The cycle of plant growth

Active or developmental growth. It is difficult to differentiate between the seeding stage and that of active growth. During active growth the plant should be so cultivated and fertilized that there is no interruption in its vital growth processes. It is in this stage that the small-grain plant heads and the corn and sorghum plants elongate rapidly and prepare for the production of the flowers. A drought at this time may greatly reduce the yield. The strong vigorous plant is much less suffering damage from the many plant diseases such as black stem rust and the smuts, and from other parasitic organisms.

Reproduction. It is Nature’s rule that the plant perpetuate its kind. In the annual seed-bearing plant, the formation of seed is essential to reproduction. Early seeding and rapid growth are desirable to avoid the hot summer weather at the time when the grain crop produces its flowers.

Most of the small-grain crops are self-pollinated, i.e. the flowers contain both male and female organs, and fertilization usually occurs within the individual flower of the grain crops, corn and rye are cross-pollinated, pollen from one plant is carried by the wind to the flowers of another plant. The sorghums have both male and female flowers on the flowering stalk, and while self-pollinated is normally more frequent than cross-pollination considerable cross-pollination may occur.

Maturation. Following pollination and fertilization, the embryo develops and the seed is formed. During the period of active development, the seed contains much water, but the water content is gradually reduced until the seed reaches a stage when it may be sail said to be mature.

Dormancy. The period of dormancy is a natural follow-up of maturation. Some seeds have a period of after ripening and will not germinate even when placed under favourable conditions. Generally this period is short for the grain crops, although trouble may be experienced where winter wheat is seeded soon after harvest.

Упражнение 9. Ответьте на вопросы.

1. How should be the plant cultivated during active growth?

2. Have the sorghums male or female flowers?

3. When the seed contains much water?

 

Вариант 4

Упражнение 1. Заполните пропуски соответствующими личными и притяжательными местоимениями.

1. I don’t know this car. Do you know …?

2. He likes box. It’s … favorite sport.

3. We have a house. … house is in the village.

4. My uncle isn’t very friendly. I don’t like ….

5. Our friends live in England, but … children study in Russia.

 

Упражнение 2. Задайте пять видов вопросов к предложению.

This farmer has 5 flower-beds with carrots, 4 flower-beds with sugar beets.

 

Упражнение 3. Напишите множественное число следующих существительных.

Quality, rainfall, flax, rye, barley, livestock, wheat, selection, seedling, weed.

 

Упражнение 4. Переведите предложения на русский язык, обращая внимание на степени сравнения прилагательных и наречий и сравнительные конструкции.

1. His house is larger than yours.

2. The elephant is as clever as a dog.

3. It is the most interesting book.

4. The boy is as tall as his elder brother.

5. This flower is the smallest in your garden.

 

Упражнение 5. Заполните пропуски словами much, many, a lot of.

1. Wolf likes to eat … meat.

2. A poor hare has … enemies.

3. I have not … time. I must do my homework.

4. There are … people in the supermarket.

5. Do not eat … sweet!

 

Упражнение 6. Переведите на русский язык следующие пары слов.

Digestible protein, self-pollination, genetic make up, growing season, growth habit, spring sowing, dormant stage.

 

Упражнение 7. Раскройте скобки, обращая внимание на употребление глагола в Passive Voice.

1. Bread (to eat) every day.

2. After the fire the streets (to make) wider.

3. “Gone with the Wind” (to write) by Margaret Mitchell.

4. His report (to look) tomorrow.

5. The newspapers (to sell) at 5 o’clock.

 

Упражнение 8. Прочитайте и переведите текст письменно.