جستجوی مقالات مرتبط با کلیدواژه "تجزیه به مولفه های اصلی" در نشریات گروه "باغبانی"

Cantaloupe is one of the most important vegetable crops in Iran. In recent years, due to some problems, such as low sweetness and fruit yield, plant death diseases, and the indiscriminate introduction of foreign commercial hybrid cultivars, the genetic resources of this product have been severely eroded. Therefore, in this research the crossing of important local cultivars such as Saveh and Niagara with the commercial and selected F1 cultivar Galia was considered to combine the best traits and select the best genotypes of the F2 generation by pedigree selection method and continuity of generations. This experiment was carried out in the Faculty of Agricultural Technology (Aboureyhan Campus) University of Tehran research farm. The selection of the best genotypes was done in three stages (natural screening in the field for disease, virus, and mite resistance, evaluation based on qualitative traits in the laboratory, and final selection of genotypes based on the results obtained from multivariate analysis of quantitative traits). The results showed that in Niagara × Gallia (NGF2) population, general heritability was high for all the evaluated traits except the fruit shape index. In the Saveh × Gallia (SGF2) population flesh thickness, soluble solids and fruit harvest date had the highest heritability. The results showed that the traits included in the stepwise regression model accounted for 90.3 and 80.3 percent of the total changes related to fruit weight in NGF2 and SGF2 populations, respectively. Based on the principal component analysis, in NGF2 and SGF2 populations, two principal components explained 71.88 and 71.31% of the data variance, respectively. Based on the results of the bi-plot analysis, 30 NGF2 and 53 SGF2 genotypes were selected, and cultivated in order to continue generations and reach pure parental lines in the F3 generation.

 Tomato is a product with a wide range of genotypes with different yields and selection based on this trait and its components can accelerate the breeding programs of this plant. The most important goals of tomato breeders have been to increase yield, disease resistance, early maturity, and improve the quality characteristics of the fruit. Therefore, awareness of genetic diversity in the population is an important step in plant breeding, and to achieve this goal, the studied genotypes must first be identified in terms of genetic potential and favorable agronomic traits. The usual approach for describing and evaluating populations requires cultivating sample populations and evaluating their morphological and agronomic characteristics. In this regard, multivariate statistical methods play an important role in studying genetic diversity and selecting appropriate parents. Unfortunately, the tomato cultivars used in Iran are often not at the favorable level in terms of important traits such as the number of days to fruit ripening, fruit weight, fruit yield, fruit length, and width, and few studies have been done on these traits. Therefore, this study was conducted to investigate the morphological diversity, evaluate the yield and its components among some imported tomato lines using analysis of variance, cluster analysis, and principal component analysis.

 This study was performed in Sari University of Agricultural Sciences and Natural Resources, Mazandaran, Iran in 2020. The plant material included 24 tomato lines imported from the Canadian Plant Gene Bank and one check variety. The experimental design used for morphological analysis was a randomized complete block design with three replications. Evaluated characteristics were included of the number of days to first flowering, number of days from germination to first fruit coloring (early ripening), plant height (cm), number of fruits per plant, average fruit weight per plant (g), plant yield (g), length and width of the fruit (cm). After measuring the characteristics at the farm and recording the data, analysis of variance was performed to examine the diversity between lines in terms of the studied variables, and Duncan test was used to compare the means and SAS software was used to test the correlation coefficients of the variables. Cluster analysis for grouping of tomato lines was performed based on the mean of the main data of standardized traits, which was determined by Euclidean distance to determine the distance between the lines, and the UPGMA method was used to merge the clusters. Principal component analysis was performed based on the mean of the main data of morphological traits.

