کلزا

This study was conducted to evaluate the impact of delayed planting of native plants on weight of 1000-seed, the percentage of normal and abnormal seedlings, percentage of hard seeds, mean time germination (MTG), Coefficient Velocity Germination (CVG) and Mean Daily Germination (MDG) of ten cultivars of spring Oilseed rape in form of Factorial experiment (2 × 10) in complete randomized design with four replications in the Seed and Plant Certification and Registration Institute (SPCRI) of Karaj during 2022. Treatments were seeds from planting native plants on common Sowing date (the fifteenth in the Persian month Mehr) and Delayed planting (the fifteenth in the Persian month Bahman) and ten cultivars of spring Oilseed rape (RGS003, Sarigol, Hyola401, Hyola420, Hyola330, RGS006, RG4403, RG405/03, RG405/02 and RGAS0324. The results showed that trait said in two Sowing dates have significant difference together on α=0.01. between of seedling of Cultivars of Oilseed rape in terms of all traits studied except trait of percent of hard seeds that was significant on α= 0.05, remaining traits were significant on α=0.01. As well as the interaction of planting ten Cultivars in all traits except two traits of thousand seed weight and percentage of hard seeds, were significant on α=0.01. comparison of mean interaction impact of Sowing date × cultivar, showed that RGS003 cultivar on common Sowing date and Hyola401 cultivar on delayed planting than other cultivars have better Seed vigor and germination indexes.

Uptake and use efficiencies of phosphorus and some other nutrients affected by rate of phosphorus fertilizer and bio-fertilizers application. This experiment carried out to evaluate the effect of chemical and biological phosphorus fertilizers on the phosphorus uptake and use efficiency in rapeseed in a factorial based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture, Yasouj University, in 2019. The first factor included zero, 25, 50, 75, 100, and 125 kg ha-1 of phosphorus and the second factor included phosphorus biofertilizer containing Pseudomonas and its non-use. Phosphorous increased the uptake of nitrogen, phosphorus, and potassium. The highest yield was obtained from 125 kg of phosphorus and phosphorus biofertilizer. With the consumption of 125 kg of phosphorus and biofertilizer, the highest phosphorus use efficiency and remobilization was achieved. The highest phosphorus harvest index was obtained from the applying 50 kg of phosphorus and no biofertilizer, and the highest phosphorus utilization efficiency was obtained from the applying 50 kg of phosphorus along with biofertilizer. Generally, using biofertilizer with phosphorus increased nutrients uptake and seed yield. In traits such as grain yield, grain and shoot phosphorus content, there was no significant difference between the application of 50 kg of phosphorus + bacteria with the application of higher levels of phosphorus fertilizer alone, therefore, biological fertilizer can be substituted a significant part of chemical phosphorus fertilizer.

Canola (Brassica napus L.) is an oilseed crop, which due to the high percentage and quality oil, extending of its cultivation is of interest. Nitrogen is one of the most important nutrients and the key factor to achieve optimal yield in rapeseed. Considering nitrogen leaching in the soil and resulted environmental pollution, the use of biofertilizers, especially nitrogen-fixing bacteria, play an important role in enhancing nutrient uptake and nitrogen use and uptake efficiencies. Therefore, the aim of this research was to investigate the improvement of absorption of macronutrients and nitrogen efficiency indicators under the influence of chemical and biological nitrogen fertilizer management. A field experiment as split plots based on a randomized complete block design with three replications was conducted at the research station of the Faculty of Agriculture, Yasouj University located in Deshtrum in 2019. The main factor was nitrogen fertilizer at 6 levels (zero, 25, 50, 75, 100 and 125 kg ha-1 of pure nitrogen from the urea source) and the sub factor was biofertilizer containing Azotobacter and Azospirillium bacteria at two levels (application and non- application). The uptake of nitrogen, phosphorus and potassium nutrients in seeds and shoot was measured and the nitrogen efficiency indices were calculated. The highest seed nitrogen, phosphorus and potassium percentage obtained from the combined application of nitrogen fertilizer + bacteria. The combined application of chemical and biological nitrogen fertilizer increased grain yield. The highest seed yield (8790.60 kg ha-1) was obtained in the treatment of 125 kg ha-1 of nitrogen and the application of biofertilizer. The nitrogen use efficiency decreased with the increase of nitrogen levels, and the maximum (40.92 kg ha-1) was obtained from the treatment of no application of bacteria and also nitrogen. The nitrogen uptake efficiency increased significantly with the use of nitrogen fertilizer and the use of bacteria. The maximum nitrogen remobilization (89.79%) was obtained from the application of 125 kg ha-1 of nitrogen and no application of biofertilizer, and the lowest was obtained from the treatment of no application of nitrogen and application of biofertilizer (74.46%). Considering the superiority of the 125 kg ha-1 of nitrogen along with biofertilizer in terms of seed yield and percentage of absorbed nutrients, it seems that these amounts of nitrogen fertilizer with the use of biofertilizer are recommendable to achieve proper yield in the examined and also similar areas. Also, the results showed that for most of the investigated traits, applying biofertilizer could reduce the consumption of chemical nitrogen fertilizer by supplying some part of the nitrogen (ca. 50 Kg/ha) needed by canola.

