دکتر اسدالله زارعی سیاه بیدی

The selection of high-yielding genotypes is especially important in sunflower. Therefore, this study was conducted to identify interrelationships between different traits and the selection of the best sunflower hybrids.

In this study, 11 new hybrids along with four cultivars Golsa, Ghasem, Shams, and Farrokh were evaluated in a randomized complete block design with four replications in the agriculture research station of Kermanshah during 2019-2020. The phonological, morphological characteristics and yield and its components including days to flowering, days to ripening, plant height, stem diameter, head diameter, seed number per head, thousand seed weight, and seed yield were measured. In this study, the methods of genotype × trait (GT) and genotype by yield × trait biplot (GYT) were used to identify interrelationships between different traits and selection of the best sunflower hybrids.

Based on polygon view of GT biplot, the genotypes No. 4 and 11 had good characteristics regarding seed yield. The vector view of GT biplot showed high correlation between seed yield with stem diameter, plant height and seed number per head. Based on average tester coordinate (ATC) view of GYT biplot, the genotypes No. 5, 3 and 4 in terms of all positive yield-trait combinations were recognized as the best genotypes and genotypes No. 7, 13 and 6 as the weakest genotypes. According to the results, a significant positive correlation was observed between stem diameter, head diameter, plant height and early maturity in combination with seed yield. Therefore, it seems that traits of stem diameter, head diameter, plant height and early maturity could be used as a suitable selection criterion for increasing seed yield in sunflower.

Generally, the results indicated that hybrids No. 5, 3 and 4 were recognized as superior hybrids from the point of yield and other agronomic traits. These genotypes have the potential to be used in research-extension trials for introduction as a new cultivar for cultivation in the Kermanshah region. Also, the traits of stem diameter, head diameter, plant height, and early maturity could be used as suitable criterions in selecting for increased seed yield in sunflower breeding programs.

Studying the reaction of the different genotypes under different environmental conditions helps breeders to detect stable and high-yielding genotypes. In this regard, 11 new sunflower hybrids along with four cultivars (Golsa, Ghasem, Shams, and Farrokh) were evaluated in a randomized complete block design with four replications in four experimental field stations (Karaj, Sari, Kermanshah, and Dezful) during two cropping seasons. GGE biplot statistical method (genotype effect + genotype × environment interaction) was used to study the adaptation of genotypes in the studied environments. Results of combined analysis of variance indicated that the effects of environments, genotypes, and genotype × environment interaction were significant, suggesting that the genotypes responded differently in the studied environment conditions. Results of the GGE biplot method showed that the two first and second principal components of the GGE biplot explained 66.4% of the total seed yield variation. Based on the biplot polygon view, the hybrid RGK15×AGK1221 in Sari and Karaj locations and the hybrid RGK25×AGK330 and Shams cultivar in Dezful location were superior genotypes with the high specific adaptation. Besides, all environments had high discriminating ability so that could able to show differences between genotypes. Sari environment was the nearest environment to the ideal environment that had the highest discriminating ability and representativeness.

In order to economical assessment of transplanting compared with direct (conventional) cultivation of rapeseed (Ahmadi variety) as check in different sowing dates, this research carried out in farm of Kermanshah agriculture and natural resources research and education center and Seed and plant improvement institute in Karaj during 2018 and 2019. Treatments of this experiment included rapeseed cultivation in 7 October as control, transplanting in two and four leaf stage on 17 October, 1 November and 11 November. In this study, for getting to economic target used Partial Budgeting Technique and Benefit cost ratio. According to the results, in Alborz and Kermanshah provinces, the mean of grain yield of rapeseed in seed cultivation in 7 October was 3495 and 4857 kg.ha-1, respectively. In Kermanshah province to Alborz province, the mean of grain yield and net income of check treatment during experimental years was increased 39 and 72.2 percent, respevtively and Net present value check treatment with discount rate 20% was increased 78.9 percent. Comparing trnsplanting treatments in target regions, transplanting planting in Alborz province to Kermanshah was more profitable. Thus,in terms of crops and economic preference, rapeseed cultivation in 7 October treatment as check treatment was selected as the best treatments in target provinces.

