主播大秀

Food fanatic Stefan Gates explores the science behind agriculture's most important event, harvest.

For farmers, harvest is the busiest and most important time of the year. To grow good food, and enough of it, farmers need to understand the science behind the harvest.

Our ability to feed ourselves all hinges on the fact that plants can create their own food through the process of photosynthesis. Stefan reveals how we can actually see photosynthesis in action with the use of some simple props. At a massive tomato greenhouse in Kent, Stefan discovers that farmers can artificially create the ideal conditions for photosynthesis to produce a bumper crop of tomatoes, even in winter. He explores how some of our most familiar vegetables - including carrots, onions and the humble spud - are actually a result of plants' own survival strategies, and reveals the biology behind the magic of seeds and how they germinate.

For our fruit harvest to be successful, plants have to reproduce. That's where pollen comes in. Stefan explores the vital role that pollinators like bees and other insects play in our harvest, as well as the reasons why some plants create flowers and fruit. He reveals the surprising importance the cold of winter plays in the development of summer fruit, through the mysterious process of vernalisation.

Farming will always be at the mercy of the weather, but with access to more and more technology, farmers are developing ways of controlling the environment to produce better quality food, all year round. The innovation doesn't stop there. Stefan reveals the ways in which plant breeders can speed up natural selection, handpicking the characteristics they want, and revealing that this process has been an integral part of farming since agriculture began thousands of years ago. Finally Stefan looks at harvest's mega machines and how they have revolutionised modern, large scale farming in recent years.