جستجوی مقالات مرتبط با کلیدواژه « diversity » در نشریات گروه « زراعت »

World food security depends on two major cereal crops, wheat and rice. Where wheat is more important for its market value and production amount. Grain yield is determined by the achievement and distribution of assimilates in sink organs. Sink size in wheat depends on the number of spikelets per spike, grains number per spikelet as well as the grain weight. Hence, increasing spikelet number and sink size is one of the most important breeding targets of wheat. The object of the present study was investigation the genetic of spikes and spikelets in a divers bread wheat population for number of spiklets per spike.

In a bread wheat breeding program for transferring the awn character from Mahdavi to Roshan cultivar, in the second generation of the third backcross (BC3F2), a single plant with large spikes was observed. The mentioned genotype was purified after several selfing. The pure line was named as Roshan-D-01. After the fourth backcross of Roshan-D-01 with the recurrent parent (Roshan) and a selfing generation, a near isogenic population (BC4F2) was developed to study spike length. Spike length along with its related traits was studied in the current population at the research field of Shahid-Bahonar University of Kerman, during growing seasons of 2020-2021.

The spike length with the heritability of 0.61 and the response to selection of 14.03% showed a negative significant correlation with days to heading (r=-0.44**) and a positive significant correlation with other traits. Days to heading had a negative significant correlation with all studied traits at this research. This result showed the positive effect of early heading on spike related traits. Among studied traits, flag leaf area with general heritability of 0.53, positive significant correlation with spike length (r=0.60**), the highest Phenotypic and genotypic diversity (PCV=28.5 and GCV=20.69), showed the most response to selection (%R=25.45). The positive correlation between flag leaf area and spike related traits indicate the importance of flag leaf area in improving wheat grain yield. Distribution frequency graph of progenies for spike length, spikelet number per spike and grains number per spike showed that these traits have quantitative inheritance and follow the normal distribution. Transgressive segregation observed for studied traits and the presence of elite lines, in comparison with parents, in the current population allows the introduction of large spikes genotypes with high grains number per spike to develop high-yielding cultivars.

Due to high diversity and transgressive segregation observed in the present study, the current population can represent a rich source of spike morphology for use in wheat breeding programs aimed for increasing grain yield potential via increasing grain number. Negative correlation of days to heading with spike related traits indicates the positive effect of early heading on grain yield of bread wheat, especially under end season drought and heat stress conditions. Due to the high, positive and significant correlation between the spike length and flag leaf area, selection for larger flag leaf area could improve grain yield.

The genetic diversity of wild species associated with the early barley gene pool is crucial for exploitation in breeding programs. Barley (H. vulgar) and its ancestor (H. spontaneum) are excellent and economical model systems for genetic research, exploration and exploitation. In the study of the genetic diversity of 114 native barley populations collected from the west of the country, the EST-SSR molecular marker has been used to aim at the degree of genetic diversity of these native genotypes and evaluate the efficiency of these native genotypes and evaluate Is. There is genetic diversity in genotypes.

First, seeds were cultured in pots for DNA extraction. DNA extraction was performed by modified CTAB method for each genotype. Polymerase chain reaction (PCR) was performed in a volume of 20 μl. The PCR product was injected in 4% agarose gel with 1% TBE reaction buffer and Safe View dye to show the strips. In order to perform statistical analysis, the data were prepared in the form of a matrix and the parameters related to primers and populations were evaluated.

The number of amplified alleles varied from 2 to 4 alleles for markers and the studied primers reproduced a total of 40 alleles in the studied genotypes with an average of 2.85 per marker. The average percentage of polymorphisms for the studied primers was 96.42%. The content of polymorphic information (PIC) ranged from 0.397 to 0.189. The results showed that there is the highest level of diversity in the populations of Lorestan province and the lowest level of diversity in the populations of Kurdistan province. The dendrogram obtained from the cluster analysis of genotypes was divided into 14 groups, which according to the grouping of genetic diversity were partially adapted to the geographical distribution. Also, the results of the analysis to the original coordinates were somewhat consistent with the cluster analysis.

The results showed that there was good diversity among the studied populations. Also, suitable polymorphisms were observed among the primers. The primers GBM1221 with 3 alleles, GBM1461 with 3 alleles and SCSSR04163 with 4 alleles, which had the best polymorphism, are introduced as superior primers for use in future atmospheric research. The presence of high genetic diversity in natural populations of H. spontaneum wild barley indicates that the germplasm of this plant can be preserved in natural habitats. This diversity is also a valuable resource for identifying molecular markers informative for different phenotypic traits.

