Question

Read the following statements and find out the incorrect statements.

a. Both a short day plant and a long day plant can flower simultaneously in a given place.

b. Sugar beet, cabbage and carrot are common biennials.

c. Some important food plants, wheat, barley and rye have three kinds of varieties- winter, summer and spring varieties.

d. Vernalisation promotes precocious reproductive development late in the growing season and enables the plant to have sufficient time to reach maturity.

e. Many of the extrinsic factors such as temperature and light, control plant growth and development via PGR.

Answer 1

Incorrect statements
Statement c

Some important food plants, wheat, barley and rye have three kinds of varieties- winter, summer and spring varieties.

Elaboration
Based on the season in which the plant is sown and it flowers, plant are divided into three types:

$\bullet$ Annual plants- Germinate, grow and bloom in one season

$\bullet$ Biennial plants- Germinate, grow and bloom in two seasons

$\bullet$ Perennial plants- Plants that live for several years (more than two seasons)

Elaboration
Annual plants can be further divided into two varieties:
$\bullet$ Spring variety- These plants are sown in spring and harvested in mid summer.

$\bullet$ Winter variety- These plants are sown in autumn, grow over spring and harvested in mid summer.

Wheat, rye and barley have two varieties- spring and winter varieties.
Hence, the given statement is incorrect.

Statement d
Vernalisation promotes precocious reproductive development late in the growing season and enables the plant to have sufficient time to reach maturity.

Elaboration
Vernalisation is defined as dependency of flowering of plants quantitatively or qualitatively on exposure to low temperature. It prevents precocious reproductive development and provides ample time to achieve proper growth and maturity.
Hence, the given statement is incorrect.