پژوهشنامه اصلاح گیاهان زراعی
پیاپی 21 (بهار 1396)

Rice is one the most important crops in Iran and worldwide. Abiotic stresses including drought, restrict rice production. In order to saturation of linkage map in recombinant lines population caused by Sepidroud × Anbarbou crosses, an experiment was conducted using 96 recombinant lines and 40 ISSR markers at Gonbad Kavous University. 96 Recombinant lines were plant under hydroponic conditions for mapping of traits related to drought stress. Shoot weight, root weight, biomass, genetic score, leaf area, shoot length, root length and root thickness were recorded. Linkage map covered 1709.29 cM of rice genome. Four QTLs mapped on chromosomes 3(2 QTLs) and 7 (2QTLs) in drought. qDRW-3 and qDBM-3 with LOD=2.518 and 2.727 had positive additive effects on root weight and biomass, respectively and explained 11.4 and 12.3% of phenotypic variation. The results of present work can be used for improvement of drought tolerance in rice seedlings after determining marker validation.

In order to assess the relationship of grain yield and some of the agronomic traits recombinant inbred lines (RIL) population of bread wheat derived from the Roshan × Sabalan were used to detect the informative traits on grain yield as the suitable criteria for indirect selection and path coefficient analysis. Two hundred and sixty seven recombinant inbred lines with three control cultivars (Roshan, Sabalan (as parents) and Mahdavi) were evaluated in Augmented design. This experiment was conducted at Shahid Bahonar University of Kerman on growing season of 91-92 Different inbred lines showed significant transgressive segregation for grain yield and its components. Grain yield had significant correlation with all the components. Four traits were entered in the stepwise of regression model containing: total spikes weight, number of fertile trills, main spike weight and number of grain per plant which totally justified 63.7 percent of grain yield variation. The first trait that entered in this model was total spikes weight, it was justified the highest variation of the yield. Due to the result of path analysis, total spikes weight had the most direct effect on grain yield (0.336) and the most indirect effect on number of grain per plant through total spikes weight on grain yield (0.293). Among four traits entered in regression model, the most important trait for improving of seed yield was total spikes weight. Regarding to the high correlation of total spike weight with grain yield, its high direct effect and correlation response for grain yield (1.35), it can be introduced the most effective trait for grain yield improvement.

The genetic diversity of 19 bitter vetch landraces (Vicia ervilia L.) from four provinces (East Azerbaijan, West Azerbaijan, Ardabil and Zanjan) of Iran was evaluated using 18 pairs of SSR primers. The extracted genomic DNA was amplified with eight pair primers and PCR products were separated on DNA sequencing gels. In this research, eight pair of SSR primers detected a total of 27 alleles. Primers VE02, VE05, VE07, VE09 and VE19 with four alleles had the highest and VE14 and VE27 with two alleles had the lowest number of alleles among the SSR markers employed. The average of observed heterozygosity was 0.0435. According to Chi-square test, populations were out of Hardy–Weinberg equilibrium. The results showed that the average of polymorphism information content (PIC) of primers was 0.5363. Primer VE02 had the highest PIC (0.6934) and primer VE27 had the lowest PIC (0.1093). The highest genetic distance was observed between Ardabil (from Ardabil province) with Chumalu (from Zanjan province) landraces. The least genetic distance was observed between Barazin (from East Azerbaijan province) and Khiarak (from Ardabil province) landraces. Cluster analysis based on Nei similarity coefficient matrix using UPGMA method classified the landraces into five main groups. The results indicated that SSR markers are efficient in case of polymorphism detection and genetic distance evaluation between Iranian bitter vetch landraces, and can be used as valuable tools in analysis of genetic relationships between bitter vetch landraces.

27 different populations of Triticum boeoticum were gathered from west and North West of Iran for their grouping using morphological traits. All populations were assessed in farm based on completely random design with three replications in 1393. The measured traits include stem length with spike, spike length with and without awn, awn length, flag leaf length, the woolly leaves, peduncle length, spikelet length, number of grains per spikelet and 100-grain weight. The result showed that the most diversity were observed in hairy leaf and flag leaf length traits according to the variation coefficient in studied traits. All populations are located in three groups based on cluster analysis. Obtained grouping was not agreed with geographical grouping and showed more diversity into populations gathered from the same province. Based on factor analysis, three factors were recognized that explain 76.65 percent of total variation. The first factor allocation of 30.09 percent of the total variation is mainly explained by the traits of hairy leaf, spike length with awn, awn length, grain number per spikelet and was named as a spike morphology factor. The second factor is explained 23.12 percent of the total variation and named length factor and third factor allocation 23.12 percent of the total variation and name were grain filling factor. Biplot figure based on two first factor, all populations were placed on three groups. The obtained results from factor analysis were conformed the result of cluster analysis and confirmed them. The result indicated that when two first factors legitimized high percent of variation, can be used for grouping.