Grapes are a significant source of phenolic compounds, Genetic factors primarily determine anthocyanins, and in grapes, skin color is a critical and influential factor in the large germplasm of grapes. Since about 250 cultivars of 800-1000 grape cultivars are grown in Iran, studying anthocyanin compounds in the available germplasm resources is crucial. Therefore, this study was carried out to investigate the profile and diversity of different polyphenolic and anthocyanin compounds in some colored grapevine cultivars (V. vinifera L).

In this study the cultivars Flame, Crimson, Red Globe, Sahebi ghoochan, Ghare Shire, Sahebi Urmia, Syah Ghare Bagh, Rish baba, Flame seedless and Lale Bidane were investigated. The amount of phenol in the pulp was measured by the Folin-Ciocalteu method, and total flavonoids were measured by aluminum chloride calorimetry method. Total anthocyanin was measured with a spectrophotometer at 760 nm. The evaluation of the individual anthocyanin compounds was done by HPLC-DAD. Analysis of variance for all morphological traits was performed with the software IBM SPSS 26 using the one-way method ANOVA. The correlation among varieties, PCA analysis, and the scatter plot of the distribution according to PC1/PC2 were made with the statistical software SPSS. The distance values were calculated using the Euclidean method, and the dendrogram was generated using the UPGMA method of the NCSS statistical software (NCSS.12).

The percentage of total phenols, flavonoids, and anthocyanins in the berries of the studied cultivars were 48, 43, and 9, respectively. The results showed that the highest concentrations of total phenols were found in the cultivars “Crimson” (16.94 mg GAE/100 g), “Red Globe” (13.74 mg GAE/100 g), and “Flame” (13.58 mg GAE/100 g). The highest content of total flavonoids was found in “Flame” (36.47 mg100 g-1) and “Red Globe” (10.05 mg 100g-1), also the highest content of anthocyanins was found in “Ghare Shire”, “Syah Ghare Bagh”, “Lale Bidane” and “Sahebi Urmia” with 6.09, 6.59, 3.58 and 2.01 mg kg -1, respectively. Among the varieties studied, the lowest content of total anthocyanins, flavonoids, and phenol respectively was observed in “Flame” with 0.23 mg kg-1 and “Syah Ghare Bagh” with 5.8 mg/kg, and in “Sahebi ghoochan” with 2.88 mg kg-1. The composition of pelargonidin and its derivatives was not identified. The concentration of malvidin in “Flame” and “Red Globe” was trace and was not observed in “Sahebi Urmia” and “Lale Bidane”. The correlation results show that the highest positive and significant correlations were between delphinidin 6-acetyl glucoside and cyanidin 6-acetyl glucoside (r=0.99). Malvidin showed the highest correlation with delphinidin and petunidin. According to the dendrogram of cluster analysis of ten red cultivars for anthocyanins, they were divided into two main groups. The first group consisted of the two cultivars “Syah Ghare Bagh” and “Ghare Shire”, further away from the other eight cultivars of the second group.

The studied cultivars showed significant differences in the individual anthocyanin compounds and the amount of phenol, flavonoids, and total anthocyanins. According to the results, peonidin and malvidin had the highest concentrations in the studied cultivars; In “Syah Ghare Bagh”, the highest concentration of peonidin was found at 54.08 mg kg DW -1, and in “Ghare Shire” malvidin with 42.78 mg kg DW -1. In addition “Syah Ghare Bagh” and “Ghare Shire”' had the highest total anthocyanin concentration. Consequently, these genotypes were located in a separate group by distance from most cultivars based on cluster analyses.

The study of genetic diversity in crops is essential for breeding programs and conservation of heritage resources and is a key step in assessing the adaptation of the population to new environmental conditions and thus the selection of new cultivars. There are various methods for estimating genetic diversity in different plant species, including the use of morphological traits and DNA markers.

For this purpose, in this study, genetic diversity between 25 bread wheat accessions in terms of 23 agronomic traits and 20 SSR molecular markers was investigated. A field experiment was conducted in 2016-2017 in the form of a randomized complete block design with three replications in rainfed and irrigation at the end of the growing season conditions in the research farm and laboratories of the Faculty of Agriculture and Natural Resources of Razi University.

