Plant growth retarder is a must in the process of crop planting. By regulating the vegetative growth and reproductive growth of crops, better quality and higher yield can be obtained. Plant growth retardants usually include paclobutrazol, uniconazole, peptidomimetics, chlormethalin, etc. As a new type of plant growth retardant, prohexadione calcium has received widespread attention in the market in recent years, and the number of registrations has also increased rapidly. Then, paclobutrazol, niconazole, paroxamine, chlorhexidine, and prohexadione calcium, what are the differences in the market applications of these products?
(1) Prohexadione calcium: It is a new type of plant growth retarder.
The function is that it can inhibit GA1 in gibberellin, shorten the stem elongation of plants, and thus control the leggy growth of plants. At the same time, it has no effect on GA4 which controls plant flower bud differentiation and grain development.
Prohexadione calcium was launched in Japan in 1994 as an acyl cyclohexanedione growth retardant. The discovery of prohexadione calcium is different from that of quaternary ammonium salts (chameleon, mepinium), triazoles (paclobutrazol, alkene) Plant growth retardants such as oxazole) have created a new field of late-stage inhibition of gibberellin biosynthesis, and have been commercialized and widely used in Europe and the United States. At present, prohexadione-calcium is widely concerned by domestic enterprises, the main reason is that compared with triazole retarders, prohexadione-calcium has no residual toxicity to rotating plants, no pollution to the environment, and has a strong advantage. In the future, it may replace triazole growth retardants, and has broad application prospects in fields, fruit trees, flowers, Chinese medicinal materials and economic crops.
(2) Paclobutrazol: It is an inhibitor of plant endogenous gibberellic acid. It has the effects of delaying plant growth, inhibiting crop stalk elongation, shortening internodes, promoting tillering, increasing plant stress resistance, promoting flower bud differentiation and increasing yield. Paclobutrazol is suitable for crops such as rice, wheat, peanuts, fruit trees, soybeans, lawns, etc., and has a remarkable effect of controlling growth.
Side effects of paclobutrazol: Excessive use can cause dwarf plants, deformed roots and tubers, curled leaves, dumb flowers, premature shedding of old leaves at the base, and twisted and shrinking young leaves. Due to the long duration of paclobutrazol efficacy, excessive use will remain in the soil, and it will also cause phytotoxicity to the next crop, resulting in no seedling, late emergence, low seedling emergence rate, and seedling deformity and other phytotoxic symptoms.
(3) Uniconazole: It is also an inhibitor of gibberellin. It has the functions of regulating vegetative growth, shortening internodes, dwarfing plants, promoting lateral bud growth and flower bud differentiation, and enhancing stress resistance. Due to the carbon double bond of paclobutrazol, its biological activity and medicinal effect are 6 to 10 times and 4 to 10 times higher than that of paclobutrazol, respectively, and the residual amount in soil is only about a quarter of that of paclobutrazol, and its efficacy The decay rate is faster, and the impact on subsequent crops is only 1/5 of that of paclobutrazol.
Side effects of uniconazole: when used in excessive doses, it will cause phytotoxicity, causing plant burns, withering, poor growth, leaf deformity, falling leaves, falling flowers, falling fruits, late maturity, etc., and application in the vegetable seedling stage will also affect the growth of seedlings , It is also toxic to fish and is not suitable for use in fish ponds and other aquatic animal farms.
(4) Peptidamine (Mepinium): It is an inhibitor of gibberellin. It can enhance the synthesis of chlorophyll, the plant is robust, can be absorbed through the leaves and roots of the plant, and transmitted to the whole plant, thereby inhibiting cell elongation and apical dominance, and can also shorten the internodes and make the plant type compact. It can delay the vegetative growth of the plant, prevent the plant from flourishing, and delay the sealing. Peptamine can improve the stability of cell membranes and increase plant stress resistance. Compared with paclobutrazol and uniconazole, it has milder medicinal properties, no irritation, and higher safety. It can basically be applied in all periods of crops, even in the seedling and flowering stages when crops are very sensitive to drugs. , and basically no adverse side effects.
(5) Chlormetrodin: It achieves the effect of controlling hyperactivity by inhibiting the synthesis of endogenous gibberellin. Chlormetrodin has a regulating effect on plant growth, balances vegetative growth and reproductive growth, improves pollination and fruit setting rate, and increases effective tillering. Delay cell elongation, dwarf plants, sturdy stems, and shorten internodes.
Different from paclobutrazol and mepiperonium, paclobutrazol is often used in the seedling stage and new shoot stage, and has a good effect on peanuts, but the effect on autumn and winter crops is general; On short crops, the improper use of chlormethalin will often cause crop shrinkage and the phytotoxicity is difficult to relieve; mepiperinium is relatively mild, and can be relieved by spraying gibberellin or watering to increase fertility after phytotoxicity.
Post time: Jul-19-2022