 250-300mg/L paclobutrazol liquid, which can inhibit the leggy growth of stems and vines, promote the transfer of nutrients to the rhizome, promote the expansion of the rhizome and increase the yield.

Watermelon

When the vines grow to about 60cm, spray 100-L paclobutrazol liquid on the overgrown plants, which can control the leggy growth of the vines.

Sweet potato

Spraying 150-300mg/L paclobutrazol liquid on the leaves at the branching stage can properly inhibit the growth of potato vines, promote the formation of tubers, and have a significant effect of increasing yield.

Betel nut

When the seedling height is about 1m and 5-6 leaves have grown, spraying with 7.5-12g of active ingredients per acre with water has the effect of dwarfing the plant and promoting the expansion of the female taro, and the residual amount of paclobutrazol is lower than the limit standard.

Radish

The use of paclobutrazol at 100-150mg/L in the early stage of the formation of radish fleshy roots can effectively prevent the plants from becoming leggy, deepen the leaf color of the plants, make the leaves short and erect, promote photosynthesis, and promote the transport of photosynthetic products to the fleshy roots, which has a significant effect of increasing production.

Ginseng

At the end of the emergence stage, spray the whole plant with 200-336mg/L paclobutrazol liquid or spread with 0.03-0.05g of active ingredients per square meter mixed with soil, which can control the nutrient consumption of ginseng, accelerate reproductive growth, increase chlorophyll content, and reduce diseases. Increase yield and quality rate.

Water bamboo

300mg L paclobutrazol can shorten the length of the internodes, significantly reduce the plant height, promote effective tillering, and increase the yield of the water.

Ophiopogon

Use 1000mg/L paclobutrazol or 1.5g/㎡ for the first treatment in early September, and the second treatment in early October or early November, which can reduce the number of vegetative roots in the underground and increase the number of tuberous roots. The fresh weight and dry weight increase the root-shoot ratio, and the proportion of larger and larger tuberous roots increases, and the yield increase effect is obvious.

Aconitum

When the plant grows to 40cm, 150mg/L paclobutrazol liquid is sprayed twice on the foliage with an interval of 20d, which can dwarf the plant, increase the stem thickness, prevent lodging, and improve yield and traits.

3.Control the growth of new shoots and promote flower bud differentiation

Apple

The application of paclobutrazol on apple trees can inhibit the growth of vegetative bodies and increase the content of chlorophyll; inhibit the growth of terminal buds, promote the germination of lateral buds and the formation of flower buds, increase the number of flower buds, improve fruit set rate, improve fruit quality, increase yield, and improve cold resistance ability etc. In actual production, there are methods such as furrow application, leaf spraying and coating drying. ①Ditch application, after apple picking or before budding, open a circular shallow ditch in the soil under the canopy, add 2-4g of active ingredients to each plant and apply 50-90mg L of liquid medicine into the ditch evenly, and cover the soil after the liquid seeps in. . ②Foliar spray, when the new shoots grow to 5-10cm, spray the leaves with 750-1000mg/L liquid medicine. ③Apply dry, 20-30d after flowering, apply 1000mg/L liquid medicine to the trunk. (Note: Different apple varieties have different sensitivities to paclobutrazol, and the dosage should be determined on the basis of local experiments. The use of paclobutrazol for many years in apples should be determined according to the growth of the tree to prevent excessive drug use and affect apple yield.)

Pear

When the new shoots grow to 5-10cm, spray with 500-1000mg/L paclobutrazol liquid on the leaves, which can control the growth of new shoots, promote the differentiation of flower buds, and improve the fruit setting rate.

Bayberry

Generally, soil application and foliar spraying can be used. Soil application can be from October to March of the following year, with November being the best, with 0.1 to 0.5g of active ingredients per plant, diluted with soil or fine sand, evenly sprinkled under the crown of the tree, and then covered with soil, which can effectively inhibit the spring shoots of the following year. and root growth, the application rate depends on tree vigor and variety. The varieties with weak tree vigor (water plum) are applied with 0.1g per square meter of active ingredients, the varieties with medium tree vigor (“water chestnuts” bayberry, “deep red” bayberry) use 0.15-0.25g, and the varieties with strong tree vigor ( “Donghuai” bayberry) with 0.4 ~ 0.5g. When foliar spraying is used, 1000mg/L of liquid medicine is sprayed on the unfruitful vigorous trees in the spring or summer shoots to less than 5cm or before the flower buds differentiate, which can effectively inhibit the growth of new shoots and reduce nutrient consumption. Promote flower bud differentiation, improve fruit set rate and stress resistance.

Peach, Hawthorn

In autumn or spring, with 15% paclobutrazol wettable powder 10-15g per plant; or spraying 500-1000mg/L liquid, which can effectively inhibit the growth of new shoots, reduce nutrient consumption, promote flower bud differentiation, and improve fruit setting rate and resilience. (Note: Nectarine is more sensitive to paclobutrazol, and more than 300mg/L is likely to cause strong inhibition on the fruit weight of the current year and the tree growth of the next year.)