In order to assessment of relationships between effective traits on grain yield and also determination of cause and effect relationships between of them, 121 native and exotic cultivars available in the collection of Rice Research Institute of Iran were evaluated in a simple lattice design (11×11) with two replications for 12 important agronomic traits. The results of analysis of variance showed a significant difference between studied genotypes for all traits at the 0.01 probability level. Phenotypic and genotypic coefficients of variation for most traits were high, indicating high variability in studied genotypes for evaluated traits. Simple correlation coefficients between traits showed that 100-grain weight, number of filled and unfilled grain per panicle, number of tiller and also leaf length and width traits have a significant correlation with grain yield. In multiple regression analysis by stepwise method, 100-grain weight, number of tiller, leaf length, number of filled grain per panicle and leaf width traits were entered into model, respectively, that explained 81 percent of grain yield variations. Also based on path analysis results, 100-grain weight (1.411) and number of filled grain per panicle (1.254) traits have the most and positive direct effect with grain yield and thus, these traits could be considered as selection criteria for grain yield improvement in rice.

Basically, the most important limiting factor in plant growth is the lack of water. More lands in Iran are located in arid and semi-arid region and so identifying of ghenotype that can produce acceptable yield under drought conditions is essential. In order to identification of drought stress tolerant varieties, 20 wheat cultivars were evaluated at three stress levels (control, -0.6 and -1.2 MPa) and in aquaculture medium as a factorial experiment based on completely randomized block design with three replications in the green house of Mohaghegh Ardabili University based on root length, root and shoot fresh weight, root and shoot dry weight and root/shoot dry weight ratio. Stress levels were induced by using polyethylene glycol 6000. Results of ANOVA showed that the stress levels had significant effect on all traits. Also, Cultivars had significant differeces in all traits. The cultivars×stress interaction was significant in all studied traits. The drought tolerance indices of HARM, GMP, MP and STI were calculated based on yield in control (Yp) and stress levels (Ys). Results of ANOVA for indices showed significant difference between cultivars that showed different response of cultivars to drought stress. Comparisons of means were carried out by Duncan's method at one percent probability level. In all of traits the means of cultivars reduced by increasing of stress levels. According to cluster analysis results based on morphological traits in control level, the cultivars of Arta, BC Roshan, Tajan, Gascozen and shiroodi were beter than other cultivars. In -0.6 MPa stress level, the Arta, Shiriidi, Tajan, Kavir and Gascozen cultivars wre tolerant and Moghan2, Rasul and Mihan had partial tolerant to drought stress. In -1.2 MPa stress level, the Kavir, Rasul, Mihan were tolerant to stress. Totally, according to cluster analysis based on morphological traits and tolerance indices, the Rasul and Mihan cultivars were identified as tolerant cultivars.

Salinity is one of a major abiotic stress, specifically on arid and semi-arid areas that has influenced on crop growth and reduced grain yield. The purpose of present study was identification of agronomic traits related to wheat grain yield variation under control and salinity conditions. In order to produce a population of 272 recombinant inbred lines (RILs), a cross between two bread wheat cultivars, namely Roshan and Sabalan, was made and the resulted seeds were cultivated under control and saline conditions at a research field of Yazd during 2011-2012 cropping season. The trial was arranged in an alpha-lattice design with two replications. Grain yield, harvest index, biological yield, 1000-kernel weight, grain weight per spike, number of grain per spike, height plant was evaluated on harvest time. In order to study relationship between wheat grain yield and some agronomic traits in both control and stress conditions was used five statistical methods including simple correlation, multiple linear regression, stepwise regression, principle component analysis and factor analysis. The results were indicated that biological yield and harvest index were the most important variable explained grain yield under both sets of conditions. Therefore, grain yield can be increased with biological yield and harvest index enhancement under control and stress conditions.

