Evaluation of genotype x environment interactions in maize hybrids using GGE biplot analysis

Seventeen hybrid maize genotypes were evaluated at four different locations in 2005 and 2006 cropping seasonsunder irrigated conditions in Turkey. The analysis of variance showed that mean squares of environments (E), genotypes (G) andGE interactions (GEI) were highly significant and accounted for 74, 7 and 19 % of treatment combination sum squares, respectively.To determine the effects of GEI on grain yield, the data were subjected to the GGE biplot analysis. Maize hybrid G16 can be proposedas reliably growing in test locations for high grain yield. Also, only the Yenisehir location could be best representative of overalllocations for deciding about which experimental hybrids can be recommended for grain yield in this study. Consequently, using ofgrain yield per plant instead of grain yield per plot in hybrid maize breeding programs could be preferred by private companies dueto some advantages

Books Received

WOS: 000324163700028In this study, estimation of narrow sense heritability, genetic correlations and relative effects of direct versus indirect selection were aimed for peduncle length, spike length, number of spikelet per spike and number of kernels per spike as selection was applied for shorter plant height in common wheat population of (Golia x Atilla-12) cross. While the indirect effect of direct selection for plant height was observed negative on number of kernels per spike, positive effect was obtained on peduncle length. It was understood that selection of peduncle length can be done indirectly through the selection for short plant height in the (Golia x Atilla-12), but while it had no effect on other components. Therefore, it was concluded that direct selection for short plant height can be done successfully, and on various selection practices and studies are necessary for the spike length, number of spikelet per spike and number of kernels per spike. (C) 2013 Friends Science Publisher

Identification of resistance to Eurygaster integriceps Put. on some bread wheat genotypes

Sunn pest (Eurygaster integriceps Put.) is one of the most important pests of wheat in Eastern Europe including Turkey, West and Cen-tral Asia. Its damage on leaves, stems, spikes and grains reduce the baking quality of flour made from damaged grains. In this study, some wheat genotypes from Turkey and ICARDA were evaluated for the pest resistance. The genotypes were planted in a randomized block design using hill plots in nylon mesh screening cages in wheat growing season of 2011-2012 and 2012-2013. Sunn pest population was collected from Çanakkale province, where the pest was intensely found in recent years. The plants of each hill plots were infested with one male and one female Sunn pest adults. The results with 12.5% sucking damage showed that the genotypes from ICARDA had higher resistance than the landraces from Turkey to Sunn pest. Especially, the genotypes IC3 and IC4 from ICARDA and TR7 from Turkey with respect to their SED and DSED values were found the most promising genotypes resistant to Sunn pest for future breeding programs

Exploring the genetic diversity and population structure of wheat landrace population conserved at ICARDA genebank

Landraces are considered a valuable source of potential genetic diversity that could be used in the selection process in any plant breeding program. Here, we assembled a population of 600 bread wheat landraces collected from eight different countries, conserved at the ICARDA's genebank, and evaluated the genetic diversity and the population structure of the landraces using single nucleotide polymorphism (SNP) markers. A total of 11,830 high-quality SNPs distributed across the genomes A (40.5%), B (45.9%), and D (13.6%) were used for the final analysis. The population structure analysis was evaluated using the model-based method (STRUCTURE) and distance-based methods [discriminant analysis of principal components (DAPC) and principal component analysis (PCA)]. The STRUCTURE method grouped the landraces into two major clusters, with the landraces from Syria and Turkey forming two clusters with high proportions of admixture, whereas the DAPC and PCA analysis grouped the population into three subpopulations mostly according to the geographical information of the landraces, i.e., Syria, Iran, and Turkey with admixture. The analysis of molecular variance revealed that the majority of the variation was due to genetic differences within the populations as compared with between subpopulations, and it was the same for both the cluster-based and distance-based methods. Genetic distance analysis was also studied to estimate the differences between the landraces from different countries, and it was observed that the maximum genetic distance (0.389) was between the landraces from Spain and Palestine, whereas the minimum genetic distance (0.013) was observed between the landraces from Syria and Turkey. It was concluded from the study that the model-based methods (DAPC and PCA) could dissect the population structure more precisely when compared with the STRUCTURE method. The population structure and genetic diversity analysis of the bread wheat landraces presented here highlight the complex genetic architecture of the landraces native to the Fertile Crescent region. The results of this study provide useful information for the genetic improvement of hexaploid wheat and facilitate the use of landraces in wheat breeding programs

Ekmeklik buğday İzmir 85 çeşidinde ve Thatcher yakın izogenik hatlarında kahverengi pas dayanıklılık geni Lr13’ün SSR markörleriyle incelenmesi