Oilseeds are the second largest food reserves in the world after cereals. Rapeseed cultivars were drought sensitive during germination and during pod growth stages and the greatest increase in damage occurs simultaneously with the lack of water during the growth of newly established young seedlings. Seeds of 6 rapeseed cultivars (including: Kodiak, Jerry, Brutus, Jacomo, Julius, Traviata) were tested in the research greenhouse of Gorgan University of Agricultural Sciences and Natural Resources as factorial experiments with a completely randomized design with 4 replications. Drought treatment levels including 6-, 4-, 2-, 1-, 0.5-bar were irrigated according to the equivalent amount of water required in the repetitions of each treatment. Sampling was performed to calculate yield index and related traits, oil percentage, TBARM biochemical index, chlorophyll and proline content as well as random sampling to perform molecular studies and study of gene expression. The results showed that with increasing stress levels in rapeseed cultivars, grain yield and related traits, oil content and chlorophyll content decreased. It was also observed that with increasing stress, TBARM and proline index were produced to a greater extent. In the case of ACCase and SAD genes, the highest gene expression was related to Traviata cultivar at 4-bar stress level and also the results obtained from P5CS1 and PDH genes showed that with increasing drought stress in rapeseed cultivars, gene expression was also increased. There was an increase in them.

False chinch bug (Nysius cymoides (Hem: Lygaeidae)) is one of the most important pests of canola in Iran and causes  significant damage to this crop annually. In order to evaluate the resistance of canola cultivars to this pest, 12 cultivars included Arshitect, Okapi, Nafis, Atura, Nima, Gabriella, Koodiak, Garo, Brotus, Rohan, Deffusion, and Traviana were studied in a completely randomized design in the research farm of the Faculty of Agriculture of Kurdistan University in 2020 and 2021 years.  In this study several parameters related to the false chinch bugs (Weight and population density of the pest) and several plant parameters (secondary branches number, diameter of the main branch, pod length, flowering branch length, seeds number per pod, 1000 seed weight and seed yield) were evaluated. The results of data analysis showed that there was significant difference between cultivars in terms of some parameters including seed weight, plant length, pod length, number of seeds per pod, 1000 seed weight, and yield at a 5% probability level. Also according to the multivariate analysis of variance, there was no significant difference between the type of trap and the type of cultivar, but there was a significant difference between the types of traps. In total, using cluster analysis by Ward's method and based on Euclidean distance, 12 studied cultivars were divided into four groups: resistant, semi-resistant, susceptible, and semi-susceptible.

Salinity is one of the major abiotic stresses and the most limiting factor in agricultural production worldwide, affecting the growth, development, and final yields of crops. Rapeseed is one of the most important sources of oilseeds in the world, and its seeds contain more than 40% of oil. Moreover, the meal obtained from oil extraction has more than 35% protein, hence it currently ranks third among oil crops in the world after soybean and oil palm, making it necessary to identify the genotypes that tolerate salinity stress. The development and improvement of rapeseed cultivars with salinity tolerance and acclimation offer promising prospects for improving sustainable production in this area. Therefore, the current study aimed to investigate the responses of rapeseed genotypes to salinity stress through analyses of agronomic and biochemical traits.

The genetic diversity between rapeseed lines in terms of agronomic, morphological, and physiological traits in saline soils was investigated in an experiment based on a randomized complete block design with 17 autumn rapeseed genotypes with three replicates in the research farm of East-Azarbaijan Agricultural and Natural Resources Research and Education Center. The measured traits were plant height, the number of fertile pods, number of seeds per pod, pod length, pod area, plant growth rate, 1000-seed weight (TSW), seed yield, oil content, and oil yield. The relationships between yield, yield components, and morphological traits were explored using the analysis of variance (ANOVA), comparison of averages, correlation analysis, cluster analysis, and biplot to understand the relative importance of traits affecting the yield of the studied genotypes.

