How to discover the seed quality

                                                                                   

    

In simple terms, seed Quality means suitability of seeds for sowing and establishing a sufficiently performing crop field. It is comprised of ten attributes of un-equal importance. The importance varies depending on prevailing circumstances.

• Analytical purity, Is the percentage weight of seed sample that is in fact seed of the species named on the label after laboratory analysis, how much of it is a seed. It is weighed after separation of all impurities, impurities are seeds of other crop species, weed seeds and inert matter such as broken seeds, chaff, pieces of leaves, soil particles. Seed purity mainly depends on the success of the cleaning operation after harvest.                                                                                                                                                                                                                            Percentage of 97 or more is expected in most crop species but may be lower in some grasses because of empty florets which are difficult to remove.                                                                                                                                                                                                 
• Species purity, it is the number of seeds of species other than the one indicated in the label for the weight submitted for analysis: example 2/kg.                                                                                                                                                                                  
• Free from the weed seed, The number of weed seeds per weight of sample examined. Condemnable weeds are those which once established are difficult to eradicate. They are referred to as noxious weeds. Expressed in numbers because weed seeds may be so much different in size from the crop seed that percentage by weight may be of no real significance. What is important is not weight but the number of weed seeds that are sown with the crop.                                                                                                                                                                                       
• Cultivar purity, Measures the seed's genetic quality as developed by the breeder, freedom from seeds of other cultivars of the same species. Cultivars are more certainly identified by examination of growing plants, during DUS (distinctiveness, uniformity, and stability) test.                                                                              
• Germination capacity, it is the percentage by numbers of pure seeds which produce normal seedlings in a  laboratory test. It indicates the potential of a seed lot for establishing good field conditions. It is influenced by harvesting and subsequent storage conditions and by the dormancy status of the seed.                                                                                                                                                                                                                                                                    Germination capacity can be combined with analytical purity and expressed as one value. The value is known as PURE LIVE SEED. The pure live seed is equal to analytical purity percentage times germination capacity divide by one hundred. Pure live seed indicates how much percentage by weight of the seed lot consists of seeds of the named species which are capable of germinating and produce robust seedlings.                                                                                          
• Vigor, Is the ability good seedlings even under poor conditions. It is usually associated with high germination capacity but seeds of high germination may have a low percentage of vigorous seeds. Vigor can be influenced by damage embryo incurred during harvesting or subsequent processing.                                                        

1. Stage of maturity at harvest
2. Seed size
3. Storage conditions, for example, humidity and presence of pathogens
4. Genetic factors, for example, hybrid cultivars.                                                                                          

• Seed size, Large seed size is an indicator of vigor. The bigger the seed, the large the size of the seedling and leaf area for photosynthesis. Larger seeds have greater potential to emerge if deeply buried. Small, shriveled seeds have no practical planting value. Seed size is usually expressed as a weight of a hundred or hundred seed. Uniformity of seed size influences.

1. The effectiveness  of seed cleaning operations
2. Uniformity of growth of the seedling
3. Effectiveness of mechanical drilling during planting.

• Uniformity, It is nearness to identical characteristics when samples are drawn from different points in the same lot, seed size, color, shape. It may vary due to poor grading and mixtures.                         
• Seed health, Presence or absence of the seed-borne pathogen in the seed, which are seed-borne fungi, bacteria, and viruses. It is best checked by harvesting seeds from healthy plants only. This is archived by imposing certification standards of seed health either based on the incidence  of diseases in the crop or on laboratory tests of seeds to be certified.                                                       
• Moisture content, in the prevention of water per unit weight of seed on a wet or dry basis. The moistures contents of seeds are very important especially for the effective storage of seed