The main objective of this study was to evaluate the genetic gain for grain yield, yield attributes and drought tolerance of 11 durum breeding lines and also to compare it with one modern cultivar and two durum and bread wheat landraces in contrasting environment groups in a period of four cropping seasons (2005–09) within the Iran/ICARDA joint project for moderately cold rainfed areas of Iran. The significant genotype × year interaction indicated that the average yield performance of genotypes across environments was not consistent over the years. Genetic gain (%) for grain yield was distinguishable between the stressed and non-stressed environments. A positive genetic gain (27.7 to 23.9%) was observed in the non-stressed environment and a negative genetic gain (−11.5 to −24.1%) in the stressed environment for the breeding lines, compared to the landraces, suggesting that the evaluation of breeding materials under non-stressed conditions should be continued. Unlike the modern cultivar, the landraces were low yielding, and less responsive to non-stressed environments for grain yield and yield attributes. The drought resistance indices, i.e. tolerance index (TOL) and stress susceptibility index (SSI), were better in landraces than breeding lines, while the drought tolerance indices, i.e. stress tolerance index (STI) and drought response index (DRI), were better in breeding lines. In contrast with landraces, the modern cultivar and the breeding lines showed significant changes for both grain yield and drought tolerance.
Genotype selection based on multiple traits in multi-years is frequently influenced by unpredictable rainfed conditions. The main objective of the study was to apply the new methodology of genotype by yield*trait (GYT) biplot for genotype selection and trait profiles in durum wheat genotypes based on multi-traits and multi-year data under rainfed conditions of Iran. A superiority index was applied based on GYT table for ranking of genotypes by the mean of all traits. The GYT biplot ranked the genotypes based on their levels in combining yield with other key traits. Grain yield was combined with target traits and showed the strengths and weaknesses of each genotype. Based on GYT-biplots the relationships among the studied traits were not repeatable across years, but they facilitated visual genotype comparisons and selection. The breeding lines G13, G10 and G15 ranked as the best in combination of the morph-physiological traits i.e., SPAD-reading, early heading, flag-leaf length and number of grain per spike with grain yield under rainfed conditions. The results indicate that there is a potential for simultaneous improvement of some characteristics of durum wheat under rainfed conditions. The GYT biplot was a useful tool for exploring the combination of yield with traits and trait profiles of the durum genotypes to obtain high genetic gains in the durum breeding programs.
This research aimed to study the androgenesis and spontaneous chromosome doubling of five barley genotypes using an isolated
microspore culture technique, involving a completely randomized design (CRD) with three replications. Statistical analysis of embryogenesis and cytogenetic results showed that genotype had a significant effect on haploid embryogenesis (P<0.01) and on spontaneous chromosome doubling (P<0.05). The genotype Igri was found to have the highest potential to produce haploid embryos (1577 embryos from 100 anthers), followed by the genotypes Boyer/Rojo, Afzal/Turkman/Kavir, Ashar/Hebo and Agrigashar/Matico with 369, 304, 278 and 150 embryos from 100 anthers, respectively. The highest percentage of spontaneous chromosome doubling (76%) was observed for the genotype which had the lowest embryogenesis (Agrigashar/Matico) and the lowest (65%) for the genotype with the highest androgenic capacity (Igri). Microspore embryogenesis also showed comparatively higher genotypic (109.2) and phenotypic (109.5) coefficients of variation, heritability (99.62) and genetic advance (1206.77), indicating the pre-dominance of additive gene action in the control of this character in the material studied. Estimates of genetic parameters (PCV, GCV and heritability) for microspore embryogenesis were higher than for spontaneous doubled haploids. These results indicated that selection for androgenic capacity would be more effective than for spontaneous doubled haploids. The findings showed a negative relationship (r= −0.68) between embryogenesis and spontaneous chromosome doubling in the barley genotypes studied. All the large embryos used had high regenerability and good plantlet formation.