The results of analysis of variance showed that there was a significant difference between the accessions for most of the studied traits. Based on the results of cluster analysis, the accessions were divided into four groups. The results of comparing the mean and cluster analysis showed that accessions 2, 13, 6, 15, 18 and 10 were the best accessions based on agronomic characteristics, which can be suggested for breeding programs, and in contrast to accessions 3, 24, 11, 12 and 16 as the weakest accessions in terms of The studied agronomic traits were identified. In assessing the genetic diversity of the populations using 20 SSR markers, 16 primers with suitable polymorphisms were selected. The percentage of total polymorphism was estimated to be 93.75. XCFD168-2D, XGWM350-7D and XGWM136-1A primers with 100% polymorphism, maximum number of alleles, high amount of polymorphic information content indices, marker index, effective multiplex ratio index and resolving index due to the high proliferation of bands and the production of high polymorphic bands, they were introduced as the most suitable primers for wheat in subsequent studies. Molecular analysis of variance showed that the degree of diversity within the groups was greater than the diversity between the groups. The results of cluster analysis by UPGMA method based on Jaccard similarity coefficient led to the classification of 25 bread wheat accessions in four different groups, which showed high agreement with the results of analysis to the main coordinates, and finally accessions 1, 3 and 25 had the greatest genetic distance with accessions 13 , 7 and pioneer cultivars, so it is possible to suggest the selection of parents from these two groups for breeding programs.

Evaluation of agronomic characteristics showed that accessions 2, 13, 6, 15, 18 and 10 are superior accessions, among which, oxides of external and internal origin were observed. In evaluating the genetic diversity of the accessions, the primers XCFD168-2D, XGWM350-7D and XGWM136-1A were identified as the most suitable primers for wheat in subsequent studies. Markers with high polymorphism as well as markers and accessions with unique bands in the banding pattern are also of great value for breeding programs, for example, identifying genes useful for resistance to various biological and abiotic stresses in wheat and promoting its various cultivars.

 Abiotic stresses, especially drought, have a negative effect on crop growth and production. Plants display a variety of hysiological and biochemical responses both at the cellular and whole organism level upon sensing drought stress. Drought tolerance levels and antioxidant protection mechanisms were evaluated for 41 mutant genotypes seedlings (M3) induced of the ethyl methanesulfonate on Hashemi rice cultivar.

Drought was imposed in hydroponic culture with polyethylene glycol 6000 (PEG 6000) at the level of -10 bar using factorial experiment as completely randomized design. In this experiment the morphological characteristics of relative humidity content, electrolyte leakage, proline and antioxidant enzymes were investigated.

 All the studied genotypes showed apparent decreases in growth characteristics under drought stress. Based on different morpho- physiological parameters, two genotypes M29 and M122 were identified as promising drought tolerant mutant genotypes. They exhibited the maximum increase in root length without any significant changes in its root weight and root volume compared with the parent under stress and also showed better performance for various physiological parameters such as relative water content, cell membrane stability and proline content upon water stress under hydroponic conditions. Concomitantly, the activity of antioxidant enzymes catalase, peroxidase and ascorbate peroxidase in the drought-tolerant mutant genotypes increased markedly during drought stress, while decreased by drought stress in the drought sensitive mutant genotypes. Also, M31 and M106 mutant genotypes were introduced as the most susceptible genotype with minimum performance at stress level.

 In this study it was found, proline accumulation, increase of root biomass, increase of membrane stability and antioxidant enzymes such as POX, APX and CAT during water stress are contributing to drought tolerance conditions and could be used in screening for drought tolerance. The mutant genotypes identified in this study will be useful for further dissection of water stress tolerance in rice.

Lentil as a legume crop is one of the most important food crops in developing countries (Karimizadeh & Mohammadi, 2010). In most cases, the interaction between environment and genotype occurs, complicating selection for improved yield among genotypes (Sabaghpour et al., 2004). A cultivar or genotype is considered to be more adaptive or stable if it has a high mean yield but a low degree of fluctuation in yielding ability when grown in diverse environments (Finlay & Wilkinson, 1963). The response of different genotypes in different environments and thus the evaluation of genotype interaction in the environment are of particular importance to researchers in plant genetics and breeding, which can help plant breeders to evaluate genotypes more accurately and select the best one. The purpose of this study was to identify and introduce superior genotypes in terms of yield and yield stability among the lines obtained from preliminary yield test.

