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How the Cyclone is formed?

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  Three things are important for the cyclone formation 1.Sun's heat 2. Sea water 3. Earth rotation  Before we enter into the topic we have to know some basic informations  The sun's temperature is higher in the middle of the earth when compared to the polar regions, because the equator region is closer to the sun and the sun rays are first hits the equator region when compare to the polar region. The region between the Tropic of cancer and Tropic of capricorn is called as Tropical region and the cyclones are formed in the tropical region only. When the sun fall on the equator region,the sea water warm and then it leads to evaporation and it create the low pressure in the area. We are all know that the air moves from the high pressure to low pressure. To fill the void(empty space) in the area, the air moves from high pressure to low pressure area and the cyclone forms.  So lets go deep into how the air moves from the high pressure to low pressure and how the cyclone is formed.

Sheath blight of rice caused by R.solani and its management

 Sheath blight of rice caused by R.solani and its management Sheath blight of rice from Yuvaraj M

Management of plant virus

                                                     MANAGEMENT OF PLANT VIRUS  • Many plant pathogens, particularly fungi, can be controlled by the application of chemicals which interfere in some way with the metabolism of the invading pathogen, and so prevent disease.  • Unfortunately, these methods cannot be used so extensively to control plant viruses.  Prevention, or at least measures, for the control of viruses, involves :  1. Elimination of sources of virus.  2. Elimination of the virus from infected plants. 3. Control of vectors.  4. Breeding for resistance and the use of cross-protection methods.  1. Elimination/Removal of source of virus  ❖ Living host for the virus              Removal of perennial and annual weed host  ❖ Plant remains Plant remains in the soil, or attached to structures such as greenhouses, may act as a mechanically transmitted virus and act as source of infection for the next crop(TMV)  ❖ Rouging Removal of diseased plants from the field. If the spread