Apricot, Plum

For large and young trees that do not bear fruit at the right age, when the new shoots grow to less than 10cm, spray 250-3000-300mg/L paclobutrazol liquid, which has obvious effect of controlling shoots and promoting flowers.

Tangerine

Before summer shoots start to grow or when new shoots grow to within 3cm, 250-1000mg/L paclobutrazol liquid is sprayed on the foliage for ~2 times, which can shorten summer shoots by 50%-70% and increase fruit setting rate by 2%-4%. %, the output is increased by 6 to 48%. In production and application, the concentration and frequency of use of different varieties are different: the best concentration of sago tangerine is 300mg/L, the best concentration of Wenzhou mandarin is 750mg/L, the best concentration of ponkan is 1000mg/L, and the best concentration of “local early” It is 500mg/L, and the use range of orange is 250-750mg/L.

Litchi

300-400 mg/L paclobutrazol was sprayed in the early stage of flower bud differentiation (white spots of terminal buds) when the autumn shoots of “Feizixiao” lychees were mature and the winter shoots were not smoked. The effect of 15d after spraying was combined with ring cutting of the main stem to control shoots and promote flowering. , can make it bloom earlier; and spraying with 200mg/L paclobutrazol liquid 50d after the full bloom period can promote the formation of anthocyanins and promote the coloring of the peel.

Longan

After the autumn shoots are mature, spray 200-400mg/L paclobutrazol on the foliage once, and then spray once after 20 days, which can inhibit the growth of shoots and increase the nutrient accumulation of the tree, and is suitable for vegetative growth. Overgrown juvenile and adult trees.

Cherry

Soil application of paclobutrazol 0.5-1g per square meter of canopy projection area or spraying 1000mg/L paclobutrazol liquid in the long-term growth of new shoots (new shoot length less than 7.5cm) can control the growth of shoots, promote nutrient accumulation, and increase fruit set rate.

Loquat

During the summer shoot growth period, 500-700mg/L paclobutrazol solution was sprayed on the foliage, which can significantly inhibit the growth of summer shoots, which is beneficial to nutrient accumulation, and is beneficial to flower bud differentiation, delaying flowering period and reducing freezing damage.

Grape

For soil application, 0.5-1g per square meter is appropriate, or when the new shoots grow to 3-10cm after flowering, spray 1000-2000mg/L of liquid medicine on the leaves, focusing on the new shoots, which can inhibit the growth of the main shoots and auxiliary shoots. Leggy, increase yield.

Mango

The combination of soil application and foliar spray is commonly used in mango control and foliar spraying: ① soil application, after the mature leaves of mango two stalks turn green, each plant is subjected to the size of its crown (1.5-3.0m crown), soil application The active ingredient of paclobutrazol is 1.5-4.5g. After mixing with appropriate amount of water, pour it on the drip line to cover soil and compact; in the later stage of autumn shoot growth, add 15-20g of 15% paclobutrazol wettable powder to each plant and add 15-20kg of water to the mango tree crown. A ring trench with a depth and width of about 15cm is excavated in the drip line, and paclobutrazol is mixed with water and then sprayed into the ring trench, and then covered with soil. ② Controlling the shoots on the foliage. After the shoots are mature, spray 625mg/L paclobutrazol liquid on the foliage, spray once every 7 days, and spray 4 times in a row, which can obviously prevent the shoots, effectively control the tree vigor, and promote the aging of the leaves. Ripe to promote flowering.

Jujube

When the jujube before flowering reaches 8 to 9 leaves, 1000mg/L for young trees and 2000mg/L for mature trees can be sprayed on the whole tree, which can inhibit the vigorous growth of new shoots, improve fruit setting rate and increase yield.

Kuding tea

Before the shoots of Kudingcha grow rapidly, spray the whole plant with 300mg/L paclobutrazol liquid, which can make the plant dwarfed, reduce the apical dominance of the seedling plant, and avoid the difficulty of picking tea.

Chestnut

Before germination in spring, soil application of 0.15-0.5g paclobutrazol per square meter of canopy projection area or spraying the crown with 1000-1500mg/L liquid medicine for a long time in the new shoots can play a role in controlling shoots and promoting flowering.

Walnut

At the end of April or the beginning of May, soil application of 0.3-0.6g paclobutrazol per square meter of canopy projection area or spraying 1000-2000mg/L paclobutrazol liquid on the leaves when the spring shoots grow to about 15cm can effectively inhibit the elongation and growth of walnut fruiting branches. Increase the number of short branches, reduce the crown, increase the number of male and female flowers, and increase the yield.

