Symptoms use pesticides or herbicides, above a certain concentration, can form abnormal color of the leaf class, such as white spots or brown spots, young shoots and roots curled or thickened, plant growth is inhibited, the leaves are shortened or the grains are exposed; If the fertilizer is used excessively or the pesticide is applied too much, the seeds will always germinate or die after being killed, the remaining seedlings will be dwarfed, and the leaves will turn yellow or die.
Excessive application of dichlorvos, trichlorfon, phoxim, 2.4-D and chemical fertilizers may cause the above symptoms. Excessive soluble nitrogen, potassium and other fertilizers close to the seed will inhibit seed germination or death after seedling emergence. Apply or drift 2.4-D. The leaves can be curled into onion leaves, the lower stems and leaves are clustered together, and the aerial roots are not in contact with the soil; excessive application of phoxim can whiten the leaves partially or mostly, causing the leaves to dry and freeze like a freeze. The mechanism of chlorophyll and other organophosphorus pesticides causing discoloration and other phytotoxicity is that the hydrophobic organophosphorus pesticide is adsorbed by the green leaf body or surrounding tissues, causing the chloroplast function to fluctuate, thereby hindering the electron conduction reaction, ie, Hill reaction, inhibition. Photosynthetic, discoloration occurs, the more serious the phytotoxicity, the lower the carbohydrate content in the body and the relative increase in total nitrogen. Production is different due to conditions such as corn variety, developmental stage and environmental factors. Different degrees of phytotoxicity will cause the leaves to die, discolor, deformity and so on.
Control method (1) Formulated fertilization technology, timely and appropriate application, not excessive. (2) When using herbicides, strictly select the variety and master the dosage, avoid the concentration is too high, and should not be sprayed directly in the flare period. (3) Do not use sensitive insecticides such as trichlorfon and dichlorvos in corn fields, and strictly control the dosage when applying phoxim to control underground pests. (4) If the concentration is too high, it should be watered immediately. (5) After the occurrence of phytotoxicity, it is necessary to strengthen management. (6) Spraying Fengbao I type active liquid fertilizer 400~500 times if necessary.
Liu Huimin, Agricultural College of Huaxian County
Excessive application of dichlorvos, trichlorfon, phoxim, 2.4-D and chemical fertilizers may cause the above symptoms. Excessive soluble nitrogen, potassium and other fertilizers close to the seed will inhibit seed germination or death after seedling emergence. Apply or drift 2.4-D. The leaves can be curled into onion leaves, the lower stems and leaves are clustered together, and the aerial roots are not in contact with the soil; excessive application of phoxim can whiten the leaves partially or mostly, causing the leaves to dry and freeze like a freeze. The mechanism of chlorophyll and other organophosphorus pesticides causing discoloration and other phytotoxicity is that the hydrophobic organophosphorus pesticide is adsorbed by the green leaf body or surrounding tissues, causing the chloroplast function to fluctuate, thereby hindering the electron conduction reaction, ie, Hill reaction, inhibition. Photosynthetic, discoloration occurs, the more serious the phytotoxicity, the lower the carbohydrate content in the body and the relative increase in total nitrogen. Production is different due to conditions such as corn variety, developmental stage and environmental factors. Different degrees of phytotoxicity will cause the leaves to die, discolor, deformity and so on.
Control method (1) Formulated fertilization technology, timely and appropriate application, not excessive. (2) When using herbicides, strictly select the variety and master the dosage, avoid the concentration is too high, and should not be sprayed directly in the flare period. (3) Do not use sensitive insecticides such as trichlorfon and dichlorvos in corn fields, and strictly control the dosage when applying phoxim to control underground pests. (4) If the concentration is too high, it should be watered immediately. (5) After the occurrence of phytotoxicity, it is necessary to strengthen management. (6) Spraying Fengbao I type active liquid fertilizer 400~500 times if necessary.
Liu Huimin, Agricultural College of Huaxian County
ã€Comment】 ã€Print this article】 ã€Close this page】 ã€Large, medium and small】
Plastic Seal,High Security Seal,Security Seal
WENZHOU GCSEAL CO. LTD. , http://www.sealsshipping.com