a. arzani

Beekeeping on rangelands is considered as a key approach for sustaining pastoral livelihood and reducing pressure on grazing lands. Previous studies are mostly focused on the ecological contributors of apiculture and the social criteria are not treated in much detail. The current research, therefore, uses the case of Sarayan Arid Rangelands in northeast Iran to examine the importance of social capital in adaptation of beekeeping as a pastoral livelihood diversification strategy. Through a random sampling procedure, 180 herders were selected in the study area. Questionnaires were used to collect data on trusts, collaboration, and solidarity as the main determinants of social capital and also herders' interests in beekeeping. Stepwise linear regression method was employed to estimate the relation between herders' interest in beekeeping and their social capital. The results show that about 33% in variance of motivation on beekeeping as a livelihood diversification strategy could be explained by the cooperation, trust, and solidarity among the rangeland users. Therefore, it is vital to introduce policies and measures to support collaboration and social networks among the rangeland users.

The effects of salinity stress on grain quality traits of wheat were investigated using 180 lines of F5 generation in two environments (normal and salinity stress). A randomized complete block designs with three replications was used in each of the environments at the Research Farm of the Agricultural and Natural Resources Research Station of Isfahan in 2019-2020 cropping season. Grain yield, protein yield, grain moisture content, grain hardness, volume of Zeleny sediment, protein content, bread volume, wet gluten percentage, and gluten index were evaluated. Analysis of variance showed that there were significant differences among the lines for all traits studied in two environmental conditions. Moreover, the results showed that the quality in bread wheat was improved under salinity stress conditions due to increment in protein content and grain hardness. Grain protein yield in both environments had a significant and negative correlation with grain moisture as well as bread volume. In the other hand, grain hardness showed a significant and positive correlation with the Zeleny sedimentation and water absorption in both environmental conditions. The results showed that the identification of favorable quality characteristics in normal and stressed conditions were possible and the lines with high grain quality can be used in breeding programs for improving baking quality. Although salinity caused the decrease in grain yield, the content of protein and the Zeleny sedimentation volume increased in this condition.

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.

In this study, to determine the optimum crop pattern of Kermanshah plain, Iran, a dynamic model was developed in Vensim PRO x32 software to simulate the actual situation in the region. Stochastic simulation of time series method was used to predict the values of climate parameters in the future. After ensuring the performance of the dynamic model as well as time series model, optimization process of crop pattern was performed using the existing optimization tool in Vensim PRO x32 software in addition to multi objective mathematical programming approach by Powell method in three different scenarios. The objective functions included maximizing the economic benefit for farmers and minimizing the extracted water from aquifer. The results showed that ratio of the gained benefit to the amount of water extracted from the wells in optimized conditions was always higher than the current conditions. The value of this ratio for the three scenarios was 1.23, 0.89, and 0.94, respectively, which in all three scenarios are higher than the current value (0.68). The results showed that according to a case in which variations in the crop coefficients of all crops are possible, in order to optimize the crop pattern,  the area allocated to wheat, barley, grain and forage maize, tomato, clover, and onion must be decreased in the current crop pattern. Furthermore, the results of optimization indicated an increase in the area under the cultivation of saffron, rose, greenhouse, medicinal plants, and olive, compared to the current conditions.

Due to lack of physical, emotional and psychological preparation, premature birth may cause a lot of stress for parents and may have consequences for both parents and infants. Since some parents have difficulty participating in face-to-face training programs, this study was conducted to determine the effectiveness of a training program based on virtual participation on stress and anxiety of parents with premature infants

This quasi-experimental study was performed among 80 parents of premature infants admitted to Amirkola Children's Hospital and Ayatollah Rouhani Hospital, who were randomly assigned to intervention and control groups with 40 participants in each group. The parents of the intervention group received the content of the virtual participation training program asynchronously in the form of Telegram groups within four days. The control group received no intervention other than the usual methods and support of the ward. Then, the State-Trait Anxiety Inventory (score 40-160) and the Parental Stress Scale (score 31-155) were completed and compared on the third and seventh days for both groups and on 13th day for the intervention group.