Authors:R Naderi, G Mohaddes, M Mohammadi, A Alihemmati, R Badalzadeh, R Ghaznavi, R Ghyasi, and Sh Mohammadi
Since some complications of diabetes mellitus may be caused or exacerbated by an oxidative stress, the protective effects of garlic (Allium sativum) were investigated in the blood and heart of streptozotocin-induced diabetic rats. Twenty-eight male Wistar rats were randomly divided into four groups: control, garlic, diabetic, and diabetic+garlic. Diabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (50 mg/kg) in male rats. Rats were fed with raw fresh garlic homogenate (250 mg/kg) six days a week by gavage for a period of 6 weeks. At the end of the 6th week blood samples and heart tissues were collected and used for determination of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and histological evaluation. Induction of diabetes increased MDA levels in blood and homogenates of heart. In diabetic rats treated with garlic, MDA levels decreased in blood and heart homogenates. Treatment of diabetic rats with garlic increased SOD, GPX and CAT in blood and heart homogenates. Histopathological finding of the myocardial tissue confirmed a protective role for garlic in diabetic rats. Thus, the present study reveals that garlic may effectively modulate antioxidants status in the blood and heart of streptozotocin induced-diabetic rats.
To assess the stability and yield performance of safflower genotypes and to identify subregions within Iran, a set of experiments was conducted at six locations during 2003–2005. AMMI model analysis and some stability parameters derived from the grain yield were used. AMMI analysis showed differences between genotypes and environments and the GE interaction was highly significant, indicating that the agro-climatic environmental conditions were different, and that there was a differential response of the genotypes to the environments. The first two IPCA components of the GE interaction explained 51.5% of the GE interaction. According to the AMMI model, G16 was the most superior genotype in 15 out of 18 environments. The biplot of IPCA1 and IPCA2 showed that the six locations represent different environments, and mega-environments in Iran were identified for safflower breeding programmes. Due to the great fluctuation observed when selecting genotypes through stability parameters, it was not possible to distinguish stable genotypes clearly. In addition, when calculating these parameters high yield performance is not considered. So the Yield and Stability Index (YSI) can be recommended as a new approach to facilitate genotype selection, where genotypes with low values of YSI are the best. According to YSI the genotypes G16, G2, G9 and G1 can be selected. These genotypes were also selected using the AMMI model.
In order to locate QTLs controlling field and laboratory indicators of drought tolerance, chromosome addition lines of Agropyron elongatum (donor) in the genetic background of Chinese Spring (recipient) were tested in the field and laboratory of the College of Agriculture, Razi university, Kermanshah, Iran. The plant genetic material was cultivated in the field and laboratory under two different water regimes (irrigated and non-irrigated). High significant differences were found for promptness index (PI), coleoptile length (CL) and root length (RL) under stress and non-stress conditions, indicating the presence of genetic variation and the possibility of selection for these traits. High correlation coefficients were found between PI, germination stress index (GSI) and stress tolerance index (STI), displaying a high association between the indices of field and laboratory predictors of drought tolerance. Field and laboratory predictors of drought tolerance showed that most of the QTLs controlling drought tolerance criteria in Agropyron are located on chromosomes 3E, 5E and 7E, which collectively constitute 84.3% of the additive genetic variance.
Authors:E. Farshadfar, R. Mohammadi, M. Aghaee, and J. Sutka
Water deficiency is a major constraint in wheat production and the most important contributor to yield reduction in the semiarid regions of the world. species related to wheat are valuable genetic sources for different traits including resistance/tolerance to biotic and abiotic stresses. To locate the genes controlling the physiological and agronomic criteria of drought tolerance, disomic addition lines of secale cereale cv. Imperial (donor) into the genetic background of Triticum aestivum cv. Chinese Spring (recipient) were tested under field, greenhouse and laboratory conditions. Disomic addition lines exhibited significant differences for relative water content (RWC), relative water loss (RWL), water use efficiency (WUE) and stomatal resistance (SR), indicating the presence of genetic variation and the possibility of selection for improving drought tolerance. Three physiological variables, RWL, WUE and SR, with high correlation with the stress tolerance index (STI) and germination stress index (GSI), contributed 69.7% to the variability of yield under stress (Ys) in the regression equation. Based on the physiological multiple selection index (MSI) most of the QTLs controlling physiological indices of drought tolerance were located on chromosomes 3R, 5R and 7R. The contribution of addition line 7R to the MSI was 47%. The evaluation of disomic addition lines for STI and GSI revealed that most of the QTLs involved in these quantitative criteria of drought tolerance are located on 3R and 7R. Cluster analysis and three dimensional plots of Ys, yield potential (Yp) and MSI indicated that 3R and 7R are the most important chromosomes carrying useful genes for improving drought tolerance.
