All breeding programs and the development of new superior cultivars around the world are based on germplasm genetic diversity. In order to identify the phenotypic diversity and the morphological and agronomical traits relationship among 57 cowpea accessions,  the study was implemented in the field of the National Plant Gene Bank of Iran,in the 2019-20 growing season, The most important phenological, morphological and agronomic traits were recorded. Analysis of variance showed the existence of genetic diversity between the understudied accessions in terms of all quantitative traits except the number of pods per peduncle. The emphasis that it is possible to find out the desired trait among these accessions. Biomass, number of pods per plant, number of seeds per pod, pod length and 100-seed weight had the highest coefficient of variation. The range of phenological traits of day to 50% flowering (43-103) and day to maturity (69-177) showed that these accessions could be categorized as early, medium and late- maturing biotypes. Grain yield and harvest index had a significant negative correlation (P <0.01) with phenological traits. The 100-seed weight and pod length (P <0.01) were determined as traits affecting grain yield. The results of the principal component analysis showed that the three components explain seventy-two percent of the variability between the accessions. Plant height, number and weight of pods per plant, seed number in pod and grain weight per plant had the highest coefficients in the first component and day to flowering, day to maturity and grain yield had the highest coefficients in the second component. A bi-plot drawing of components and grouping genotypes based on  the traits showed that seventeen accessions are noticeable from yield component point of view. Also, seventeen accessions categorized as early-mature accesssins with high grain yield These results in one hand provide useful information about the agronomical traits diversity among local cowpea landraces and on another hand enable the selection of promising genetic resources for use in future breeding programs.

Flower yield in Rosa damascena is a complex trait that is affected by many traits and environmental factors. Therefore, studying the relationships among traits can be an essential step in selection to improve flower yield. Path analysis by identifying the main components of yield with a high direct effect plays an important role in the selection success, especially indirect selections through yield components. Due to the lack of resources in this regard, the present research aims to identify and determine the effective traits in flower yield, estimate the relationships among traits, and analyze the causality to identify their direct and indirect effects on flower yield via path analysis. 

The germplasm used in this research included 49 genotypes of Rosa damascena Mill.) belonging to different regions of Iran. One-year saplings of the genotypes were planted in April 2004 in the Zaleh research station, Sanandaj (Kurdistan province, Iran), based on the randomized complete block design (RCBD) with three replications and three plants in each plot with three meters of planting distance. Irrigation of the field was carried out in drip form for 15 days. The investigated morphological traits (plant height, number of flowers, etc.) in 2008 were measured on a 5-year old plant, and for the phenological traits (days until leaf opening, flower opening, etc.) the average of three years (2006 to 2008) was used. Data variance analysis was done based on RCBD design. Phenotypic correlation among traits was estimated, and path analysis was done in three steps of estimation of direct, indirect and residual effects of traits on flower yield.

The results showed significant differences (p≤0.01) among the genotypes for studying traits. The correlations of phonological traits with flower yield (FY) were significantly negative, while its relationships with morphological traits were significantly positive. The results of path analysis showed that the number of flowers per plant (FN) and fresh flower weight (with the direct effects of P=0.97** and P=0.33**, respectively, and residual effects of R=0.195) were the main components of flower yield. The total green surface of the plant (TGS) and plant crown diameter (with the direct effects of P=0.56** and P=0.28*, respectively, and R=0.395) were the main components of FN. Also, the number of leaves per plant and average leaf area (with the direct effects of P=1.02** and P=0.085*, respectively, and R=0.237) were the main components of TGS. 

Thus, FN and FFW can be used in indirect selections for FY improvement in Rosa damascena. The other studied traits affected FY indirectly via FN mainly (phonological traits negatively and morphological traits positively). Although the correlation of the height and crown diameter of the plant with FY was positive and very significant, the direct effects of the supplementary stages and the causality analysis sequence showed that the crown diameter (horizontal growth) is more effective than its height (vertical growth) in the reproductive processes of the rose. In other words, the genotypes with higher flower yield usually rise up to a certain height and spread leaves after that.