The studied genotypes were significantly different from each other in pod length, pod area, number of fertile pods, number of seeds per pod, plant growth rate, seed oil percentage, plant height, TSW, grain yield, and oil yield. However, there were no significant differences between the studied genotypes in terms of harvest index and number of actual pods to potential pods. According to the mean comparisons, genotypes 5, 11, and 15 can be introduced as salinity-tolerant lines, and genotypes 2, 4, 6, 9, and 12 can be considered salinity-sensitive lines. According to the other traits, genotype 11 produced a high pod length, number of fertile pods, oil percentage, and oil yield, genotype 5 had a high growth rate and oil percentage, and genotype 15 presented a high height and number of fertile pods. According to the cluster analysis, the second and third groups contained tolerant and susceptible genotypes, respectively. The genotypes in the second group had the highest percentage of positive deviation from the overall mean for grain yield, plant height, harvest index, seed oil percentage, pod length, pod area, and number of fertile pods. Based on the biplot analysis, Karaj 8 and 14 genotypes had a strong relationship with the number of  fertile pods, number of seeds per pod, pod length, pod area, and plant growth rate. Based on the obtained results, the plant height, TSW, seed yield, and oil content traits were closely correlated with Karaj 5, 7, 11, 10, and 15 genotypes. Based on the results of correlation analysis, the correlation coefficient of seed yield was positive and significant for three traits, i.e., plant height, oil percentage, and number of fertile pods, and the highest correlation coefficient (r = 0.879) was obtained for seed yield with seed oil percentage. Positive and significant correlations were measured for the number of seeds in pods with pod length (r = 0.699), pod area (r = 0.555), number of fertile pods (r = 0.678), and number of actual pods. Therefore, genotypes characterized by longer and more abundant pods play a crucial role in improving seed quantity, a key component of grain yield in saline environments. Consequently, the size and number of pods per plant serve as indicators of high-yield potential under such conditions. Based on the results of the principal component analysis (PCA), the first and second components had the highest relative variances, accounting for 44.66% and 31.22% of the total variance, respectively. Together, these two components accounted for 75.88% of the total variance. Factor loadings showed that traits such as number of fertile pods, seed yield, oil yield, and seed oil content had the highest factor loadings in the first component. Similarly, the plant growth rate had the highest factor load in the second component among all the studied traits. Cluster analysis divided the genotypes into four groups, and its dendrogram showed that all the studied genotypes were divided into four separate groups based on all the measured traits. The first group comprised three Karaj 1, 13, and 16 genotypes, the fourth group (like the first group) contained three Karaj 5, 11, and 15 genotypes, and the third group had five genotypes, namely Karaj 3, 7, 8, 10, and 14. The remaining genotypes were assigned to the second group.

The results of the present study demonstrate acceptable genetic diversity among rapeseed genotypes in terms of the evaluated traits in saline lands. This shows the importance and the possibility of using these genetic resources to achieve promising and superior genotypes in breeding programs.

To evaluate the response of different rapeseed cultivars to cut-off irrigation at the end of season on seed fatty acids, glycosinolates and agronomic characteristics of cultivars, a split plot experiment based on randomized complete block design with three replications in Moghan Research Center ,was conducted during 2014-2016 cropping season.Experimental treatments were levels of irrigation as the main factor in three levels, normal irrigation (control) according to plant needs and local customs, low irrigation stress in the form of irrigation cutting at the plowing stage and irrigation cutting at the flowering stage and Rapeseed cultivars as sub-factors in 11 levels included 003RGS, Sarigol, Zafar, Dalgan, Julius, Jacomo, Jerry, Jerom, Zabollo, 401Hyola, 4815 Hyola. In this study, the yield and yield components of rapeseed were not significantly affected by water stress after flowering and pods and only post-flowering stress reduced the number of seeds per pod by 4.7%. Biomass also decreased to 2.9% under the influence of stress. Despite the above results, the properties of rapeseed oil were strongly affected by water deficite. The amount of palmitic acid due to stress decreased to 32.6% (at Jerome cultivar), while the amount of linoleic and, erosic acids and glucosinolates under stress increased to 84.4%and 148.7% (at Zafar cultivar) and 118.7% (at Jerome cultivar). In this study, the highest grain yield  sa2986 and 2981 kg / ha was obtained in Julius and RGS003 cultivars. In these cultivars, all three components of yield as , yield of number of pods per plant, number of seeds per pod and 1000-seed weight were higher than with comparison of other cultivars.There was a high difference between cultivars for palmitic, lithinolenic, linoleic, oleic acids and glucosinolate. In general, Zafar and , Julius cultivars were the best cultivars due to their high  yield and oleic and linoleic acids content.

Oilseed rape is one of the most important sources of vegetable oil in the world, and its seed contains more than 40% of oil, and the meal obtained from oil extraction has more than 35% of protein, and currently it ranks third among oil plants after soybean and oil palm. in the world. The existance of environmental stresses, such as drought stress, causes a significant decrease in oilseed rape yields. Therefore, breeding for drought tolerance is very important, and creating high yielding and early maturing or drought tolerant cultivars is one of the important goals of breeders. The purpose of this study was to determine the best general and specific combiners and the amount of heterosis compared to the superior parent in spring rapeseed using line×tester analysis in two conditions of normal irrigation and drought stress.

