آرمان آذری

In order to investigate the effects of different Pseudomonas bacterial strains, including fluorescens, Chloraphis and Putida strains, on the morpho-physiological characteristics and performance of Sante variety potato under drought stress in the Jiroft region, an experimental study was conducted in the form of a split-plot design with a randomized complete block design with three replications for two years, 2019–2020 and 2020–2021. The main factor of the experiment consisted of three levels of drought stress (40, 65, and 90 mm of evaporation from the evaporation class A pan), while the sub-factor included four levels of Pseudomonas bacterial strains (control, strain T12 (Pseudomonas fluorescens RO7), strain T13 (Pseudomonas putida RO3) and strain T17 (Pseudomonas chlororaphis RO1). The results showed that the applied drought stress treatments had no effect on the chlorophyll a content. The use of Pseudomonas bacteria strains increased the content of chlorophyll b and total chlorophyll (a+b). The carotenoid content of leaves at 90 evaporation from the Class A pan with the application of bacteria strain T17 showed the lowest amount compared to the treatment without bacteria and strains T12 and T13. Application of bacteria strain T13 showed the highest superoxide dismutase (SOD) enzyme activity at different drought stress levels. There was no significant difference in peroxidase enzyme activity between different Pseudomonas bacterial strains and the treatment without bacterial application at various drought stress levels. The highest catalase enzyme activity in the leaves was observed in the application of Pseudomonas bacterial strains T12 and T17. The application of Pseudomonas bacterial strains led to a significant increase in shoot dry weight, tuber dry weight, and total tuber weight in potato plants compared to the treatment without bacterial application at all drought stress levels.

In order to study the effect of cold stress on some physiological characteristics of nine ecotypes of grass pea, a factorial split plot experiment based on completely randomized design with two factors and four replications was carried out in growth chamber. The first factor was cold treatment at two levels (25 and -3˚C) and the second factor was ecotype at nine levels collected from local areas named Bam, Sirjan, Torbat Heydariyeh, Baft 1 (Kiskan area), Baft 2 (Bidgerdoyeh area), Shiraz, Kuhbanan, Rabar and Bardsir. Traits measured in this experiment included content of soluble sugars, proline, starch, chlorophyll a, b and total chlorophyll, as well as the activity of antioxidant enzymes. The results showed that in all ecotypes with decreasing temperature from 25 to -3 degrees the content of soluble sugars, proline, ion leakage and the activity of catalase and peroxidase enzymes increased whereas the content of starch and chlorophyll a, b and total decreased. Significant variation was observed between ecotypes in terms of cold stress tolerance. In Baft 2 and Bardsir ecotypes, proline content was higher than other ecotypes. Also, the highest soluble sugar content was related to Baft 2 ecotype and the highest catalase activity was related to Bardsir ecotype. In addition, these ecotypes had higher survival score. Based on the results of survival score, Baft2 and Bardsir ecotypes showed the highest resistance to cold stress and Bam, Shiraz and Sirjan ecotypes showed the lowest resistance.

The present study tries to quantify germination response of Guar (Cyamopsis tetragonoloba) to temperature and water potential. Performed in Vali-e-Asr University laboratory in 2020, it is a completely randomized design in a factorial arrangement with four replications. It aims at quantifying the rate of Guar germination in response to temperature, and water potential. The seeds have been germinated at seven temperatures (5, 10, 15, 20, 25, 30, and 35°C) and six water potentials (0, -0.2, -0.4, -0.6, -0.8, and -1 MPa). The results reveal that the Beta function is suitable for describing the response of seed germination temperature, and water potential. Under different water potentials, base, optimum, and maximum temperatures have been 7.3-12°C, 22.1-25.8°C, and 32.2-36°C, respectively. The hydrothermal time parameters are 268.3 bar °C h, -1.103 MPa and, 8.36°C for ɵHT (hydrothermal time constant). The data obtained from these models can be used to establish and manage guar for cultivation in different areas.