Oilseed rape (Brassica napus L.) is a traditional oil crop in Iran. Conventional oilseed rape production during the past decades has been performed through manual sowing, transplanting, and harvesting. In cold and temperate regions of the Iran, due to delays in harvesting the previous crop, it is not possible to planting oilseed rape seeds directly. Delayed planting of oilseed rape can reduce grain yield. Therefore, oilseed rape seedling transplanting can be one of the appropriate solutions. On the other hand, seedling quality is an essential indicator for grain yield in oilseed rape, which is affected by many factors, including seedling age. In addition, the time of seedling transplanting is also very important. Therefore, transplanting is also more advantageous than direct sowing in terms of time management. Although there are many benefits of transplanting in oilseed rape production systems, the optimal age of oilseed rape seedling for transplanting remains unknown. Furthermore, inappropriate seedling age is always misleading in terms of whether older or younger seedlings are employed for transplanting in practice. Thus, it necessitates seeking an optimal seedling age and evaluating its effect on grain yield.

Two field experiments was conducted as randomized complete block design with three replications at research field of Seed and Plant Improvement Institute (SPII) in 2017-2018 and 2018-2019 growing season. There 7 treatments including seed planting on 7 October (control), transplanting of two-leaf seedlings and four-leaf seedlings on 17 October, 1 November and 11 November. The genotype used in this study was Ahmadi as a winter cultivar. The measured traits included days to flowering, flowering period, growth period, plant height, number of branches, grain per silique, silique per plant, silique length, 1000-grain weight and grain yield. SAS statistical software was used for data analysis and means were compared with LSD test.

The results of variance analysis indicated that days to flowering, flowering period, silique per plant and grain yield (P≤0.05) and grain per silique (P≤0.01) was significantly affected by the seedling and seed planting treatments. Results of this study showed that in two-leaf seedling transplanting treatments at different times of seedling transplanting, delay in flowering was observed, but the duration of flowering period was shorter in these treatments. Also, in the transplanting treatments at the two-leaf seedling, silique per plant and grain per silique were less than them in other treatments. The highest grain yield and net income observed in seed planting treatment (3495 kg ha-1 and 61.1 Iranian million rials ha-1). Higher grain yield components such as silique per plant and grain per silique due to early flowering caused higher grain yield in seed planting treatment. In contrast, grain yield was lower in transplanting treatments compared to seed planting method. However, among the transplanting treatments, the highest grain yield was observed in the four-leaf seedling transplanting on 17 October as 3332 kg ha-1.

The results of this study showed that transplanting of winter oilseed rape cultivar is not suitable in the two-leaf seedling stage and winter oilseed rape seedling should have at least four-leaf stage. In general, it seems that the late transplanting of oilseed rape seedlings to the farm in semi cold regions will significantly reduce grain yield compared to oilseed rape seed planting method.

Planting date is considered an essential factor in agricultural production and it affects the growth, and yield of rapeseed .In order to investigate the effect of delayed planting dates on some phonological traits, yield, and yield components of rapeseed cultivars, a split-plot experiment based on randomized complete block design with three replications was conducted during the growing season 2014-2016 at the research station of Islamabad Gharb, Iran. Experimental treatments were two planting dates (7 and 17 October) as the main plot and five rapeseed cultivars (Nafis, Nima, Okapi, Neptune and Elvis) as subplot. The results showed that the effect of year, cultivar and planting date and their interactions were significant on most of the studied traits. The values obtained in most traits on October 7 planting date were higher than October 17. The highest number of pods per plant (214 pods), number of seed per pods (25.31 seeds), and seed yield (6793 kg.ha-1) were related to the Nima cultivar on October 7. Also, at the planting date October 7, the highest 1000 seed weight (3.61 g) was related to the Neptune cultivar. The highest plant height in both years was observed on October 7. The values of the studied traits were higher in the second year than in the first year due to climatic conditions during the experimental years. Finally, it can be reported that with increasing delay in winter rapeseed planting, the growth and yield of this plant decreases and that Nima cultivar had acceptable yield in delayed planting date.

Sunflower is a semi-drought tolerant plant that due to its importance in oil production, the area under cultivation is expanding. But drought stress severely reduces the yield of grain and oil. Therefore, the production and introduction of hybrid cultivars can help increase performance. The first step in the production of hybrid is to identify parents based on their General and Specific combining ability and also to determine the type gene actions.

In order to investigate the combining ability of sunflowers inbred lines under normal conditions and drought stress, a study using 12 sunflower hybrids obtained from the cross of male sterile and tester lines with two controls, Qasem and Shams, in two separate experiments in the form of The design of randomized complete blocks with three replications was performed under two conditions of normal irrigation and drought stress.