Wild melon (Cucumis melo var. agrestis) commonly known as African melon grows in tropical and semi tropical regions of the world. It also known as a valuable medicinal plant has numerous pharmaceutical properties and is considered as a valuable germplasm in cultivated melons breeding. In the present study, genetic variation of sixteen wild melons, collected from Mazandaran province, was examined by 10 AFLP markers. In total, 564 bands were generated and more than 68% were polymorphic. Mean Polymorphic Information Content (PIC) and Marker Index (MI) values were 0.22 and 15.51, respectively and primer (E-CCA/M-CAG) indicated the highest MI, accounting 24.19. In addition, primer (E-CCA/M-CAG) showed the highest diversity with a Shannon Index 0.33. Cluster analysis using Jaccard similarity method and UPGMA algorithm, and Bayesian method, grouped all genotypes in five main groups. Results of Principal Coordinate Analysis were similar with the results based on Bayesian model and the cluster analysis. Genetic diversity determined based on AFLP markers confirmed the efficiency of AFLP for classifying wild melon genotypes according to the geographical origins and such markers can be used to identify differences within species in the genealogy studies.

Anthemis hyalina DC. is one of the most important herbal medicine plants and is used for anti-allergy and curing skin rashes or acne. To date there is no report for in vitro culture of this species and the present study was performed for the first time with the aim of obtaining the optimized treatment for shoot regeneration. In this research the effect of different plant growth regulators NAA (0, 0.1, 0.5, 1.5 mg L-1) and BA (0, 1, 3 mg L-1) on callus induction and shoot regeneration in leaf and immature embryo explants was investigated. This experiment has been carried out as factorial in a completely randomized design with four replications. The results showed the significant effects of all main factors and interactions on measured traits in 0.01 probability level. The highest frequency of shoot regeneration for leaf explant was observed on the medium containing 1 mg L-1 BA. In embryo explant the best treatment for shoot regeneration was 3 mg L-1 BA.

Estimation of genetic variation is very important in breeding programs and existing of high genetic variation lead to increase the response to selection. The objective of this study was to investigate genetic variation for agronomic traits and yield components in 12 alfalfa half-sib families. Thirty five individuals of each half-sib family were grown and analyzed basis of completely randomized design in separate pots into Farm conditions. Based on univarite analysis of variance for all traits except shoot fresh weight, leaf dry weight and leaf/stem ratio significant difference were observed. The heredity was broad ranging from 4 % for plant fresh weight and shoot dry weight to 58 % for cotyledon leaf length. Cluster analysis based Ward method, divided half-sib families into four groups that only the Renger half-sib families, one of the two cultivars stand in one group.

Breeding for environmental stress is one of the most important goals in plant breeding. Among stresses, drought stress has high influencing on limitation of maize production. Therefore, in order to find the best drought tolerant hybrids, 38 maize hybrids were planted in two separate experiments: one with optimum irrigation (control) and another with water stress at grain-filling stage in Moghan at two years. RBCD experiment design with three replications was used. Stress Susceptibility Index (SSI), Mean Productivity (MP), Tolerance (TOL), Geometric Mean Productivity (GMP) and Stress Tolerance Index (STI) indices were used to evaluate susceptibility and tolerance of the genotypes. Results showed that, K74/2-2-1-3-1-1-11×K3653/2 and SC704 hybrids had higher grain yield than mean in all irrigation conditions. These hybrids had the highest STI and located at part of high yield potential and low sensitivity to drought in the biplot. On the other hand, paternal line of majority of drought stress tolerant hybrids was the line K3653/2. Therefore, it is recommended to use this line in breeding maize to get to the most tolerant hybrid. Also the results showed that despite ofthe MP,GMPandSTI indices were most successful in selecting high yield tolerant hybrids, however using biplot the most tolerant hybrids to drought can be chosen the best.

In order to identify the relationships between photoperiod effects on flowering time in barley and four specific genes (FT2, FT3, FT4 and Ppd-H1), 26 cultivated and wild genotypes were studied in both greenhouse and filed conditions. The Plants were grown at two conditions and phenological traits of days to 50% flowering were recorded in both situations. In addition, the morphology of the 11 traits were measured separately in greenhouse conditions. Marker-trait assosiation showed that Ppd-H1 gene had the most significant negative correlation with days to flowering in both conditions, indicating dominant allele Ppd-H1, reduced the number of days to flowering under long day conditions. Marker was significantly associated with the trait of day to flowering was used in regression analysis and represented the largest variation in Ppd-H1 in both conditions and explained the expression of this gene has a major role in the number of days to flowering. In conclusion, genotypes with dominant Ppd-H1 allele are introduced as the best for using in breeding programs and for growing in the areas with short growing seasons.