In order to investigate the effects of salicylic acid and thiourea on yield and morphophysiological characteristics of safflower under drought stress, an experiment was conducted as split plot factorial based on randomized complete block design with three replications. The main factor was three levels (80 (non-stress), 110 and 40mm evaporation from evaporation pan) and sub-factor was three levels of thiourea (zero, 500 and 1000ppm) and two levels of salicylic acid (zero and 1mM). The highest plant length (71.38cm), number of seed per head (32.37), weight of one thousand seeds (22.38g) and oil percentage (22.54%) was obtained under non-stressed condition. Application 1000 ppm thiourea s increased 17.91% number of seed per head, 12% weight of one thousand seeds and 14.03% oil percentage as compared to non-application of thiourea. Also, 1mM salicylic acid showed a 6.05% oil percentage increase as compared to non-application of salicylic acid. The highest of leaf area (2599mm2) and biological yield (8656kg/ha) were observed at 1000ppm thiourea and 1mM salicylic acid under non-stressed condition. In non-stressed and 140mm evaporation condition, there was no significant difference in seed yield among application of thiourea and non-application of thiourea. In 110mm evaporation condition, application of thiourea increased seed yield. In non-stressed and 140mm evaporation condition, 1000ppm thiourea increased chlorophyll a compared to non-application of thiourea. In 140mm evaporation condition, application of thiourea decreased total carbohydrate compared to non-application of thiourea.

To evaluate drought tolerance of three cultivares of forage millet and one variety of sorghum, this experiment was conducted as split split plot based on a randomized complete block design with three replications. Irrigation frequencies consisted of irrigation after 80 (control), 120 and 160 mm evaporation from class A pan as main plots and sub-plots was consisted of sorghum cultivar (Sorghum bicolor cv. Speedfeed) and three cultivares of millet (Setaria italica cv. Bastan, Panicum miliaceum cv. Pishahang and Pennisetum americanum cv. Nutrifeed). Flage leaf sampling was done at three stages, before, one and three days after irrigation. According to the results, delaying in irrigation caused a reduction in leaf pigments and yield of forage, and it also increased proline, sucrose and soluble sugars of leaf.  Continuation of drought stress effects was observed in the days after irrigation. According to the results for the studied cultivars, 120 and 160 mm evaporations were the moderate and sever irrigation frequencies respectively. It needed at least three days to recover the effects of moderate stress. Speedfeed sorghum produced maximum yield, in each irrigation frequencies. The highest forage dry yield (9376 Kg/ha) belonged to speedfeed sorghum under normal irrigation for. There were positive correlations between yield and proline and sucrose as osmotic regulators, but leaf pigments had no significant correlation. Speedfeed sorghum had also high ability to adapt, and it repaired damages faster than millet cultivares after irrigation.

To study the effects of different intercropping ratios of black cumin and fenugreek on yield, yield components and oil percentage under weedy and weed-free conditions, a factorial experiment was conducted in a randomized complete block design with three replications at Vali-e-Asr Rafsanjan University in 2015. The treatments included five intercropping ratios (black cumin sole cropping, fenugreek sole cropping, 25% black cumin + 75% fenugreek, 50% black cumin + 50% fenugreek and 75% black cumin + 25% fenugreek) and weed management (with and without weed control). Results showed that yield of both plants were greater in sole cropping treatments, whereas the highest plant height, 1000- seed weight and seed oil were obtained from intercroppings. Intercropping systems had a relative advantage than sole cropping and total relative yield (TRY) was more than 1 in all intercropping ratios. The highest TRY was achieved in 25% black cumin +75% fenugreek (1.55) treatment under weed control conditions. Intercropping caused better weeds control, so that the number and dry weight of weeds was reduced in intercropping treatments. The yield loss due to weeds was 87.2% in sole crop and in 25% black cumin +75% fenugreek, 75% black cumin +25% fenugreek and 50% black cumin +50% fenugreek treatments were 34.8%, 27.1% and 25%, respectively. Overall, the result of this research revealed that while 25% black cumin +75% fenugreek intercropping increased TRY, it also improved weeds control.