Results showed that parental stress score decreased from (97.118±21.68) to (86.27±00.27) (p<0.001) in the intervention group. In the control group, it changed from (76.103±30.44) to (91.99±31.82), which was not significant. In investigation of the effect of time on parental stress subscales, the mean scores of the questionnaires showed a significant difference from day 3 to day 13 in regard with the components of stressful parental experiences, relationship with the infant and parental role, parental experiences about behavior, appearance and treatment of the infant, and environmental stress (p<0.001). The parental state anxiety score in the intervention group changed from (45.68±4.63) to (46.63±3.54) and in the control group from (46.25±6.38) to (46.83±5.21), and the parental trait anxiety score in the intervention group changed from (43.88±5.91) to (43.97±5.59) and in the control group from (43.18±5.62) to (42.17±6.63), which was not significant.

The results of the study showed that training program based on virtual participation reduces the stress of parents with premature infants.

To study drought stress effect on grain quality properties of wheat, an experiment was conductedusing 169 recombinant inbreed lines (RILS) under water stress and non-stress condition and with two separated lattice designs. Grain yield, protein yield, protein content, volume of Zeleny sediment, grain hardness, water absorption, grain moisture content and grain dry matter were evaluated. Analysis of variance showed that there were significant differences among the lines for all traits. Moreover, comparison between two lines in two environmental conditions showed, the quality in bread wheat under drought stress conditions due to increment of protein yield is improved. Protein yield in both irrigation regimes has a significant and negative correlation with grain moisture and in the other hand, significant and positive correlation with the grain hardiness dry matter, Zeleny sedimentation and water intake in both conditions. The results showed that the identification of favorable quality characteristics in optimum and stressed conditions were possible and the lines with high grain quality can be used in breeding programs for improving of baking quality. Although some drought sensitive genotypes possessed a favorable baking quality but their grain yield was low.

Angelica archangelica, Tanacetum cinerariaefolium and Chelidonium majus are valuable medicinal plants for which there is no comprehensive information about their seed germination in review of literatures. With regarding of the importance of simple propagation of medicinal plants and the role of seed in production of these plants, this study was set out in order to analyzing of the effects of cold stratification (control, 2, 3 and 4 weeks) and acid gibberellic (control, 100, 150, 250, 350, 450, 500 and 1000 ppm) treatments on seed germination of these species. Treatments were arranged seperately in a Completely Randomized Design with 3 replicates. The results showed that the highest mean germination (percentage and rate) was observed in 3 and 4 weeks (40%) and 4 weeks (1.8 seeds per day) cold stratification for Angelica archangelica seeds, 3 weeks (42.67%) and 4 weeks (6.17 seeds per day) cold stratification for Tanacetum cinerariaefolium seeds, and 100 and 350 ppm (100%) and 500 ppm (5.22 seeds per day) GA3 solutions for Chelidonium majus seeds.

Identification and determination of genetic purity of rice hybrid varieties for seed certification and control is an essential issue regarding to apply hybrid rice technology in Iran. Therefore، usefulness of microsatellite markers (SSR) for fingerprinting and genetic purity testing were investigated. Eight F1 rice hybrids and their parental lines were evaluated using 14 microsatellite markers in which 10 markers had reproducible polymorphic bands among genotypes. Totally 27 bands (alleles) produced، average number of band per primers and per genotypes were 1. 92 and 1. 68، respectively. Genetic purity was tested in respect of microsatellite fingerprint and polymorphic primers which detected off types seeds among F1 hybrids. Extra band (s) was also observed when the F1’s SSR products were analyzed. Null alleles were appeared in three restorer lines for RM264 microsatellite locus. Cluster analysis based on shared allelic similarity coefficient، using UPGMA algorithm، grouped the 16 rice genotypes into three main clusters، each containing 43. 75%، 43. 75% and 12. 5% of genotypes. Overall، these results indicated there are reliable tools of microsatellite markers in DNA profiling and seed purity testing in rice varieties، especially hybrids.