Sixteen advanced lentil genotypes along with the control genotypes i.e. Kimia and Gachsaran selected from the advanced yield trial of the 2012-13 cropping year were used as planting material in Gachsaran, Khorramabad and Ilam areas for three years (2013-2016) in a randomized complete block design with three replications. Analysis of variance was performed separately in each environment and then Bartlett test was used to evaluate the homogeneity of experimental errors. Then the combined analysis of variance was performed on seed yield. Stability analysis were performed using environmental variance (S2i), coefficient of variation (CVi), Shukla's variance (2i), Wrick equivalence (Wi), Plaisted statistic ( ), Plaisted and Peterson statistic ( ) and superiority index (Pi) and nonparametric methods, , , , TOP and mean of rank.

Simple analysis of variance showed genetic differences among the genotypes. The combined analysis of variance was performed after Bartlett test, which confirmed variance homogeneity of experimental errors (χ2 = 9.5; P = 0.33). The combined analysis of variance indicated the significant effects of genotype, year, location and interactions of year × location, genotype × location and genotype × year × location. The mean seed yield of genotypes showed that out of 18 studied genotypes, seven genotypes produced higher yields than the average yield of genotypes in the all environments (1566.39 kg.ha-1), so that the highest seed yield were seen in the genotypes 15 and 16, followed by genotypes 8, 12, 11, 5 and 2. Based on environmental variance (S2i), the genotypes 3, 7, 6 and 13 and based on the coefficient of environmental variation (CVi), the genotypes 3, 7, 6 and 15 were identified as stable genotypes. Plaisted and Plaisted and Peterson methods identified the genotypes 4, 9, 2, 10 and 3 as stable genotypes. Wrick equivalence and Shukla variance also introduced the genotypes 4, 9, 2, 10, 3 and 12 as stable genotypes. The Lin and Binns superiority index identified the genotypes 16, 8, 15, 12 and 11 as the most stable genotypes. The genotypes 4, 2, 3, 10 and 9 were the most stable genotypes based on nonparametric index. Based on the index, the genotypes 1, 2, 3, 4, 6, 7, 9, 10 and 18 and based on statistics, the genotypes 3, 4, 10, 9, 1, 7, 2 and 6 were stable genotypes. Based on Fox nonparametric index, the genotypes 16, 11, 2, 8, 12, 13 and 14 were stable genotypes. The genotypes 12, 2, 9, 16, 11, 8, 4 and 3 were more stable based on the total Kong rank. The principal component analysis to evaluate the relationship between seed yield and stability indices showed that seed yield had the highest correlation with MID, TOP and PI. Therefore, these three indices can be used as the best indices to identify superior genotypes in terms of seed yield and stability.

In general, the genotypes 2, 5, 8, 11, 12, 13, 15 and 16 gave higher average yield or equal to Gachsaran control seed yield and were also stable. The genotype 16 and 11 were the most stable genotypes based on MID, TOP and PI and also had the highest seed yield and could be candidates to be released as new cultivars.

Terminal heat stress has been recognized as the most widespread and detrimental type of heat stress in the world. In southern regions of Iran like Khuzestan, delay in planting date causes pollination and grain filling stages to be exposed to high temperatures, resulting in yield reduction. Developing heat tolerant cultivars is one of the ways to deal with heat stress. In this study, to identify resources of heat tolerance in wheat germplasm, a total of 203 bread wheat accessions with three control cultivars were planted in normal and delayed planting dates as an augmented experimental design in Ahwaz and the agronomic traits were evaluated. The results showed that almost all the evaluated traits were reduced in heat stress conditions compared to normal conditions. In both normal and heat stress conditions, some superior accessions were identified in terms of the studied traits compared to the control cultivars. In the biplot based on the principal components under heat stress conditions, 64 accessions along with control cultivars were located in the area of superior characteristics in terms of grain weight of five spikes, number of florets per spike, number of grains per spike, number of spikelets per spike, spike length and plant height. The studied accessions were divided into five groups by cluster analysis. The results showed a high diversity in the studied genetic material and the accessions superior to the control cultivars in terms of the studied traits were identified which can be used in future breeding programs.

