The main idea of paragraph two is

Constanza is one of those farmers. His some computer makes the connection with Satellite Space-eye. He asks to see a picture of the field in the south-west corner of his farm. The picture appears on a TV screen. It is a picture of a green wheat field. Everything looks fine. He then asks the computer to show the same area, but in colours. The colours show the different temperatures in the field. He knows healthy wheat plants will all be green. The TV screen blinks and a beautiful picture appears. It has many shades of blue, red, and green.

The main idea of paragraph two is ….