Vigour tests
Standard germination test is an indicator of seed quality, which can be used
to predict the field emergence, if soil conditions are nearly ideal (DUURANT and
GUMMERSON, 1990). However, conditions in which the seed is found during
examination are often in conflict with the conditions in the field. Field germination
depends on seed viability. Seed viability or seed vigour are the set of characteristics
that determine the activity and behaviour of the seed lots of commercially acceptable
seed germination in different environmental conditions. In addition to the above
mentioned, longevity of the seed is determined by the seed vigour without adverse
consequence (ISTA, 2009). To obtain more precise information about the quality of
the seed lot different vigour tests are used (MILOŠEVIĆ and ĆIROVIĆ, 1994).
Testing of seed viability using different seed vigour tests is very significant,
since vigour tests give results, which are often better correlated with the results of
field germination under unfavourable environmental conditions, than the results
obtained by application of standard laboratory germination test (JOHANSEN and WAX,
1978).
The term vigour of viability is used to describe the physiological
characteristics of seeds that control its ability to germinate rapidly in the soil and to
tolerate various, mostly negative environmental factors. Results of vigour tests can
be used in deciding whether the seed lots can be sown earlier in the season, when the
occurrence of stressful conditions is possible, or it should be sown later, when the
soil is warmer and the conditions become more favourable for germination and
seedling growth (MILOŠEVIĆ and ZLOKOLICA, 1996). Due to the complexity of the
term vigour itself ISTA (1976) has defined it as follows: "Vigour is the sum of those
seed properties that determine the level of activity of seeds or seed lots during
germination process“. Vigour seed is for now only a concept, rather than a set of
specific characteristics of seeds or seed lots. The value obtained by determination of
vigour is affected by genetic constitution of seed, the external conditions in which
the mother plant is grown, and nutrition applied during that period, maturity of seed
at harvest, seed weight and its size, mechanical injuries, aging, pathogens etc. ISTA
has determined in its rules that vigour tests must meet two criteria, which among
other things depend on plant species being tested. The first criterion is repeatability
of the applied method, i.e. sufficient uniformity of the terms under which the test is
run, in order to obtain results, which are approximately equal under these terms. The
second criterion is that the relation between the results of vigour test, and the results
of seedling growth in the field are approximately the same
Vigour tests Standard germination test is an indicator of seed quality, which can be used to predict the field emergence, if soil conditions are nearly ideal (DUURANT and GUMMERSON, 1990). However, conditions in which the seed is found during examination are often in conflict with the conditions in the field. Field germinationdepends on seed viability. Seed viability or seed vigour are the set of characteristics that determine the activity and behaviour of the seed lots of commercially acceptable seed germination in different environmental conditions. In addition to the above mentioned, longevity of the seed is determined by the seed vigour without adverse consequence (ISTA, 2009). To obtain more precise information about the quality of the seed lot different vigour tests are used (MILOŠEVIĆ and ĆIROVIĆ, 1994). Testing of seed viability using different seed vigour tests is very significant, since vigour tests give results, which are often better correlated with the results of field germination under unfavourable environmental conditions, than the results obtained by application of standard laboratory germination test (JOHANSEN and WAX, 1978). The term vigour of viability is used to describe the physiological characteristics of seeds that control its ability to germinate rapidly in the soil and to tolerate various, mostly negative environmental factors. Results of vigour tests can be used in deciding whether the seed lots can be sown earlier in the season, when the occurrence of stressful conditions is possible, or it should be sown later, when the soil is warmer and the conditions become more favourable for germination and seedling growth (MILOŠEVIĆ and ZLOKOLICA, 1996). Due to the complexity of the term vigour itself ISTA (1976) has defined it as follows: "Vigour is the sum of those seed properties that determine the level of activity of seeds or seed lots during germination process“. Vigour seed is for now only a concept, rather than a set of specific characteristics of seeds or seed lots. The value obtained by determination of vigour is affected by genetic constitution of seed, the external conditions in which the mother plant is grown, and nutrition applied during that period, maturity of seed at harvest, seed weight and its size, mechanical injuries, aging, pathogens etc. ISTA has determined in its rules that vigour tests must meet two criteria, which among other things depend on plant species being tested. The first criterion is repeatability of the applied method, i.e. sufficient uniformity of the terms under which the test is run, in order to obtain results, which are approximately equal under these terms. The second criterion is that the relation between the results of vigour test, and the results of seedling growth in the field are approximately the same
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