 The results of the analysis of variance showed that there was a significant difference between all lines in terms of the studied characters. Also, principal component analysis based on morphological traits showed that the first two main components accounted for 75% of the total phenotypic variation in the data and the number of days from germination to first fruit coloring (-0.606), the number of days to first flowering (-0.516), fruit weight per plant (0.492), fruit width (0.480), fruit length (0.472), plant height (-0.445), fruit yield per plant (0.395) and the number of fruits per plant (-0.367) had the highest contribution in yield changes. Therefore, these variables might be taken into consideration for effective selection of parents for hybridization programs for broadening the genetic base in the population as well as to develop elite lines or F1 hybrids. UPGMA cluster analysis also divided the studied lines into nine groups. Group IX lines were in good condition in terms of yield traits and components, group VIII lines in terms of maturity and flowering, and group IV lines in terms of fruit number per plant. And the lines in groups I and V were in moderate condition for all traits. According to these results, the cross of the lines in the more distant groups can produce hybrids with high diversity and maximum heterosis.

 According to the main purpose of this study, which was to evaluate the yield and its components and according to the analysis performed, lines 8, 11, and 17 due to showing the least number of days to flowering and early, lines 10 and 14 due to having the highest yield, the highest fruit weight, and highest fruit length and width and lines 2, 9, 15, 21, and 24 due to having the highest number of fruits per plant and the favorable height are also recommended for use in tomato breeding programs.

Salinity tolerant of 24 lentil genotypes was investigated in a split-plot based on a randomized complete blocks design with three replications. Salinity levels (0.5, 12, and 16 dS m-1) were arranged as the main plot and lentil genotypes as the subplot. Results indicated that salinity levels of 12 and 16 dS m-1 reduced the survival percentage of all genotypes compared to control. MLC57, MLC73, MLC94, MLC104, and MLC108 genotypes were not able to tolerate the 16 dS m-1 salinity level. Morphological traits were affected by salinity stress as plant height, number of branches per plant, dry weight, and leaf survival percentage in most genotypes were decreased. Compared to control, the lowest reductions of plant height, number of branches per plant, plant dry weight, and leaf survival percentage were observed at salinity level of 16 dS m-1 in MLC13, MLC120, MLC4, and MLC12 genotypes, respectively. Also the lowest increase in Na+ (5.5 times) and the highest increase in Ca2+ (4 times) were observed at salinity level of 16 dS m-1, in MLC108 and MLC78, respectively. In other words, these genotypes were able to reduce the adverse effects of increased NaCl in higher salinity levels. Principal component analysis (PCA) showed that all genotypes of the first group (MLC6, MLC12, MLC26, MLC117, MLC120, and MLC178) were superior for most traits as compared to the total mean. Generally, it could be concluded that this group of genotypes has a better survival percentage and growth characteristics in salinity conditions, which may be used to select salinity tolerant lentil genotypes in subsequent studies.

Witches’ broom disease of lime (WBDL), caused by ‘Candidatus Phytoplasma aurantifolia’, is major limiting factor for Mexican lime (Citrus aurantifolia Swingle) production in southern Iran. In this investigation, leaf nutrient profiling of the healthy and infected rooted Mexican lime during WBDL progression (90-330 days) as well as to distinguish the infected from the healthy Mexican limes under greenhouse condition. For this aim, the healthy and infected plants were sampled 90, 150, 210, 270 and 330 days after inoculation with phytoplasma and leaf nutrient concentrations including nitrogen, phosphorus, potassium, calcium, magnesium, boron, iron, manganese, zinc and copper were measured during WBDL progression. The results showed phytoplasmal infection mostly caused to a marked decrease in the concentration of nitrogen, calcium, boron, manganese, and significant increase in phosphorus, magnesium, potassium, iron, and zinc in the infected leaves. In Mexican lime leaves, copper concentration did not significantly change after inoculation with phytoplasma with respect to the healthy plants. In addition, the principal components analysis (PCA) based on the concentration of nutrients could not distinction infected and healthy plants in the early stages of sampling (before the appearance of symptoms), but PCA revealed a clear distinction between the leaf nutritional profiles of healthy and infected plants after the appearance of symptoms during the progression of WBDL. In conclusion, this study provides new insights into the lime response to phytoplasma infection during the progression of WBDL and it can be useful in adopting strategies to improve and increase the economic efficiency of trees infected with WBDL.

