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With aim to improve characterization and eventually, utilisation of garlic collection from the Institute of Field and Vegetable Crops in Serbia, the genetic diversity of 52 accessions was estimated based on microsatellite markers, agronomic, biochemical and phenotypic traits (UPOV descriptor). The Shannon index H′ with a value of 0.47–0.95 indicated a high level of diversity for the greatest number of examined traits according to the UPOV descriptor. Based on agronomic and biochemical traits, groups of genotypes with the highest potential for yield and bioactive properties improvement were singled out. Molecular evaluation indicated the presence of duplicates in the collection and necessity of further research with additional number of DNA markers. The obtained results are important from the aspects of breeding and development of new varieties with improved yield and functional value as well as more economical conservation of genetic resources. Since diversity of plant genetic resources constantly decreases, the obtained results have long-term significance because preserved and genetically variable collections represent a valuable source of desirable genes for future human needs. [ABSTRACT FROM AUTHOR]

The research describes the field comparison of 90 inbred lines of castor plant derived from both selected and wild germplasm. It was carried out in central-western Italy. An important aim of this work was to describe each inbred line based on 19 morphological traits concerning stem, leaves, racemes and capsules and then to suggest a list of descriptors to International Union for the Protection of New Varieties of Plants as to conduct the Distinctness, Uniformity and Stability test also on the castor plant. The plants in the field were grown at wide distances to avoid competition and enable observation of the growth habit, particularly the specific capacity of branching. An additional characterization of the inbred lines was obtained measuring 7 quantitative traits related to main stem and first raceme; the number of racemes per plant was used to quantify the plant branching. The results allowed distinguishing almost all the genotypes using only the morphological traits. Nectaries at the node, emergences on the stem and petioles, colour of nectaries on petiole resulted important plant descriptors. The two pairs of inbred lines (Tor87#9 vs. Tor87#83 and Pod87#255Hy2 vs. Rot95#55-23) were distinguished thanks to the quantitative traits. Based on the morphological traits, two UPGMA dendrograms, one for the dwarf and one for the normal genotypes, were characterized and the resulting clusters better explained the relationships among the various inbred lines. Six genotypes (Pod87#389, Tor87#81A, Tor87#220B, Tor87#287, Tor87#287Hy, and Liba21) resulted unable to flower in the field; in these inbred lines the induction to flower is particularly influenced by the environmental growth conditions. Regarding the branching ability, the strong apical dominance of two inbred lines (Pod94#31-2 and Pod93#211) obtained from previous breeding programs was confirmed and it was possible to detect other interesting genotypes (Pod87#287A, Pod87#287B, Tor86#67). The several inbred lines described herein showed a wide range of phenotypes that might be useful in various fields of research. [ABSTRACT FROM AUTHOR]

Solidity of microsatellite markers is a key issue for varietal identification, especially when they are used for legal purposes, what includes their probable future use in the distinctness, uniformity and stability testing of new varieties needed for the granting of Plant Breeders' Rights. Nine grapevine microsatellites (VVS2, VVMD5, VVMD27, VVMD28, ssrVrZAG29, ssrVrZAG62, ssrVrZAG67, ssrVrZAG83 and ssrVrZAG112), which had previously demonstrated its capacity to discriminate any grapevine variety, have been assessed to evaluate its uniformity and stability. 19 varieties were selected, representative of a high diversity for morphological, agronomical, cultural and historical aspects, as well as for microsatellite allele variability. Then, for each variety, uniformity and stability were evaluated through the analysis of 50 plants from each of three different plots, and five plants from each of seven additional plots. Material from 4,137 plants of 229 plots of the 19 varieties was sampled in seven countries. Of 3,654 plants analyzed with the set of nine microsatellites, 3,299 were of the right variety and used for the survey. An average of 172 individual values was studied for each allele of each microsatellite of each variety, and none differences were detected that could not be explained as technical variations, with the exception of several putative chimeras in two varieties. Of the total of 171 variety x microsatellite combinations, only in one combination ('Merlot' x VVMD27) the number of off-types exceeded the threshold allowed. The remaining 170 combinations have been found uniform and stable according to internationally accepted rules. [ABSTRACT FROM AUTHOR]

The need for precise characterisation of crop materials has assumed importance in any established sui generis system for effective protection of plant varieties. Considering this requirement, 37 Indian maize inbreds were analysed for allozyme variations. Seven enzyme systems comprising 16 isozyme loci were analysed using starch gel electrophoresis. The allelic variants were designated using the well-characterised maize inbred Mo 17 as a standard. A total of 29 alleles were scored at the 16-isozyme loci studied. Malate dehydrogenase (Mdh), acid phosphatase (Acp), phosphoglucoisomerase (Pgi), 6-phosphogluconate dehydrogenase (Pad) and isocitrate dehydrogenase (Idh) were the most informative isozyme systems for characterisation of the maize inbreds. These enzyme systems were also useful in detecting and quantifying the extent of `off-types' in each seed lot analysed. The percent off-types (inclusive of the admixtures and segregates) were as high as 47 to 50 percent in seed lots of a few of the inbreds. The results of the study were also useful in studying genetic diversity among the inbreds. An UPGMA based cluster analysis of the allozyme data revealed presence of only moderate genetic diversity among the Indian maize inbreds. This is of significance in crop yield stability as these inbreds have been used extensively in the production of F1 hybrids occupying large area under maize cultivation in India. [ABSTRACT FROM AUTHOR]