The results of combined analysis of variance of the studied treatments under both normal and drought stress conditions showed that drought stress had a significant effect on all studied traits number of seeds per head. The effect of lines for plant height, oil percentage and head diameter and the effect of testers were significant for most traits except number of seeds per head, which shows a significant difference between the general combinability of lines and testers. Also, line 1 and tester 3 in both normal and stress conditions with a negative and significant combinability for the height of the parent plant is suitable to reduce this trait in the cross. In addition, line × tester interaction had a significant effect on most traits except 1000-seed weight and number of seeds. The Line 1 and Tester 1 with significant positive general combining ability (GCA) effects for grain yields were considered as suitable combiners for improving these traits. So that under normal conditions, hybrid No. 13 with grain yield of 5224 kg / ha had the highest grain yield and under stress conditions of hybrid No. 31 with an average of 3544.6 kg / ha had the highest grain yield.

The general results of this study show that the important traits of grain yield, oil percentage and oil yield are controlled by the dominance gene action, which can be improved by hybridization and best selection of parents in breeding programs.

The High-yielding cultivars must show their superiority in terms of seed yield and agronomic traits and should have yield stability across wide range of environmental conditions as well as under farmer’s conditions. Therefore, in the process of releasing a new cultivar usually after evaluation of candidate lines in the research stations, these lines must be also tested in the on-farm trials under conditions similar to those of farmers conditions. In the present study, the promising line HW118 was compared with the local check (Okapi) in an on-farm trials in two regions of the Kermanshah province (Harsin and Allahiar Khani). The results showed that in both regions grain yield of line the HW118 was higher than local check Okapi at delayed planting date. In Harsin, grain yield of line HW118 was 3226 kgha-1 where local check Okapi had only 2850 kgha-1 grain yield. Similarly, in Allahiar Khani line HW118 had grain yield of 4125 kgha-1 that was 25% higher than that of local check Okapi with grain yield of 3300 kgha-1.

The genotype × environment interaction is a major challenge in the study of quantitative traits because it reduces yield stability in different environments and also it complicates the interpretation of genetic experiments and is difficult to makes predictions. In this regard, to analysis of genotype × environment interaction and determine the yield stability of sunflower genotypes, 11 new sunflower hybrids along with 4 cultivars were evaluated in a randomized complete block design with four replications in four experimental field stations (Karaj, Sari, Kermanshah and Dezful) during two cropping seasons. In order to analysis of genotype × environment interaction was used the multivariate method of additive main effects and multiplicative interaction (AMMI). The results of combined analysis of variance indicated that 57.68, 7.60 and 16.93 percent of total variation were related to the environment, genotype and genotype × environment interaction effects, respectively. Also, the results showed that the first five principal components of AMMI were significant and described 97.64% of the variance of genotype × environment interaction. Based on biplot graph of mean seed yield and the first interaction principle, the genotypes G3 and G5 were identified as a high yield and stable genotypes. Also, the Dezful and Kermanshah environments due to their high interaction were recognized as the most ideal environments for distinguishing and separating sunflower genotypes. The cluster analysis of the studied environments was divided into two groups. According to the results of cluster analysis, Karaj, Sari, Kermanshah and Dezful locations were located in a group that indicates these locations had the high predictability and repeatability power.

Response of sowing date on some agronomic traits of spring canola cultivars was studied by using a split plot experiment based on randomized complete block design, during growing seasons of 2014 to 2016 at the research farm of Islamabad Gharb Station, Iran. Planting dates were considered as the main plot in three levels from October 7 to 27 and eleven spring canola cultivars as sub plot. In both years, planting dates of October 27 after emergence due to cold and frost was eliminated and the results of analysis of variance were carried out for two planting dates of October 7 and October 17. The results showed that the effect of planting date was significant on the seed yield. Mean seed yield of cultivars were 3738 kg.ha-1 on October 7th and 2245 kg.ha-1 on October17th, respectively. The cultivar Jerry produced the highest (4123 kg.ha-1) and the RGS003 lowest seed yields (2464 kg.ha-1). On planting date 7th of October, the highest seed yield was related to Jerry cultivar and the lowest seed yield was related to the Hyola 401 cultivar (1794 kg.ha-1) on the 17th of October.

The present study was carried out to determine the seeding rate for some hybrids and open-pollinated genotypes.  

A field experiment ina factorial experiment based on randomized complete block design was conducted at the Islamabad-Gharb Research Station during 2018-2019. Seed consumption was four levels of 2, 4, 6 and 8 kg.ha-1 and cultivars include hybrids (Natalie, Neptune and Marathon), open-pollinated (Nafis, Rohan, Nima) and R15 line.  

The results showed that the effect of seed consumption was significant on plant height, number of branches, pod per plant and seed yield. The Maximum plant height was obtained at the level of 8 kg of seed and it was significantly different from all other seed consumption. However, the highest number of shoots and pods per plant resulted in the lowest seed density. Seed yield had a different reaction to seed consumption. The highest seed yield was obtained at 6 kg per ha seed consumption (2919 kg.ha-1) However, there was no significant difference between the levels of 4, 6 and 8 kg.ha-1. Marathon produced the highest seed yield with an average of 3585 kg per ha. Oil content was also different between the cultivars and the highest percentage was obtained in Natalie, Neptune and Nima.  

