VEGETATIVE MATERIALS

VEGETATIVE MATERIALS

0
131 Views

VEGETATIVE MATERIALS 

These are plant parts which have the ability to produce roots, they grow and develop in to new plants.

Plant parts such as leaves, roots or stems can be used for planting as long as they are capable of rooting.

 

Advantages of using vegetative materials for planting.

  • Crops originating from vegetative materials matures faster than those from seeds.
  • The crops shows uniformity in such qualities as disease resistance, seed size, colour, keeping or storing quality and chemical composition.
  • It is possible to produce many varieties of compatible crops on the same root stock.
  • Use of the vegetative materials is easier and faster, especially where seeds show prolonged dormancy.
  • The resulting plant has desired shape and size for ease of harvesting and spraying.
  • It facilitates the propagation of crops which are seedless or those that produce seeds which are not viable or have a long dormancy period.
  • Such crops include sugar-cane, bananas, Napier grass and others.

Disadvantages.

  • Vegetative propagation does not result in new crop varieties.
  • Keeping the materials free of diseases is difficult.
  • Materials cannot be stored for long.
  • The materials are bulky and therefore difficult to store and transport.

Plant parts used for vegetative propagation.

  1. i) Bulbils.
  • These are tiny sisal plants produced in the inflorescence almost at the end of the plant growth cycle.
  • They resemble the mother plant except that they are smaller in size.
  • They are produced by the branches of the sisal pole.
  • When manure they mature they develop rudimentary roots and fall off to the ground just below the pole.
  • They are the collected and raised in the nurseries before they are transplanted t\o the main field.
  • One sisal pole may produce as many as 3,000 bulbils. They are usually 10cm long. They make good planting materials and are better than sucker
  1. ii) Splits
  • These are plantlets divided from the existing mother plant with complete with complete leaves and rooting system.
  • They are used to propagate most pasture grasses and pyrethrum.
  • Pyrethrum splits are raised first in nursery and then transplanted to the field.

iii) Crowns and slips

  • These are materials used to propagate pineapples
  • Crowns are born on top of the fruits and are broken off and prepared for planting.
  • They are more preferred to suckers because they give uniform growth and take two years to reach maturity.
  • Slips are borne to the base of the pineapple fruits.
  • They are cut and prepared for plantings.
  • Their growth rate is faster than for crowns giving average uniformity.
  • They take 22 months from planting to maturity.
  • Crowns and slips are planted in the nurseries first before transplanting to the main seed bed.
  1. iv) Suckers
  • These are small plants that grow from the base of the main stem.
  • They have adventitious roots which grow quickly when planted to form a new plant.
  • They are used to propagate bananas, sisal, and pineapples.
  • When planted, suckers give uneven growth leading to maturity at different times.
  • They should be planted when they are young.
  1. v) Tubers
  • These are underground food storage organs which are short and thick.
  • They are used as vegetative propagation materials because they sprout and produce roots for growth.
  • There are mainly two types of tubers, the stem and root tubers.
  • Root tubers develop from the thickening of the adventitious roots.
  • Root tubers are not commonly used for propagation since they produce weak stems.
  • A good example of a root tuber is the sweet potato.
  • On the other hand stem tubers have some auxiliary buds which are sometimes referred to as ‘eyes’.
  • These eyes sprout to produce stems which grow into plants. Stem tubers are therefore swollen stems with scales leaves.
  • A good example of a stem tuber is Irish potato.
  1. vi) Vines.
  • These are soft wood cuttings which produce roots easily upon planting to give rise to new plants.
  • They are cut from the mother plants and planted directly into the field.
  • Soft wood cuttings (vines) are taken from rapidly growing shoots.
  • The soft upper parts of the shoots are preferred.
  • When preparing the cuttings, some leaves and nodes are included.
  • Roots are produced from the nodes.

vii) Cuttings and setts

  • Cuttings are portion of plants parts which are cut and then planted.
  • They may be from stems, roots or leaves.
  • A stem cutting must have a bud which develops into shoot.
  • The root cutting must have an eye. Cutting must have an eye.
  • Cuttings must produce leaves as soon as possible so that they can start making their own food.
  • Sometimes cuttings are induced to produce roots by use of rooting hormones.
  • Once the cuttings have developed roots, they give rise to new plants.
  • In some crops, the cuttings are big enough to be planted directly to the main seedbed whereas there are some plants whose cuttings are first raised in special nurseries before they are transplanted to the seedbed.
  • The cuttings of Napier grass and sugar-cane are planted directly on the seedbed but those of tea; have to be raised in special nursery before they are transferred to the seed bed.
  • Examples of crops which are propagated by use of stem cuttings include: tea, cassava, and sugar-cane and Napier grass.
  • The stem cuttings used to propagate sugar-cane are known as ‘setts’. Setts are stem cuttings which have 3-5 nodes are usually 30-45 cm long.

0

Post Comment