Seven high-yielding rapeseed lines were crossed with five testers with a range of early maturity in the 2018-2019. The first generation hybrids along with 12 parents (47 genotypes in total) were evaluated in the randomized complete block design with three replications in two conditions of normal irrigation and terminal drought stress (irrigation cut off at the beginning of podding stage) in the 2019-2020. The studied traits included physiological maturity date, plant height, number of pods per plant, pod length, number of grains per pod, height of the first pod from the ground, 1000-grain weight, seed yield, oil percentage and oil yield.

The results of analysis of variance in both normal irrigation and drought stress conditions showed a significant difference between hybrids for all investigated traits, which indicated a significant diversity between genotypes. In analyzing the effect of hybrids into the relevant components, the interaction effect of line × tester was significant for all the traits under normal irrigation conditions and also under drought stress conditions except for the height of the first pod from the ground, and oil yield. The effect of parents versus hybrids was significant in normal for all traits except the number of seeds per pod under normal irrigation conditions and except for plant height, pod length and number of seeds per pod in drought stress conditions, which indicates the existence of heterosis for these traits. For the trait of physiological maturing, among the lines, line 6 showed the highest negative general combining ability under normal irrigation and drought stress conditions, and tester 5 showed the highest negative general combining ability among the testers under normal irrigation and drought stress conditions. Tester 5 was contributed in early maturing T5×L3 hybrid under drought stress conditions. L1 and L5 in both conditions and T2, and L3 and L4 in normal irrigation conditions and T1 in drought stress conditions were identified as the best general positive and significant combiner for the number of pods per plant, and hybrids T5×L1, T1× L5, T2×L4, T4×L4, T1×L7, T1×L6, T2×L7, T3×L2, T5×L7, and T4×L3 were the best specific combiner to increase the number of pods per plant in both experiment conditions. T4 was the most significant positive general combiner under normal irrigation conditions and drought stress for the 1000-grain trait. Also, regarding the positive significant specific combining ability for this trait hybrids T2×L7, T3×L7 in both conditions, and in addition hybrids T1×L7 and T5×L4 under normal irrigation conditions and hybrids T1×L6 and T3×L5 under drought stress conditions showed the highest amount. The most significant positive general combining ability in grain yield was determined to T5 and L1 and L6 in both conditions. The best significant positive specific combining ability were T2×L7 and T3×L7 in both conditions. The highest positive and significant amount of general combining ability of the amount of oil, was given to T3 and T5 and L6 in both experimet conditions, and T4 and L7 in normal irrigation conditions and L5 in drought stress conditions. T1×L6, T5×L1, T2×L5, T3×L1, T5×L3 and T4×L4 were among the best hybrids in both conditions. In normal irrigation conditions, T2×L3, T4×L3, T5×L1, T4×L6, and T5×L3 and in drought stress, T5×L1, T2×L3, T2×L4, T4×L4, T4×L3, T4×L5 and T2×L7 had the highest amount of heterosis in the positive direction for the number of pods per plant. The trait of the number of grain per pods, T2×L3, T4×L3, T5×L1, and T2×L5 under normal irrigation conditions and T5×L6, T3×L6, and T5×L3 under drought stress condition had the highest amount of heterosis.

The estimation of traits' combining ability showed that T5 and L1 and L6 were the best general combiners to increase grain yield. T3×L7 and T2×L7 hybrids were the best specific combiner for increasing grain yield under normal irrigation and drought stress conditions. Also for the 1000-seed trait, T3×L6, T4×L1, T5×L4 and T1×L1 hybrids under normal irrigation conditions and T3×L7, T1×L6, T2×L6 and T3×L3 hybrids under drought stress conditions have the highest amount of heterosis. The number of pods per plant and the number of grain per pods under normal irrigation conditions, T2×L3, T4×L3 and T5×L1 had significant positive heterosisTherefore, their parents can be suggested for hybrid varieties production programs.

