This document discusses seed aging and its causes. Seed aging is a natural process that occurs over time due to genetic, environmental, and storage-related factors. The main causes of seed aging are genetic traits that increase susceptibility, exposure to high temperatures/humidity and fluctuating moisture levels, oxidative stress from respiration that produces reactive oxygen species, improper moisture content during storage, harvesting seeds before maturity, and pest/pathogen infestation. Proper storage conditions like cool, dry, and dark storage in airtight containers can help slow the aging process and maximize seed viability and longevity.

2. NAME : YASIR AHMAD
C.NO : 64
SEMESTER : 2ND
DEPARTMENT : AGRONOMY
ASSIGMENT NO : 07
DEGREE : M.Sc (AGRONOMY)
SUBMITTED TO : PROF. DR. INAMULLAH

3. Seed ageing
• Seed ageing, also known as
seed deterioration, is the loss of
seed quality or viability over
time. It is a natural process that
occurs in all seeds, but the rate of
ageing can be slowed by
proper storage conditions.

4. Causes of seed ageing
Seed aging is a natural process that
occurs due to various factors,
including genetic factors,
environmental factors, oxidative
stress, moisture content, seed
maturity, pest and pathogen
infestation, and seed storage
conditions. The specific causes and
rates of seed aging can vary
depending on the plant species.
Different seeds have different
inherent lifespans, and their
susceptibility to aging can differ.

5. 1. Genetic factors:
• Some plant species have
inherently shorter seed longevity
due to their genetic makeup.
Certain genetic traits can make
seeds more prone to aging and
deterioration. For example, seeds
with a high content of fatty acids
are more susceptible to
oxidation, which can lead to seed
deterioration.

6. 2. Environmental factors
• The conditions in which seeds
are stored greatly influence their
aging process. The main
environmental factors that
contribute to seed aging include
temperature, humidity, light
exposure, and oxygen levels.
Exposure to high temperatures,
high humidity, and fluctuating
moisture levels can accelerate
seed aging.

7. 3. Oxidative stress
• Oxygen plays a crucial role in
seed aging. During storage, seeds
continue to respire and undergo
metabolic processes, producing
reactive oxygen species (ROS).
These ROS can cause damage to
cellular components, including
DNA, proteins, and lipids,
leading to seed deterioration.
ROS can also be generated by
exposure to environmental
factors such as heat, light, and
radiation.

8. 4. Moisture Content
• Seeds need a specific moisture
content for optimal storage. If
seeds are stored with high moisture
content, they can be prone to fungal
and bacterial growth, which can
damage the seeds and reduce their
viability. Conversely, extremely dry
conditions can also lead to seed
aging and loss of viability.

9. 5. Seed Maturity
• Seeds that are harvested
prematurely may have reduced
viability and a shorter lifespan.
Seeds should be harvested at the
proper stage of maturity to
ensure maximum longevity.

10. 6. Pest and
Pathogen Infestation
• Seeds that are infested by pests or
pathogens are more likely to age
quickly. Insects, mites, fungi, and
bacteria can attack seeds, causing
physical damage or introducing
diseases that accelerate seed
deterioration.
Figure 1. Conventional methods of
detection of fungal pathogens in seeds: (a)
wheat seeds infected with Fusarium under
agar media test; (b) germinating seeds
of Lathyrus sativus under blotter testing
method after 40 years of storage at the CRF-
INIA gene bank; (c) morphology of
conidiophores and typical conidia
of Botrytis spp.; (d) Aspergillus spp. by
optical microscope.

11. 7. Seed Storage Conditions
• Proper storage conditions are
critical for maintaining seed
viability. Seeds should be stored
in cool, dry, and dark
environments, preferably in
airtight containers to minimize
exposure to oxygen and
moisture. Inadequate storage
conditions can lead to
accelerated seed aging.

12. Methods of managing of seed ageing
• There are a number of methods that can be used to manage seed ageing. Some
of these methods include:
• Cool storage: Storing seeds at cool temperatures can help to slow down the
metabolic activity of the seed. This can help to extend the seed's lifespan. The
ideal storage temperature for seeds is between 35 and 40 degrees Fahrenheit.
• Dry storage: Storing seeds in dry conditions can help to prevent the seeds
from becoming moldy or contaminated with pests. The ideal humidity level for
seed storage is between 30 and 40%.
• Dark storage: Storing seeds in dark conditions can help to prevent the seeds
from being damaged by light. Light can damage the seed's DNA and proteins,
which can lead to seed ageing and death.

13. continue
• Airtight storage: Storing seeds in airtight containers can help to prevent the
seeds from becoming contaminated with moisture or pests.
• Rotation of seed stock: Rotating your seed stock means that you will always
be using seeds that are fresh and viable. This can help to prevent you from
using seeds that have aged prematurely.
• Testing of seed stock: Testing your seed stock regularly can help you to
determine the viability of your seeds and to identify any potential problems.
• By following these methods, you can help to ensure that your seeds will last for
many years.