SUMMARYKnowledge of genetic diversity of confectionary sunflower can have a large impact on its use in breeding programmes. However, levels and distribution of genetic variation within the confectionary sunflower gene pool are still not adequately explored. The aim of the present paper was to describe the diversity of 68 confectionary sunflower genotypes: open-pollinated varieties, lines and hybrids. A total of 32 morphological traits were used for characterization. The Shannon & Weaver diversity index (H) was estimated as a measure of morphological diversity. The mean value of the Shannon index was 0·71, which indicates a high morphological diversity. The lowest diversity was found for leaf descriptors, moderately high to high for seed traits, while the highest values were found for disc flowers and ray florets. The highest individual descriptor diversity was found for: head attitude, the angle of leaf lateral nerves and ray floret disposition. The homogeneity analysis (HOMALS) multivariate reduction technique for nominal categorical data proved to be an efficient method for a comprehensive overview of genotype diversity and group homogeneity. Besides diversity, the number of categories and uniformity of genotype distribution determines discriminative power of descriptors. Traits that contributed the most to the distinction of genotypes were identified, enabling differentiation of genotypes with similar phenotypic attributes. The highest discriminative power was observed in traits such as anthocyanin colouration of stigma (DFIA), seed colour of stripes and seed main colour. The genotypes tested formed two distinctive major groups of varieties and hybrids with inbred lines widely dispersed along both axes. A separate grouping was obtained per the most discriminative traits based on HOMALS analysis, while the best separation was obtained using DFIA. Isolated genotypes that may not be representative by yield or seed-specific traits can be useful sources of traits for breeding. Morphological characterization can be used to improve description and classification of confectionary sunflower germplasm when evaluating diversity.

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Modern breeding of sunflower (Helianthus annuus L.), which started 100 years ago, increased the number and the diversity of cultivated forms. In addition, for more than 50 years, wild sunflower and other Helianthus species have been collected in North America where they all originated. Collections of both cultivated and wild forms are maintained in gene banks in many countries where sunflower is an important crop, with some specificity according to the availability of germplasm and to local research and breeding programmes. Cultivated material includes land races, open pollinated varieties, synthetics and inbred lines. The majority of wild accessions are ecotypes of wild Helianthus annuus, but also 52 other species of Helianthus and a few related genera. The activities of three gene banks, in USA, France and Serbia, are described in detail, supplemented by data from seven other countries. Past and future uses of the genetic resources for environmental adaptation and breeding are discussed in relation to genomic and improved phenotypic knowledge of the cultivated and wild accessions available in the gene banks.

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Winter oilseed rape (WOSR) production is dependent on weather conditions, but is also characterized by low nitrogen (N) use efficiency. The objectives of this study were to: (i) evaluate sources of variability for the seed yield and oil content of four rapeseed cultivars under the influence of three sowing dates (SD trial) and five nitrogen dosages (N trial) during four growing seasons; (ii) understand year-related interactions and the effect of climatic variables in different growth stages; and (iii) assess the presence of interactions cultivar by year (C × Y) and treatment by year (T × Y). Six climatic factors were observed, during germination, overwintering, budding, flowering and ripening. The mixed effect split-plot analysis of variance was used, as well as factorial regression models. The C × Y interaction was the most important for the oil content in both trials. The precipitation at budding stage (75.8%), relative air humidity at overwintering (63.3%) and flowering stage (53.0%) accounted for the highest proportion of T × Y interaction for the seed yield, as well as precipitation at flowering (92.0%) and ripening (85.0%) for the oil content. Water availability was the main determinant of the seed yield and/or oil content accompanied with cooler temperatures during the seed development. The study successfully dissected the effect of year-related climatic variables on the agronomical traits in winter rapeseed. Based on this, appropriate agronomic practices can be applied at specific growing stages to ensure a high seed and oil yield.

Several nutritive values for tubers of 114 Jerusalem artichoke (Helianthus tuberosus) populations were evaluated during 2006. The used material is a part of wild sunflower species collection at the Institute of field and vegetable crops and it is situated in Rimski Šancevi, Novi Sad. The samples were analyzed as fresh tubers on 'Venema' automatic laboratory for alpha amino nitrogen, sodium and potassium content. Total sugar content was determined as the brix value on a refractometer. Total nitrogen was determined by the Kjeldahl method on dried samples. Significant variability was found for all analyzed traits. Total nitrogen varied from 0,695 to 2,179% dry weight (mean 1,23%), alpha amino nitrogen content 0,012 to 0,118% fresh weight (m. 0,07%), potassium 0,231 0,452% fresh weight (m. 0,403%) and sodium 0,0003 - 0,0143% fresh weight (m. 0,007%). Total sugar content varied from 13,69 - 22,94% fresh weight (m. 19,14%). Alpha amino nitrogen is an essential nutrient for animals so that it's presence in tubers of Jerusalem artichoke as food is positive. The protein content is similar to the one in potato and as such satisfactory for nutrition. The K/Na ratio is high which is useful, because an increased content of potassium in food can positively affect the reduction of Na/K ratio and lower systolic blood pressure by a significant amount in adults with mild hypertension. Inulin makes up to 80% of the total sugar content in the tubers of Jerusalem artichoke, and as a dietary fiber and a fructose polymer it positively influences digestion and sugar blood levels. The obtained results suggest that selection of cultivars and populations with inappropriate nutritive values is possible. Further research is needed to estimate the share of genetic in total variability and to determine whether the selection for new cultivars is justified

locations in the region of Vojvodina and central Serbia was carried out in order to study GEI (genotype × environment interaction) on oil yield and stability of hybrids using non-parametric measures of stability. The non-parametric test indicated the presence of significant crossover interaction [G(E) and E(G)]. Non-parametric measures S i (1) and S i (2) were used to determine stability of sunflower hybrids. The level of association among stability measures was assessed using Sperman's rank correlation. Significant differences in rank stability among 20 sunflower hybrids grown in 13 (2010) or 15 (2009, 2008) locations were found. According to non-parametric stability parameters S i (1) and S i (2) , hybrids Baća and Vranac were most stable in all locations. Baća also had high oil yield in 2008 and 2009. In 2010 two new hybrids (NS-H-6612, NS-H-2069) were high yielding and stable for oil yield. Hybrid NS-H-111 was also stable in all locations in 2009 and 2010 and its oil yield was above average. The Spearman's rank correlation between non-parametric stability parameters, showed highly significant (P<0.01) rank correlations between S i (1) and S i (2) , indicating that the two measures were similar in classifying the hybrids according to their stability under different environmental (location) conditions. Non-parametric measures of stability, based on ranks, could be recommended to agronomists and plant breeders.