The classical tests are widely reviewed and problems inherent to their application are discussed. Related vigour indices, mostly assessed in a destructive manner, are generally used to establish correlations with declining seed viability. The course of development of seed quality testing techniques is associated with that of basic knowledge and insight into seed morphology, physiology, biochemistry and molecular biology. First the definition of seed germination, viability, and vigour derived from evaluation methods over the last four decades will be reassessed to account how new techniques need to satisfy the demand of farmers, seed industries, seed-gene banks and basic seed research. This paper reviews the developments of techniques which are applied in seed quality, in terms of germination and vigour testing. These results offer perspectives for the selection of favourable alleles to improve certain vigour traits in wheat, although the negative effects of the same chromosome regions on other traits may limit their practical use. A candidate homologues search suggested the putative functions of the genes within the respective regions. QTL for seedling growth were identified on chromosomes 4D and 5D. QTL for seed longevity were coincident with those for germination or seed vigour on chromosomes 1D or 5D. Seed vigour-related QTL were present in a region of chromosome 5DL linked to Xgwm960. A region on chromosome 7DS associated with Xgwm1002 harboured loci controlling the development of normal seedlings. Most of the QTL for germination sensu stricto clustered on chromosome 1DS in the region Xgwm1291–Xgwm337. Twenty QTL were mapped to chromosomes 1D, 2D, 4D, 5D, and 7D. Seedling growth was assessed both under non-stressed and under osmotic stress conditions. Seed longevity was evaluated from the relative trait values. To quantify seed vigour, the same traits were measured from batches of seed exposed for 72 h at 43☌ and high (ca. Seed germination (capacity, timing, rate and synchronicity) was characterized by a standard germination test, based either on the 1 mm root protrusion (germination sensu stricto) or the development of normal seedlings. Quantitative trait loci (QTL) controlling germination, seed vigour and longevity, and early seedling growth were identified using a set of common wheat lines carrying known D genome introgression segments.
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