To evaluate physiological traits and traits related to grain quality of 18 triticale lines including 9 doubled haploid (DH) and 9 corresponding F6 lines, an experiment was conducted at research farm of College of Agriculture, Isfahan University of Technology located in Lavark- Najaf Abad in 2007. A randomized complete block design with 4 replications was used. Protein content, flour protein, gliadine, glutenin- secalin, SDS sedimentation volume, test weight, length, wide and area of flag leaf, chlorophyll content and grain yield were evaluated. The tested DH and F6 lines were significantly differed for most of studied traits with the exception of the SDS sedimentation volume, test weight, gliadine and length of flag leaf. F6 lines were superior that DH line for grain quality related traits. Significant and positive correlations were observed between grain yield and with length of flag leaf, while grain yield had a negative correlation with protein percentage and protein content, measured by spectrophotometer. The highest genetic coefficient of variation was observed for chlorophyll and the lowest one was for test weight, wide and length of flag leaf. The highest and the lowest broad heritability estimates were 99 ٪ for chlorophyll content and 28٪ for SDS sedimentation volume, respectively. Overall, F6 lines performed superior than DH lines for quantity-related and physiological traits.

Sainfoin (Onobrychis viciifolia Scop.) is a perennial legume widely adapted to environmental conditions and has been successfully used as a pasture and hay forage in Iran. This experiment was carried out to investigate yield potential and genetic variation of morphological, agronomic and qualitative traits using 10 Iranian sainfoin populations. The experiment was conducted as a randomized complete block design with four replications ON Research Farm, Isfahan University of Technology. Results indicated that there are significance differences between populations for most of the traits. The estimates of heritabilities for forage yield, number of stem per plant, number of node and qualitative traits were over 50 percent. The high phenotypic and genotypic coefficients of variability for economic traits showed that a broad genetic diversity in this germplasem can be exploited in breeding programs. Significant differences were found among cuts and cut × population interaction for all characters. The third harvest produced 41.6 percent of total hay yield. Evaluation of traits related to forage quality revealed that the highest proportion of leaf to stem belong to Sarab and Oromieh populations (6.28 and 6.82, respectively). Crude protein percentage was significantly different among cultivars and Golpayegan population had the highest value for Crude protein percentage. Feridan, Khonsar and Golpayegan populations produced the highest dry matter yield in the first, second and third cut, respectively. These populations were found as the high potential accessions, which can be used as a source for agronomic and plant breeding research in the region..

In order to investigate the relationship among seed yield and its components in safflower, path and factor analysis were conducted using the agronomic and morphological traits of 32 genotypes. Genotypes were evaluated on the Research Farm of Isfahan University of Technology, using a randomized complete block design with three replications. The correlation coefficients showed that number of seeds per capitula and number of capitula per plant had the highest positive correlation with both seed yield and seed yield per plant. The results of regression analysis showed that number of capitula per plant explained 43.6%, and along with seeds per capitula and plant height 60% of the phenotypic variations for seed yield. The regression analysis for seed yield per plant also revealed that seeds per capitula, capitula per plant and seed weight in order had more contributions to the variation of seed yield per plant and explained 81.2% of its variation. Path analysis showed that capitula per plant had the most direct positive effect on both seed yield and seed yield per plant however, this effect was decreased by the indirect and negative effect of seed weight. Results of factor analysis recognized 3 main factors which explained 81.81 % of total variation of the data. These factors were named the seed yield and its components, phenological traits and branching. In general, it can be concluded that seeds per capitula, capitula per plant and seed weight in order contributed more to the seed yield of safflower genotypes. In conclusion, these yield components can be used as selection criteria in breeding programs.

Field crop landraces are valuable genetic sources. Twenty populations of Persian clover (Trifolium resupinatum L.) collected from different areas of Iran were used in this study. DNA extractions were carried out using minipreparation method with equal amount of leaves from 30 plants of each population. DNA samples from 20 clover populations were evaluated using semi-random (ISJ) markers. Ten primers out of 30 which used IT (intron-targeting) and ET (exon-targeting) primers produced repeatable bands. Cluster analysis was conducted using NTSYS software and UPGMA method based on Jaccard's similarity matrix. Primers totally produced 111 bands, of which 93 bands (%93) were polymorphic among clover genotypes. The greatest and least amplification fragments belonged to IT15-31 and ET18-4 primers, respectively. Average band number per primer was estimated 11.1 bands. Furthermore, IT primers produced more polymorphic DNA fragments with higher resolution. Based on cluster analysis and cutting dendrogram in 0.8 similarity coefficients, clover populations were divided into five groups in which Kazerun and Kermanshahi (1) individually formed a separate cluster. According to similarity matrix, the least similarity (%42) belonged to Alvijan and Kazerun and the highest similarity belonged to Chegeni and Haftchin Hamedan. Clustering based on semi-specific PCR method almost substantiated the grouping based on geographical origin. Considering the results, it is concluded that PCR-based semi-random marker technique can be used for genetic diversity study of Persian clover as well as discrimination of its cultivars.

