The goal of the study was to assess within bread wheat (Triticum aestivum L.) cultivar variation through honeycomb selection, under the ultra-low density (ULD) of 1.2 plants/m 2 . Divergent selection of individual plants characterized as providing high (H) and low (L) yield led to 10 H and 10 L first generation families, respectively. Further selection of high yielding plants within H families resulted in 20 second generation families. Progeny evaluation was conducted in two locations, under ULD and the typical crop density (TCD) of 500 plants/m 2 . Six of the first generation families were also tested, in two locations for two years, across four densities (100, 300, 500, and 700 plants/m 2 ). Intra-cultivar selection improved yield potential per plant (i.e., expressed under low competition conditions), and there was an indication of overall crop yield potential improvement (i.e., maximum yield per unit area). Compared to the original cultivar at ULD conditions, five of the H first generation and 15 of the second generation families had significantly higher grain yield per plant (by 18 to 53%). Two of the H first generation and four of the second generation families significantly outperformed the original cultivar by 17 to 22% under TCD. Experimentation across the four densities showed that derived families exhibited less density dependence than their original cultivar, a determinant parameter for stability of performance. Results constituted evidence of low densities being more suitable for breeder's seed maintenance, so that any existing or newly developed variation is beneficially exploited.

This brief historical review focuses on durum wheat domestication and breeding in the Mediterranean region. Important milestones in durum wheat breeding programs across the countries of the Mediterranean basin before and after the Green Revolution are discussed. Additionally, the main achievements of the classical breeding methodology are presented using a comparison of old and new cultivars. Furthermore, current breeding goals and challenges are analyzed. An overview of classical breeding methods in combination with current molecular techniques and tools for cultivar development is presented. Important issues of seed quality are outlined, focusing on protein and characteristics that affect human health and are connected with the consumption of wheat end-products.

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The effect of the parental genotypes and colchicine treatment on the androgenic response of wheat (Triticum aestivum L.) F1 hybrids was studied. For this, anthers from three F1 hybrids and their parents were cultured on W14 initiation medium and W14 supplemented with 0.03% colchicine. The number of responding anthers, microspore‐derived structures/100 anthers, green plants/embryos cultured, green plants/100 anthers and albino plants/100 anthers were recorded. It was observed that embryo formation and plant regeneration ability were genetically controlled and genotype dependent. In both treatments the variety Kavkaz had a significantly higher percentage of responding anthers, microspore‐derived structures and green plants/100 anthers than the other genotypes. On the other hand, the variety Myconos also demonstrated high microspore‐derived structure production and green plant regeneration when treated with colchicine. The good response observed in these two varieties indicates the importance of colchicine treatment only for certain genotypes. Green plant production capacity of the hybrids was intermediate to that of the parental varieties. As one parent with a high or even an intermediate response to anther culture could lead to the production of sufficient (for breeding purposes) green plants from the F1 hybrids, it was concluded that screening the inbred lines for the response to anther culture with and without colchicine treatment could contribute to utilization of breeding material with a low response to anther culture via the proper hybrid combinations.

The allelic diversity in seed storage proteins of 25 bread wheat cultivars grown in Hellas was investigated. In total, 15-20 seeds per cultivar were used for the determination of the alleles present at the loci coding for high-molecular-weight glutenin subunits and gliadins. For this purpose, acid polyacrylamide gel electrophoresis for gliadins and SDSelectrophoresis for glutenins were employed. Analysis of the electrophoretic patterns revealed that intravarietal selections obtained from the cultivar ÔNestosÕ, together with the cultivar ÔEurydiceÕ which was selected from the cultivar ÔNestosÕ, were identical to their original cultivar and to the cultivar ÔDodoniÕ. The cultivars ÔPeniosÕ, ÔSiette Cerros EÕ, ÔGorgonaÕ and ÔLourosÕ, although recorded to differ in descent, were found to be identical at all the loci examined. Finally, it was revealed that four of the Hellenic cultivars carry the wheat-rye 1BL/1RS translocation. These data could be beneficial for a better understanding of the existing differences in quality and stress-resistance between the cultivars examined.

The possibility of inducing embryo development after pollination of F1 interspecific cotton hybrids (Gossypium barbadense × Gossypium hirsutum) and their reciprocals with pollen from Hibiscus cannabinus was investigated. For this, flowers of F1 plants from 4 G. barbadense × G. hirsutum interspecific hybrids (B403 × Acala Sindos, Carnak × 4S, B403 × Coker 310, and Carnak × Acala Sindos) and their reciprocals grown in the field were pollinated with pollen from Hibiscus cannabinus. From the 443 pollinated flowers, 276 were left on the plant to grow naturally, and 167 were collected 5 days after pollination. Young ovules from the collected buds were cultured in vitro for embryo development. It was observed that, from the buds left to grow naturally on the mother plant, 21 bolls reached maturity. The mature bolls originated only from the 4 G. barbadense × G. hirsutum hybrids and contained 82 mature seeds. Finally, 38 plants (Pa0) were produced. From the in-ovule culture method, 10 young embryos were isolated from both G. barbadense × G. hirsutum and G. hirsutum × G. barbadense hybrids and finally 3 plants were produced. The plants produced from both approaches originated only from the G. barbadense × G. hirsutum hybrids. These plants exhibited morphological traits from both cotton species and they were partially fertile. No signs of H. cannabinus morphological traits were observed in the plants produced. Root-tip chromosome counts revealed that chromosome number among cells of the Pa0 plants ranged from 27 to 42 and the difference in chromosome number observed among cells of the same plant ranged from 1 to 3. The chromosome number, however, was increased progressively from generation to generation and in Pa3 it ranged from 46 to 52. Plants with 52 chromosomes were identified even from the Pa1 generation. In addition, flow cytometric analysis indicated that the parental plants had a similar DNA profile to the F1 and F2 interspecific hybrids but a different one from the Pa0 plants. Thus, alien pollination of cotton flowers from interspecific (G. barbadense × G. hirsutum and reciprocals) hybrids with pollen from H. cannabinus most likely induced parthenogenetic (Pa) egg cell development which, after a progressive chromosome increase, produced fully fertile plants with most of the cells at the tetraploid or near-tetraploid level. It was concluded that a combination of the in situ boll development with an optimised in vitro ovule culture technique could establish the ‘cannabinus method’ in cotton, as a method for the production of genotype-independent partial interspecific lines.

The Hellenic cultivar Acheron is a good example since, despite the presence of the translocation, it also has very good bread-making quality and high yielding ability. It must be also mentioned that most of the Hellenic durum germplasm carries the gene locus Gli-B1 component, similar to γ45, which can be considered as an index of good end-product quality.

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