In general, the best results were in seed consumption of 6 kg/ha and Marathon hybrid. The target density recommendations for hybrid seed are lower than open pollinated genotypes.

The present study was conducted to investigate oilseed rape transplanting at Islamabad Gharb research station, Islamabad, Iran, in 2017-2019 cropping seasons. A factorial experiment in randomized complete block design with three replications was carried out. Experimental treatments consisted of three transplanting dates; 17th October, 1st November and 16st November, and two seedling growth stages; two and four-leaf stages. The results revealed that transplanting date had significant effect on some traits such as seed yield, seed no. silique-1, silique no. plant-1, plant height, seed oil content and days to flowering. The seedling growth stage had significant effect on seed no. silique-1, silique no. plant-1 and seed yield. The results also showed that transplanting at four-leaf stage was better than two-leaf stage as the seed yield in this stage (2773 kg ha-1) was greater than two-leaf stage (2157 kg ha-1). Transplanting on October 17 produced more seed yield (3158 kg ha-1) than November 01 and November 16 with 2403 kg ha-1 and 1834 kg ha-1, respectively. Considering the results of this research, transplanting of rapeseed can be recommended for delayed planting, at 4-leaf stage and transplanting date on 17 October, in Kermanshah and similar environmental conditions in Iran.

The present study aimed to the effect of late and normal sowing date on agronomic characteristics of some spring and fall rapeseed cultivars was evaluated during two years.

A field experiment in a split plot based on a randomized complete block design was carried out with four replications at the research station of Islam abad-gharb. Main factor was planting date in two levels including September 27 and October 17 and sub factor was rapeseed cultivars including Okapi, Talaye, hyola 401, Zafar, RGS003 and sarigol.

The results of variance analysis showed that the effect of late planting was significant only on days to flowering and plant height. Grain yield decreased by 34.4% and 29.85%, due to the delay in planting date in the first and second year of the experiment, respectively. This decrease was due to the effect of late planting date on yield components, so that decrease in the number of pods per plant as the most important component of grain yield in rapeseed in the first and second years of the experiment was 32.7 and 30.2%, respectively. The results showed that the cultivars had significant differences for number of days to flowering, flowering duration, number of days to physiological maturity, plant height, number of pods per plant, grain yield and seed oil percentage. The mean of the data showed that Okapi and Talayeh as fall type cultivars had the highest grain yield with 5096 and 4906 kg ha-1 respectively.

Okapi and Talaie are suitable cultivars for the study area. Also, any delay in planting causes yields reduced compared to normal conditions. However, considering other existing issues can be ignored reduction in performance.

Medical pumpkin (Cucurbita pepo L. var. Styriaca) contains valuable edible oils and compounds that are used to prevent and treat prostate cancer. To evaluate the effects of vermicompost (no application, 5, and 10 t ha-1) as the main factor, biological nitrogen (no application and application of Barvar 1), and biological phosphorus (no application and application of Barvar 2) as sub-factors on the yield and yield components of medical pumpkin, an experiment was conducted as a split-factorial based on a randomized complete block design with three replications in Islam Abad-e-Gharb, Kermanshah province, in 2015. Studied traits included male to female flower ratio, number of fruits plant-1, number of seeds fruit-1, average dry fruit yield, stem length, number of days to flowering, seed yield, and seed oil yield and percentage. Vermicompost had a significant effect on the number of seeds fruit-1, dry fruit yield, and flowering date. The highest oil yield (30 kg ha-1) was obtained from the combination of bio-phosphorus application and non-application of vermicompost treatments, and the highest seed yield (195 kg ha-1) was obtained from the combination of bio-nitrogen, non-application of bio-phosphorus, and non-application of vermicompost treatments. A combination of non-application of bio-phosphorus and bio-nitrogen and application of 5 t ha-1 vermicompost treatments resulted in the least male to female flower ratio (39); however, the highest one (66) was obtained in the combination of non-application of bio-nitrogen, application of bio-phosphorus, and  10 t ha-1 vermicompost. In general, the highest seed and oil yield was obtained from a single application of bio-nitrogen and bio-phosphorus fertilizers, respectively.