Salinity is one of the major abiotic stresses limiting crop ‎productivities in arid regions of the world like Iran. In order to meet the food demand for ‎growing population, utilization of marginal fields which are typically areas of lower ‎productivity and show some extents of nutrition imbalance and salinity to grow alternate ‎crops like promising oil crops without substantial decrease in economic value of cash crop ‎seems a practical approach. Rocket (Eruca sativa L.) is an old native plant well adapted to ‎warm, dry climates of the Middle East region. It can play a role in crop rotation programs as ‎green manure and/or cover crop to conserve soils in fallow lands. Nonetheless, little is known ‎about its response to salt stress. This study aimed to evaluate main germination characteristics ‎and yield components of some local Eruca sativa ecotypes and identify salt-tolerant ecotypes ‎in order to use in breeding programs. ‎

This study was conducted as two separate experiments. In the ‎first experiment, germination percentage and rate and seed vigor of seven ecotypes of rocket ‎named based on the region of collection as Sirjan, Bardsir, Rigan, Shahdad, Abadeh, ‎Dehmurd and Darjaveh were assayed in a completely randomized design with two factors ‎and four replicates. Salinity (NaCl) treatments were control (distilled water), 3, 6, 9, 12, 15 ‎and 18 dS/m. In the second experiment, seeds of the same ecotypes as the first experiment ‎were sown outdoor in cement boxes filled with soil (EC=1.8 dS/m) as semi-filed condition ‎and watered normally until 4-leaf stage when treatments applied by salinized water to achieve ‎‎4, 8 or 12 dS/m. At the end of growing season, shoot biomass, grain yield, plant height and ‎number of capsules were measured. Some stress indices were calculated and results were ‎discussed by correlation and biplot analysis. ‎

Final Germination percentage and rate as well as seed vigor decreased by increasing ‎salinity in all ecotypes, although magnitude of response greatly differed among ecotypes. ‎Germination rate and seed vigor were much more affected by the adverse effects of salinity. ‎Based on scoring method, Sirjan, Bardsir and Darjaveh were identified as superior, inferior ‎and moderate ecotypes in terms of salinity tolerance, respectively. In the semi-field ‎experiment, however, responses of ecotypes to salinity were quite different to those of ‎germination as Shahdad showed the highest grain yield and shoot biomass both in the control ‎and 12 dS/m treatments. Shahdad also showed the highest values for STI, GMP, MP and HM ‎while Darjave being the lowest. Biplot analysis confirmed that Shahdad was the ecotype with ‎the highest grain yield and lowest salinity susceptibility.‎

Significant ecotypic variations were observed in terms of salinity response both ‎in germination stage and whole plant growth, though ecotypes responded differently to ‎salinity, indicating tolerance mechanisms may differ among developmental stages and not ‎closely related to geographic and climatic origin of seeds. Results suggest that rocket is semi-‎tolerant to salinity and could be a potential subsistence crop for cultivation in some saline ‎soils.‎

In order to evaluation of producibility and drought tolerance of three varieties of forage mille and one variety of sorghum, the experiment was conducted a split plot in a randomized complete block design with three replications. Irrigation frequencies consisted of irrigation after 80 (control), 120 and 160 mm evaporation from class A pan as main plots and sub plots was consisted of sorghum varietiy (Sorghum bicolor var. Speedfeed) and three varieties of millet (Setaria italica var. Bastan, Panicum miliaceum var. Pishahang and Pennisetum americanum var. Nutrifeed). Irrigation after 120 mm evaporation resulted in a mild drought stress. However, the delay in irrigation reduced values of studied growth and physiological characteristics forage yield and reserves in shoot appeared to be important in this situation. Drought stress reduced forage quality by reducing the leaf area and leafy index. Sorghum variety compared to millet varieties had higher drought tolerance due to higher dry matter production as well as the highest value of tolerance indices MP, GMP, STI and HAM. Of the three varieties of millet, Pishahang proved superiority. At control irrigation frequency, highest forage yield (6251 Kg/ha) produced by Speedfeed, and the highest forage yield (9376 Kg/ha) obtained from Pishahang among millet cultivars. Higher forage quality achieved by Nutrifeed millet due to highest of leaf dry weight, leafier index (45%) and crude protein percent (20.7), which can be considered in agronomic decisions.

