Bigger and better
How do plants form seeds?
If you break open a sweet pepper, you’ll see dozens of tiny seeds that can grow into new pepper plants. Many plants reproduce by forming seeds. When planted, a seed develops into a new plant of the same kind. How do seeds form? The seeds of fruits and vegetables develop in flowers.
heads of wheat seed form at the top of each wheat stem .Each head is made up of clusters of flowers.
How Seeds Form?
How would you describe a flower? Would you use words like beautiful, colorful, fragrant, delicate? You probably wouldn’t say factory, but that’s a good word to describe a flower. Flowers are like factories that manufacture seeds.
Take a close look at this wheat flower as you read about the mass production of seeds. Most flowers have both the male and female machinery needed to produce seeds. The male parts are long, skinny stalks called stamens. The tips of the stamens contain millions of tiny pollen grains. Pollen can contains on the male sex cells, or sperm.
The stamens should be surrounded the pistil, or female part of the flower. The top part of the pistil is usually sticky. The bottom part, or ovary, contains one or more ovules. Each ovule holds a female sex cell, or egg. When an egg and a sperm unite, a seed is formed. But before a seed is formed, pollen must get to the pistil. The moving of pollen from a stamen to the sticky part of the pistil is called pollination . This wheat flower pollinates itself. But sometimes pollen from one flower is carried by wind to another flower. Insects help pollinate other kinds of flowers. How? Pollen gets stuck to an insect’s body when it lands on a flower. When the insect visits another flower, the pollen can rub off onto the sticky part of the pistil.
After pollination, a tube grows down from a pollen grain stuck to the pistil. A sperm cell from the pollen grain travels down the tube and joins with an egg inside an ovule. Then the egg cell develops into a seed-a grain of wheat! In other kinds of flowers, the ovary becomes a thick fruit that covers and protects the seed or seeds. Most of the vegetables in the picture are fruits.
Hybrids of Corn
People can control pollination to produce new varieties of plants.
What pollinated the plant that produced this tasty ear of corn wind, an insect? It may have been a scientist!
The varieties of corn shown have different characteristics, or traits. Scientists can produce certain traits in corn and other plants by growing hybrids. A hybrid is an offspring of parents with different traits. To produce hybrids, scientists cross, or mate, two varieties of plants by controlling pollination. The hybrid produced by a cross has desirable traits from both parents.
Making hybrids
Scientists collect pollen from the tassel of one plant and transfer the pollen to the silk of the second plant. The second plant produces seeds, which grow into hybrid plants.
Hybrids of corn
Scientists have produced many new varieties of corn, especially hybrids of white and yellow sweet corn. Hybrids of popping corn make wholesome snacks. Hybrids of decorative corn-with red, orange, yellow, and blue kernels make festive decorations.
Hybrid seeds
Many kind of hybrid seeds are available and new hybrids are developed every year
New Foods from Hybrids
Did you ever wonder why scientists spend so much time developing new varieties of plants? Growing hybrids solves a lot of problems for gardeners and farmers. Thanks to hybrids, farmers can grow bigger, healthier crops. That’s very important in the world today, because the growing population needs a plentiful supply of nutritious foods. Growing hybrids can also help protect the environment. How? Some hybrids don’t get certain are not as likely to be eaten by certain crop pests. When farmers plant these hybrids, they don’t need to use as many chemical pesticides on their crops.
The vegetables on these pages are grown from hybrid plants. The peas come from pea plants that are resistant to a disease-called downy mildew-caused by a fungus. By growing this hybrid, a farmer doesn’t have to use a fungicide or chemical that kills the fungus. These carrots not only look good-they’re good for you!
They’re a hybrid that contains more carotene, a source of vitamin A. Farmers will tell you that tomato plants are slow growers. They need long summers to bear fruit. But this tomato was picked from a hybrid plant that produces tomatoes in a shorter period of time. It’s grown by farmers and gardeners who live in the northern parts of North America, where summers are short. On the map, these northern regions are shown in blue.