It is important to study the morphological diversity of native almond genotypes with the aim of selecting and introducing new cultivars. In this study, 30 native collected genotypes and six commercial cultivars of almond were evaluated in terms of 22 quantitative and qualitative traits of nut and kernel. High diversity was observed for nut weight, shell color, shell hardness, shell opening, kernel taste, and kernel percentage among evaluated genotypes. Cluster analysis based on index traits divided these genotypes into five groups. The genotypes ALC203 and ALC413 and the cultivars Non-pariel, Yalda, and Manaqha which were located in the second cluster, had thin shell with high percentage of kernel that are important for nut consumption. In principal components analysis based on the average of 10 index traits, the first three main components explained a total of 80.75 % of the diversity of traits. In the first main component, nut weight, shell thickness and shell hardness and in the second main component, nut and kernel size had the major part in the separation of genotypes. Shell hardness had significant positive correlation with shell thickness and nut weight. Kernel percentage had significant negative correlation with shell thickness and its hardness but showed positive correlation with shell opening. These results are useful for selecting new promising genotypes of almond.

This study was performed to evaluate and compare quantitative and qualitative forage yield of Iranian and foreign alfalfa cultivars and ecotypes as well as correlation between traits and genetic variation among them. Therefore, 12 cultivars and ecotypes of alfalfa were evaluated in a randomized complete block design with three replications at research field of Islamic Azad University, Karaj, Iran for two years 2016-2017. The results showed significant differences for forage yield, agronomic traits and forage quality. Significant interactions of year × ecotype was observed for fresh forage yield and total dry forage yields and also plant height. Among the studied ecotypes, the ecotypes Mohajeran, Malekkandi and Ghahavand indicted the highest fresh and dry forage yield. The results of simple correlation showed that the highest positive and significant correlation between fresh and dry forage yield (0.98). Principal component analysis showed that 74% of the total variance was justified by the first two components. Results of cluster analysis divided the studied genotypes into three groups. In the first group, the ecotypes of Ghahavand, Mohajeran and Malekandi were considered to be the best in terms of forage yield, while in the second group they were Chaleshtar, Legend and Sequel were best for forage quality. In the third group, the other cultivars were classified as having average forage yield and quality

Witches’ broom disease of lime (WBDL), caused by ‘Candidatus Phytoplasma aurantifolia’, is major limiting factor for Mexican lime (Citrus aurantifolia Swingle) production in southern Iran. In this investigation, biochemical composition profiling of the healthy and infected rooted Mexican lime wasmonitored during WBDL progression (90-330 days) as well as to distinguish infected from healthy Mexican limes under greenhouse conditions. For this aim, stem cuttings is taken from healthy Mexican lime. After three months, half of Mexican lime cutting were inoculated by bark-grafting from WBDL-affected Mexican. Six healthy and infected plants were sampled 90, 150, 210, 270 and 330 days after inoculation with Phytoplasma. Pigments, total phenol, antioxidant capacity, soluble carbohydrate and starch content in leaves were measured. Results showed Phytoplasmal infection caused growth inhibition and reduced stem and root dry mater. Moreover, infection mostly caused to a marked decrease in pigments and significantly increased soluble carbohydrates and starch. In Mexican lime leaves, phenol contents and antioxidant capacity were increased after inoculation with Phytoplasma. In addition, the principal components analysis (PCA) revealed a clear distinction between the leaf biochemical profiles of healthy and infected plants during the progression of WBDL. In conclusion, this study provides new insights into the lime response to phytoplasma infection during the progression of WBDL. Finally, we showed that healthy plants can be isolated from infected plants using biochemical profiles.