The new oilseed rape cultivar Nilofar (R15), is the result of screening and purifying single plants in segregating generations derived from the cross "Symbol×Orient". During five years of consecutive cultivation, screening of single plants was continued to access pure lines using pedigree method and pure lines were selected in F4 generation. During cropping season 2008-2009, 84 pure lines were evaluated in preliminary yield trial. Results showed that Nilofar variety with a mean yield of 3352 kgha-1 had higher grain yield by 45% compared to the Okapi control variety with a mean grain yield of 1833 kgha-1. In the Value for Cultivation and Use (VCU) trial in six research stations of cold and mid cold regions of Iran including Karaj, Isfahan, Hamedan, Islam abad-e- gharb, Khoy and Arak during two cropping seasons 2009-2011, Nilofar variety with an average grain yield of 3783 kgha-1, ranked first and had 16.1% grain yield more than the Okapi. Under delayed sowing date and stopping irrigation from silique development stage in Karaj during two cropping seasons 2012-2014, Nilofar with 1986 kgha-1 and 0.62 kgm-3 in term of grain yield and water use efficiency, respectively, was superior to Okapi with 1626 kgha-1 grain yield and 0.62 kgm-3 water use efficiency. The glucosinolate content of Nilofar variety was less than 10 μmolg-1 of dry matter and the erucic acid content of the oil was less than 2%. The results of the extension research project in Kermanshah province showed that the mean grain yield of the Nilofer variety at two sites of Sarab Nilofer and Mahidasht was 4004 kgha-1, which was 14.8% higher than the Okapi control cultivar. Due to its high grain yield potential and appropriate agronomic characteristics, line R15 was released under the name of Nilofar and is recommended for cultivation in the cold and mild cold regions of Iran.

Saffar (Zabol 10b line) variety was obtained by pedigree method from Goliath×19H cross. Based on preliminary evaluation, this variety showed significant earlier maturity (13 day), in 2010-2011, compared to the other lines of canola. Based on adaptability expieriments in Zabol, Safiabad, Behbahan, Boushehr, Gorgan, Gonbad, Sari and Moghan regions in 2011-2012, its grain yield had not significant difference from control variety RGS, but had a high early maturity. The new variety had a lower rank variance which indicates the Less performance fluctuations and stability in different years and regions compared to control variety RGS. Saffar cultivar with 165 days growth period was 12 days earlier in maturity than control variety RGS in warm south and north regions. The oil content of new variety was 43.15%, which has not significant difference with control variety RGS but in terms of having higher amounts of oleic acid and lower amounts of linolenic acid, it has a better quality. The field response of new variety to stem sclerotinia disease showed good relative tolerance in the north climate, which has significant difference with control variety RGS. Based on outstanding features such as yield stability, early maturity, possibility of escaping from drought and heat in the last season, saving at least one irrigation stage and uniformity in maturity, this line was released with the name of Saffar in 2018 and recommended for late cultivation in warm areas with short growing seasons in warm south and north climate zones of the country such as the south of Kerman, Sistan and Baluchestan, Hormozgan, Khuzestan and Gorgan.

In order to identify important agronomic traits related to yield and introduce early with high-yielding cultivars in Brassica genus, 100 genotypes of six species of Brassica genus (B. napus, B. juncea, B. nigra, B. rapa, B. carinata and B. oleracea)were evaluated implementing latis square designs with two replications experiments at Sari Agricultural Sciences and Natural Resources University Research Farm during 2017-2018. The results of variance analysis showed that the studied genotypes have very significant differences with each other in terms of all agricultural traits. The results of mean comparison showed that genotypes from B. napus species has the highest yield and genotypes from B. rapa species has the shortest days to ripening with the lowest yield. The longest days to ripening was identified as genotypes from B. juncea species. The analysis of genetic correlations for all species revealed that yield of seed had a significant positive correlation with days to ripening, silique number per plant, thousand grian weight and grian number in silique. Results of stepwise regression analysis revealed that silique number per plant, 1000-grain weight, number of silique per plant and days to maturity had significantly effects on grain yield. The result of factor analysis showed three independent factors that explained 92% of the total variability, which were named ‘productivity’, ‘phenology’, and ‘thousand grian weight’, respectively. According to all three factors, B. napus, best species and Janetzika، Liragold، Hayola 401and Hayola 308 from B. napus species, were identified as the best cultivars concerning seed yield and early maturity.

Rapeseed with the scientific name (Brassica napus L.) are one of the most important oilseed crops in the world. Considering the country's increasing need to import oil and the importance of rapeseed among oilseeds plants, increasing the yield and percentage of oil is very important. Therefore, identification the traits that increase seed yield, play an important role in the success of breeding programs. Yield is a complex trait that is affected by many factors. direct selection of a variety for yield is not often very effective, so investigating the relationships between grain yield and other traits for indirect selection may be effective. In such a situation, correlations may not clarify the relationships well, therefore, multivariate statistical methods and path analysis can help in understanding the nature of the relationship between traits for direct or indirect selection and improve the efficiency of selection in breeding programs plants become useful.