Sugarcane (Saccharum officinarum L.) is one of the most important sugar crops that provides the major part of consumed sugar of the people worldwide. Because of the excessive demand for sugar and its byproducts, cultivation of sugarcane is expanding rapidly in subtropical arid and semi-arid regions such as south-west of Iran. Salinity is an important abiotic stress that causes reduction in sugarcane yield under saline and sodic conditions of soil and water in Khuzestan province. This study was conducted to evaluate seven commercial and promising sugarcane cultivars at formative stage for different stress tolerance indices and distribution of genotypes and indices in 3-D plots and biplots by using a complete randomized design with three replicates and four salinity treatments (0, 0.25, 0.5, 0.75 % NaCl) in a hydroponics system at research greenhouse of Isfahan University of Technology (IUT). Different tolerance and sensitivity indices for dry weight yield of sugarcane cultivars showed that NCO-310 genotype had high dry matter yielding potential in all stress levels. Also CP82-1592 genotype in medium and high level stress intensities had potential to yield relatively high dry matter and low sensitivity to salinity stress. Based on stress tolerance index (STI) revealed that NCO-310 (a commercial cultivar) and CP82-1592 (a promising line) at all salinity levels were the most tolerant cultivars.

Drought stress is one of the most important environmental stresses that reduces grain yield dramatically. Grain yield results as a complex trait from contribution of many traits in plant, and evaluation of morphological traits with less complicated inheritance under different environmental conditions and related to grain yield could be used as selection criteria. To study the genetics of traits related to plant stature and flag leaf area, a cross was made between durum wheat cultivars Oste-Gata (drought tolerant) and Massara-1(susceptible). Their F1, F2 and F3 progenies were evaluated under normal and late-season drought stress using a randomized complete block design. Generation mean analysis was performed by scaling test which essays all generations simultaneously. Analysis of variance of generations showed that all traits except of width of flag leaf, differed significantly between generations. Three parametric models contain m, d and h had the best fit. Although both additive and dominance components were involved in the expression of all the traits under both environments, yet the dominance component suffered more than the additive component. Dominance variance was contributed in plant height, peduncle length and length of flag leaf more than additive variance. Therefore, these traits can not be used as selection criteria. There was no epistatic effect for the studied traits, indicating the lack of gene intractions for the traits in the segregating populations.

Sugarcane is one of the most important sugar crops in the world. Because of semi-arid climate and salinity of its cultivation area in our country, increasing salt tolerance of sugarcane is signifying. To achieve this goal determining salt tolerant cultivars and understanding salinity mechanisms in sugarcane are very important. This study was conducted to evaluate 8 commercial and promising sugarcane cultivars at early stage of growth. A complete randomized design with three replicates and four salinity treatments (0, 0.25, 0.5, 0.75 % NaCl) was used in a hydroponics system. The effect of salinity on absorption, transport and accumulation of Na+, Cl- , K+ and Ca2+ ions in shoot and root was determined. At high level salt concentration, Cl- content in shoot and root increased. Result showed that sodium accumulation in sugarcane plants was more than potassium. By increasing salinity level, sodium uptake and its translocation to shoots increased reducing growth and dry matter yield of plants. With rising salt concentration from medium (0.5%) to high (0.75%), content of chloride in shoot and root of NCO-310 was constant showed that this cultivar had genetic ability to avoid Cl- uptake. CP82-1592 with lowest ratio of shoot / root chloride had minimum transport of Cl- to shoots. Also this cultivar had high content of Ca2+ in shoot and low Na+/Ca2+ ratio at all salinity levels. CP48-103 had low sodium in shoot and relatively low sodium in root. Thus it probably has genetic potential to avoid sodium uptake. At last, exclusion of Na+ and Cl- to older leaves and tillers was seen in CP82-1592 and CP72-2086 cultivars. According to results, to avoid once of absorption and transport, and exclusion of harmful Na+ and Cl- ions were mechanisms that could be used in salinity tolerance of sugarcane.