In order to study the effects of cold stress on some physiological characteristics of three pre-selected of linseed, a factorial experiment based on completely randomized design with two factors and three replicates was carried out in growth chamber of Faculty of Agriculture, Vali-e-Asr University of Rafsanjan, IRAN. The First factor was cold treatment at three levels (25, 0 and -2.5 ℃) and the second factor was genotype including three accessions named MAR778b, CYP706 and IND1257 selected based on preliminary test as tolerant, semi tolerant and sensitive to cold, respectively. The results showed that temperature decrease from 25 to 0OC did not induce any significant change in any trait. On the contrary, -2.5 ℃ treatment significantly increased content of total soluble sugars, proline and malondialdehyde IND1257 (susceptible) much more, and chlorophyll content, much less than two other genotypes. Also, total leaf carotenoids content of tolerant genotype (MAR778b) at -2.5 OC was significantly lower than control (25 OC), though those of two other genotypes were not different. Finally, poly phenol oxidase activity decreased by 0 and -2.5 OC in all three genotypes but phenyl alanine amonialyase increased at -2.5 OC compared to 0 and 25 OC only in tolerant cultivar (MAR778b). Correlation analysis revealed a significant association of PAL activity with stress susceptibility index

To study the effect of bacterial siderophore on the second cropping of maize (SC645) under drought stress conditions, a factorial experiment was arranged in a randomized complete block design with three replications. Two irrigation treatments (75 (I1: unstressed control) and 120 mm evaporation from Class-A pan (I2: delayed irrigation)) and two siderophore application treatments (S1: with and S2: without application) were considered as experimental factors. The foliar application of siderophore (2000 mg l-1) were applied two times at 4-6 and 12-14 leaf growth stages. In addition, 20 Kg siderophore ha-1 was applied with irrigation at jointing stage. The results showed leaf pigments, leaf relative water content (RWC), membrane stability, leaf area index(LAI) and specific leaf area (SLA) increased at I1 compared to I2, while sucrose (saccharose), lipids peroxidation (MDA), guaiacol peroxidase and polyphenol oxidase activities decreased. S1 compared to S2, showed increased leaf pigments, the ability of osmotic adjustment, antioxidant enzymes activities, RWC, membrane stability, LAI and SLA and decreased MDA. The interaction effect showed that siderophore application increase chlorophylls (a, b and total), proline and soluble sugars of leaf in each irrigation levels. The highest forage fresh yield (8697 gm-2) belonged to I1. S1 increased forage fresh yield (1644 gm-2) compared to S2. In general, bacterial siderophore can improve the morphological, physiological and biochemical capabilities of maize and is effective in mitigating the effects of drought and in increasing photosynthetic capacity.

To study the effects of delayed irrigation on growth and ratoon of millet (Pennisetum americanum cv. Nutrifeed) in the first harvest and sorghum (Sorghum bicolor cv. Speedfeed), a field experiment was conducted as split plot based on a randomized complete blocks design with three replications in Faculty of Agriculture, Vali-e-Asr University of Rafsanjan, Iran, at summer 2014. Factors consisted of irrigation regime at three levels, including irrigation after 80 (control), 120 and 160 mm evaporation from a Class A evaporation pan as main plots, crop species at two levels, including Nutrifeed (millet) and Speedfeed (sorghum) as subplots and harvest number ( at two levels) as sub-sub plots. At regrowth, all treatments were irrigated as control regime (80 mm evaporation). At 1st harvest, delayed irrigation decreased leaf photosynthetic pigments contents, LAI, SLA, LWR, leaf and stem dry weight and forage yield and increased proline, sucrose and leaf soluble sugars contents at both species. Similar effects of delayed irrigation were observed at regrowth. The highest forage yield belonged to normal irrigation of Speedfeed (9376 kg/ha), however, Nutrifeed showed a better performance at regrowth (4250 and 3816 kg/ha of forage, respectively). Nutrifeed had a better forage quality, owing to a higher leafiness index at both harvests (46.7% and 45.0%, respectively).