This experiment was conducted to evaluate the effect of deficit irrigation on seed yield and its components of sunflower hybrids, and also identify tolerant hybrids. Twelve sunflower hybrids; Farrokh, Shams, Ghasem, Barzegar, G5 ×43, G6×43, Hysun25, Hysun36, Azargol, Sumbro, Euroflor and Sirena were evaluated under three irrigation treatments; normal irrigation (60 mm), mild drought stress (120 mm) and severe drought stress (180 mm) evaportation from Class A Pan, using split plot arrangements in randomized complete block design with three replications in Islamabad Gharb research station, Iran in 2012 and 2013 cropping seasons. Irrigation treatments were assigned to main plots, and sunflower hybrids were randomized in sub plots. Results of combined analysis of variance showed that irrigation treatments had significant effect on growth duration, stem diameter, head diameter, seed per head, 1000 seed weight and seed yield, but had no significanteffect on seed oil content. Sunflower hybrids were significantly difference for growth duration, 1000 seed weight and seed yield. Interaction effect sunflower hybrid×irrigation was not significant for any of measured traits. Mean comparison showed that seed yield of sunflower hybrids was more affected by irrigation treatments than other traits, as average seed yield in normal irrigation, mild drought stress and severe drought stress were 4470, 3637 and 2832 kg ha-1, respectively. Reduction in seed yield was due to cumulative reduction in yield components such as head diameter, seed per head and 1000 seed weight. Sunflower hybrids were also different for growth duration, plant height, non-filled seed, head diameter, seed per head and 1000 seed weight. Barzegar and Sumbro hybrids had the highest and lowest seed yield (4091 and 3362 kg.ha-1, respecrively) and the the highest seed oil content was obtaind in Hysun36 hybrid (45.6%). The results showed that Barzegar hybrid had the higher seed yield in both full irrigation and deficit irrigation conditions, therefore it can be recommended to be grown under these conditions.

In order to determine tolerant oilseed rape genotypes to terminal drought stress, 13 oilseed rape genotypes including Karaj1, Karaj2, Karaj3, Talaye, Zarfam, Okapi, Licord, SLM046, Modena, WPN5, Opera, WPN2 and GKH305 were evaluated in agricultural research station of Islamabade Gharb since 2010 for two growing season. Oilseed genotypes were planted using randomized complete block design with three replications under normal and drought stress conditions so that irrigation was cut from flowering stage. Combined variance analysis showed that the effect of terminal drought stress was significant for recorded characters except oil content, the number of branches and 1000 seed weight. Results showed that mean of seed yield decreased by 20% due to drought stress so that seed yield in normal and terminal drought stress conditions was 4586 kg/ha and 3736 kg/ha, respectively. This reduction was because of drought stress effect on yield components i.e. pods per plant and seed per pods. Genotype GKH305 had the highest seed yield with 5230 and 3941 kg/ha in normal and drought stress conditions, respectively. Bi plot derived from principal components showed that GKH305, WPN5 Zarfam and had high seed potential meanwhile were tolerant to drought stress. In current study, well known genotypes namely Licord, Talaye and SLM046 had low seed yield under both conditions. Introduction Environmental stresses are the most important factors reducing the yield of agricultural products worldwide. Drought is one of the most common environmental stresses that have limited agricultural production and decrease the efficiency of using dry and dry areas. In the field of drought stress, many experiments have been carried out in the world, but in most cases, the severe interaction between the environment and the genotype, selection of drought tolerant varieties is difficult. Improvement of drought tolerant cultivars is also one of the research priorities of the country. The effect of drought stress on plant depents on genotype, length of drought period, climatic conditions and plant growth stage (Roa & Mandham, 1991). The occurrence time of drought stress is more important than severity of drought stress (Kazi et al., 2002). Rapeseed plants, which are cultivated like wheat in both dry and wet conditions, generally experience drought stress during their life cycle. In irrigated areas and areas where surface water is used for irrigation, due to the reduction of rainfall and the use of water resources for the lucrative spring crops, the amount of water is severely depleted. As a result, the intervals between irrigation periods will be long and and plants encounter with water stress during filling seeds. According to some studies, the most sensitive time for irrigation is the flowering and early flowering stage (Richard, 1978; Richard & Thrling, 1978; Richard & Thrling, 1979; Richard & Thrling, 1979b; Pouzet, 1995). the country's largest cultivation of rapeseed belongs to the northern provinces of the country due to the presence of humidity and rainfall in these areas. However, cold and temperate cold regions like Kermanshah have a good potential for growing canola. In these areas, one of the main problems of canola cultivation is the lack of proper rainfall during the flowering stage of rapeseed and later. In these areas, rapeseed farmers who, in addition to canola, cultivate corn or wheat, canceled the canola irrigation in April, and irrigate wheat and corn, and the cut off of irrigation of canola at flowering and seeding time caused Stress and reduction of canola production. Therefore, identifying genotypes tolerant to late season drought stress in rapeseed is of great importance. In this study, in addition to investigating the effects of drought stress on yield and yield components of rapeseed, the most resistant genotypes to late drought stress were identified.

