Plant propagation is the reproduction of new plants from seeds and vegetative parts of the plant such as leaves, stems, and roots.
The two major methods of plant propagation are :-
• Sexual and
• Asexual propagation.
I’m Tapsendra Patel and in this article, we will focus on Propagation of Seeds and there methods, Seeds classes and Types of dormancy
The reproduction of plants by seeds is Sexual propagation.
Asexual reproduction produces a plant that is genetically identical to its parent.
In addition to their expense, some advantages of seeds include :-
• Seeds have a convenient method for storage.
• They remain viable if they are kept cool and dry and
• They are an easy method for starting disease-free plants.
But in some cases, seeds may not be the most practical since it can take a long time for plants to reach maturity. This is true for many fruit trees.
A variety of factors must be considered for the production and certification of seed.
To produce high-quality seed, it is important to choose the proper location i.e
Typically an arid climate is best because there are fewer disease problems ➡️ After a suitable location is selected➡️ you must know when seeds are ripe to maximize germination rates and produce high-quality seedlings ➡️ After the seeds are harvested they should be sieved to remove debris ➡️ cleaned ➡️ properly stored to maintain their quality high.
Plant breeders select plants with desirable characteristics such as :-
• High yield
• Disease resistance, and
• A variety of other traits.
(1) Nuclear seeds - have no labelled color and produced by original breeders in laboratories and are 100% physical and genetically pure.
(2) Breeder seed - small amount of seed with desirable traits produced by the breeder. Labelled by Yellow color.
(3) Foundation seed - produced under the supervision of agricultural research stations to assure genetic purity and identity.
(4) Registered seed - seed is given to a certified grower for the production.
(5) Certified seed - the progeny of registered seed.
After certified seed has been produced, many federal and State Laws regulate its packaging and distribution.
The law requires that the following information be present on the seed packet :-
• Trueness of name
• Origin
• Germination percentage
• Pure seed percentage
• Percentage of other crop seed and/or weed seed
• Percentage of other ingredients.
After seeds are stored for any length of time, the germination rate should be tested because this rate decreases with time.
Germination Percent is the percentage of seeds that will sprout and grow (90 seeds germinate out of 100 seeds = 90% germination).
-> If you need 100 plants, you must sow more than 100 seeds. By sowing 100 seeds and determining the number of seeds that germinate out of 100 , can easily test the percentage of seed germination <- .
This is often done on a moist paper towel. Unfortunately, if it doesn’t germinate, it doesn’t necessarily mean that it is nonviable because it could be dormant.
• Direct Seeding
• Indirect seeding.
Some examples of crops that can be seeded directly are :-
• Corn
• Pea
• Lettuce and
• Beans.
Small seeds can be pelletized to increase the size to facilitate planting.
Another method called Fluid Drilling in which we uses pre-germinated seed suspended in a protective gel. The gel prevents seeding injury to the emerging radicle (baby root) and maintains seed moisture.
For direct seeding to be successful, a proper site must be selected ➡️ The site must be disease-free and have adequate environmental conditions ➡️ After the site is selected we must properly prepare the seedbed by removing any large objects and create proper soil texture for optimal moisture retention and aeration ➡️ We must know that the optimum rate for planting ➡️ use the correct planting depth and spacing ➡️ make sure seeds receive optimal moisture during the germination process.
Some examples of plants that are commonly indirectly seeded are :-
• Tomato
• Pepper
• Cucumber and
• Onion.
Some of the advantages of indirect seeding are :- good establishment and less time to maturity which reduces the actual field-growing period.
The disadvantages include :-
• Higher cost since seedlings are produced indoors and it is not as easy to plant mechanically and difficult to handle due to bulky vegetative growth.
• Transplanting shock is a major problem with indirect seeding when seedlings are not properly prepared for transplanting and improper planting techniques are used.
High-quality transplants start with high-quality seeds. After high-quality seeds have been procured, they need a good germination medium that has :-
• Proper drainage and aeration
• Adequate water and nutrient holding capacity
• Favorable pH
• Proper essential elements
• Free from insects, weeds, and disease organisms.
After a high-quality germination medium has been selected, the proper environmental conditions must be provided to ensure good germination and subsequent seedling growth. The seedlings must be protected from damping-off, which is a fungal disease that causes the stems to rot at the soil line. The most effective way to control this disease is to use proper sanitation practices and avoid warm, wet mediums.
Fungicides can be used to control damping-off when cultural practices are not sufficient to control then. Before transplanting them to the field, seedlings should be checked to ensure success under the harsh outdoor environment. Transplants can be checked by gradually uncountering seedlings to cooler temperatures with less frequent watering.
For seed germination to occur the seed must be :-
• Viable
• Must be subjected to the proper environmental conditions
• Must overcome primary dormancy.