Lentil is one of the most important legumes in rainfed and irrigated cultures, which is sensitive to weeds due to its low density and growth rate in early stages of growth. Therefore, lentil weed control is essential to prevent crop loss. Most studies of weed and crop competition have focused on mono-species competition, while generally there is not observed and the multispecies competition effects of weed populations are important. On the other hand, studies have shown that the presence of weeds in agricultural ecosystems is not always negative, even the presence of different weed species along the crop with increased diversity and nutrient cycling can lead to positive effects. Therefore, the knowledge of the effects of presence of different weed species on a field and the relationship between them is important. In this study, the relationships between weed communities in a lentil field and the effect of diversity indices on lentil yield were investigated. 

This experiment was conducted on one of rainfed lentil fields of the Agricultural and NaturalResources Campus of Razi University in Kermanshah during 2016 growing season. Systematic sampling was performed in two stages (before flowering and before physiologic maturity) to record weed density, height and dry matter as well as lentil grain yield. In addition, weed diversity and evenness indices (Shannon Weiner, Simpson, Smith and Wilson and Camargo Indices) were calculated using weed record data. The relationships between weeds and lentils were extracted by stepwise regression using SPSS statistical software V.20 and the spatial maps of weeds and lentil diversity were drawn using ArcGIS 10.2.2 software. 

The results of this study showed that a total of 45 weed species were recorded in the first stage of sampling and 28 species in the second stage of sampling. Recorded weed species in the studied lentil field were according to the important weed species of lentil farms in the west of Iran. So that, Brassicaceae, Asteraceae and Convolvulaceae were most frequented families, in addition, the most of the recorded species were broadleaves and the narrow leaves did not have much frequency. The results also showed that lentil yield was significantly affected by weed density and dry matter in the first and second stages of sampling, respectively. It has been stated that the high density of weeds during the vegetative period decreases biological yield and subsequently grain yield of the crops. Researchers also reported a negative correlation between yield and dry weight of weeds. The results of the effect of weed population evenness and diversity on lentil yield in the first sampling stage showed that Smith and Wilson evenness index and Simpson diversity index had a significant positive effect on lentil yield. In the study of, also there was a significant positive relationship between yield and weed diversity indices. However, in the second stage of sampling weed evenness and diversity did not have a significant effect on lentil yield. The study of spatial maps of lentil yield, Smith and Wilson evenness index and Simpson diversity index showed that the lentil yield was spatially correlated with weed evenness and diversity. In areas with low lentil yield, weed evenness and diversity were also low and in areas where lentil yield was high weed evenness and diversity were also high. This suggests that increased diversity and evenness in the fields can reduce the negative effects of weeds on crop yield. 

It can be concluded that the presence of weeds in the first and second stages of sampling led to decreased lentil yield, while the weed diversity and evenness had a positive and significant effect on lentil yield. In fact, by increasing the diversity and evenness of weeds and increasing the positive and negative interactions between them with other organisms, it seems that there was a positive effect on the lentil yield. In fact, increasing the weed diversity and evenness in farms could results in a fairer division of resources and less damages of some weed species on yield. The spatial distribution of the weed diversity and evenness, and its comparison with lentil yield showed a positive spatial relationship between increasing the weed diversity and evenness and lentil yield. Hence, increasing knowledge about weeds as well as their relationship with crops can reveal the positive aspects of weed presence in farms and, consequently, better weed management by increasing awareness in this field.

Nano-fertilizers due to the small amount of used fertilizer and the accuracy of plant acquisition are considered as a strategy to reduce inputs and achieve sustainability in agriculture production. In this experiment, the effects of nano iron and iron nitrate on the growth characteristics of wheat in different wheat and chickpea intercropping systems were investigated. The experiment was performed as split-split plot in randomized complete plot design with three replications in the research field of Campus of Agriculture and Natural Resources, University of Tehran, Karaj, Iran, in 2019. The main plots included five planting patterns (wheat monoculture, pea monoculture and three intercroppings of wheat:pea with 50:50, 70:50 and 90:50 ratio), sub-plots included three fertilizer treatments (control, nano-iron and iron nitrate) and sub-sub-plots included two fertilizer concentrations (1500 and 750 mg/L). The results showed that the 50:70 intercropping and concentration of 750 nano-iron had the highest iron use efficiency of wheat and in total, the iron use efficiency of wheat in 50:70 intercropping was higher than the other planting patterns. In contrast, the highest iron use efficiency of pea was observed in 50:90 intercropping and 750 concentration of iron nitrate. In all intercropping treatments, the fertilizer use efficiency by wheat and pea in nano-iron was higher than iron-nitrate. The highest wheat biomass and grain yield was obtained in monoculture + nano-iron (16371 and 5042 kg/ha, respectively) and monoculture + iron-nitrate (16062 and 5554, respectively), and the lowest wheat biomass and grain yield was related to 90:50 intercropping and iron-nitrate, but the highest pea biomass and grain yield in most fertilizer treatments at the concentrations of 750 and 1500 mg/L was related to iron-nitrate and nano-iron, respectively. The results of this experiment showed that in most of the planting pattern treatments and in all studied traits, the concentration of 750 mg/L iron nano-fertilizer was similar or even higher than the concentration of 1500 mg/L and therefore, a lower concentration of nano-fertilizer can be used and the consumption of fertilizer can be reduced.