Evaluation of genetic improvement of grain yield and other traits in cultivars released in different years is useful to determine plant breeding impact on grain yield improvement, to define future selection criteria and to identify the desirable environment and traits for further assessment. This study was conducted to evaluate the genetic improvement for grain yield and other traits of twelve oat (Avena sativa L.) cultivars released in Canada during 1921- 1997, at Research Farm, College of Agriculture, Isfahan University of Technology, during 2001-3 in a randomized complete block design with three replications. The regression of mean grain yield on released year of the cultivars showed that the rate of increase in grain yield during a 76-year period is 32.63 kg h-1 year-1 or 0.63% per year. Breeding programmes have inereased harvest index, grain number per panicle and fertile tillers /m2. The effort of breeders in this period was to decrease plant height and days to heading. The other traits had small changes and showed no specific trends. In general the results of this study showed continous improvement of grain yield in this period. Genetic improvement of grain yield in evaluated cultivars closely correlated with harvest index. Therefore, most variation in grain yield of oats was due to variation in harvest index. Although much of the improvement in grain yield described here could be attributed to the increased harvest index, the scope for further improvement in this character may be limited. Further yield improvement of oats might be achieved by combining high biological yield with high harvest index.

An experiment was conducted to investigate the heterosis in 12 F1 hybrids of durum wheat using agronomic and morphological traits. Parents were selected according to the estimated genetic distances based on the results of a two-year field experiment, which were then crossed to produce F1 hybrids. Twenty-three genotypes (including 11 parents and 12 hybrids) were evaluated using a randomized complete block design with three replications Research Farm of College of Agriculture, Isfahan University of Technology, located at Lavark, Najaf- Abad in 2003. Agronomic characteristics comprised days to 50% flowering, days to 50% pollination, days to maturity, plant height, spike length, grain weight per spike, number of grain per spike, number of spike per m2, 1000-grain weight, biological yield, grain yield and harvest index. The results of analysis of variance showed significant differences among parents F1 hybrids and parents vs. crosses for all the studied traits. Substantial differences in the level of heterosis for plant maturity were detected among the hybrids with the highest heterosis belonging to HPI40100×PI40099 and HEupoda6× Chahba88 hybrids. Furthermore, superior hybrids included HAltar84/Ald×Chahba88, HBuchen7×Chahba88 and HEupoda6×Mexi75/Vic possessing the highest heterosis for grain yield and grain yield components among 12 hybrids of the present experiment. Eventually, it is concluded that Eupoda6, Odin12, Altar84/Ald and 45063Karaj genotypes when crossed with Mexi75/Vic genotype as well as Buchen7 and Altar84/Ald genotypes when crossed with Chahba88 genotype produced superior F1 hybrids.

The most desirable approach to improve characteristics such as yield with polygenic inheritance and genotype × environment interaction, is simultaneous selection using selection index based on related traits. This study was conducted Research Farm of Isfahan University of Technology, to compare selection indices for barley yield improvement under nitrogen stress and non stress conditions, using 49 F13 recombinant inbred lines derived from a cross between Azumamugi and Kanto Nakate Gold. A split plot design with randomized complete block layout in three replications was used. In non-stress condition 100 kg nitrogen per hectare as urea was used at early reproductive growth, stem elongation and grain filling stages. In stress condition, 50 kg nitrogen per hectare was only used at early vegetative growth stage. Smith-Hazel and Pesek-Baker indices based on 4 traits (days to heading, harvest index, growth rate and nitrogen harvest index) and also direct and correlated response of these traits were calculated. The result of response to selection and correlated response indicated that the selection based on higher harvest index and nitrogen harvest index under both conditions screens high yielding lines. Harvest index had high weight in both indices under stress and non stress conditions. Under both conditions and for Smith-Hazel and Pesek-Baker indices, growth rate had negative correlation coefficients. Therefore, the selection based on these indices, separates lines with lower growth rate. In this study, Smith-Hazel index had higher efficiency.