In order to investigate the genetic diversity of 65 lines of pepper, collected from different regions of the country and also from China and the International Research Center for Vegetables (AVRDC), a randomized complete block design with 3 replications was done. Results of analysis of variance showed a significant difference among genotypes at 1% probability level for all traits. Based on the mean comparison of different traits using Tukey's method at 5% probability level, genotypes 3095, 0013 and 26-6 were better in terms of yield and characteristics associated with marketable products. To determine the genetic distance and grouping of genotypes, factor and cluster analysis performed. To understand the internal relations of traits and to determine the group of variables with the highest correlation, factor analysis performed using principal component analysis were through varimax rotation. In these analysis, four independent factors justified 74.7% of the variation. Cluster analysis was done using Ward method, and the lines were gathered into six different groups. So that, this grouping was associated with geographic distribution of lines and some of morphological traits that associated with marketability. Results of stepwise regression showed that three traits of stem diameter, stem length and number of fruits per plant had the greatest effect on fruit yield. To evaluate the direct and indirect effects of these traits on fruit yield, Path analysis performed. Results showed that the three mentioned traits had direct effect and indirect effect of these traits was very low. Given that in this experiment lines under study showed significant differences in terms of genetic variability for traits under evaluation. It was concluded in order to benefit from heterosis, selection of superior genotypes with greater genetic distance from each other can be useful in pepper hybrid variety production.

In order to study of the genetic variation among some olive cultivars and of identification the best ones, 30 cultivars of Iranian and foreign olive genotypes that cultivated in olive research station of Tarom, Zanjan were evaluated and 36 quantitative and qualitative characters were assessed in this procedure. Variance analysis results illustrated that there was significant difference among examined cultivars for all characters and showed high genetic variation in all the studied cultivars. Results of simple correlation analysis showed the existence of significant positive and negative correlation among some important characters. Stepwise regression showed that yield more than other traits, depended on flower properties, percentage of complete flower and amount of oil in wet matter, while the percent of oil in wet matter depended on fruit phenological variables like the time of fruit color change and fruit maturity. Factors analysis represented that 10 component accounted over 90% of total variances. Pomologic and phenologic characteristics of fruit, characteristics of flower, yield, fruit moisture, amount of oil in dry matter, amount of oil in wet matter and leaf morphologic properties were constituted as main factors. Cluster analyses in the distance of 13 were divided cultivars into 11 clusters. According to high genetic variation among the cultivars, hybridization can be effective to improve yield, amount of oil in wet matter and production of new varieties.

Mango is one of the most important tropical fruits also known as the king of fruits. In this study, the relations among 19 morphological traits of leaves and fruits corresponding to 27 mango genotypes were evaluated. Based on the results of variance analysis, there was a significant difference between genotypes in most traits. Therefore, these genotypes had diversity in studied traits. According to the results, the Sindri and Nargil genotypes had the highest and lowest number of fruits per tree (with an average of 847 and 340 pcs, respecively). Moreover, Sindri and Shahani 2 genotypes showed the highest yield per tree (with an average of 261 and 240,Kg respecively). Based on the results of the correlation coefficient, these traits showed high and significant correlation. The highest and most significant correlation (0.75) was observed between the number of fruits and yield. According to the results of cluster analysis, these genotypes could be divided into four major groups. This investigation indicates there is a high variation among mango samples which can be attributed to the sexual reproduction by seeds, its cross pollination as well as climatic variation in Iran. Since Sindri and Shahani 2 imported cultivars had the highest number of fruits, weight of fruit and yield, the Shahani 2 genotype could be suggested as an appropriate genotype in future studies, breeding programs and mango cultivation in these areas.

In this study, 21 pomegranate genotypes were collected from Lorestan province, and evaluated using morphological and biochemical characteristics. Results of variance analysis showed statistic significant differences between genotypes, except for percent of skin, pH, and soluble solids traits. The amount of variation in total genotypes, showed the highest coefficient of variation was 50.11, 46.06 and 32.22% for vitamin C, weight of fruit and amount of acid, respectively. Principal components analysis showed that four main factors could have denoted 98.91% of the total variation. Distribution of genotypes using Principal components analysis was performed and plot distribution of genotypes showed that A7 (‘Souze shine Shah Taj Kutah’) genotype had the highest fruit weight, the two main components of the first and second highest coefficient was positive. Traits such as single berry weight, the total weight of the skin, weight of 10 seeds, leaf length to width ratio, the percentage of skin in the first component (PC1) and crown length, acidity, leaf and fruit in the second component (PC2), was grouped respectively. Cluster analysis of genotypes was performed by Ward method and 21 genotypes in Euclidian distance 5 were classified into six clusters that genotypes collected from a region were located in different clusters. In this study, important factors in genotype grouping were weight and figure of fruit. These result obtained due to differences between genotypes in each region and no relation betwen genetic distance with geographical distance was found.

