There are a lot of stresses on the transplanting of watermelon seedlings. Many watermelon growers have many misunderstandings in transplanting and planting. When is the watermelon seedling transplanted and planted best? do we need to care something?
Watermelon seedling transplanting precautions
Seedlings are generally started around the Spring Festival, and transplanting and planting began in March, with slight differences in different regions. Robust seedlings have a direct impact on planting survival, flowering fruit setting and yield. However, the temperature is low before and after the Spring Festival, the rainy and snowy weather, and the light is weak, which is unfavorable for the growth of the seedlings.
Do well in insulation measures, such as heating the bulb or electric heating wire, cover the grass mat on the grass shed at night, so that the temperature of the seedbed is not lower than 10 °C; strengthen the humidity control in the shed, uncover the small shed film, and let the nutrient water hold at 65%. Left and right, the relative humidity of the air in the shed is 50%~60%. The seedling age is 25 to 30 days, and it is not good either too early or too late.
Before transplanting the melon seedlings, in order to adapt the seedlings cultivated under the protective facilities to the environment of the field, it is necessary to cool and control the melon seedlings about one week before preparation for planting, that is, refining the seedlings, and cultivating the seedlings to promote the aging of the watermelon seedlings To improve adaptability and resistance. The transplanting of watermelon seedlings should be carried out in the morning with good sunny weather, and the ground temperature should be raised as much as possible to promote the rapid growth of new roots and slow seedlings. If the low temperature weather planting seedlings or continuous low temperature weather after planting seedlings, it is easy to cause watermelon roots or dead seedlings. Generally, at a temperature of 10 cm, it can be colonized when it reaches 15 °C or higher.
The depth of planting of melon seedlings is about 1 cm in the soil buried on the surface of nutrient soil. The soil temperature and poor ventilation are too deep, and it is not easy to moisturize too much. These will affect the development of watermelon roots, resulting in slow growth of watermelon. When the grafted seedlings are planted, the grafting interface should be at least 1~2 cm above the ground. Planting too deep makes the hypocotyl part of watermelon (scea) contact the soil and produce self-generated roots, making grafting meaningless.
One day before planting, the water can be poured once to prevent the watermelon seedlings from dying when the seedlings are mixed. At the same time, the seedbed sprays 79% of methyl thiophanate-wet WP 800 times solution and 40% dimethoate emulsifiable concentrate once to prevent pests and diseases, eliminating the trouble of spraying after transplanting the field.
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The automatic biochemical analyzer is an instrument that measures a specific chemical composition in body fluids according to the principle of photoelectric colorimetry. Due to its fast measurement speed, high accuracy and small consumption of reagents, it has been widely used in hospitals, epidemic prevention stations and family planning service stations at all levels. The combined use can greatly improve the efficiency and benefits of routine biochemical testing.
principle
The automatic analyzer is to automatically run all or part of the steps of sampling, mixing, warm bath (37°C) detection, result calculation, judgment, display and printing results and cleaning in the original manual operation process. Today, biochemical tests are basically automated analysis, and there are fully automatic biochemical analysis systems designed for large or very large clinical laboratories and commercial laboratories, which can be arbitrarily configured according to the laboratory's testing volume.
Whether it is the fastest-running (9600Test/h) modular fully automatic biochemical analyzer today, or the original manual-operated photoelectric colorimeter for colorimetry, the principle is the use of absorption spectroscopy in spectroscopic technology. It is the most basic core of the biochemical instrument.
Optical system: is a key part of ACA. Older ACA systems used halogen tungsten lamps, lenses, color filters, and photocell assemblies. The optical part of the new ACA system has been greatly improved. ACA's beam splitting system can be divided into front splitting and rear splitting due to different light positions. The advanced optical components use a set of lenses between the light source and the cuvette to convert the original light source. The light projected by the lamp passes through the cuvette to bring the beam to the speed of light (unlike traditional wedge beams), so that the spot beam can pass through even the smallest cuvette. Compared with traditional methods, it can save reagent consumption by 40-60%. After the spot beam passes through the cuvette, the spot beam is restored to the original beam through this group of restoration lenses (wide difference correction system), and is divided into several fixed wavelengths (about 10 or more wavelengths) by the grating. The optical/digital signal direct conversion technology is used to directly convert the optical signal in the optical path into a digital signal. It completely eliminates the interference of electromagnetic waves to the signal and the attenuation in the process of signal transmission. At the same time, the optical fiber is used in the signal transmission process, so that the signal can achieve no attenuation, and the test accuracy is improved by nearly 100 times. The closed combination of the optical path system makes the optical path without any maintenance, and the light splitting is accurate and the service life is long.
Constant temperature system: Since the temperature of the biochemical reaction has a great influence on the reaction results, the sensitivity and accuracy of the constant temperature system directly affect the measurement results. The early biochemical instruments used the method of air bath, and later developed into a dry bath with constant temperature liquid circulation which combines the advantages of dry air bath and water bath. The principle is to design a constant temperature tank around the cuvette, and add a stable constant temperature liquid that is odorless, non-polluting, non-evaporating and non-deteriorating in the tank. The constant temperature liquid has a large capacity, good thermal stability and uniformity. The cuvette does not directly contact the constant temperature liquid, which overcomes the characteristics of the water bath type constant temperature being susceptible to pollution and the uneven and unstable air bath.
Sample reaction stirring technology and probe technology: The traditional reaction stirring technology adopts magnetic bead type and vortex stirring type. The current popular stirring technology is a stirring unit composed of multiple groups of stirring rods that imitate the manual cleaning process. When the first group of stirring rods is stirring the sample/reagent or mixed solution, the second group of stirring rods performs high-speed and high-efficiency cleaning at the same time. The set of stirring bars also undergoes a warm water washing and air drying process at the same time. In the design of a single stirring rod, a new type of spiral high-speed rotating stirring is adopted, and the rotation direction is opposite to the spiral direction, thereby increasing the stirring force, the stirred liquid does not foam, and reducing the scattering of light by microbubbles. Reagent and sample probes are based on the principle of early capacitive sensing, but slightly improved to increase the alarm of blood clots and protein clots, and re-test results according to the alarm level, reducing sample aspiration errors and improving the reliability of test results. . Large-scale biochemical instruments can detect more than 1,000 tests per hour, so automatic retesting is very important. Subjective evaluation of test results and manual retesting can no longer meet clinical needs.
Other aspects: barcode recognition of reagents and samples and computer login. Due to the lack of barcode recognition function of early biochemical instruments, there are more opportunities for errors. In recent years, both imported and domestic chemical instruments have adopted barcode detection. The use of this technology in biochemical instruments has provided technical support for the development of high-speed ACA, and also made the instrument quite supportive. The software development is simple and easy, therefore, barcode detection is the basis for the intelligence of the instrument. Open reagents, as an important factor for hospitals to choose models, whether the instrument supports open reagents is very important. After the reagents are opened, hospitals and scientific research units can choose their own reagent suppliers, and have a greater degree of freedom in measuring the price, the reliability of the test results, and the validity period of the reagents. Ion Selective Electrode Analysis Accessory (ISE), human serum and urine electrolyte indicators are very important, and hospitals can save money by adding ISE to the ACA system.
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