Linum album Ky. Ex Boiss. is a perennial herb from Linaceae family, which have lignans that are anti-cancer compounds. Like other medicinal herbs the seeds of Linum album due to exposure to particular ecological conditions have dormancy, therefore, identification of ecophysiological factors that affecting on dormancy and determining the optimal conditions for seed germination and establishment of plants is essential to produce them. So in order to perform three experiments includes: investigation the effect of 15 different treatments on dormancy breaking (completely randomized design), germination (completely randomized design) and seedling establishment of different populations (randomized complete block design), seeds of these plants were collected in June 2014 from 13 sites. The results of this study showed that the effect of different treatments on germination percentage and other germination indices was significant at 1% level. In the control treatment, no germination occurred. The best results observed in 1000 ppm GA with 88.33 percent germination. The highest percentage of germination and seedling establishment observed in populations A4 (78.08%) and A6 (41.33%). To remove dormancy in Linum album it is proposed that we use combined GA treatment with stratification. Also, based on the indices studied, the use of populations A1 and A6 is recommended for improvement of breeding programs.

Iris Germanica has become the most well-known flower for landscape planning due to its colorful flowers, reproduction by creeping rhizomes, flat leaves, and a trio of flower parts, resistance to calcareous soils and adverse environmental conditions, and low watering requirements. Given the pharmaceutical-ornamental importance of I. germanica, this research was conducted to find new hybrids and their significant traits. Diversity and innovation in the field of flowers and plants are good, the world is presented with hundreds of colors and varieties and given the importance of I. germanica, the management to achieve hybridization between the new hybrid was performed.

Three genotypes of I. germanica with brown and blue (female parent) and yellow (paternal line) colors were selected for hybridization out of a total of 15 progenies and three parents to be evaluated in a randomized complete block design with three replications. The research was conducted in Ornamental Plants Research Center (OPRC) in Mahallat from 2014 to 2016. Quantitative traits included leaf width, peduncle length, peduncle thickness, flower diameter, outer petal width, inner petal length, inner petal width, bush length, flowering branch diameter, and crown diameter. The statistical analysis was conducted in the SAS and Excel software packages. According to the instructions of UPOV, 10 quantitative traits and some statistical parameters such as simple correlation coefficients, estimates of broad sense heritability, phonotypical and genetically coefficient of variations were measured.

Results showed significant (P≤0.01) differences between genotypes in all studied traits, indicating wide variations in traits except for the flower diameter. The correlation coefficients of quantitative traits among genotypes (parents and progenies) showed the most positive and significant correlation between the diameter of flowering branch and crown diameter, peduncle length, and inner length of petal. The highest broad sense heritability was related to the outer petal width (96.28), inner petal length (93.66), and bush length (93.40) and the lowest was related to peduncle length (42.58). The findings indicated that hybrid NIOP8 had the highest stem diameter. It was also superior in crown diameter, flower branch diameter, and peduncle diameter versus the other hybrids. The results indicated that hybridization has a significant effect on the traits.

The hybrids NIOP5 and NIOP8 outperformed the other hybrids and parents significantly in the length of inner petal, the width of the inner petal, and leaf width.