Breeding and production of drought tolerant cultivars for arid and semi-arid area is very important. The present experiment was carried out to evaluate the effects of drought stress on seed yield and yield components of oilseed rape as well as identification of high yielding and drought stress tolerant genotypes. Eighteen new winter oilseed rape lines and commercial cultivars were evaluated under three moisture conditions in two cropping seasons (2014-2016) in agricultural research station of Islamabad-e-Gharb, Kermanshah, Iran. The three moisture conditions included: full irrigation, irrigation withhold from the flowering and from silique development stages. Results showed that among the yield components, numbers of seeds per silique and 1000-seed weight were significantly affected by drought stress. The reduction in 1000-seed weight under irrigation cut off from silique development stage and flowering stage was 12.8% and 24.4%, respectively. Cumulative reduction in yield components under drought stress conditions caused a significant decrease in grain yield by 32.3% and 41.3%, under irrigation cut off from silique development and flowering stage, respectively. Correlation analysis showed that there was a weak relationship between yield in full irrigation and drought stress conditions, therefore, using drought tolerance indices to screen genotypes with high yield potential and drought stress tolerant is essential. Three dimensional diagrams based on seed yield in full irrigation condition, irrigation cut off condition from silique development stage and STI showed that genotypes GKH2624, GKH3705, Nima, Neptune, GKH0224 and HW118 were located in group A, while under irrigation cut off condition from flowering stage genotypes GKH2624, GKH3705, Nima, Neptune, GKH0224, HW118, Wpn6 and L155 were classified in group A. In general, according to biplot derived from principal components analysis and 3-D graphs, under severe drought stress (irrigation cut off from flowering stage), genotypes WPn6, HW118, Nima and GKH2624 were identified as drought tolerant genotypes with high yield potential.

Nima variety, is resulted from the selection and purification of single plants in segregating generations derived from the cross Okapi´Modena. Single plants in F2 and their segregating generations were cultivated for five consecutive years until pure-lines were obtained in F6 generation. Selected pure lines were evaluated in a preliminary yield trial conducted in Hamedan in 2008-09. The result showed that seed yield of line SW102 (Nima) was 7% higher than Okapi (check cultivar). The study of selected lines in Karaj, Hamedan, Arak, Khosroshah near Tabriz and Islamabad-e-Gharb during 2009 and 2010 showed that seed yield of line SW102 (Nima) was 18% higher than Okapi. Based on stability parameters of environmental coefficient of variation and mean and variance of ranks for grain yield, SW102 had a good yield stability across different environments in all experinments. Evaluation of resistance to common oilseed rape diseases in Iran indicated relative resistance of SW102 to blackleg and sclerotinia diseases. Results of on- farm trials in Hamedan in 2012 showed that SW102 with grain yield of 4983 kgha-1 produced the highest seed yield. Results of on- farm trials in Isfahan showed that grain yield of SW102 and Okapi under drought stress decreased 13.4 and 23.6%, respectively, compared to normal irrigation. Based on desirable characteristics of line SW102 such as high grain and oil yield, good adaptability, relative tolerance to terminal drought stress and resistance to blackleg and sclerotinia stem rot compared to Okapi (check), this line was released as Nima and is recommended for cultivation in cold and moderately cold regions of Iran.

Sunflower hybrid cultivars which have been improved and released in Iran are categorized in two early and late maturity groups. Early mature hybrids are low yielding while late matures have problems of limitation in growing season, higher plant height and higher water requirement. So, there is a lack of mid-mature and dwarf hybrids in Iranian sunflower hybrids. New hybrid, Shams was improved by crossing between CMS line AF81-112 and restorer line RF81-82 using simultaneous selection method, self and back-crossing in offseason conditions. In the preliminary evaluation, this hybrid with seed yield equal toexotic hybrid Alstar, moderate maturity and dwarf height was identified as a promising hybrid. In regional experiments in Karaj, Khoy, Zanjan and Eslam Abad seed yield of Shams (4067 kg ha-1)was equal to the exotic hybrid Hysun33 while it was also earlier and shorter than other checks. In adaptability evaluations, its seed yield was equal to Hysun33 and also it was earlier and shorter than Azargol and Hysun33. Under on-farm trials Shams was superior to check varieties in Kermanshah, Mazandaran and west Azarbayjan provinces. This hybrid had a higher seed yield compared to Farrokh and Ghasem hybrids under drought stress condition. Shams and its restorer line were resistant against powdery mildew under greenhouse condition. Shams hybrid considered as a stable and superior hybrid with an average seed yield of 3.5 tons ha-1 had a similar seed yield to those of exotic hybrids, higher yield compared to early mature hybrids of Ghasem and Farrokh and also lower plant height, moderate maturity and suitable capitule shape compared to the late mature hybrid Azergol. This hybrid was released as a new sunflower cultivar for spring cultivation in the temperate and cold regions and for summer cultivation in the temperate regions of Iran in 2017.

