The plant hormone used to destroy weeds in a field is

Plants follow different pathways in response to environment or phases of life to form different kinds of structures. This ability is called

Inhibitory substances in dormant seeds cannot be removed by subjecting seeds to

A species which was introduced for ornamentation but has become a trouble some weed in

Which of the following is not an inhibitory substance governing seed dormancy?

The process of growth is maximum during

Removal of shoot tips is very useful technique to boost the production of tea leaves. This is because

In order to increase the yield of sugarcane crop, which of the following plant growth regulators should be sprayed?

It takes very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?

Fruit and leaf drop at early stages can be prevented by the application of

The Avena curvature is used for bioassay of

You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?

You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?

Auxin can be bioassayed by

Dr. F Went noted that if coleoptile tips were removed and placed on agar for one hour, the agar would produce a bending when placed on one side of freshly cut coleoptile stumps. Of what significance is this experiment?

Senescence as an active developmental cellular process in the growth and functioning of a flowering plant, is indicated in

Some of the growth regulators affect stomatal opening. Closure of stomata is brought about by

Which one of the following growth regulators is known as ‘stress hormone’?

During seed germination its stored food is mobilised by

Phototropic curvature is the result of uneven distribution of

Coiling of graden pea tendrils around any support is an example of

One of the synthetic auxin is

Which one of the following acids is a derivative of carotenoids?

Opening of floral buds into flowers, is a type of

Foolish seedling disease of rice led to the discovery of

Which one of the following pairs, is not correctly matched ?

How does pruning help in making the hedge dense?

An enzyme that can stimulate germination of barley seeds is

Treatment of seed at low temperature under moist conditions to break its dormancy is called

Cell elongation in internodal regions of the green plants takes place due to

Differentiation of shoot is controlled by

Plants deficient of element zinc, show its effect on the biosynthesis of plant growth hormone

Hormone responsible for senescence is

Which of the following prevents fall of fruits?

Which breaks bud dormancy of potato tuber?

What reason will you assign for coconut milk used in tissue culture?

The closing and opening of the leaves of Mimosa pudica is due to

Which combination of gases is suitable for fruit ripening?

A plant hormone used for inducing morphogenesis in plant tissue culture is

Gibberellins induce

Ethylene gas is used for

Removal of apical bud results in

Movement of auxin is

Klinostat is employed in the study of

Cytokinins

Which is employed for artificial ripening of banana fruits?

Bananas can be prevented from over-ripening by

Dwarfness can be controlled by treating the plant with

A chemical believed to be involved in flowering is

Abscisic acid causes

The hormone responsible for apical dominance is

Which of the following movement is not related to auxin level?

Phototropic and geotropic movements are linked to

Phytohormones are

Highest auxin concentration occurs

Abscisic acid controls

Mowing grass lawn facilitates better maintenance because

Leaf fall can be prevented with the help of

Which of the following hormones can replace vernalisation?

Leaves of many grasses are capable of folding and unfolding because they

Movement of leaves of sensitive plant, Mimosa pudica is due to

Out or excised leaves remain green for long if induced to root or dipped in

Hormone primarily connected with cell division is

The site of perception of light in plants during photoperiodism is

What is the site of perception of photoperiod necessary for induction of flowering in plants?

Phytochrome is a

A few normal seedlings of tomato were kept in a dark room. After a few days they were found to have become white-coloured like albinos. Which of the following terms will you use to describe them?

Importance of day length in flowering of plants was first shown in

The wavelength of light absorbed by Pr form of phytochrome is

One set of a plant was grown at 12 hr day and 12 hr night period cycles and it flowered while in the other set night phase was interrupted by flash of light and it did not produce flower. Under which one of the following categories will you place this plant?

Which one is a long-day plant?

Proteinaceous pigment which control activities concerned with light

The method that renders the seed coat permeable to water so that embryo expansion is not physically retarded, is

The response of different organisms to environmental rhythms of light and darkness is called

What will be the effect on phytochrome in a plant subjected to continuous red light?

If a tree, flowers thrice in a year (Oct., Jan. and July) in Northern India, it is said to be

In short-day plants, flowering is induced by

Flowering dependent on cold treatment is

Which one increases in the absence of light?

Phytochrome is involved in