4.Adjust plant shape, chemical shaping

Money tree

Spraying leaves or irrigating roots with 300-1200 mg/L paclobutrazol during the growth period can make the leaf axis dwarf, the leaflet spacing shortened, the petiole base thicker, and the compound leaf relative growth rate decreased. Among them, the effect of root irrigation was better than that of spraying leaves, and its concentration was closely related to tree age and spraying method. It is recommended to use 300mg/L paclobutrazol for leaf spraying for 1-year-old money tree, 300mg/L paclobutrazol for root irrigation or 600mg/L paclobutrazol for 2-year-old money tree.

Three-year-old money tree was sprayed with 1200mg/L paclobutrazol.

Dahlia

When the plant height is 20cm, 50-75mg/L paclobutrazol liquid is irrigated once, which can make the plants dwarf, shorten the internodes and petioles, thicken the stems, increase the flower diameter, the number of petals and the area of ​​the petals, and prolong the flowering period. Improve viewing.

Cloves

After 7 days of cutting and planting, the soil was irrigated with 20mg/L liquid medicine, and the second time after 30 days, it can promote the growth of side branches and has a beautiful appearance.

Osmanthus fragrans

Spraying the foliar surface once a year before the shoots in the spring with a concentration of 800mg/L can make the new leaves smaller and thicker, the internodes are shortened, the plants appear compact and attractive, and the ornamental value is greatly improved.

Rose

After pruning, when the new branches grow to 5-10 cm, the soil is irrigated with a concentration of 300 mg/L to prevent the branches from growing too long.

Marine microalgae

Paclobutrazol has a significant inhibitory effect on the growth of different species of marine microalgae, but its activities are also different. Among them, paclobutrazol has a 96h half-inhibitory concentration value on P. (96h-EC50) were 28.60, 24.94, 24.97 and 5.62 mg/L, respectively.

Boxwood

In the rapid growth period of autumn shoots, spraying or root irrigation with 300mg/L paclobutrazol liquid can significantly inhibit the growth of autumn shoots, increase chlorophyll content, significantly increase root weight and reduce overwintering sprouts, and the root irrigation effect is better than spraying. Apply treatment.

Hedge

Spraying with 400-800mg/L paclobutrazol 1 day after pruning at the seedling stage and the adult stage can effectively control the growth of new shoots, reduce the number of prunings and reduce maintenance costs on the basis of ensuring the ornamental effect. Among them, Fujian tea varieties are more effective than hibiscus.

Zoysia sylvatica

In the growing season, 250-350 mg L of paclobutrazol was sprayed 4 times with an interval of 14 days, which could increase the chlorophyll content of the leaves, promote the greenness of the leaves, and increase the ornamental quality.

Tall fescue, Ryegrass, Manila grass

During the peak growth period, soil application of 0.4g of paclobutrazol per square meter or foliar spray of paclobutrazol liquid of 600-800mg/L can delay the growth rate of the lawn, and increase the chlorophyll content significantly, shorten the internodes, and reduce pruning. times, reducing maintenance costs.

5.Delay aging, promote freshness, and improve storability

Rrose

Using 150mg/L paclobutrazol liquid, combined with sucrose, 8-hydroxyquinoline citrate, etc. as a bottle insert treatment, can effectively increase the fresh weight of cut flowers, increase flower stems, improve the moisture status of cut flowers, reduce proline and Malondialdehyde content can delay the increase of membrane permeability, thereby delaying the senescence of cut flowers and increasing the lifespan of cut flowers.

Peony

Using 200mg/L paclobutrazol liquid for infusion treatment of peony cut flower vase can make the fresh weight of cut flower branches long, the flower diameter is large, the degradation rate of soluble protein is slow, and the relative conductivity is small, which can delay the arrival of the respiration peak of cut peony, improve the The water balance in the body of cut flowers can enhance the antioxidant capacity of cut flowers and achieve a certain fresh-keeping effect.

Gerbera

Using 10mg/L paclobutrazol liquid, combined with sucrose, 8-hydroxyquinoline citrate, etc. as a bottle insert treatment, can increase the fresh weight of cut flowers, increase the flower diameter, improve the water balance in the body, reduce the accumulation of free proline, maintain The relative stability of the cell membrane structure can delay the senescence of cut flowers.

Spring flowers

Using 5mg/L paclobutrazol liquid for bottle insertion treatment can improve the water balance in the body of cut flowers, enhance the antioxidant capacity of cut flowers, and achieve a certain fresh-keeping effect.

Tulip

Using 1mg/L paclobutrazol liquid with 2% sucrose as a bottle infusion treatment can increase the catalase activity of cut flower petals and top leaves of flower branches, reduce cell membrane permeability, delay flower senescence, and prolong fresh-keeping period for 4-5 days. .

【13】Notes

① The residual period of paclobutrazol is long. After the field is harvested, the land should be deeply ploughed to avoid inhibiting the next crop.

②Try not to contact with skin and eyes, if splashed into eyes, rinse immediately with plenty of water, and wash skin with soap. If swallowed by mistake, induce vomiting and seek medical attention in time.