Salinity stress is regarded as one of the most important abiotic factors limiting plant growth and agricultural products, particularly in arid and semi-arid regions. Sesame (Sesamum indicum L.) is an important oilseed crop rated moderately salt tolerant and capable of producing profitable crops in saline conditions. Germination and seedling establishment are critical stages in the life cycle of plants especially under stress conditions. Different methodologies have been adopted by plant physiologists in different crops to alleviate salt stress. Seed priming has proven beneficial in this regard in many important agricultural crops. Salicylic acid is one of the physiological processes regulators that it increases resistant of plants to environmental stresses such as salinity stress.
To evaluate the effect of different levels of salinity and seed pretreatment with salicylic acid (SA), on some growth indices and nutrient uptake of sesame (Sesamum indicum L.) seedling, a factorial experiment with completely randomized design and four replicates was conducted in Department of Agronomy, Rafsanjan University of Vali-e- Asr. Factors were seed pretreatment with three levels including, distilled water, 1 mM salicylic acid and 2.5 Mm salicylic acid and salinity at three levels: control (Hoagland standard solution, 2.5 dS.m-1), 6 and 9 dS.m-1. A dry seed treatment (no pretreatment) was also added and considered as control.
Results showed that at 9 dS/m-1both SA concentrations caused significant increase in emergence percentage compared to dry seed and distilled water. Plant leaf area and SPAD values decreased along with salinity in dry seed and distilled water, nevertheless, at 2.5 mM SA, values were not significantly different between 6 and 9 dS.m-1. On the other hand, SA seed pretreatment decreased shoot Na and increased K content, although shoot Mg and P contents were the highest at 1 and 2.5 mM SA, respectively. The effects of SA pretreatment on shoot dry mass was not clear. The highest shoot, root and seedling dry weights were observed at control salinity in dry seed, distilled water and 2.5 mM SA and decreased with salinity level. Seedling dry weight was not significantly lower than control only in 1 mM SA and 9 dS.m-1 salinity.
Generally, in this experiment ameliorative effects of SA pretreatment were more pronounced on seedling survival and some nutrient uptake.

To study the effect of bacterial siderophore on the second crop of maize (SC645) under drought stress conditions, a split-factorial experiment, arranged in a randomized complete block design with three replications was conducted in Faculty of Agriculture, Vali-e-Asr University of Rafsanjan at summer 2014. Sampling time was considered as main factor. Five samplings were performed after imposing the irrigation treatments. The factorial combination of two irrigation intervals (75 (unstressed control) and 120 mm evaporation from Class-A pan) and two siderophore application treatments (with and without application) were considered as sub factors. The foliar application of siderophore (2000 mg l-1) was applied two times. In addition, 20 kg siderophore ha-1 was applied with irrigation. The chl a, b and carotenoids decreased with delay in irrigation while increased with siderophore application in each irrigation. Also, proline, soluble sugars and sucrose accumulated with increasing irrigation intervals and delay in irrigation. Increase in intervals and delay in irrigation without siderophore application resulted in an increase in membrane lipid peroxidation. The trend of changes in traits was significantly influenced by the availability of soil moisture, and modifications in the above-mentioned trait values were observed with delays in irrigation. Irrigating (rewatering) of plants subjected to water deficit stress did not improve their traits values compared with the unstressed control, indicating that short-term effects of drought would not recover by irrigation. Bacterial siderophore enhances the ability of osmotic adjustment and photosynthetic capacity and is effective in ameliorating the harmful effects of drought.

In order to evaluate the effect of irrigation interval on vegetative growth and seed yield of grass pea and hairy vetch, a field study was conducted as split plot with randomized complete blocks design and four replication in research farm of Vali –e– Asr University of Rafsanjan. Main plots were irrigation levels including 40, 60, 80 and 100 mm evaporation from evaporation pan class A and sub plot were crop species in two levels as grass pea and hairy vetch. Result showed that 66 days after sowing (two weeks before flowering) leaf relative water content (RWC) of grass pea and hairy vetch significantly reduced by increased irrigation regime from 40 mm, however there were no significant differences between 60, 80 and 100 mm. Also, plant leaf area and biomass of both crops were reduced by increased irrigation regime. While grass pea had higher leaf area than hairy vetch, both crops had similar biomass. Finally, yield and yield components of both crops decreased by irrigation interval, although grass pea had always higher yield components and seemed to be more drought tolerant. Results suggested that both crops well tolerated increased irrigation interval and were suitable for forage production if harvested at flowering, however, grass pea was better for grain production.