Rye (Secale spp.) is native to Southwest Asia and it two species including S. cereale and S. strictum is grown in Iran. This study was conducted to evaluate the diversity of phenological, morphological, and cytogenetic traits in two species of this genus. In this experiment, seeds of 91 ecotypes (including 78 S. cereale and 13 S. strictum) were provided from National Plant Gene Bank of Iran. Seeds sown in the research farm of the Seed and Plant Improvement Institute, Karaj, Iran, in the 2014-2015 crop year. All phenological and morphological traits (quantitative and qualitative) including 23 traits were measured according to the instructions of the International Institute of Bioversity. The descriptive statistics parameters showed different range of variation in traits among the species. Multivariate analysis showed significant differences among the species for phenological traits as flowering date and maturation date and morphological traits as grain shedding index, ear color, spike length and the number of spikelets per spike. These traits were considered of great importance in species segregation. Cytogenetic evaluation of the chromosomes of S. cereale and S. strictum showed that although both species were diploid (2n=14), a noticeable difference in chromosome length and the average arm ratio was observed in these two species, which can help to identify cytogenetically differentiate between them. Overall, the phenological, morphological, and cytogenetic traits in rye species show considerable diversity and can be used to identify and differentiate of the species. If there is a time limit or impossibility of cultivation, cytogenetic evaluation can be used as a fast and reliable method to identify species.

In studying the phenological stages of crops, the growing degree-days (GDD) gradients is considered as an alternative to counting the calendar days. Genetic diversity of 86 Iranian cultivars and 184 Iranian wheat landraces were studied based on the phenological stages (day to booting, day to flowering, day to maturity and GDD of these stages) along with grain filling period, thousand grain weight and grain yield during the 2013-14 and 2014-15 growing seasons. The results revealed that there is a significant difference between cultivars and landraces and studied traits were able to effectively distinguish between cultivars and landraces. On the other hand, the results indicated that genotypes with different growth habits have a significant difference in terms of most of the phenological traits. That is implied that either directly or indirectly has been occurred on increasing the length of the grain filling period along with grain yield. Since the diversity of phenological traits was higher in landraces, they can be a valuable source of choice for improving these traits. Finally, due to the importance of the phenological stages, it is recommended that these traits be taken into account in terms of yield and yield components and GDD index can be used to obtain more accurate results.

Soybean seeds are sensitive to storage due to their high oil content and they aged quickly. Aging of seeds leads to a decrease in the percentage and speed of germination and ultimately to a decrease in seed yield. Although the aging rate can be reduced with proper storage methods, the application of some treatments on the aged seeds or spraying some substances on the plants obtained from these seeds can be effective in improving the seed yield. The use of anti-aging substances such as seaweed extract in plants can act as antioxidants and reduce the effects of aging.
 
In order to evaluate the phenological stages and yield of soybean, an experiment was carried out in the research farm of Shahrood University of Technology during 2019 and 2020 in three replications. The treatments include the initial seed quality in two levels (normal seeds and aged seeds) and seaweed extract (Ascophyllum nodosum) in four levels (control, priming, foliar spraying and combined application of priming and foliar spraying with a concentration of 0.3%). The experiment was carried out as a factorial in the form of a basic design of randomized complete blocks.
In this research, applying accelerated aging caused a significant increase in phenological traits in soybean plants. The use of seaweed extract as a priming and the combined use of priming and foliar spraying could increase the rate of occurrence of phenological traits to a significant level. The seed yield in plants obtained from aged seeds was 32.69% less than that of control plants. The use of seaweed extract as priming, foliar spraying and the combined use of priming and foliar spraying increase the seed yield by 43.54, 15.69 and 87.85 percent, respectively. Aging caused a significant decrease of 23.50 and 25.33 percent of final emergence percentage. Pretreatment of normal and aged seeds with seaweed extract in the first year increased this trait by 16.33 and 7.33% compared to the absence of seaweed extract. In the second year of the experiment, the application of seaweed extract resulted in a 12.67% increase in seedling growth under normal conditions, and an 8.33% increase was recorded with the application of seaweed extract under aging conditions.
 
