MODULE 6

Question 1

Plant growth regulators

Answer 1

Organic compounds other than nutrients which in minute amount promote, inhibit or modify plant growth and development. Either synthetic or natural

Question 2

Phytohormones

Answer 2

naturally occurring plant growth regulator.

Question 3

Classes of PGR:

Answer 3

Auxins, gibberellins, cytokinins, abscisic acid, ethylene

Question 4

Training

Answer 4

techniques that direct or modify the growth of plants in terms of canopy size, shape and direction

Question 5

Trellising

Answer 5

provision of support to viny crops and other crops that could not stand without support

Question 6

Types of trellises

Answer 6

Fence, Overhead, A-type, T-type, Single, Teepee

Question 7

Pruning

Answer 7

judicious removal of plant parts to achieve specific objectives

Question 8

Pinching

Answer 8

removing terminal shoot of young plant to encourage spreading canopy growth and/or keep the tree dwarf e.g. coffee, lanzones

Question 9

Bending

Answer 9

Coffee – to produce multiple vertical shoots, thus increase the number of bearing lateral branches

Question 10

Preventive pruning

Answer 10

removal of dead, insect-infested and diseased plant parts

Question 11

Formative pruning

Answer 11

to modify shape of canopy e.g.
Topiary

Question 12

Corrective pruning

Answer 12

removing excess shoots that interfere with light penetration and aeration within the tree canopy

Question 13

Rejuvenative pruning

Answer 13

removing most of the shoots in order to reinvigorate an old or unproductive tree

Question 14

Desuckering

Answer 14

Done in bananas to remove excess suckers

Question 15

Cutting out

Answer 15

removal of entire branch or shoot such as in corrective and preventive pruning

Question 16

Cutting back

Answer 16

removal of portion of branch or shoot such as in formative pruning

Question 17

Stubbing

Answer 17

a severe form of cutting back such as in rejuvenative pruning

Question 18

Why is rejuvenation required?

Answer 18

Unproductive trees can’t be induced to flower because of canopy overlapping

Question 19

How are windbreak trees planted?

Answer 19

In single or double rows near the fence line and within the orchard

Question 20

Important role of windbreak

Answer 20

to reduce windspeed and to protect the crop from damage

Question 21

Dense canopy of windbreak trees

Answer 21

a dense canopy provides more protection against strong winds

Question 22

Height of windbreak trees

Answer 22

tall windbreaks protects a larger area and can reduce wind speed up to 20x its height

Question 23

Pointers in windbreak establishment

Answer 23

• Rows must be oriented perpendicular to wind direction
• The first and last rows should be short to medium; tall ones at the middle row