Authors:B. Vaezi, A. Pour-Aboughadareh, R. Mohammadi, M. Armion, A. Mehraban, T. Hossein-Pour, and M. Dorii
Successful production and development of stable and adaptable cultivars only depend on the positive results achieved from the interaction between genotype and environment that consequently has significant effect on breeding strategies. The objectives of this study were to evaluate genotype by environment interactions for grain yield in barley advanced lines and to determine their stability and general adaptability. For these purposes, 18 advanced lines along with two local cultivars were evaluated at five locations (Gachsaran, Lorestan, Ilam, Moghan and Gonbad) during three consecutive years (2012–2015). The results of the AMMI analysis indicated that main effects due to genotype (G), environment (E) and GE interaction as well as four interaction principal component axes were significant, representing differential responses of the lines to the environments and the need for stability analysis. According to AMMI stability parameters, lines G5 and G7 were the most stable lines across environments. Biplot analysis determined two barley mega-environments in Iran. The first mega-environment contained of Ilam and Gonbad locations, where the recommended G13, G19 and G1 produced the highest yields. The second mega-environment comprised of Lorestan, Gachsarn and Moghan locations, where G2, G9, G5 and G7 were the best adapted lines. Our results revealed that lines G5, G7, G9 and G17 are suggested for further inclusion in the breeding program due to its high grain yield, and among them G5 recommended as the most stable lines for variable semi-warm and warm environments. In addition, our results indicated the efficiency of AMMI and GGE biplot techniques for selecting genotypes that are stable, high yielding, and responsive.
Authors:A. Etminan, A. Pour-Aboughadareh, R. Mohammadi, A. Noori, and A. Ahmadi-Rad
Progress in plant molecular tools has been resulted in the development of gene-targeted and functional marker systems. CAAT box region is a different pattern of nucleotides with a consensus sequence, GGCCAATCT, which situated upstream of the start codon of eukaryote genes and plays an important role during transcription. In the present study, several CAAT box-derived polymorphism (CBDP) primers were used for fingerprinting in mini-core collection of durum wheat (including internationally developed breeding lines and Iranian landraces). Twelve selected primers amplified 98 loci, of which all were polymorphic. The average values of the polymorphism information content (PIC) and resolving power (Rp) were 0.31 and 9.16, respectively, indicating a high level of variability among studied genotypes. Analysis of molecular variance (AMOVA) indicated that 92% of the total variation resided among populations. The values of the percentage polymorphic bands (PPL), the observed (Na) and effective (Ne) number of alleles, Nei’s gene diversity (He) and Shannon’s information index (I) for Iranian landraces were higher than the breeding lines. The Fandendrogram obtained by cluster analysis grouped all individuals into three main clusters. Our results showed a remarkable level of genetic diversity among studied durum wheat, especially among Iranian landraces, which can be interest for future breeding programs. More importantly, the present study also revealed that CBDP technique was efficient and powerful tool to assess genetic diversity in wheat germplasm. Hence, this technique could be employed individually or in combination with other molecular markers to evaluate genetic diversity and relations among different species.
Authors:R. Prasanna, S. A. Mohammadi, B. M. Prasanna, and P. K. Singh
Twenty cyanobacterial strains of the genus Tolypothrix, including 15 strains of T. tenuis, three strains of T. ceylonica, and one each of T. nodosa and T. bouteillei, that were collected from various agro-ecological regions of India were evaluated for important parameters related to nitrogen fixing potential, such as acetylene reduction activity, total protein and chlorophyll content. Distinct differences were observed in nitrogen fixing potential at both inter- and intraspecific levels. The T. tenuis strains, in general, exhibited superior nitrogen fixing ability as compared to strains belonging to other species. A statistical procedure based on simultaneous consideration of performances of various strains with respect to different parameters under study aided in identification of three highly promising T. tenuis accessions, namely ARM586, ARM75 and ARM460, for potential exploitation as biofertilisers.