(1) Physical dormancy or seed coat dormancy - occurs when the seed covering is impervious to water. Germination can be artificially induced by scarification( process of breaking the seed coat ). This can be accomplished artificially either by soaking the seed in dilute acid for a some period of time.
In nature, this type of dormancy can be overcome by :-
microorganisms breaking down the seed coat by the seed passing through the digestive tracks of birds and animals
by mechanical abrasion like by freezing/thawing, and in some species also by fire.
(2) Mechanical dormancy or hard seed dormancy - it is caused by the seed-enclosing structure being too strong to permit expansion of the embryo even though water can’t penetrate it. Germination can be induced artificially by physically cracking the hard seed coat.
In nature, the seed coat can be broken down by microorganisms and/or through the process of freezing and thawing.
(3) Chemical dormancy or inhibitor dormancy - it is caused by germination inhibitors, which accumulate in the fruit or seed coverings during development. This type of dormancy can be overcome artificially by leaching the seed coat, removing the seed coat, or both.
In nature, chemical dormancy is typically overcome by leaching the seed coat.
(4) Morphological dormancy - occurs when seeds are detached from there parent plant when their embryos are not fully developed. This type of dormancy can be overcomed by treating the seeds with gibberellic acid, a plant hormone used to promote seed germination.
In nature, very few seeds will germinate if they are shed from the plant before becoming fully developed.
(5) Physiological dormancy - it is a general type of dormancy in freshly harvested seeds from herbaceous plants. It is caused by environmental effects such as temperature and light which lead to an increase in internal growth inhibitors, spread throughout the seed, and cannot be overcome by removing the seed coat or by leaching. It can be overcome artificially by stratification, which places seeds on a moist medium at warm temperatures or at cold temperatures.
The seeds may also be treated with gibberellic acid.
In nature, physiological dormancy is overcome by environmental conditions similar to artificially induced stratification.
In conclusion, sexual propagation is the major means of propagation in nature and agriculture today because it is easy and relatively inexpensive. So in this article we have discussed :-
• Important factors involved in the stages of seed production.
• Direct and Indirect seeding
• Types of dormancy.
- TAPSENDRA PATEL
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The two major methods of plant propagation are :-
• Sexual and
• Asexual propagation.
I’m Tapsendra Patel and in this article, we will focus on Propagation of Seeds and there methods, Seeds classes and Types of dormancy
The reproduction of plants by seeds is Sexual propagation.
Asexual reproduction produces a plant that is genetically identical to its parent.
Sexual propagation
Being easy and relatively inexpensive Sexual propagation is major means of reproduction . In a variety of cases, seeds are homozygous and produce seeds that are true to type, in other words, the same as the parent plant. This is the most common means of propagation for self-pollinating plants.In addition to their expense, some advantages of seeds include :-
• Seeds have a convenient method for storage.
• They remain viable if they are kept cool and dry and
• They are an easy method for starting disease-free plants.
But in some cases, seeds may not be the most practical since it can take a long time for plants to reach maturity. This is true for many fruit trees.
A variety of factors must be considered for the production and certification of seed.
To produce high-quality seed, it is important to choose the proper location i.e
Typically an arid climate is best because there are fewer disease problems ➡️ After a suitable location is selected➡️ you must know when seeds are ripe to maximize germination rates and produce high-quality seedlings ➡️ After the seeds are harvested they should be sieved to remove debris ➡️ cleaned ➡️ properly stored to maintain their quality high.
Plant breeders select plants with desirable characteristics such as :-
• High yield
• Disease resistance, and
• A variety of other traits.
Seed Classes
Prior to commercial distribution of a new cultivar that a breeder has produced, 4 classes/stages of seed production must occur :-(1) Nuclear seeds - have no labelled color and produced by original breeders in laboratories and are 100% physical and genetically pure.
(2) Breeder seed - small amount of seed with desirable traits produced by the breeder. Labelled by Yellow color.
(3) Foundation seed - produced under the supervision of agricultural research stations to assure genetic purity and identity.
(4) Registered seed - seed is given to a certified grower for the production.
(5) Certified seed - the progeny of registered seed.
After certified seed has been produced, many federal and State Laws regulate its packaging and distribution.
The law requires that the following information be present on the seed packet :-
• Trueness of name
• Origin
• Germination percentage
• Pure seed percentage
• Percentage of other crop seed and/or weed seed
• Percentage of other ingredients.
After seeds are stored for any length of time, the germination rate should be tested because this rate decreases with time.
Germination Percent
Germination Percent is the percentage of seeds that will sprout and grow (90 seeds germinate out of 100 seeds = 90% germination).
-> If you need 100 plants, you must sow more than 100 seeds. By sowing 100 seeds and determining the number of seeds that germinate out of 100 , can easily test the percentage of seed germination <- .