In this research, SSR (Simple Sequence Repeat) markers for brown rust resistance gene Lr13 were screened in Thatcher near isogenic lines containing 41 different resistance genes. Same markers were tested in susceptible local variety İzmir 85, near isogenic line (the line of 12 number) containing Lr13 and F1 generation of the cross between this variety and the line. One of the four SSR markers examined (GWM630) generated a specific band pattern in the line carrying Lr13. This band pattern was observed in the susceptible parent and F1 generation, too. This result is suggested that susceptible parent İzmir 85 variety may have Lr13. Individual DNA and DNA bulks were constructed from Thatcher near isogenic lines and it was concluded that such an application can be useful in terms of time and cost of the molecular researches including Thatcher near isogenic lines.Bu çalışmada, kahverengi pas dayanıklılık geni Lr13’e ait SSR (Simple Sequence Repeat) markörleri, 41 farklı dayanıklılık geni taşıyan Thatcher yakın izogenik hattında incelenmiştir. Duyarlı yerli çeşit İzmir 85, Lr13 genini taşıyan yakın izogenik hat (12 No’lu hat) ve bunlar arasında yapılan melezlemenin F1 generasyonunda aynı markörler kullanılmıştır. İncelenen dört SSR marköründen bir tanesi (GWM630) Lr13 genini taşıyan hatta özgün bir bant deseni vermiştir. Bu bant deseni duyarlı ebeveyn ve F1 generasyonunda da aynı gözlenmiştir. Bu sonuç, duyarlı ebeveyn İzmir 85 çeşidinin Lr13 genini taşıyabileceğine işaret etmektedir. Thatcher yakın izogenik hatlarından bireysel DNA ve DNA bulkları oluşturulmuş ve böyle bir uygulamanın Thatcher yakın izogenik hatlarının dahil olduğu moleküler çalışmaların süresi ve maliyeti açısından faydalı olabileceği kanısına varılmıştı

Ekmeklik Buğday Yerel ve Ticari Çeşitleri ile İleri Islah Hatlarında Genoma Dayalı İlişkilendirme Çalışmaları (GWAS) ve İki Ebeveynli Haritalama Populasyonları Kullanılarak Sarı Pasın Fide ve Ergin Bitki Dayanıklılığının Fenotipik ve Moleküler Karakterizasyonu

Sarı pas hastalıgı Puccinia striiformis Westend f. sp. tritici (Pst) fungusunun neden oldugu küresel bugday üretimi için önemli bir tehdittir. Dünya?daki bugday üretim alanlarının %88?inin sarı pasa hassas oldugu ve bu nedenle yıllık 5 milyon tondan fazla bugday kaybının oldugu düsünülmektedir. Dayanıklılık genlerinin kırılması, yeni ve saldırgan ırkların olusması sarı pasa karsı dayanıklılık çalısmalarını daha önemli ve sürekli kılmaktadır. Bu projede farklı ülkelerden orijinini alan yerel bugday çesitlerinden olusan bir iliskilendirme haritalama populasyonu ile iki ebeveynli katlanmıs haploid ve F2 populasyonları materyal olarak kullanılmıstır. Son yıllarda Dünya?da ve ülkemizde virülent olarak önemli kayıplara neden sarın pasın Yr27 ve Warrior ırklarının, belirtilen üç populasyonda fide ve ergin bitki dönemi testlemeleri Bölgesel Tahıl Pas Arastırma Merkezi bünyesinde gerçeklestirilmistir. Ayrıca üç populasyonun da Genotyping by Sequencing (GBS) metodu kullanılarak SNP genotiplemesi gerçeklestirilmistir. Iliskilendirme haritalama populasyonunda SNP markörleri ile Mixed Linear Model (MLM) kullanılarak GWAS analizi yapılmıstır. Katlanmıs haploid ve F2 haritalama populasyonlarında dayanıklılıkla iliskili QTL bölgelerinin saptanması için SNP markörleri Windows IciMapping v4.1 programında analiz edilmislerdir. F2 haritalama populasyonunda QTL analizleri sonucunda önemli bulunan 2A, 1B ve 2D kromozomları daha önce SNP analizi ile belirlenen iliskili bölgeyi daraltmak amacıyla SSR markörleri ile taranmıstır. Iliskilendirme haritalama populasyonunda toplam 152.000 adet SNP markörü belirlenmis ve bunlardan yüksek kalitedeki 25.169 SNP markörü GWAS analizinde kullanılmıstır. GWAS analizleri sonucunda ergin ve fide dayanıklılıgı ile önemli ölçüde iliskili 17 kromozom üzerinde toplam 40 SNP markörü tespit edilmistir. Fide dayanıklılıgı ile iliskili 3A ve 7D kromozomları üzerinde önemli olarak bulunan 2 genomik bölge (QYr.3A_seedling ve QYr.7D_seedling) yeni sarı pas dayanıklılık lokusları olarak belirlenmistir. Katlanmıs haploid populasyonunda SNP verilerinden ergin bitki dayanıklılıgı ile iliskili olarak toplam 6 QTL belirlenmistir. 3D ve 7D kromozomlarında belirlenen önemli iki genomik bölge önceden tanımlanan sarı pas dayanıklılık genlerinden ve QTL'lerinden uzakta haritalanmıs ve bu nedenle muhtemel yeni sarı pas dayanıklılık lokuslarını isaret etmistir. F2 populasyonunda SNP verilerinden ergin bitki dayanıklılıgı ile iliskili olarak altı farklı genomik bölgede (1B, 2A, 2B, 2D, 5A ve tanımlamayan kromozom) sekiz QTL önemli olarak belirlenmistir. Aynı populasyonda SSR analizleri sonucunda 2A kromozomu üzerinde ergin bitki dayanıklılıgı ile iliskili 2 QTL saptanmıstır