• Seed vigour is a sum of those properties that determine the activity and level of performance of
seeds lots of acceptable germination in a wide range of environment
• Rate and uniformity of seed germination and seedling growth.
6. 1. Genotype
• Some type of seeds are inheriently long lived , others are short lives while other have an
intermediate life span owing to their difference on genetic makeup
7. 2.Seed size
• The smallest seed in the world – mustard seed .
• It play an important role in controlling vigous as found in jute , wheat and etc
• The influence of seed size and seed vigous has also been variously determine in cereal , cotton ,
vegetable, sugar beet and a no of forage crops.
• Seeds are mainly of 3 types
1. small size seed
2. Medium size seed
3. Large size seeds
11. 1. Mechanical injury at harvesting
• Mechanical damage ids one of the major causes of seed deterioration during storage . Very
dry seeds are prone to mechanical damage and injuries .
• Such damages may result in physical damage or fracturing of essential seed parts , broken seed
coats permits early entry and easy access for microflora, make the seed vunerable to fungal
12. 2.pre- harvesting
• If the climate during seed setting is adverse or the seed producing plants have suffered from
macro and or micro nutrient deficiency .
• Heathy seed produced by heathy plant have more vigous than those suffering from disease and
insect pest attack
13. 3.Soil temperature and moisture
• Seeds stored at high moisture content demonstrate increase respiration ,heating and fungal
invasion resulting in reduced and viability .
• After physiological maturity ,the rate of seed quality losses depend upon the degree of
unfavorable environment condition surround the seed
• Storing seeds at high moisture content enhance the risk of quicker deterioration at shorter time
• The lower the moisture content, the longer seeds can be stored provided that the misture level
can be controlled all through the storage period .
14. 4.Effect of tillage and fertilizers
• Tillage is defined as the mechanical manipulation of the soil for the purpose of crop production
affecting significantly the soil characteristics such as soil water conservation, soil temperature,
infiltration and evapotranspiration processes.
• Adequate N,P,K level and proper tillage operation have influenced the seed yield and
seed vigour in wheat