SummaryDespite some notable successes, only a fraction of the genetic variation available in wild relatives has been utilized to produce superior wheat varieties. This is as a direct result of the lack of availability of suitable high‐throughput technologies to detect wheat/wild relative introgressions when they occur. Here, we report on the use of a new SNP array to detect wheat/wild relative introgressions in backcross progenies derived from interspecific hexaploid wheat/Ambylopyrum muticum F1 hybrids. The array enabled the detection and characterization of 218 genomewide wheat/Am. muticum introgressions, that is a significant step change in the generation and detection of introgressions compared to previous work in the field. Furthermore, the frequency of introgressions detected was sufficiently high to enable the construction of seven linkage groups of the Am. muticum genome, thus enabling the syntenic relationship between the wild relative and hexaploid wheat to be determined. The importance of the genetic variation from Am. muticum introduced into wheat for the development of superior varieties is discussed.

Wheat (Triticum aestivum) is one of the most important food staples in the south of Brazil. Understanding genetic variability among the assortment of Brazilian wheat is important for breeding. The aim of this work was to molecularly characterize the thirty-six wheat cultivars recommended for various regions of Brazil, and to assess mutual genetic distances, through the use of microsatellite markers. Twenty three polymorphic microsatellite markers (PMM) delineated all 36 of the samples, revealing a total of 74 simple sequence repeat (SSR) alleles, i.e. an average of 3.2 alleles per locus. Polymorphic information content (PIC value) calculated to assess the informativeness of each marker ranged from 0.20 to 0.79, with a mean of 0.49. Genetic distances among the 36 cultivars ranged from 0.10 (between cultivars Ocepar 18 and BRS 207) to 0.88 (between cultivars CD 101 and Fudancep 46), the mean distance being 0.48. Twelve groups were obtained by using the unweighted pair-group method with arithmetic means analysis (UPGMA), and thirteen through the Tocher method. Both methods produced similar clusters, with one to thirteen cultivars per group. The results indicate that these tools may be used to protect intellectual property and for breeding and selection programs.

RESUMO -Este trabalho teve como objetivo avaliar os efeitos do arranjo espacial e da densidade de semeadura na produtividade de cinco híbridos de milho, em dois locais no cultivo de verão. Foram utilizados espaçamentos de 80 cm e de 45 cm entrelinhas, e densidades de semeadura de 42.000, 52.000, 62.000 e 85.000 plantas ha COMBINING ROW SPACING AND POPULATION DENSITY IN INCREASING MAIZE YIELDABSTRACT -This study aimed to evaluate the effects of spatial arrangement and plant density from five corn hybrids at two locations in the summer season. Row spacing used were 80 cm and 45 cm between rows and plant densities were 42,000, 52,000, 62,000 and 85,000 plants ha -1 . The evaluations were conducted in Cascavel, State of Paraná, and RioVerde, State of Goiás, Brazil. Significant effects were observed for the main effects (hybrid, row spacing and density), but there were no interactions between the main effects, with the exception of the interaction between density x hybrid in Rio Verde. There was a greater effect of row spacing than the population density on yield of all hybrids. With the row spacing at 45 cm the hybrids yielded, on average, 36% more than at a spacing of 80 cm, in the two locations. There was a trend for increased productivity with increased seeding rate up to 75,000 plants ha -1 in Cascavel, and up to 85,000 plants ha -1 in Rio Verde.

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Transgenic technology is an excellent alternative for improvement of crop production and disease free crops such as potato, which is one of the most important crops worldwide. One of the first steps to apply the transgenic technique is the establishment of an efficient plant regeneration protocol. This is a limiting step in this kind of study, since most protocols are species-specific and some of them do not adequately respond to in vitro culture or present low regeneration rates. The objective of this study was to stablish an efficient regeneration protocol of Solanum tuberosum cv. Monalisa from internodes explants. This work is important since most in vitro protocols are based on shoots. Twenty five treatments were performed, with each treatment being composed of six internodes in flasks containing MS medium supplemented with a fixed concentration of zeatin riboside (3 mg.L-1) (ZEA), varying concentrations of naphthaleneacetic acid (0 to 1 mg. L-1) (NAA), and gibberellic acid (0 to 3 mg.L-1) (GA 3). The treatment composed of ZEA, 0.05 mg.L-1 of NAA, and 0.10 mg.L-1 of GA 3 was considered the best for shoot regeneration from potato internodes. The study was able to establish a specific regeneration protocol for Monalisa cultivar. This result can be very useful since it is possible to obtain plants from internode, without the requirement of meristematic regions, enabling the obtainment of a higher number of plants.

Abiotic stresses are the major cause of yield loss in crops around the world. Greater genetic gains are possible by combining the classical genetic improvement with advanced molecular biology techniques. The understanding of mechanisms triggered by plants to meet conditions of stress is of fundamental importance for the elucidation of these processes. Current genetically modified crops help to mitigate the effects of these stresses, increasing genetic gains in order to supply the agricultural market and the demand for better quality food throughout the world. To obtain safe genetic modified organisms for planting and consumption, a thorough grasp of the routes and genes that act in response to these stresses is necessary. This work was developed in order to collect important information about essential TF gene families for transcriptional control under abiotic stress responses.

Within the MADS-box gene family, the AGAMOUS-subfamily genes are particularly important for plant reproduction, because they control stamen and carpel identity. A number of studies in the last three decades have demonstrated that the AGAMOUS (AG) function has been conserved during land plant evolution. However, gene duplication events have led to subfunctionalization and neofunctionalization of AG-like genes in many species. Here we show that alternative splicing in Oryza sativa produces two variants of the AG ortholog OsMADS3 which differ in just one serine residue, S109. Interestingly, this alternative splicing variant is conserved and specific to the grass family. Since in eudicots the S109 residue is absent in AG proteins, stamen and carpel identity determination activity of the two rice isoforms was tested in Arabidopsis thaliana. These experiments revealed that only the eudicot-like OsMADS3 isoform, lacking the serine residue, had ability to specify stamens and carpels in ag mutant flowers, suggesting an important functional role for the serine residue at position 109 in AG proteins of grasses.