The application of plant growth regulator on corn
a. Prevent corn lodging
Ethephon: according to test report, by spraying ethephon on corns, it can promote root development, stalk will become dwarf and strong, increase ventilation in the field, promote precocity as well as the output can be increased by 218.4kg per mu. When the filament is generated in about 1 percent of corns, foliage spray 25-30kg 40 percent of phosphoric acid at 500 times liquid.
Attention: strictly master the working concentration when using ethephon. This is because when the working concentration is too high, it will greatly inhibit the stalk growth and will influence the output; besides, we should also master proper using time and prevent spraying the drugs too early or too late; drugs should be sprayed evenly so as to avoid uneven growth that caused by uneven drug delivery.
Maize roborant: by using maize roborant, it can inhibit stalk internode elongation, promote the thickening of stalk, promote strong root system, lower ear height, improve lodging resistance, shorten growth period and increase hundred-grain weight. During 1 percent of corn heading stage, foliage spray 25L maize robroant diluent under the concentration of 600-800mg/L per mu.
Attention: this kind of drug can be sprayed when the plant height of corn has reached more than 2m; it can only be sprayed 1 time and should by sprayed evenly; it should not be used in corns that have weak growth vigor and short plant type; besides, it should not be mixed with other pesticides or chemical fertilizer.
Sodium nitrophenolate: by spraying sodium nitrophenolate on corns when the male flower has occurred, it can increase corn grain plumpness, increase grain weight as well as can increase output and promote precocity. When removing tassel of corns, foliage spray 50kg sodium nitrophenolate diluent under the concentration of 5000 times per mu.
This kind of drug should be prepared and used at the same time; the working concentration should be strictly controlled, in which 1.4 percent 5000-6000 times liquid of sodium nitrophenolate will be regarded as the most appropriate concentration; it should be sprayed in sunny days and should be sprayed again when it rains after 6h; it can be mixed with acidic pesticide.
c. The application tests of other regulators on corns
Diethyl aminoethyl hexanoate: after spraying diethyl aminoethyl hexanoate in corn tasseling stage, observing the main characters of corn ear parts as well as comprehensively analyzing the applying effect and applying cost, it can be found that by spraying diethyl aminoethyl hexanoate in corn tasseling stage, it will have obvious yield-increasing effect.
Brassinolide: by spraying brassinolide on corns, it can improve reproductive traits of corns, increase setting percentage, promote precocity and will have obvious yield-increasing effect. Besides, we should also pay attention to the flight height of airplane in the aerial spraying operations. After observing the spraying operation, results show that the practical flight height of airplane should not exceed 5m, thus it can make sure that the droplet can rapidly contact with blade surface, prevent drifting and volatilizing of droplet and ensure spraying effect.