In the present study, the effect of temperature pretreatment (T1=4 and T2= 8 C) for 10 days on anthers of six different genetic compositions of Ghaem with other high-yielding lines of rice have been studied. For callus induction, three modified culture media of N6 (N1, N2 and N3) and MS culture medium was used for regeneration. results of statistical analysis showed that there was significant difference (P

To evaluation of genetic parameters of rooting traits in 50 doubled haploid barley lines, a factorial experiment based on CRD was carried out at the agronomy lab of the Zanjan University. Analysis of variance showed significant differences for all rooting traits:material transfering speed, germination percent, angle, diameter, fresh and dry weight, surface area, cumulative length, the length of the longest root and the hairy root length. The calculated narrow sense heritability was medium for all studied rooting traits except dry root weight (15.11 and 23.40 in normal and stress conditions). Based on the genotypic correlations, it was found that there were positive and highly significant association normal and salt stress conditions, especialy between trait the length of the longest root and traits cumulative root length, root surface and fresh dry root weight. Since, the length of the longest root and cumulative root length and root surface offered as suitable traits for evaluating and selecting the genotypes in breeding programms.

Grain hardness is the main factor for classification and end-use quality of wheat. Wheat with the hard grain texture has higher protein content and more intensive gluten that leads to production of higher bread quality. However, soft texture wheat has lower protein content and weaker gluten, which are suitable for cake and candy production. Grain hardness is determined by the Pina and Pinb genes that are located on the short arm of chromosome 5D. In this study, 83 bread wheat cultivars were characterized for the allelic distribution of Pina and Pinb genes using allele specific markers. At the Pina locus, Pina-D1a and Pina-D1b alleles were observed in 64% and 36% of varieties, respectively. However, at the Pinb locus, 90% of varieties showed Pinb-D1a and 10% had Pinb-D1b allele. Based on the grain hardness index which was measured with NIR, varieties whit the value less than 50 was considered as soft while above 50 was considered as hard grain texture. The results of marker-trait association showed that Pina had the significant effect (P= 0.019) on the grain hardness, as cultivars with the Pina-D1a allele were significantly softer (49.850.37) that those with the Pina-D1b allele (51.380.50). The results of regression analysis showed that for the traits including bread volume, grain hardness and water absorption as dependent variables, Pina was entered to the model. The results of this study can help wheat breeders for effectively selecting parents for the grain hardness in the MAS breeding programs.

Mutation breeding as an alternative to conventional breeding, is commonly used to improve current varieties and to generate new varieties. Genetic variation in rice is very low, because of its self-pollination. This study, carried out to determine the GR50 dosage for an irradiation mutagenesis study on the rice and to determine the effects of gamma irradiation on germination and growth rate of rice seedlings. The elite seeds of landrace rice CVs. Anbarbo and Gerdeh after moisture regulation (11-13%) were exposed to 100, 200, 250, 300, and 350 Gy doses of gamma irradiation from 60Co and then grown under greenhouse and laboratory conditions. In both conditions, the experiment was a factorial design laid out in a completely randomized design with four replications. The results showed that the lowest values of germination parameters were observed under 350 Gy gamma irradiation. Also, the results showed that with an increase in gamma irradiation dose, the growth rate of both cultivars of rice decreased. In this respect, the decrease of growth rate has a linear relationship with the gamma irradiation dose. Results demonstrated that with increasing of gamma irradiation dose the plantlet height, survival percentage, the number and length of root and leaf in the both conditions were decreased. Gerdeh variety showed a greater degree of sensitivity to gamma irradiation than the Anbarbo variety. Based on our results, 327 and 287 Gy doses of gamma irradiation were selected for the maximum mutation in Anbarbo and Gerdeh, respectively. Finally, in both cultivars, dosages ranging from 250 to 350 Gy are recommended as the appropriate dose of irradiation to create genetic variation for mutation breeding programs.