In this study, eight genotypes of spring rapeseed (SPN-202, SPN-204, SPN-206, SPN-207, SPN-217, SPN-225, SPN-227, SPN-182) along with 56 rapeseed hybrids (F1) were planted in a randomized complete block design with three replications in 2019-2020 crop years in the research farm of Gorgan Agricultural Research Station. During the experiment, phenological, morphological traits, yield and yield components were recorded. The normality of the data was evaluated based on the Kolmogorov-Smirnov method. In order to understand the relationships between traits and to identify the traits affecting on grain yield, at first, correlation coefficients were estimated, then stepwise regression were done. Then, path analysis based on correlation coefficients was used to determine the direct and indirect effects of traits. Finally, all traits were grouped based on principal component analysis.

The results of analysis of variance indicate a significant difference for all studied traits at the probability level of one percent. The coefficient of variation (C.V) for the traits varied from 1.37 (physiological maturity) to 10.31 (number of sub-branches), which indicates that there is sufficient accuracy in conducting the research. The results of correlation evaluation showed that number of pod per lateral branches (0.864), number pods per Plant (0.865), number of lateral branches (0.466), physiological maturing (0.329) and number of grain per pod (0.358) had a positive and significant correlation with grain yield (P<0.01). Stepwise regression analysis showed that the traits of number of pods per plant, number of grain per pod and 1000-grain weight has a decisive role on grain yield. Based on the results of path analysis, number of pods per plant had the most direct effect (0.881) and number of grain per pod had the most indirect effect (0.053) through the number of pods per plant on grain yield. In order the results of principal component analysis, four components were able to explain 75.91% of the changes in the measured data of 64 rapeseed varieties.

Results of the path analysis showed that number of pods per plant, number of grain per pod and 1000-grain weight had a direct positive effect on grain yield. Also, the stepwise regression analysis showed that the stated traits have the highest regression coefficients. Therefore, selection for these traits can be very effective in achieving high performance

In order to investigate the effect of silica and calcium content and harvest dates on yield and yield components of rapeseed as a factorial split in a randomized complete block design with three replications in experimental farms in Aftab region of Tehran province in two cropping years 2018-2019 and 2019-2020 were implemented. Experimental factors include harvest date in three levels one week after the start of yellowing of pods, two weeks after the beginning of yellowing of pods and time of complete yellowing of pods, silica in three levels of zero (control), 3 and 6% of the source was sodium and calcium silicate at three levels of 2, 4 and 6% of the source of calcium sulfate. The results showed that the effect of year on plant height, number of pods per plant, number of seeds per pod and anthocyanin was significant and the second year had the highest amount of these traits. It was observed that the best grain yield of 2477.02 kg / ha and harvest index of 24.83% was related to harvest one week after the start of yellowing of pods and with delay in harvest, 1000-seed weight, grain yield, Biological yield and harvest index decreased and anthocyanins increased. According to the results, silica foliar application with 32.81% increase in plant height, 11.8% number of pods per plant, 31.48% number of seeds per pod, 17.2% weight per thousand seeds, 24.31% grain yield, Biological yield and harvest index and reduction of anthocyanin and electrolyte leakage were associated. The most positive effect on physiological characteristics and yield and yield components was obtained in 6% silica spray. With increasing calcium concentration, plant height, number of pods per plant, number of seeds per pod, 1000-seed weight, grain yield, biological yield and harvest index decreased and anthocyanin and electrolyte leakage decreased, the maximum positive effect on these traits in foliar application 6% calcium was observed. The results showed that silica and calcium had an additive effect on yield and yield components and the best grain yield was obtained by consuming 6% silica with 6% calcium and harvesting one week after the start of yellowing of pods.

Early vigor, stress resistance, uniformity, high yield, and breeder right protection have turned hybrid cultivar development into the most successful breeding strategy in rapeseed (Brassica napus L.). The goals of this research were to develop the first CMS based rapeseed hybrids in Iran and to evaluate their performance and fertility. The effect of different traits on yield increasing of hybrids was also studied. Seven CMS lines were crossed with R2000 (a restorer-line) and the seed yield of hybrids was tested using a randomized complete block design with three replications in 2019-2020 and 2020-2021. Three of hybrids with 4.64, 4.40, and 4.38 tons per hectare, showed considerable yield and were significantly different than Nilufar, Neptune, and Nima (3.44, 3.37, and 3.30 tons per hectare, respectively), as check cultivars. R2000×A8 demonstrated the highest heterosis (34.71%) to high-check cultivar. All hybrids obtained were normal in terms of fertility, having no male-sterile flowers. Based on the results of principal component analysis and cluster analysis, the simultaneous increase in the number of pods per plant and the thousand seed weight, together with crossing the more distant parents will lead to more high yielding hybrids. The promising hybrids with high yield and remarkable fertility could be released as new cultivars after passing adaptability and stability experiments.

