Botany lecture notes

Economic Importance of Gymnosperms (Short Notes)

economic importance of gymnosperms

Economic Importance of Gymnosperms

The Gymnosperms are with high economic importance to mankind. For easy understanding, the economic importance of Gymnosperms can be categorized in the following heads:

(1).      Food Value

(2).      Medicinal Value

(3).      Timber Value

(4).      Source of Oil

(5).      Industrial Value

(6).      Ornamental Value

(7).      Other Uses

gymnosperms economic aspects

(1). Food Value

Ø  Cycads are a good source of Starch.

Ø  ‘Sago’ is a starch obtained from the pith and cortex of the stem of Cycas revolute and Cycas rumphi.

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Botany lecture notes

Anomalous Secondary Thickening in Dracaena Stem: Lecture Notes and Diagram

anomalous secondary thickening in monocots

Anomalous Secondary Thickening in Dracaena
Anomalous Secondary Thickening in Monocots

Before going to the secondary thickening in Dracaena, first see what anomalous secondary thickening is and how the process of anomalous secondary thickening happens in plants.

What is Anomalous Secondary Thickening?

Ø  In many plants, the pattern of the secondary thickening shows deviation from the normal type.

Ø  The term “Anomalous Secondary Growth” is given for this deviation or variation.

Ø  The anomalous secondary growth is more common in tropical plants.

Ø  Anomalous secondary thickening is NOT an anomaly or disease in plants; rather it is an adaptation to suit the habit and habitat of the plant.

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characteristics of glossopteridales

Glossopteridales-General Characteristics (Glossopteris Short Notes)

What is Glossopteris

Glossopteridales General Characteristics
Characteristics of Glossopteridales: Fossil Gymnosperm


Ø  Glossopteridales included an extinct group of seed plants (Gymnosperms).

Ø  They were originated during the Permian period on the Gondwana Continent.

Ø  They became the dominant vegetation in the Permian period.

characteristics of glossopteridales

Ø  They extinct completely by the end of the Triassic period.

Ø  The order name derived from the genus Glossopteris

Ø  Glossopteris is the best-known member of Glossopteridales

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pathogenesis citrus canker

Citrus Canker: Symptoms, Causal Organism and Control Measures – Pathology Lecture Notes

citrus canker causal organism

Citrus Canker
(Symptoms, Causal Organism, Etiology and Control Measures)


Citrus is the common term for the fruits of the genus Citrus of family Rutaceae. They are native to Australia and now cultivated all over the world in cooler climates. Common examples of fruits from Citrus are oranges, lemons, grapefruits, limes etc.

Citrus Canker

Ø  Citrus canker is a bacterial disease.

Ø  It is wide-spread in all the citrus growing areas.

Ø  It is one of the serious disease affecting citrus plants in India, China and Japan.

Ø   The disease was originated in China and now it causes large-scale destruction in citrus orchards.


canker symptom leaf

Ø  The canker occurs on leaves, twigs, branches and fruits.

Ø  The lesions first appear on leaves.

Ø  The spots first develop on the lower surface of the leaf.

Ø  In the beginning; the lesions will be small, round and watery.

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loss of rice due blast disease

Blast Disease of Paddy: Symptoms, Causal Organism and Control Measures

blast of rice

Blast Disease of Paddy
(Symptoms, Casual Organism, Etiology and Control Measures)

loss of rice due blast diseasePaddy/rice

Rice is a cereal grain. It is the seeds of Oryza sativa (Asian rice) or Oryza glaberrima (African rice). Rice is the most extensively consumed staple food of human. It is the major staple food in Asia. Rice is the third highest agricultural commodity in worldwide production. The un-milled rice is known as “paddy“.

Blast Disease of Paddy

Ø  Blast disease is one of the most severe diseases affecting paddy.

Ø  It is a fungal disease prevalent all over the world.

Ø  It is a major problem in rice production in countries like Japan, India, Taiwan and the USA.

Ø  Blast disease is more severe in areas with high humidity and rainfall.

Ø  Losses due to the disease may be up to 90% of the total corp.

Ø  In India, the blast disease is more common in Southern parts, particularly coastal areas.

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