Due to the limited Alyssum habitats (Alyssum homalocarpum) in rangeland ecosystems, it is necessary to study various aspects of plant growth under different environmental conditions such as abiotic stresses. The aim of this study was to evaluate the effect of salinity and drought on Alyssum seed germination characteristics in laboratory conditions. The experiment was conducted based on completely randomized design with four replications in the fall of 2014 in the culturing and Proliferation laboratory of Zabol University. To create different levels of drought and salinity, polyethylene glycol 6000 and NaCl were used respectively .Drought treatments were included four levels (zero, -0/25, -0/41, -0/99 MPa) and five levels of salinity (zero, 50, 100, 150, 200 mM). Variance analysis results showed that drought and salinity stress significantly affected Alyssum seed germination characteristics (p

In order to evaluate and grouping wheat genotypes based on grain yield and important agronomic traits under drought stress, a field experiment was conducted with 43 wheat genotypes using a Randomized Complete Block design in three replication at Azad University, khorramabad, Iran in 2012-2013 cropping season. Evaluated traits were: day to maturity, day to pollination, grain filling rate, grain filling period, plant height, second internode length, peduncle length, peduncle extrusion, spike length, flag leaf length, spike weight, grain per spike, harvest index, thousand weight kernel, grain weight per spike, spike per square meter, biological yield, grain yield. Analysis of variance showed that there were significant difference among genotypes for most traits under drought stress. Factor analysis based on principle components and varimax rotation showed that 5 factors, yield, growth characteristics, spike index and factor affecting of grain characteristics explained 75.02% of data total variance under drought stress. Lastly cluster analysis based on UPGMA method was used for grouping genotyprs and genotypes were divided into 3 groups. The first group was the third place for grain yield. The second group was consist of 8 genotype and the maximum grain yield was compared to the other groups. 35, 18,19,24 genotypes showed the highest yield. The third group was in all related traits height the maximum amount.

Linum is the largest genus of the Linaceae family comprising nearly 2030 species. Flax (Linum usitassimum L.) is the third largest natural fiber crop in the world. In the present study, RAPD marker were employed to identify informative markers associated with traits such as plant high, weight of capsules per plant, weight branch, capsules number of branches, capsules of the main stem, stem length, branch length, number of branches, thousand seed weight, number of capsules per plant, seed yield, biological yield and harvest index in flax cultivars. Thirteen RAPD primers amplified 169 loci among 10 flax cultivars, with an average of 13 loci per primer. Polymorphic information content (PIC) ranged from 0.05 (OPA-03) to 0.29 (OPD03), with an average of 0.16. Cluster analysis based on molecular data assigned the genotypes into two groups, which coincided to geographic distribution. Cluster analysis result was confirmed by principal components analysis. Population structure analysis using model-based Bayesian confirmed the K=2, as the reliable value for the number of clusters. Stepwise regression analysis between molecular data as independent variables, and morphological data as dependent variables was performed to identify informative markers associated with the studied traits. Loci OPD-03 and OPD-05 were associated with both thousand seed weight and number of branches. Since all used RAPD loci except OPB-04 showed significant association with the studied traits, therefore, it is possible to use these primers along with morphological traits in flax breeding programs for identification of suitable parents to produce mapping populations and hybrid varieties.

One of the main objectives of citrus rootstock breeding is plants free of disease. In order to evaluate the effect of growth regulators on callus induction and regeneration of citrus rootstock, five citrus rootstocks were selected. Seeds were germinated after one month. Culture were incubated at 25 ° C and exposed to 16 hours per day. Explants were cultured on EME medium. Callus induction under factorial experiment with five citrus rootstock (Sour orange , Citrange, Citromelo, Poncirus, Volkameriana), concentration of NAA in three levels (0.5, 1, 1.5 mg) and concentration of Kin in three levels (3, 4, 6 mg) in a completely randomized design with three replications. The callus regeneration, five citrus rootstock with five hormonal treatment of factorial experiment in a completely randomized design with three replications was used. The results showed that the highest percentage of callus induction Sour orange of 0.5 mg/l NAA three mg/l Kin (25 %), the highest percentage of callus induction poncirus of one mg/l NAA three mg/l Kin (100%) and 1.5 mg/l NAA three mg/l Kin (100 %). highest percentage of callus induction for Citrange on the 0.5 mg/l NAA six mg/l Kin (91%) and Citromelo of one mg/l NAA three mg/l Kin (92%) and the highest percentage Volkameriana callus induction to 1.5 mg/l NAA three mg/l Kin (100 %). Frequency of callus induction with NAA and Kin (growth regulators)at concentrations of 1.5 and three mg/l. BA and NAA are known to be effective in regeneration. three mg/l Kin and 0.2 mg/l BA one mg/l NAA increased callus induction and regeneration, respectively.