Mohammadi, R., Roostaei, M., Ansari, Aghaee, M. and Amri, M. 2010. Relationships of phenotypic stability measures for genotypes of three cereal crops. Can. J. Plant Sci. 90: 819Á830. Multi-environment trial (MET) data are required to obtain stability performance parameters as selection tools for effective genotype evaluation. The main objective of this study was to investigate the interrelationships among nine phenotypic stability methods using grain yield from three sets of cereal experiments [15 durum wheat (Triticum turgidum var. durum) genotypes )12 environments; 20 bread wheat (T. aestivum L.) genotypes)18 environments; and 13 barley (Hordeum vulgare L.) genotypes )18 environments]. The experiments were conducted in representative rain-fed areas of Iran in collaboration with the International Center for Agricultural Research in the Dry Areas (ICARDA). The combined ANOVA for environments (E), genotypes (G) and G )E interaction was highly significant (PB0.01) for each set of data, suggesting differential genotypic responses and the need for stability analysis. The inter-relationships among the parameters and their association with mean yield based on Spearman's rank correlation were determined in each of the three cereal experiments. Highly significant correlations were found between several of the stability measures indicating that several of the statistics probably measure similar aspects of phenotypic stability for these crop species. The AMMI stability value (ASV), variance of regression deviation (S 2 di ) and Wricke's ecovalence (W 2 i ) were consistently and highly correlated with each other over these crops and, therefore, could be used if selection is to be based primarily on stability. The superiority index (Pi) and geometric adaptability index (GAI), which are related to the dynamic concept of stability showed significant correlation with mean yield over these crops, suggesting P i and GAI would be the best methods for ranking genotypes across environments. The coefficient of variation (CV), regression coefficient (b i ), yield reliability index (I i ), and environmental variance (S 2 x ) showed inconsistent relationships with either the static or dynamic concepts of stability over these crops. The correlation analysis provided a good description of static and dynamic concepts of stability for interpreting the G)E interaction and verified that the groups of stability methods (dynamic vs. static) discriminated genotypes in different fashions in these crops.Key words: Rank correlation, phenotypic stability measures, dynamic and static stability Mohammadi, R., Roostaei, M., Ansari, Aghaee, M. et Amri, M. 2010. Liens entre la mesure de la stabilite´du phe´notype et le ge´notype de trois cereals. Can. J. Plant Sci. 90: 819Á830. On a besoin de donne´es multi-environnementales pour e´tablir les parame`tres de la stabilite´qui serviront de moyen de se´lection en vue d'une e´valuation efficace du ge´notype. Cette e´tude avait pour principal objectif d'examiner les relations entre neuf me´thodes d'analyse de...

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Fusarium verticillioides is one of the most common phytopathogenic fungi affecting maize production, worldwide. The early identification of F. verticillioides infection in maize could be helpful to prevent the spreading of the fungus. Therefore, this study represents the use of chlorophyll fluorescence parameters to identify F. verticillioides infection in maize. Chlorophyll a fluorescence of control and F. verticillioides infected plants showed a typical polyphasic OJIP transient curve in both MO17 and B73 lines. Infected plants from both maize lines showed a different pattern of OJIP transient curve when compared to the control plants, respectively. This indicated that F. verticillioides had an effect on the photosynthesis of infected maize plants. This study demonstrated the importance of parameters such as: the activity of the watersplitting complex on the donor side of PSII (F v /F 0), minimum fluorescence (F 0), maximum fluorescence (F m), and absorption flux per one active reaction center (ABS/RC) to identify F. verticillioides infection in maize.

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Collection of wheat landraces (WLR) was conducted in Afghanistan, Iran, and Turkey in 2010–2014. A representative subset of this collection was used in the current study and included 45 bread wheat landraces from Turkey, 19 from Iran, and 20 from Afghanistan. This material was supplemented by 73 modern cultivars and breeding lines adapted to semiarid conditions and irrigated conditions. Overall, 157 genotypes were tested in Turkey in 2018 and 2019 and in Afghanistan and Iran in 2019 under rainfed conditions to compare performance of WLR and modern material. The germplasm was genotyped using a high density Illumina Infinium 25K wheat SNP array and KASP markers for agronomic traits. The average grain yield ranged between 2.2 and 4.0 t/ha depending on the site and year. Three groups of landraces demonstrated similar average grain yield, though Afghanistan material was slightly higher yielding not only in Afghanistan but also in Turkey. Modern material outyielded the landraces in two environments out of four. The highest yielding landraces were competitive with the best modern germplasm. Frequency of gene Sus2-2B affecting 1000 kernel weight was 64% in WLR and only 3% in modern material. Presence of positive allele of Sus2-2B increased 1000 kernel weight by nearly 4%. Breeding strategy to improved landraces and modern cultivars is discussed.

Zymoseptoria tritici is one of the most economically destructive wheat diseases all over the world and is a model fungal plant pathogen within the ascomycetes. In this study, the instrumental role of the ZtRlm1 gene encoding a MADS-box transcription factor (TF) in the infection process of Z. tritici was functionally characterized as these proteins play critical roles in the global gene regulation required for various developmental and physiological processes. Our infection assays showed that ZtRlm1 mutants were attenuated in disease development as a 30 and 90% reduction in chloro-necrotic lesions and pycnidia formation, respectively, were observed in plants inoculated with ZtRlm1 mutant strains demonstrating that ZtRlm1 is a crucial factor playing a significant role in the late stage of infection corresponding with pycnidial formation. Our expression analysis demonstrated that the transcript level of ZtRlm1 is induced at 2 and 20 days post-inoculation, coinciding with pycnidial sporulation. In addition, microscopic analyses showed that branch intensity and biomass production were significantly reduced, indicating that impaired pycnidia formation is a result of impaired differentiation and biomass production in the ZtRlm1 mutants. Furthermore, melanization, a phenomenon required for fruiting body formation, was significantly hampered in ZtRlm1 mutants as they were not melanized under all tested temperature and media conditions. Overall, our data showed that impaired disease development of the ZtRlm1 mutants is mainly due to the significant impact of ZtRlm1 in different cellular processes, including differentiation, branching, fungal biomass production, and melanization, in which identification of downstream genes are of interest to increase our understanding of this pathosystem.

Plant ecotypes represent heterogeneous, local adaptation of domesticated species and thereby provide genetic resources that meet current and new challenges for farming in drought-prone environments. A total of 536 Sardari bread wheat ecotypes, assembled from different geographical regions of Iran, were studied under rainfed cold conditions for three cropping seasons (2009–12). The main objectives were to (i) quantify the performance of the Sardari wheat ecotypes under cold rainfed conditions and (ii) provide information that would enable germplasm management and utilization in wheat breeding programmes to enhance the development of better adapted varieties for the rainfed cold conditions of Iran. All the ecotypes were evaluated for grain yield and several drought-adaptive traits. Combined analysis of variance indicated significant differences between years, ecotypes and their interaction effects for each studied trait. The Sardari wheat ecotypes showed considerable variability for the phenotypic traits and stability performance that could be utilized for wheat improvement in cold rainfed areas. Many of the Sardari wheat ecotypes exhibited a high combination of yield and stability for both drought and cold stresses, comparable to control cultivars. Multivariate analyses indicated several significant patterns among ecotypes from different geographical regions. In conclusion, selection from current Sardari wheat ecotypes may lead to yield stability and specific adaptation, which provides opportunities for this collection to be useful for genetic improvement of drought tolerance in bread wheat.