Six application methods of plant growth regulator on plant growth
a. Promote cutting rooting. Plant growth regulator can promote the cutting rooting of woody plant. Especially for some flowers, fruit trees and reproducing tree species that are difficult to take root, after being treated with plant growth regulator, cuttings will take root fast as well as it will have strong drought resistance, high survival rate and nursery stock will grow fast. For example, by diluting NAA, IBA and IAA to 10-100ppm weak solution and dipping the cutting base with these kinds of solutions before cutting, or dipping the cutting incision with 500-2000ppm powder, they can all promote rooting. Meanwhile, by using the above solutions in the grafting and mould layering stage, it can also promote the healing of tissues and promote rooting.
b. Control plant type. By spraying paclobutrazol on the ornamental peach tree, it can promote sprout shoot growth, promote flower bud formation as well as plant will become dwarf and compact. When using it, 1.7-3.3g will be prepared into water solution according to the projected area of crown per square meter. Afterwards, it will be sprayed in the circular canal. Besides, this kind of solution will have good effect when it is sprayed in autumn. In addition,150-200ppm paclobutrazol solution can also be sprayed on leaves in the beginning and mid of May. By irrigating soil with 500ppm paclobutrazol solution, it can dwarf azalea plant as well as plant type will become compact and crown will become large.
c. Control dormancy. By spraying 100-5000ppm methyl naphthalene-1-acetate on the crown of fruit trees or ornamental trees, it can promote fallen leaves ahead of time, thus germs will enter dormancy period early as well as it can also improve cold resistance and delay germination in the early spring. For example, it can delay the germination of flower bud and leaf bud of apple tree, pear tree and peach tree 10-15 days, thus it can prevent from being damaged by early frost.
d. Prevent excessive growth and lodging. By spraying 2000-2500ppm B9 water solution on azalea and other flowers, it can dwarf plant, promote branching and improve ornamental value. By inhibiting the growth of hedge terminal bud and lateral bud with high concentration plant growth inhibitor, it can partially replace artificial pruning and save labour force.
e. Induce flowering. By spraying 100ppm ethephon solution on the ornamental fruit nursery stock, it can improve fruit setting rate and accelerate fruit ripening. By evenly spraying 50-100ppm NAA solution, it can delay fruit ripening and extend ornamental period.
f. Prevent disease and prevent blossom drop. By evenly spraying 100-1000ppm CCC solution when the peach flower bud blossoms, it can obviously improve the cold resistance and stress resistance of flower bud as well as flowers will become lush and it can also improve ornamental effect.