Residual phytotoxicity The phytotoxicity is characterized by the fact that after application, the medicinal agents that do not cause phytotoxicity to the season crops, and which remain in the soil, cause phytotoxicity to crops that are more sensitive to squatting. For example, after the use of simazine herbicide in corn fields, it often causes phytotoxicity to crops such as beet, beans and fruit trees. The phytotoxicity is mostly manifested in the germination or seedling stage of the seed. The light roots, buds and other parts of the light brown rot, affecting normal growth, and the rotted buds are severely rotted, reducing the emergence rate or not emerging at all. Because this phytotoxicity is easily confused with fertilizers, it is necessary to understand the cultivation management and pesticide use of the former stalks and soil testing before the diagnosis to prevent misdiagnosis. 2. Chronic phytotoxicity This kind of phytotoxicity, the symptoms can not be immediately expressed after application, have a certain incubation period, such as growth retardation, fruit and flavor deterioration. Because of this phytotoxicity, it is easily confused with other physiological diseases. Therefore, it can be diagnosed by understanding the occurrence of pests and diseases, the type, quantity, area of ​​the pesticides and the comparison with the plants that are not normally applied. 3. Acute phytotoxicity This phytotoxicity has the characteristics of rapid occurrence and obvious symptoms, and symptoms usually appear within a few hours to several days after application. Generally, the crop leaves are spotted, perforated, burnt, curled, deformed, withered, yellowed, chlorotic or whitened. The damage of the affected part is characterized by short and coarse roots, weak root hair, yellowing or thickening of the root bark, and rot, etc. Pesticides or pesticides are used for improper seed treatment; plants are damaged, which are characterized by falling flowers, buds, fruit deformities, small, spots, brown fruit rust, fruit drop and so on.
High speed shutter door is a rapid operating, anti-crash shutter door for indoor application . The most advantage of this door is that the opening/closing speed can reach to 0.6-1.8m/s, really fast action a lot than tranditional rollling shutter door. short opening and closing times reduce cooling loss, avoid airflow and enable a smooth operating procedure. They can also be designed in larger dimensions for the mining and aircraft industries.
High speed door can be easily installed, economical,quiet and efficient with electromechanical drive.
This door quickly though in/out open gate, ideal for warehouses,factories, hangars use, widths can be from 2m to 20 meters.
The material of this door are variety: PVC curtain to keep the insdie clean, heavy duty aluminum door with wind-resisitant function can wrok in heavy windy weather, and also the freezer door can be used in cold warehouse or somewhere like that.
Including models are:PVC High Speed Door, Aluminum Spiral High Speed Door, Self-Recovery repair door, Cold Storage Room Fast Door.
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