In this study, the growth and flowering characteristics of 10 accessions of Salix aegyptiaca L. grown in the collection of Kurdistan agricultural research center were assessed. The experiment was run in a randomized complete block design (RCBD) with three replications. The analysis of variances showed significant differences (P≤ 0.01) among accessions for characteristics such as tree height, collar diameter, catkin length, catkin length/width ratio, leaf length, leaf width, leaf length/width ratio, leaf area, petiole length and significant differences (P≤ 0.05) among accessions for angle of branches with trunk, length of annual shoot, catkin length width. Based on the results of correlation coefficients, there were significant positive correlations between leaf area and flowering characteristics (catkin length, width, fresh and dry weight). Moreover, there were significant negative correlations between tree height and catkin length and fresh weight. Cluster analysis of studied traits grouped accessions into three clusters. To determine the superior accessions, principal component analysis was used. Bi-plot was made based on the first two components which covered 70 percent of total variance and showed the accessions of K2, K3 and K6 were superior and could be recommended for landscape designing and breeding programs.

To determine the quantitative and qualitative characteristics of six dragonhead (Dracocephalum moldavica L.) populations at six habitats, an experiment was conducted as completely randomized design with three replications (at intervals of 500 to 1000 m) in 2013. Each dragonhead population belongs to a habitat including Salmas, Urmia, Khoy, Maragheh, Piranshahr and Tabriz. The szk-1cultivar, as a control treatment, was planted in the Research Field of Payam Noor University (PNU) in Marand. In each habitat, flowering branches of dragonhead were collected in full flowering stage. In this study, some traits such as plant height, number of branches, number of flowering branches, essential oil content, nitrogen, phosphorus, and potassium in shoot as well as chlorophyll contents (a, b and total), carotenoids, flavonoids and anthocyanins were measured. According to the obtained results, the effect of habitat was significant on plant height, number of branches, essential oil, the amount of nitrogen, phosphorus, chlorophyll and flavonoids at 5% level as well as on number of flowering branches and anthocyanin amount at 1% level. Results showed that the highest plant height and nitrogen, phosphorus, chlorophyll, carotenoids and essential oil contents were obtained from Salmas population. The Szk-1 cultivar produced the highest number of lateral and flowering branches and total flavonoids in Marand. In general, Salmas population had the best growth characteristics and qualitative traits. Therefore, this population could be used to produce varieties with desirable agronomic properties.