In this study, the application of seaweed extract as seed priming better than foliar spraying. It is possible to recommend priming and the combination of priming and foliar spraying with seaweed extract to accelerate the occurrence of phenological traits in soybeans. The combined use of priming and foliar spraying of seaweed extract is recommended to improve the performance of soybeans in normal and aged conditions.

To evaluate the genetic variation of Rosa damascena as an important aromatic and medicinal species, 38 genotypes of this species were studied for the diversity of phenological and morphological traits (flowering period, plant height, canopy diameter, number of leaves at the plant, total green area of the plant, number of flowers per plant, fresh weight and percentage of dry matter content of flowers and flower yield per plant) in a randomized complete block design with three replications in Zalleh Research Station of Sanandaj, Iran during 2004-2008. The results showed significant differences (p < /em>≤ 0.01) among the genotypes, in terms of the studied traits. The average total yield of fresh flowers was 2427.4 g/plant. The genotypes belonging to temperate and cool areas had lower flower yields than those originated from hot and dry areas. Flower yield showed a significant  and positive correlation with the crown height and diameter, the number of leaves, total green surface, and the number of flowers per plant (p ≤ 0.01). The results of stepwise regression showed that the flower weight and number positively, while the total green surface and flowering period negatively correlated with flower yield. The results of cluster analysis (CA) grouping were relatively consistent with segregation based on the flower yield and characteristics of genotypes origin areas. The results of principal component analysis (PCA) showed high consistency with the CA results, but the genotypic separation in PCA method was clearer. The overall results of this study along with CA and PCA analyzes showed considerable rich genetic variation among the genotypes in terms of phenological and morphological traits and the possibility of using this diversity in Iranian Damask rose breeding such as improving flower yield through direct and indirect selections (through flower yield components) or hybridization of genotypes with a greater genetic distance for the use of higher heterosis.

In order to evaluate relations between phonological trains, yield components and grain yield of 30 soybean lines with different maturity groups, an experiment conducted as a randomized complete block design with three replications at the agricultural research station of agriculture and natural resources research center, Gorgan, Golestan Province in 1388. 13 traits of vegetative and reproductive growth stages, yield components, seed protein and its oil content were evaluated. Number of days to flowering, number of branches per plant, number of pods on main branches, the number of days to maturity, yield components and grain yield had positive correlation and significant effect. Grain protein and grain shell weight ratio had a significant and negative correlation with grain yield. In the stepwise regression model,79% changes in seed yield by number of days to flowing, seed number per plant, number of branches per plant, seed protein percent and weight of shell: seed ratio and 21% of remaining by other effect could be explained. The 5 are mentioned characters were used to analysis. Results showed that most direct and positive effect on seed yield related to the number of days to flowing and the number of branches per plant.

In order to study the phonological stages and growth period of invasive weed Ranunculus ficaria based on degree days and to study the effect of planting depth on sprouting the tubers roots of this weed، two separate experiments were conducted in CRD with 5 replications at Ferdwosi University of Mashhad in 2008. In the first study germinated tubers were planted in 5 cm depth and the observations were noted. In the second experiment، germinated tubers were planted in different depths of 0. 25، 1. 5، 2. 5، 5، 7، 10، 15 and 20 cm. The results indicated that lesser celandine continued the growth until 1014 GDD and 4 phonological stages were recorded in this period. Lesser celandine sprouted from all depths but required GDD for emerging from surface depths were less than 15 and 20 cm planting depth.

In order to evaluate grain yield potential and study dry matter remobilization to seed, 8 commercial bread wheat cultivars were examined in two separate experiments, using randomized complete block design with 4 replications in 2003. There were significant differences for most traits in normal and drought conditions. Sarday variety had the least grain yield in the two environments. There was considerable variation between genotypes for independent parameters of dry matter remobilization to different plant parts in the two environments. Factor analysis showed that seven factors accounted for 100 % of the data total variance in normal and drought conditions. Factor analysis also showed that the effective traits to components grain yield , height and phenological traits were important for the selection of appropriate genotypes. Calculation of drought resistance indices showed that four indices including mean productivity, geometric mean productivity, harmonic index, stress tolerance index were more effective than other indices for the selection of drought tolerant genotypes.