DNA markers have provided valuable tools for plant breeding and beneficial for germplasm characterization and indirect selection. Marker-assisted selection has the potential to deploy favorable gene combinations for disease and pest control as well as the quality of some crop products. However, practical application of molecular marker revealed that a successful MAS program depends on inheritance of the trait, number of individuals subjected to analysis and the genetic background. In this study, microsatellite (SSR) markers linked to the Russian wheat aphid (RWA) resistant gene (Dn4) and glume-color gene (Rg2) in wheat using a population of F2–derived F3 families derived from F2 single plants originating from a cross between the susceptible line (synthetic hexaploid-11) and the resistance cultivar (Halt) are reported. Two flanking microsatellite markers Xgwm106 and Xgwm337 are linked with Dn4 on the short arm of wheat chromosome 1D at 5.9 cM and 9.2 cM, respectively. The accuracy (AMAS) and efficiency (EMAS) of marker-assisted selection were calculated for homozygous RWA resistant genotypes of Dn4 gene in the F2 generation. Dominant morphological marker, Rg2, was also used for marker-assisted selection of Dn4 gene individually and in combination with microsatellite markers. EMAS of 100% for Xgwm337 marker and AMAS of 100% for bracketing markers Xgwm337-Xgwm106 and Xgwm337-Rg2 and non-bracketing markers Xgwm106-Rg2 were obtained.

An experiment was conducted to investigate the genetic diversity in the cultivars and F1 hybrids of durum wheat, using agronomic and morphological traits. Evaluation of consistency between choosing parents of crosses based on morphological and agronomic observations and genetic distance obtained from cluster analysis were objectives of this study. Fourty- two genotypes were evaluated using a randomized complete block design with three replications in 2003. Agronomic characteristics comprised days to 50% flowering, days to 50% pollination, days to maturity, plant height (cm), spike length (cm), grain weight per spike (gr), number of grain per spike, number of spike per m2, grain yield (t/ha), biological yield (t/ha), 1000 grain weight, test weight (gr/L) and harvest index were measured in the studied genotypes. The results of analysis of variance showed significant differences among genotypes for all the studied traits. The results also revealed that grain yield had the highest coefficient of variation (CV= 21.6%), followed by spikes per m2 (CV= 20%) and number of grains per spike (CV= 18.9%). Lowest coefficient of variation was observed in days to maturity, days to 50% pollination and days to 50% flowering. Moreover, correlation analysis indicated that grain yield correlated with harvest index, biological yield, grain per spike and grain weight per spike. Cluster analysis of genotypes based on agronomic traits defined desirable clusters. These clusters have desirable characteristics and are beneficial for breeding objectives. Results of evaluation of consistency between choosing parents based on observation and those of cluster analysis showed varing degrees of consistency in 12 conducted crosses, ranging from highly similar parents in Eupoda6×Chahba88 to relatively distinct parents in PI40100×PI40099 cross.

The Genetic basis of grain yield and related characteristics were studied by a generation mean analysis in five crosses of winter wheat (Triticum aestivum L.). “Roshan”, “Mahdavi”, “Inia”, “Atila” and “Goscoyin” cultivars along with their F1, F2, BC1 and BC2 populations were evaluated by a split-plot design with crosses as the whole plot in a randomized complete block design with two replications and generations were applied as the subplots. Analysis of variance revealed significant differences among generations for studied characteristics including the grain yield per plant, the number of spikelet per plant, the number of spikelet per spike and grain weight per spike. For the majority of traits and crosses, F/DH1/2 was less than one, indicating that the sign and magnitude of gene actions were different. Estimates of broadsense and narrow sense heritabilities were low for the grain yield per plant compared with other traits, rating from 28.5% to 58.6% and 24% to 48,5% for the five crosses, respectively. Genetic components of generation means were calculated by fitting different models and choosing the best model indicated that the impact of additive, dominance and epistasis genetic components in controlling the traits depend on the cross and the trait under study.

To evaluate heritability, phenotypic and genotypic correlation coefficients, phenotypic and genotypic variances as well as relationships between some of the grain quality traits, an investigation was conducted in a randomized complete block design replicated three times in 2001, using four durum wheat genotypes PI40100, Dipper-6, Oste/Gata, Shova and their F2 and F3 progenies derived from their crosses. Grain quality characteristics including seed hardiness, protein content, SDS sedimentation volume and gluten content were evaluated. The results indicated that wet gluten content and dry gluten content had the highest coefficient of variation. Statistical analysis showed a significant difference between genotypes for all traits with the exception of SDS sedimentation volume. Dry gluten content had the highest heritability (90.4%) while SDS sedimentation volume had the lowest heritability (48.6%). Results of correlation analysis indicated that seed hardiness correlated significantly with protein content, SDS sedimentation and dry gluten content. Protein content had a positive correlation with wet and dry gluten content. Since dry gluten content showed a high correlation with protein content (quantity) and seed hardiness had a high correlation with SDS sedimentation volume, hence these two traits can be used as the selection criteria for improving quality of protein in durum wheat.