Introduction Apricot (Prunus armeniaca L.) has special position in Iran fruit culture industry. In terms of cultivation and producing, Iran is one of the major countries in the world but in terms of export Iran is ranked 23. For this reason, research on necessities of fruit culture industries and access to new cultivars by breeding project is required. Obviously, paying attention to quality and quantity of products and using of local germplasm that known completely, played a significant role in this project. Apricot with genomic feature 2n=16, has extensive diversity due to sexual propagation and cultivation in different areas. Central Asia and Caucasian groups of apricot that involving Iranian and Turkish cultivars, have greatest phenotypic variations, while European group including cultivars that cultivated in North America, Australia and South Africa have the lowest diversity. Climate adaptation, increasing of fruits quality, self-compatibility and resistance to diseases are the most important goals of apricot breeding. Of course, the quality of fruits depends on sugar and acid balance and special aroma. One of the important targets of apricot breeding is introduce and develop of cultivars that can be cultivated in extensive areas. Target of recent study is primary evaluating of morphological and pomological traits of some cultivar and genotypes of apricot grown in Zanjan province. In order to introduce the cultivars that produces fruit with high quality and complete scientific researches to selection of ideal cultivars in this region for future.
Method and material: This research carried out on four cultivars (Badami, Daneshkadeh, Shekarpareh, Shahroodi) and two genotypes (C and D) and was conducted in a completely randomize design with three replications. Evaluating of tree, branch, leaf, flower and some fruit traits performed based on existing descriptor. For determining some important pomological traits, fruits harvested in commercial time and transferred to laboratory. For measuring total soluble solid (TSS), refractometer (model: ATAGO-N1) was used. To determinetitratableacidity (TA) titration with 0.1 N NaOH method and for measuring pH content, pH-meter (model: JENWAY 3020) was used. The weight of fruit and stone was measured with digital balance. Flesh fresh weight also was determined with digital balance and flesh dry weight was measured after 72 hours dried in oven. Finally flesh firmness was determined with presser meter (model: OSK 1618). For evaluating fruit set percent, flowers of some branches in every cultivar was numerated then primary and final fruit set percent was calculated after 10 and 30 days, respectively. Data analysis was done with SAS 9.1, SPSS 20 and Statistica 10 software.
The results of qualitative data that analysis with non- parametric (Kruskal-wallis) method showed significant differences among some genotypes and cultivars. In terms of corebitternes strait genotype D showed significant differences with other cultivar and genotypes. Due to this trait, genotype D is suitable for use as rootstockbecause the genotypes with kernel are suitable for cultivation in lime and semi dry soil and also are resistant nematode. In terms of blooming time, genotype D (late blooming)had significant differences with genotype C, Badami and Shahroodi cultivars. Because of this trait, genotype D is resistance to late spring chilling injury. Based on trees growth habit, genotype C (long growth habit) showed significant differences with Shekarpareh cultivar (widespread growth habit). In terms of flower bud distributions genotype C (blooming on annual branches) showed significant differences with genotype D and Daneshkadeh cultivar (blooming on spurs). According to these traits genotype C is suitable for dense cultivation orchards and need to prune every year like peach. Results of correlations among traits showed that TA has negative significant correlations with flesh dry weight, TSS/TA ratio and flesh weight/stone weight ratio. During fruit ripening TA rates was decreased and TSS rates were increased, so during of TSS increasing as one of the non-structural components of dry matter, flesh dry weight increasing simultaneously. Positive correlations between flesh dry weight and TSS/TA ratio indicate that cultivars with big fruits have high dry matter, so they are sweeter than other cultivars. Also aprincipal component analysis (PCA) was used to determine the number of important factors that influenced on morphological identification. The results of PCA showed that total variance (90.2%) is justified by two factors. The first factor (73.05%) included all fruit traits, leaf length and first and second fruit set percent. The second factor (17.21%) contained flower diameter, core length and juice percent. Consider to this analysis, Shahrodi, Daneshkadeh and Shekarpareh cultivars were settled near each other but Badami cultivar, Cand D genotypes were placed separately.
According to the results, high diversity was observed among genotypes and cultivars. This diversity provides suitable genetic resources for breeding works. Results of this study showed that Daneshkadeh cultivar has the biggest fruits and Shahroodi cultivar has the most rates of TSS and flesh firmness, so this cultivar has long storage life. Finally, the Shekarpareh cultivar showed the most flesh dry weight and flesh weight/stone weight ratio, so this cultivar is suitable for processing.

In order to study of genetic diversity and similarity among four native olive cultivars including ‘Mari’, ‘Zard’, ‘Shengeh’ and ‘Rowghani’, these cultivars were evaluated in five regions including Ali abad, Gilvan, Tarom, Manjil and Jamal abad at 2012-2013. There was a significant difference among studied individuals. The correlation coefficient analysis among studied traits showed that there was a good correlation among quantitative traits such as flesh, fruit weight, fruit shape and stone shape, while the correlation among qualitative traits was low. The results of PCA earned three components which accounted 91.93 percent. The scatter diagram of individuals based on two first components showed a good distinction for individuals. The cluster analysis separated six distinct groups in which Mari population formed three neighbour groups. ‘Zard’ population also showed high homogeneity, while ‘Shengeh’ showed the most dispersion however it was closely similarity to ‘Rowghani’ population.