This is often done on a moist paper towel. Unfortunately, if it doesn’t germinate, it doesn’t necessarily mean that it is nonviable because it could be dormant.
Seeding Methods
Seeds can be planted by :-• Direct Seeding
• Indirect seeding.
Direct seeding
Direct seeding involves planting seeds directly in the soil outdoors.Some examples of crops that can be seeded directly are :-
• Corn
• Pea
• Lettuce and
• Beans.
Small seeds can be pelletized to increase the size to facilitate planting.
Another method called Fluid Drilling in which we uses pre-germinated seed suspended in a protective gel. The gel prevents seeding injury to the emerging radicle (baby root) and maintains seed moisture.
For direct seeding to be successful, a proper site must be selected ➡️ The site must be disease-free and have adequate environmental conditions ➡️ After the site is selected we must properly prepare the seedbed by removing any large objects and create proper soil texture for optimal moisture retention and aeration ➡️ We must know that the optimum rate for planting ➡️ use the correct planting depth and spacing ➡️ make sure seeds receive optimal moisture during the germination process.
Indirect seeding
Indirect seeding involves planting seeds indoor growing seedlings prior to transplanting to a larger container or to a location outdoors.Some examples of plants that are commonly indirectly seeded are :-
• Tomato
• Pepper
• Cucumber and
• Onion.
Some of the advantages of indirect seeding are :- good establishment and less time to maturity which reduces the actual field-growing period.
The disadvantages include :-
• Higher cost since seedlings are produced indoors and it is not as easy to plant mechanically and difficult to handle due to bulky vegetative growth.
• Transplanting shock is a major problem with indirect seeding when seedlings are not properly prepared for transplanting and improper planting techniques are used.
High-quality transplants start with high-quality seeds. After high-quality seeds have been procured, they need a good germination medium that has :-
• Proper drainage and aeration
• Adequate water and nutrient holding capacity
• Favorable pH
• Proper essential elements
• Free from insects, weeds, and disease organisms.
After a high-quality germination medium has been selected, the proper environmental conditions must be provided to ensure good germination and subsequent seedling growth. The seedlings must be protected from damping-off, which is a fungal disease that causes the stems to rot at the soil line. The most effective way to control this disease is to use proper sanitation practices and avoid warm, wet mediums.
Fungicides can be used to control damping-off when cultural practices are not sufficient to control then. Before transplanting them to the field, seedlings should be checked to ensure success under the harsh outdoor environment. Transplants can be checked by gradually uncountering seedlings to cooler temperatures with less frequent watering.
For seed germination to occur the seed must be :-
• Viable
• Must be subjected to the proper environmental conditions
• Must overcome primary dormancy.
Dormancy
There are five categories of primary seed dormancy :-(1) Physical dormancy or seed coat dormancy - occurs when the seed covering is impervious to water. Germination can be artificially induced by scarification( process of breaking the seed coat ). This can be accomplished artificially either by soaking the seed in dilute acid for a some period of time.
In nature, this type of dormancy can be overcome by :-
microorganisms breaking down the seed coat by the seed passing through the digestive tracks of birds and animals
by mechanical abrasion like by freezing/thawing, and in some species also by fire.
(2) Mechanical dormancy or hard seed dormancy - it is caused by the seed-enclosing structure being too strong to permit expansion of the embryo even though water can’t penetrate it. Germination can be induced artificially by physically cracking the hard seed coat.
In nature, the seed coat can be broken down by microorganisms and/or through the process of freezing and thawing.
(3) Chemical dormancy or inhibitor dormancy - it is caused by germination inhibitors, which accumulate in the fruit or seed coverings during development. This type of dormancy can be overcome artificially by leaching the seed coat, removing the seed coat, or both.
In nature, chemical dormancy is typically overcome by leaching the seed coat.
(4) Morphological dormancy - occurs when seeds are detached from there parent plant when their embryos are not fully developed. This type of dormancy can be overcomed by treating the seeds with gibberellic acid, a plant hormone used to promote seed germination.
In nature, very few seeds will germinate if they are shed from the plant before becoming fully developed.
(5) Physiological dormancy - it is a general type of dormancy in freshly harvested seeds from herbaceous plants. It is caused by environmental effects such as temperature and light which lead to an increase in internal growth inhibitors, spread throughout the seed, and cannot be overcome by removing the seed coat or by leaching. It can be overcome artificially by stratification, which places seeds on a moist medium at warm temperatures or at cold temperatures.
The seeds may also be treated with gibberellic acid.
In nature, physiological dormancy is overcome by environmental conditions similar to artificially induced stratification.
In conclusion, sexual propagation is the major means of propagation in nature and agriculture today because it is easy and relatively inexpensive. So in this article we have discussed :-
• Important factors involved in the stages of seed production.
• Direct and Indirect seeding
• Types of dormancy.
- TAPSENDRA PATEL
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