To evaluate the effects of deficit irrigation and super absorbent application on physiological traits and seed yield of new sunflower hybrids, a field experiment was conducted in split plot factorial layout based on randomized complete block design with three replications in Agricultural Research Station of Islamabad-e-Gharb, Iran, during cropping seasons 2011 and 2012. Treatments were irrigation levels including; normal irrigation (irrigation at 25% soil moisture depletion of field capacity), irrigation at 50% soil moisture depletion of field capacity (moderate drought stress), irrigation at 75% soil moisture depletion of field capacity (severe drought stress) as main plots and sunflower hybrids (Farokh, Ghasem and Shams) along with super absorbent application (0, 100 and 200 kg.ha-1) as subplots, were arranged in factorial layout. Results of combined analysis of variance showed that the interaction effect of deficit irrigation´hybrids on all plat traits and super absorbent´hybrids on all plant trraits (except for osmotic adjustment and cell membrane stability) and deficit irrigation´super absorbent o all plant traits (except for seed yield and cell membrane stability), were significant. Under severe drought stress condition, Farokh hybrid with 3071 kg.ha-1 was superior compare to Shams and Ghasem hybrids (with 2710 and 2601 kg.ha-1, respectively). Under severe drought stress codition, the application of super absorbent increased relative water content, free proline, proteins and soluble sugars content in sunflower hybrids, but reduced osmotic adjustment. It concluded that the application of super absorbent may relatively mitigate the adverse effects of drought stress on physiological traits of sunflower. Under drought stress condition, Farrokh hybrid along with application of super adsorbent (200 kg.ha-1) was superior in all plant traits compared to other hybrids.

To evaluate the effect of deficit irrigation on agronomic characteristics of new sunflower hybrids and to determine drought tolerant cultivars, an experiment was conducted based on a randomized complete block design (RCBD), with three replications during 2013–14 at the Agricultural Research Station of Islamabad-e-Gharb, Kermanshah, Iran. In this experiment, four new hybrids of sunflower (Farokh, Shams, Ghasem and Barzegar) were evaluated in three irrigation regimes (full irrigation, mild stress and severe stress by supplying 100, 75 and 50% of the crop water requirement). Results of combined analysis of variance showed that the effect of irrigation regime and genotype on all traits including days to flowering and physiological maturity, seed filling duration, head diameter, number of seeds per head, plant height, seed yield, biological yield and harvest index was significant (p≤0.01). The interaction of irrigation regime and genotype on all traits (except for the number of seeds per head) was significant. The results of the mean comparison showed that the seed yield of medium maturing hybrids (Shams and Barzegar) in all three irrigation regimes was higher than the early maturing hybrids (Farrokh and Ghasem). The highest seed yield (5007 kgha-1) was obtained in Barzegar hybrid with full irrigation, while Ghasem hybrid produced the lowest seed yield (1859 kgha-1) under severe stress conditions.

In order to evaluate oil yield stability in oilseed rape genotypes and genotype´environment interaction, 22 oilseed rape genotypes were evaluated using RCBD design with 4 replications in Agricultural Research Station of Islam Abad-e-Gharb during 3 cropping seasons in normal and delayed sowing date conditions. Combined variance analysis showed that genotype, environment and genotype´environment interaction were statistically significant. Proportion of environment effect followed by genotype´environment interaction was so greater than genotype effect. Based on biplot of two first genotype´environment interaction components, that explains proportion of oilseed rape genotypes in genotype´environment, genotypes Parade, Kristinia, Goliath, Shiralee, Kimberly and Elect were located next to center of biplot so that had the least proportion for the Genotype´Environment effect and were stable from the viewpoint of oil production. AMMI stability values (ASV) of genotypes confirmed the above mentioned results. Hyola401 and Zarfam were located away from the center of biplot so that were unstable genotypes for oil production. Biplot display indicated that environments E1, E3 and E4 had the most scores for genotype´environment interaction whereas E2 had the least proportion in genotype´environment interaction effect. Dissimilarity in ranking of selected genotypes from the viewpoint of oil yield based on other stability parameters suggests that it would be better using of numerous stability parameters to reliable and accurate selection of stable genotypes.

