What will happen if field is not ploughed before sowing the seeds? Give any two disadvantages. [DAV2006]How are perishable food items stored on a commercial scale?Why should excessive supply of water be avoided?What are weeds?

Disadvantages: Seeds cannot be sown at proper depth. Water and air holding capacity of soil will be poor. Perishable food items can be stored in deep freezers and cold storages. Roots get damaged and the plants die because of excessive supply of water. They are unwanted plants which grow along with the cultivated plants.