This experiment was conducted to investigate the genetic diversity، relationship between morphological، agronomic and qualitative traits and to identify components of forage yield using some multivariate statistical methods in local sainfoin populations. The experiment was conducted as randomized complete block design with three replications in Agricultural and Natural Resources Research Center of West Azerbaijan. Results indicated that correlation coefficients of forage yield with number of branches per main stem، number of leave and number of stem were significantly positive but with harvest index leaf and degree day emergence was significantly negative. Forage yield had no correlation with plant height but plant height was correlated with number of leave. Principal component analysis revealed six component which justified more than 76 percent of the total variation، and classified as “Yield”، “Dry weight”، “Plant size”، “Harvest index leaf”، “Morphological-phenological traits” and “Flowering rate”، respectively. On the basis of stepwise regression analysis، number of stem، plant height and number of leave justified the majority of hay yield variation. Hence، these characters could be use for selecting high yield cultivars. Thus، direct effect of these three traits on forage yield were calculated 0/726، 0/226 and -0/984 respectively by Path analysis. Finally، on the basis of the current result in this research compared with previous findings، it can be concluded that multivariate statistical methods can be useful to find relationships between quantitative characters in sainfoin.

Fusarium wilt disease is one of the major plant diseases that affect melon production. In this study a total of 23 landraces and breeding lines of melon were collected from different regions of Iran planted in a randomized complete block design with three replications and were studied to find new sources of resistant ones in the tray contained clay، pith mass and perlite in greenhouse. The root of seedlings after reaching at one to two true leaf stages were placed in a high inoculum concentrations of 1×106 spores per ml of Fusarium oxysporum f. sp. melon for 3-4 min and then، roots were wounded. Root samples from infected plants of all sensitive، semi-resistant and resistant genotypes were taken to examine biochemical changes for 8 days after 2 days of transplanting in 5 times and were kept in −80°C. The root of control plants dipped in tap water. The activity of peroxidase (POX، EC 1. 11. 1. 7)، polyphenol oxidase (PPO، EC 1. 14. 18. 1)، Catalase (CAT، EC 1. 11. 1. 6)، Superoxide dismutase (SOD، EC 1. 15. 1. 1) and Phenolic compounds (PCs) were measured. Area under disease progress curve and disease severity were studied to identify relationship between disease resistance and enzymatic composition. The results of analysis of variance showed that infection of melon seedling with F. oxysporum race 1. 2 led to many biochemical changes. The level of antioxidant defensive enzyme and PCs content increased in response to infection by the Fom 1. 2. The activity of POX، PPO، SOD، PCs and CAT in different genotypes approached to highest level at 4 days after inoculation. In clustering of cultivars via Ward method، 32 landraces clustered into three groups. Principal component analysis diminished all of variables to two components with 96% cumulative variances. Isabelle and Shadegani 2 landraces had the maximum genetic distance together. The Isablle and Shadegani 2 were identified as the most resistance and the most susceptible genotypes، respectively. The Isablle، Zard Eyvanakey، Charentais Fom1، Japalizi and Maghasi placed in the same group. Therefore، by crossing between these land races، the basic population could be obtained to study the gene action and to identify the effective gene (s) regarding tolerance to fusarium wilt.

In order to investigate the variation within and among populations of Parrotia persica C.A. Meyer based on leaf morphological traits, three populations were selected from Behshar area, in the east of Mazandaran Province. The populations selected along a transect in different altitudes of 182, 340, 540 meter above the sea level, respectively. In each population, 10 trees were selected and some leaves were collected from middle crown in early October. Leaves mixed together and then five leaves were selected randomly for study.

Many polymorphisms exist in field bindweed (Convolvulus arvensis L.) populations. These differences that appear especially in their flower and leaf cause to different biotypes of this weed that are different in view of dry weight, rate- and flowering period. This research was accomplished during 2005 to 2006 at Weed Research Department, Iranian Plant Protection Research Institute for identification of morphological and physiological variations of field bindweed population and introduction of these weed biotypes in Varamin. The analysis of the character was done by Principal Component Analysis (PCA) and Cluster Analysis (CA) based upon 43 morphological and physiological variables. The most important variable was Leaf Dry Weight. Results of this experience showed 15 biotypes in Varamin. The variability in morphological and physiological of these field bindweed biotypes may explain their different adaptability as the environmental conditions and different management practices change.