Summer savory (Satureja hortensis L.) is a valuable medicinal plant with useful properties and applications, has been recently used in the pharmaceutical industry due to its high level of carvacrol, thymol and rosmarinic acid. In this research, different accessions of this plant were collected from other countries and different regions of Iran. An experiment was conducted in 2019 year based on randomized complete block design to evaluate the morphological, phytochemical and essential oil traits of these accessions in Ardabil climatic condition. Analysis of variance showed that there were significant differences for the most studied traits among 20 accessions. The important traits such as plant diameter (19.78-45.29 cm2), shoot dry weight (0.08-2.05 g/p), 100-seed weight (0.021 to 0.126 g/p), and essential oil yields (0.23 to 2.21 g/h) were varied among accessions. The Ahvaz and Greece accession were the best in term of vegetative and phytochemical traits respectively. Maximum correlation was shown between bract number and seed length per plant (0.96). Cluster analysis, classified the accessions into five major groups. Factor analysis indicated that the five factors explained 77.78 of the variation among the accessions. The results of path analysis showed that the leaf area, leaf length/width, number of flowers in inflorescence, phenolic content and shoot dry weight had effect in essential oil yield of accessions and phenolic content had the highest direct and positive effect (0.8). The results suggested that there was a considerable genetic variation among S. hortensis accessions.

Given the increasing demand for food supply due to human population growth and the limited arable land, the role of plant breeding in increasing crop production is evident. Wheat (Triticum spp.) is known as an important food source in the world because of its adaptation to different environments. Triticale (X. Triticosecale Witmack) has high adaptability to biotic and abiotic stresses and is able to produce efficiently even in poorly fertilized soils and low input farming systems. Heterosis is a natural phenomenon that depends on the species and genetic variation and is called the increase in hybrid vigor of parents, which can be explored to increase crop production. Since the exploitation of heterosis is promising in wheat, the employment of putative hybrids for sustainable food supply has potentially increased. Hence, the aim of this study was to estimate heterosis and to evaluate the coefficients of phenotypic and genetic variation as well as heritability estimates.

A total of 79 genotypes including 19 common wheat, 3 durum wheat, 4 triticale along with their 53 F1 hybrids were used, in this study. Morphological traits including yield and yield components viz. plant height, number of spike per plant, number of grains per spike, grain weight per spike, 1000 grain weight and grain yield per plant were measured. The heterosis estimates in the studied hybrids were calculated based on the mid-parent and better-parent. After analysis of variance, coefficients of phenotypic variation, coefficients of genetic variation and general heritability were estimated.

The results of analysis of variance showed significant differences among the genotypes for the studied traits. Mean squares of parents versus hybrids were significant for all traits, indicating heterosis in the studied traits. F1 hybrid derived from Long Spike 2 × Sirvan cross had the lowest heterosis compared to the mid-parent and superior parent for plant height. The highest percentage of heterosis for grain yield per plant belonged to the hybrid derived from the cross between Long spike 5 × Roshan. The estimated heterosis for grain yield based on mid-parent value showed a range of 25.34 to –25.41, indicating the high genetic diversity of the parents used to produce the 53 F1 hybrids studied.

Given the genetic diversity observed in this study indicating heterosis in the studied traits as well as high heritability in the traits, the diversity can be explored either by hybrid breeding strategy or advancing segregating generations toward developing new cultivars.

This study was conducted to investigate the genetic diversity of bread wheat, durum wheat and triticale using agronomic and physiological traits. Genetic diversity of 24 genotypes was evaluated in 2 locations (Research Farm of College of Agriculture, Isfahan University of Technology, located at Lavark, Najaf-Abad and Asheghabad farm), Isfahan, Iran, using a randomized complete block design with two replications in each location during 2016-217. In this study 20 bread wheat, 2 durum wheat and 2 triticale genotypes were examined. Results of analysis of variance showed that the effect of genotype for all traits, except for maximum fluorescence, was significant. In the studied traits, phenotypic and genetic variation coefficients did not considerably differ for most of the traits, indicating the prominent genetic effects on these traits. The correlation coefficients showed that there is a positive and significant correlation between grain yield with number of spike per plant, biological yield and harvest index. Factor analysis revealed four hidden factors that justified a total of 66.47 percent of the variation in the experimental materials. These factors were introduced as maturity period, grain, yield and photosynthesis, respectively. The cluster analysis of genotypes based on the studied traits divided the genotypes into four groups, some of which have desirable traits and are relevant for the breeding program.