In order to selecting of salinity tolerant variety (ies) of Canola in saline conditions and determination of the salinity response, 60 canola varieties were evaluated during two years. In the first year we reduced the number of varieties in the way of logic reduction by Augment experiment. Total of 41genotypes were eliminated and 19 of them were evaluated in the second year. So, the salinity response of selected varieties was investigated in this paper. The experiment was conducted as a split plot design with randomized complete block design in three replications. The salinity of irrigated waters (2 and 11 dS/m) were as main plot and varieties were placed in subplots. Based on the results of the experiment, the average of grain yield was 2419.8 and 1456.5 kg.ha-1 in high and low salinity conditions respectively, so that there was significant differences between them at 1% level of probability. In the low saline condition, the varieties of Hyola401, Opera, Option500, Sarigol, Hyola420, SYN and Option501 were produced higher grain yield rather than others. Also in the high saline condition, the varieties of Hyola420, Hyola401, Option501, RGS, Mozart, SYN, and Rindow had higher grain yield rather than others. Evaluated of the grain yield in both low and high saline condition showed that the varieties of Hyola420, Hyola401, Option501, Opera, RGS, Option500, Mozart, SYN, and Sarigol were produced highest average yields of 2871.4, 2814.4, 2400.7, 2394.7, 2347.4, 2338.5, 2295.4, 2288.5 and 2178.8 kg.ha-1, respectively.

In order to investigate the effect of priming techniques on germination parameters of black cumin (Nigella sativa L.), sixteen seed priming treatments, including control (no priming), three hydropriming levels with distilled water (24, 36, and 48h), three osmopriming levels with PEG (solutions with osmotic potential of -4, -8 and -12 bar), three hormonepriming levels with GA3 (50, 100 and 150 ppm) and three halopriming levels with KNO3 solution (2, 3, and 4%) and three zinc sulfate levels (0.1, 0.3 and 0.5%), was conducted through a completely randomized design with four replications. The results showed that the maximom germination rate was observed with KNO3 2% and ZnSO4 0.5%, respectively. Seed priming treatment nether improve germination percentage, radicle and shoot dry weight and radicle and shoot length than control, nor decrease significantly some of them. Polyethylene glycol, GA3 and hydropriming didn’t affect the germination improvement of black cumin, however KNO3 2% and ZnSO4 0.5% treatments were effective on germination rate and seed vigor. In conclusion, seeds treatment with ZnSO4 0.5% and/or KNO3 2% could be recommended to improve the black seed germination in field conditions.

This study was conducted to evaluate the yield and yield components of promising lines of barley under saline irrigation water (ECw=10 dS/m) at experimental farm of Agriculture and Natural Resources Research Center of Yazd, located in Ardakan during the 2012-2013 growing season. 18 promising lines and two control lines (EMBS-89-18 and Line-4-salt) were studied in a randomized complete block design with three replications. Seedling emergence percent, plant height, number of infertile and fertile tillers, spike length, number of seed per spike, spike yield, seed weight, hectoliter weight, protein, phosphorus and ash content of grain were measured. Salinity has no significant effect on field emergence percentage. There were significant differences in most studied traits among the lines. However, lines were divided into four groups, based on the yield and yield components. A group that consisted 6 lines along with control line EMBS-89-18, produced more yield than other lines. Thus, these lines could be considered for more investigations for cultivation in saline areas. Based on the agronomic characteristics, it can be said that barley genotypes with restricted and faster tillering, higher reproductive components per spike, seed weight and biomass were more tolerant to salinity which could produce acceptable grain yield under these conditions. The stepwise regression analysis showed that 1000-seed weight justified 52% of the variation in grain yield per plant, therefore, it could be concluded that 1000- seed weight was the most important yield component under saline condition.

at the research farm of Vali-e-Asr University of Rafsanjan in 2013. The experiment was arranged in a randomized complete block design with four replications and four irrigation intervals. Irrigation was done after 40 (control), 60, 80 and 100 mm evaporation from pan class A, from seedling establishment till physiological maturity. Results showed that irrigation level did not significantly change percentage of qualitative traits including Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Acid Detergent Lignin (ADL), starch and crude protein as well as 1000- seed weight. However, above mentioned qualitative traits content as well as seed number per plant, seed and biological yield were significantly affected by irrigation interval. Based on mean comparison results, only 100 mm evaporation treatment significantly reduced qualitative traits content and there were no significant differences between 40 to 80 mm evaporation. Also, seed yield, seed number per plant and shoot biomass were the highest in 40 mm (165.5 g/m2, 36.17 per plant and 2.4 g/plant, respectively) and the lowest in 100 mm irrigation treatment (63.1 g/m2, 24.5 per plant and 1.07 g/plant, respectively). Based on the results, it seems that grass pea qualitative forage yield is relatively tolerant to water deficit till 80 mm evaporation.