In order to evaluate the tolerance of rapeseed genotypes to heat stress, an experiment was carried out in the two crop years of 2018-2019 and 2019-2020 in the experimental farm of Shahid Chamran, University of Ahvaz, Ahvaz. The experiment was conducted as a combine analysis in the frame of a randomized complete block design with three replications in two conventional sowing dates (normal conditions) and delayed planting dates (stress conditions) on 9 rapeseed genotypes (including 8 hybrids and one free-pollinating variety). The results of combine analysis of variance showed that the seed yield of the genotypes differed with each other at the probability level of 1%. Also, there was a significant difference between the environments (conventional and delayed cultivation) in both years and the year effects. The average yield of genotypes under normal and stress conditions in the first year was estimated as 3.467 and 1.667 tons per hectare and in the second year as 3.358 and 1.687 tons per hectare, respectively. The increase in yield under normal conditions in the first year compared to the second year was due to more rainfall and more suitable temperature in the first months of cultivation. In this experiment, the stress intensity was estimated at 0.51 in the first year and 0.46 in the second year, which indicated high stress intensity during two years. The delay in planting followed by heat stress caused a 48% decrease in yield per unit area in average. The results of the analysis of indices based on grain yield showed that harmonic mean indices, stress tolerance index, geometric mean productivity, and average productivity are the best indices in assessing heat tolerance in rapeseed. And these four indicators had a positive and significant correlation with performance in both normal and stressful conditions. Drawing a three-dimensional diagram based on grain yield under stress and normal conditions and the selected indices showed that Hayola 50 and Hayola 61 hybrids are more heat tolerant than other cultivars and hybrids and have higher yield stability under heat stress conditions. Therefore, for areas with heat stress at the end of the growing season, Hayola 50 and Hayola 61 hybrids are more suitable than other hybrids and are recommended for cultivation in those areas.

This experiment was carried out as split plot factorial based on complete block design with three replications during 2018-2019 cropping season in two regions including Qazvin and Karaj, Iran. Irrigation regimes including three levels of full irrigation, irrigation interruption from flowering stage and irrigation interruption from silique stage and four levels of micronutrients including zero (control), foliar application of Zn, Fe and Zn + Fe as factorial in main plot and two cultivars of rapeseed namely Sarygol and RGS300 in sub plot comprised experimental treatments. The greatest number of secondary branch per plant (7.72), number of silique per secondary branch (125.80), 1000-seed weight (5.46 g), biological yield (23760 kg/ha), seed yield (5668 kh/ha) and oil yield (5668 kg/ha) obtained in RGS300 cultivar under full irrigation and foliar application of Zn + Fe conditions that showed no significant difference with Sarigol cultivar under similar condition. In this experiment, irrigation interruption from flowering stage showed the greatest loss of seed yield in rapeseed and under water deficiency from flowering stage, foliar spraying of Zn + Fe enhanced seed and oil yield of RGS300 and Sarigol cultivars equal 107 and 153 percent in comparison with control, respectively.Integrated application of Zn + Fe as foliar application increased seed yield through improving of vegetative and reproductive growth of rapeseed plants in different irrigation regimes. Hence, combined foliar application of Zn + Fe micronutrients both with four per thousand concentrations could be recommended to enhance quantitative and qualitative yield of rapeseed under similar climatic condition

The aims of this study is evaluate AquaCrop in simulating rapeseed yield, biomass and water use efficiency under different irrigation amounts (E1, E2, E3 and E4, indicating water supply of 50, 75, 100 and 125 mm from the evaporation pan, respectivly) was performed in three cropping years (Y1, Y2 and Y3 representing the first, second and third years, respectively). In order to calibrate this model, the data collected from the first year used for calibration and data for the second and third year were used for validation. The results showed that AquaCrop had an overestimated error (MBE< 0) to simulate all three parameters studied. The accuracy of AquaCrop was excellent for simulating yield and biomass (NRMSE <0.1) and good for water use efficiency (NRMSE <0.2). The mean differences between simulated and observed yield, biomass and water use efficiency water were 0.19 t.ha-1, 0.78 t.ha-1 and 0.05 kg.m-3, respectively. Based on the results, use of AquaCrop to simulate rapeseed yield, biomass and water use efficiency is recommended.

Canola is one of the most important oilseeds that plays a major role in providing human edible oil and in this regard, it is in the third place after soybean and palm oil. There are many strategies to improve growth, yield and precocity in plant species including rapeseed. Seed priming is a pre-planting strategy that is very effective in improving germination, grow rate, seedling establishment and early maturity. As a result, considering the importance of increasing the quantity and quality of rapeseed and the positive effects that treatment has on improving germination, increasing yield and early maturity in rapeseed, In this study, investigating the effect of seed priming by gibberellin and salicylic acid on the characteristics of germination, growth and seed yield of canola was done.