This study was conducted to analyze the correlation among grain yield, yield components, duration of vegetative and grain filling periods in twelve oat (Avena sativa L.) cultivars at the Research Farm of the College of Agriculture, Isfahan University of Technology, from 2001 to 2003. A randomized complete block design with three replications was used. The correlation coefficients among the grain yield/m2, fertile tiller/m2, grain number/panicle and the duration of grain filling period were positive and significant. Among yield components, the number of panicle/m2 and the number of grain/panicle had the largest direct effects on grain yield (0.68 and 0.30, respectively). Furthermore, the duration of the grain filling period had the highest direct effect on the number of grain/panicle and the grain weight (0.82 and 0.80, respectively), which were greater than its correlations with the number of grain per panicle (0.42) and 1000-grain weight (0.35). However, its negative indirect effects through other traits reduced the correlation coefficients. The results of path analysis indicated that the number of panicle/m2 and the number of grain/panicle had the largest direct effects on the grain yield. Considering the direct effects of grain filling duration on the number of grain/panicle and the 1000-grain weight, and also the fact that most of the dry matter in oat is produced in this period, it seems plausible to use these traits as a selection criterion in breeding programs for higher yields of cultivars of oat.

In order to study the effects of different levels of nitrogen fertilizer and plant density on grain yield and its components in sunflower, an experiment was conducted using 'Record' cultivar at the Research Farm of College of Agriculture, Isfahan University of Technology in 1996. Four levels of nitrogen (0, 75, 150 and 225 kg/ha) and four plant densities (65000, 75000, 85000 and 95000 plants/ha) were used in a split plot arranged in a randomized complete block design with three replications. Developmental stages, plant height, stem diameter, head diameter, number of head per m2, grain yield, biological yield, harvest index, 1000-grain weight, number of grains per head, grain oil percentage, oil yield and grain protein content were measured. The results indicated that N fertilizer caused an extension of the growth period and means of days to physiological maturity. It also increased plant height, stem diameter and head diameter. While increasing plant density had an incremental effect on plant height, it negatively affected stem diameter and head diameter. N fertilizer up to 150 kg/ha increased the grain yield and biological yield, whereas higher levels of N fertilizer decreased both. Plant density of 85000 plants per hectare was observed as a suitable plant density, whereas the higher plant density had a negative effect on grain yield. N fertilizer via increasing the number of grains per head, and plant density via increasing the number of heads per unit area and also decreasing the number of grains per head influenced the grain yield. One-thousand grain weight was not affected by neither N fertilizer nor plant density. Considering the superiority of 150 kg/ha of N fertilizer and plant density of 85000 plants/ha for grain yield and oil yield, it appears that they could be recommended for producing desirable yield in the regions similar to the study region.

Genetic variation of 300 genotypes of durum wheat comprising CIMMYT/ICARDA and Iranian germplasm was evaluated in 1999-2000 at Researh Farm of College of Agriculture, Isfahan University of Technology located at Lavark, NaJaf-Abad. Days to heading, days to maturity, plant height, spike length, grain weight per spike, number of grain per spike, number of spikes per m2, 1000-grain weight, test weight, grain yield, biological yield, and harvest index were recorded. Coefficients of correlation, step-wise regression, factor analysis and cluster analysis of characters and genotypes were conducted using the studied traits. Results indicated that considerable genetic variations exist for the traits and, in particular for grain yield, harvest index, number of spikes per unit area and number of grain per spike. Grain yield had a positive and significant correlation with days to heading, days to maturity, number of grain per spike and grain weight per spike. Factor analysis for the genotypes detected 6 factors, which explained 76.7 percent of the total variation among data. These factors basically involved potential of assimilate distribution, different aspects of plant storage, source-sink relationships, plant height and tillering potential. Cluster analysis was similar to factor analysis in grouping the characters. According to cluster analysis, the genotypes were calssified into 6 clusters with significant differences among all groups. Mean comparisons of traits in these groups showed that genotypes of groups 5 and 6 were superior in grain yield and harvest index and are beneficial to the local durum breeding objectives.