Drought is the abiotic stress to decrease yield potential. To screen and identify drought tolerant genotypes of bread wheat landraces, was studied in a randomized complete block design with three replications with two levels of stress (stress and non-stress environments) and 25 bread wheat genotypes, at the Razi University of Kermanshah in 2017-2018. Results of analysis of variance and mean comparison of morphological, physiological and biochemical traits showed that effect of genotype was significant for most of the traits under stress. Correlation coefficients showed a positive and significant result between yield with thousand seed weight and biological yield in both stress and non-stress conditions. Analysis of variance and mean comparisons showed that genotype No. 10 was superior under both stress and non-stress conditions. The results of correlation between drought stress indices showed that STI, MRP and biological yield were positively and significantly correlated with grain yield under both stress and non-stress conditions. Ranking of genotypes, based on sum of ranks, mean ranks and standard deviation of ranks, showed that genotypes 10, 15 and 18 were best rank and recognized as superior drought resistant genotypes, while genotypes 4, 16, and 22 were identified susceptible. Factor analysis in stress environment explained 80.55% of the variance by four main factors. Ward's cluster analysis under stress condition divided the genotypes into four groups. Grouping of genotypes were somewhat different due to different responses of bread wheat genotypes to water deficit stress and their differences in susceptibilies or relative resistancese.

Research, selection and protection of landraces in most countries of the world are very important and considered as one of the most important and significant issues in plant breeding programs. Despite the recent progresses in plant breeding programs, using of landraces is still particularly important, especially in the self pollinated crops. In breeding programs, the existence of favorable variation in the population is essential and without variation, the progress and development of breeding programs will be slow process. Lentil seeds are a major role in feed and food security for millions of people, especially among the low income Asian population, because of protein content and cheap price. The lentil plant has also played an important role as a rotation crop for increasing the fertility of soils and it has been special attention for agronomists and researchers in case of sustainable agriculture. Food legume cultivation traditionally is common in Iran. Except in the northern wet areas, lentil cultivated in most parts of Iran. Its cultivation areas is 150-200 thousand hectares and ranked as second important food legume in the drylands area. There are little studies about evaluation and purification of lentil landraces in Iran. Kouhin region in Ghazvin province with about 12000 hectare lentil cultivated area is one of the most favorite regions of cultivation and production of lentil in Iran. Green Koohin lentil landrace has good quality and nutritional value and is famous for consumers in the country.

This study was performed to evaluate a lentil landrace originated from Kouhin region in Ghazvin province. The experiment was conducted for two consecutive seasons during 2010-12 under field condition in Maragheh Dryland Agricultural Research Station (Latitude 37°15′ N, Longitude 46°15΄ E, and Altitude 1720 meter above sea level). In spring 2011 and 2012, the seeds of 120 pure lines (individual plants that were selected from Kouhin landrace), planted at farm under rainfed condition and eight traits (No. of days to flowering, No. of days to maturity, grain filling period, plant height, 100 seed weight, seed yield, biological yield and harvest index) were noted. Statistical parameters (maximum, minimum, mean, standard division and phenotypic coefficient of variance) were calculated for noted characteristics. After standardization of data, distance modulus squared Euclidean distance cluster analysis was done in Ward method.

Analysis of variance results showed that there were significant differences between the genotypes in all studied traits except in the case of biomass yield and harvest index. These results indicating the existence of genetic diversity among the pure lines extracted from the Kouhin lentil landrace. Results of estimating descriptive statistics of studied characteristics in the 120 pure lines showed that, the grain yield among the studied characteristics in two years means had the highest diversity. In the first year, the minimum and maximum grain yield (160 and 1420 Kg/ha) belonged to genotypes No. 98 and No. 14, respectively. In the second year grain yield was also varied from 170 Kg/ha (genotype no. 113) to 980 Kg/ha (genotype no. 73). This result indicated the existence of high performance potential within the Kouhin landrace and in order to improve the grain yield of population, identification and purification of the high yielding genotypes from population recommended. Among the studied traits the minimum diversity belonged to number of days from plating till flowering and maturity. Regarding to this point that the Kouhin landrace was cultivated from long time ago by farmers, natural factors such as day length, existence of drought stress (especially after flowering because of dryland farming) removed the late genotypes and caused relatively hemozigosity on these two traits in the Kouhin population. Results of clustering showed that genotypes were categorized in six groups. Twenty five genotypes were in the fifth group that their grain yield (527.6±126.8 Kg/ha) was higher than other groups.

The results of this study showed that it could be improved the grain yield and other characterstics of Kouhin population under drylands condition by selection of pure lines. Also it is possible to use the existing potentialities in Kouhin landrace (genetic diversity) in the lentil breeding programs under dryland condition. Conclusion of the results showed that there is suit variation in Kouhin lentil landrace and it could be used as a precious resource for lentil breeding programs under dryland of Iran.