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The difference of Paclobutrazol, Uniconazole, Chlormequat Chloride, and Mepiquat chloride

Date: 2024-03-21 15:40:54
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Crop vigorous growth has a great impact on crop growth . Long-growing crops have fresh stems and leaves, thin and large leaves, pale leaves, and dense plants, resulting in poor ventilation and light transmission, excessive humidity, reduce disease resistance, and prone to disease;due to excess vegetative growth, too much nutrients are concentrate to supply the growth of stems and leaves, resulting in less flowering and fruit drop.

At the same time, due to the vigorous growth, crops are greedy and late-maturing.  What's more serious is that the plants of vigorous crops have long internodes, thin stems, poor toughness and elasticity.They will fall down when encountering strong winds, which not only directly reduces yields, but also makes harvesting more difficult and increases production costs.

The four plant growth regulators, Paclobutrazol, Uniconazole, Chlormequat Chloride, and Mepiquat chloride, all control plant growth in a short period of time by inhibiting the synthesis of Gibberellic acid in plants. It inhibits the vegetative growth of plants to promote reproductive growth, prevents plants from growing vigorously and leggy, dwarfs plants, shortens internodes, improves stress resistance, etc., makes crops have more flowers, tillers, and fruits, increases chlorophyll content, and improves stress resistance.Improve photosynthesis, thereby controlling growth and increasing yield.

Paclobutrazol can be widely use in most of field crops and commercial crops , such as rice, wheat, corn, rape, soybean, cotton, peanut, potato, apple, citrus, cherry, mango, lychee, peach, pear, tobacco, etc.  Among them, field crops and commercial crops are mostly use for spraying in the seedling stage and before &after the flowering stage. Fruit trees are mostly used to control the crown shape and inhibit new growth. It can be spray, flush or irrigate.
It has an extremely significant effect on rapeseed and rice seedlings.

wide application range, good overgrowth control effect, long efficacy, and good biological activity.  However, it is easy to cause soil residues, which will affect the growth of the next crop, and is not suitable for long-term continuous use.  For plots where Paclobutrazol is used, it is best to till the soil before planting the next crop.

Uniconazole is generally the same as paclobutrazole in usage and uses.Compared with Paclobutrazol, Uniconazole has a stronger control and sterilization effect on crops and is safer to use.

Strong efficacy, low residue, and high safety factor.   At the same time, because Uniconazole is very powerful, it is not suitable for use in the seedling stage of most vegetables (Mepiquat chloride can be use), and it can easily affect the growth of seedlings.

Chlormequat Chloride is a quaternary ammonium salt plant growth regulator. It is commonly used in the seedling stage like Paclobutrazol. The difference is that Chlormequat Chloride is mostly use in the flowering and fruiting stages, and is often used on crops with a short growth period.

Chlormequat Chloride is a low-toxicity plant growth regulator that can enter plants through leaves, twigs, buds, roots, and seeds, inhibiting the biosynthesis of Gibberellic acid in plants.  

 Its main physiological function is to control plant growth, promote reproductive growth, shorten the internodes of the plant, make the plant short, strong, thick, with a well-developed root system, resist lodging, have dark green leaves, increase chlorophyll content, enhance photosynthesis, increase fruit setting rate, and can improve the quality and yield; at the same time, it can also improve the cold resistance, drought resistance, salt-alkali resistance, disease and insect resistance and other stress resistance of some crops.

Compared with Paclobutrazol and Uniconazole, Mepiquat chloride has relatively mild medicinal properties, a high safety factor, and a wide range of uses. It can be use in all stages of crops and basically no adverse side effects. However, its efficacy is relatively short and weak, and its effect in controlling excessive growth is relatively poor. Especially for those crops that are growing too vigorously, they need to be use multiple times to control the growth.

Mepiquat chloride is a new type of plant growth regulator. Compared with Paclobutrazol and Uniconazole, it is milder, non-irritating and has higher safety.

Mepiquat chloride can be applied at basically all stages of crops, even in the seedling and flowering stages when crops are very sensitive to drugs. Mepiquat chloride has basically no adverse side effects and is not prone to phytotoxicity. It can be said to be the safest on the market.   

Mepiquat chloride has a high safety factor and a wide shelf life. However, although it has a growth control effect, its efficacy is short and weak, and its control effect is relatively poor.   Especially for those crops that grow too vigorously, it is often needed.  Use multiple times to achieve the desired results.

Paclobutrazol is often used in the seedling and shoot stages, and is good for peanuts, but has a mediocre effect on autumn and winter crops; Chlormequat Chloride is mostly used during the flowering and fruiting stages, and is often used on crops with a short growth period, Mepiquat chloride is relatively mild, and after damage, Brassinolide can be spraying or watering to increase fertility to alleviate the problem.
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