How to diagnose remedy for potassium deficiency in watermelon
In the absence of potassium in potassium deficiency, the plants grow slowly, the stems are weak, the leaves are dark and dull, the leaves are curled to the back, and the leaves of the lower nodes are yellowed. Symptoms usually develop from the bottom up. In severe cases, the heart leaves become pale brown, and even the burnt shape, resulting in difficulty in fruit setting, small fruit shape, reduced sugar content, and decreased quality. Remedial measures: First, use 5 to 10 kg of potassium sulfate per mu (3 to 5 kg per mu in seedling stage, 8 to 10 kg per mu after stretching) or 30 to 60 kg in grass ash; secondly, 0.4 Foliar application of %~0.5% potassium sulfate solution. Disclaimer: Some articles on this website are transferred from the Internet. If legal rights of third parties are involved, please inform this website. phone
Centrifugal tubes are generally disposable experimental devices and are not recommended for repeated use. In order to save money, PP centrifugal tube can be reused according to the situation, but it needs to be thoroughly disinfected by high temperature and high pressure to ensure the scientific results of the experiment. PE material centrifugal tube, can not be high temperature and high pressure disinfection.
We all know that in plastic centrifugal tubes, commonly used materials are polyethylene (PE), polycarbonate (PC), polypropylene (PP) and so on. The performance of polypropylene PP tube will be relatively good. Therefore, we should consider the plastic centrifugal tube of polypropylene as far as possible when selecting plastic centrifugal tube.
Use method of centrifugal tube: Lab Consumables Plastic Centrifuge Tube,50Ml Centrifuge Tube,15Ml Centrifuge Tube,2Ml Centrifuge Tube Changchun ZYF science and technology CO.,LTD , https://www.zyf-medical.com
1. Because the graduated centrifugal tube is a metering device, it must be cleaned and dried before use.
2. When reading, be sure to observe the bending liquid level correctly, otherwise it will introduce a certain error.
3. When used, the number of centrifugal tubes should be determined according to the model of the centrifuge. For example, if a centrifuge with two tubes is used for a single test, the same volume of liquid must be loaded into the other centrifugal tube to maintain balance.
4. The centrifuge tube and the centrifuge casing should be compatible. Pipe should not be too long, otherwise it is easy to break when rotating. But it is not easy to be too short, too short pipe is unstable when rotating in the air, and easy to cause breakage. Too thick sleeve not into, too thin rotation instability, round mouth should be greater than the inner diameter of the casing.
5. After the centrifugal tube is placed into the casing of the centrifuge for stratified separation, it should be stopped naturally when it stops rotating, and it should never be forced to stop by external force.
Precautions for centrifugal tube:
When we use centrifugal tube, do not use a tube many times, pay attention to the sample volatilization and some radioactive or corrosive sample leakage; In the storage process, it is necessary to seal well; It is necessary to prevent the deformation of centrifugal tube in the process of use.