Current study was conducted to determine suitable plant density for new sunflower hybrids in second cropping. For this purpose, response of four new sunflower hybrids Barzegar, Ghasem, SHF81-90 and Farrokh to plant densities 8, 10, 12 and 14 plantm-2 was studied using factorial experiment based on randomized complete block design with four replications in Islamabade-e-Ghard Reseach Station during 2011 and 2012 cropping seasons. Results of two years variance analysis showed that plant density had significantly effect on all measured traits except harvest index. Four hybrids were also significantly different for all traits except seed number per head and harvest index. Interaction effect between plant density and hybrids was statistically significant only for 1000-seed weight. Seed yield was increased with increasing plant density, so that seed yield in 8, 10, 12 and 14 plantm-2 were 3555, 4043, 4550 and 5167 kgha-1, respectively. Among hybrids, Barzegar having more growth duration, had more seed yield (4638 kgha-1) compared to SHF81-90, Farokh and Ghasem with 4102, 4447, and 4128 kgha-1, respectively.

To evaluate and determine suitable soybean lines for second cropping in moderate cold regions of Kermanshah, an experiment was conducted using nine soybean genotypes in a split plot based on an RCBD with three replications for two cropping seasons (2012-2013). In this study two planting dates of May 22 and July11 were as the main plot and soybean genotype were as sub plot. The results of combined analysis of variance revealed that planting date effect was significant for traits such as days to flowering and physiological maturity, plant height and pods per plant and grain yield. In addition, the results indicated that there were significant differences among genotypes for all traits under study with the exception of pods per plant and plant height. Planting date×genotype effect was significant only for seed oil and protein content. Three Genotypes viz. Linford, L17 and Williams had the high seed yield at planting dates with 3249, 3255 and 3186 kgha-1 for the first planting date and 2980, 2817 and 2695 kgha-1 for the second planting date, respectively. Based on the obtained results, genotypes such as Boutny, M7, M9 and LH-2500 with short growth duration and rather acceptable seed yield could be planted as a second cropping in temperate cold regions of Kermanshah.

Sunflower hybrids derived from crossing between four restorer lines and eight CMS lines were evaluated to access new sunflower hybrids and evaluate combining ability of the sunflower CMS and restorer lines in 2012. Restorer lines were RN-3، RN-137، R-864 and R-217 and CMS lines were CMS 19، CMS 51، CMS 156/1، CMS 456/2، CMS 522/2، CMS 1052/1، CMS 60/30 and CMS 1221/1. Results showed that hybrids CMS19×R217، CMS1221/1×R137 and CMS19×R137 had the highest seed yield (7008، 5545 and 5526 kgha-1، respectively). Hybrid farrokh (check) with 5412 kgha-1 located in the forth rank. Combining ability variance analysis of line × tester showed that restorers and CMS lines effect، general combining ability، was significant for the most evaluated traits. Restorers R137 and R864 and CMS19 had the highest positive general combining ability for seed yield. Interaction effect between restorers and CMS lines، specific combining ability، was significant for days to flowering، end of flowering، days to physiologic maturity، head diameter، 100 seed weight and seed yield. The highest specific combining ability for seed yield belonged to hybrids CMS19×R217 and CMS 456/2× R217..

The present study was conducted to investigate the terminal drought stress effect on yield and its components in oilseed rape and to identify drought tolerant genotypes with high yield potential. Thirteen oilseed rape genotypes including Karaj 1، Karaj 2، Karaj 3، Talayeh، Zarfam، Okapi، Licord، Slm046، Modena، WPN5، Opera، WPN2 and G. KH305 were evaluated under optimum and terminal drought stress conditions using a randomized complete block design with three replications at the Agricultural Research Station of Islamabad-e-Gharb in 2010-2012 cropping seasons. Combined analysis of variance showed that the effect of terminal drought stress was significant for recorded characters except oil content، the number of branches and 1000 seed weight. The mean seed yield of genotypes was decreased by 20% in response to drought stress so that seed yields in optimum and terminal drought stress conditions were 4586 kgha-1 and 3736 kgha-1، respectively. Seed yield reduction in drought stress condition was associated with reduction in seed yield components i. e. pods per plant and seed per pods. Due to favorable climatic conditions in the 2010-2011 cropping season، seed yield and it’s components were higher than those in the 2011-2012. Oilseed rape genotypes were significantly different for recorded traits except oil content. Genotype G. KH305 had the highest seed yield of 5230 and 3941 kgha-1 in optimum and drought stress conditions، respectively.