In this research, a factorial experiment was conducted in a randomized block design with three factors. The first factor of genotype (Lord and Hayola 308), the second factor of salicylic acid (zero, 750, 1500 and 2250 μM) and the third factor of gibberellin (zero, 750, 1500 and 2250 μM) with three replications in research greenhouses of University of Agricultural Sciences and Resources Natural Sari was done in 1397. Canola seeds were immersed in the solution of the mentioned salicylic acid and gibberellin treatments for 24 hours at a temperature of 25 degrees Celsius. After passing the desired period, the seeds were washed with distilled water and completely dried on filter paper, which were immediately cultivated after drying. Germination percentage, first day of emergence, last day of emergence, time spread of emergence, day to maturity, 1000-seed weight, number of pods per plant, plant height, pod length, number of seeds per pod and yield were measured. At the end, all statistical analyzes of the data obtained from this experiment, after ensuring their normality, were performed using SAS and SPSS software.

The results of analysis of variance showed that seed priming by salicylic acid and gibberellin treatments had a significant effect on all traits except pod length at the level of one percent. The interaction of genotype with salicylic acid and the interaction of genotype with gibberellin were significant for all traits. The interaction of salicylic acid with gibberellin and the triple interaction of gibberellin with salicylic acid with genotype were significant for all traits except pod length. The results of mean comparison showed that the use of seed priming of salicylic acid and gibberellin, with increasing germination percentage, reducing the range of emergence and decreasing the day to maturity caused early ripening in rapeseed. In addition, by increasing the yield components such as number of seeds per pod, number of pods per plant, 1000-seed weight, height and length of pods, also increased grain yield. The results also showed that the combined application of 1500 μM levels from both treatments (salicylic 1500 × gibberellin 1500) has the greatest effect on increasing yield components and grain yield, so that grain yield in Lord genotype from 7.5 (gram per pot) to 12.1 (gram per pot) And in Hayola 308 genotype increased from 4.1 (g/pot) to 6.89 (g/ pot).

In general, the results showed that among the different concentrations of treatment, lower concentrations of these treatments were more effective in inducing prematurity and increasing yield. And among the cultivars used, Lord genotype has a higher but late yield, which can be solved by treating the problem of late maturity and as the best genotype in terms of early maturity and high yield under the influence of treatments, especially at the level of 1500 salicylic acid × Gibberellin introduced 1500 μM

Canola (Brassica napus L.) is one of the important oil plants in temperate regions, which has great value for humans and livestock as a producer of oil and meal. Phosphorus plays an important role in improving the quality and quantity of oilseeds, including rapeseed. Sufficient sources of phosphate are needed by the plant for earlier development and rooting and more foliage production in a short period of time. Considering the stabilization of phosphorus in the soil, the increase in the price of chemical fertilizers and environmental pollution, the use of biological fertilizers, especially the types of phosphorus-dissolving bacteria, play an important role in solving these problems. Therefore, the objective of this research was to investigate the role of phosphorus biofertilizer containing Pseudomonas fluorescens bacteria in improving the quantitative and qualitative yield of canola under the influence of chemical phosphorus fertilizer management.

A factorial field experiment was conducted based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture of Yasouj University located in Deshtrum region in 2019. The first factor was triple superphosphate fertilizer at 6 levels (zero, 25, 50, 75, 100 and 125 kg/ha of pure phosphorus) and the second factor included phosphorus biological fertilizer containing Pseudomonas fluorescens bacteria at two levels (application and non-application). The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. Yield components, seed and biological yield, and seed oil and protein were evaluated.

The results showed that phosphorus and bacteria chemical fertilizers had a significant effect on all investigated traits. The interaction of phosphorus chemical fertilizer and bacteria was also significant on all investigated traits except harvest index. The highest plant height (124.93 cm), number of lateral branches (4), leaf chlorophyll index (74.20), seed yield (5887 kg/ha) and biological yield (19411.4 kg/ha) were obtained in the treatment of 125 kg/ha of phosphorus and bacterial application. Also, with the consumption of 125 kg/ha of phosphorus fertilizer and the use of bacteria, the highest percentage and oil yield was obtained. Also, the results showed that there is no significant difference between the treatment of application of 50 kg of phosphorus fertilizer + bacteria and the treatments of application of higher levels of phosphorus fertilizer (75, 100 and 125 kg) alone.

Considering the superiority of 125 kg of phosphorus fertilizer along with bacteria in terms of grain yield, oil percentage and oil yield, it seems that these amounts of phosphorus fertilizer as well as the use of bacteria can be used to achieve proper yield in the experimental and also similar areas. Also, the results show that using bacteria can reduce the consumption of phosphorus chemical fertilizers.