The main objective of this study was to describe emergence rate response to temperature and estimate cardinal temperatures (base, optimum and ceiling temperatures) and biological days requirement for safflower emergence. To do this, four safflower cultivars (Esfahan, Goldasht, Padideh and Sofeh) were sown at 12 sowing dates (every month) and the emergence rate (inverse of time to 50% emerged seeds) was calculated for each sowing date. The segmented, dent-like and beta functions were used to describe the relationship between emergence rate and temperature. Root mean square of deviation (RMSD), coefficient of variation (CV), correlation coefficient (r) and linear regression coefficients (a, b) between predicted and observed days to emergence were used to select the superior function. Results indicated that the compared to the dent-like and beta functions, the segmented function described well the response of safflower emergence to temperature due to the higher r (0.90-0.97), and lower RMSD (2.17- 4.06) and CV (12.3-22.4). Fit of the segmented function on data of emergence rate to temperature showed cardinal temperatures (base, optimum and ceiling temperatures) among cultivars ranged from 2.30-3.44, 20.56-23.28 and 35oC, respectively. There was no significant difference among the cultivars in terms of cardinal temperatures. The biological days requirement for emergence among cultivars ranged from 8.05 to 9.78 which were not different significantly. The quantitative information provided by this study can be used in the crop models to predict the emergence time courses under diverse temperature conditions.

To study the effect of salt stress on morphological and physiological traits of different Brassica species a greenhouse experiment was conducted in Tarbiat Modares University. Eighteen rapeseed cultivars (fifteen cultivars of B. napus and three cultivars of B. rapa)، and two levels of soil salinity (2 and 12 dS. m-1) were experimented as factorial arrangement in randomized complete block design with three replications. The total experiment duration was 50 days (time from planting to the end of rosette stage). Results showed that salt stress reduced number of leaf، leaf area، weight of petiole، blade and biomass. However salt increased the water content and relative water content of leaf، but the ratios of blade to petiole weight and phloem to xylem weight. The lowest variation was observed in the relative water content of leaf، whereas the highest variation was in biomass and leaf water content. There was no significant correlation between biomass and number of leaf. Biomass was significantly correlated with the blade area and weight. Salinity decreased the total and chlorophylla and chlorophyllb contents، potassium (K+)، ratio of potassium to sodium (K: Na+) in blade and membrane integrity. Salinity increased the concentration of Na+ in blade. Increase in the concentration of Na+ was higher than decrease in the concentration of K+ in blade. Salt stress had no effect on a/b chlorophyll and other plant pigments such as carotenoid، antocyanine and flavonoids. The concentration of proline increased in B. napus and decreased in B. rapa with increasing salinity. No significant correlation was found between proline and biomass in both species. Results of this study demonstrated that B. napus coped better with salt stress than B. rapa in early stages of growth which can be attributed to the amphidiploidy of B. napus.

A two years (2006–2007 and 2007-2008) experiment was conducted at National Salinity Research Center, Yazd, to evaluate salt-tolerant genotypes of Brassica napus, B. rapa and B. juncea. To screen genotypes in the first growing season, 58 genotypes were grown under two irrigation water salinity levels of 2 and 12 dS m-1 in an augmented randomized complete block design with six replicated checks. Nineteen genotypes were screened based on salt tolerance indices from the first growing season. In the second growing season, these screened genotypes were arranged in a split plot experiment in three randomized complete blocks with two irrigation water salinity levels of 2 and 12 dS m-1. Stress tolerance index, arithmetic mean, geometric mean and harmonic mean correlated significantly with grain yield under stress and non-stress conditions, showing that these indices are more efficient to recognize salinity resistance. Three-dimensional and cluster plots and bi-plot analysis showed that Hyola401 and Hyola420 were the most salt-resistance genotypes following by Option501 and RGS003. In addition, CVRoby, Elite, Milena, Okapi, SLM and Zarfam had low yield performance under salt stress. In general, B. napus indicated greater resistance to salinity than other species.

The appropriate planting pattern of safflower in summer planting might be different from the planting pattern suitable for spring planting, and this has not been determined under Isfahan environmental conditions. A field experiment was conducted in the summer of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plant m-2). The experiment was planted in June 13 using local safflower variety of Isfahan, named Koseh. Leaf area index, number of heads per branch, number of seeds per head, 1000-seed weight, seed yield per plant and harvest index were not significantly effected by row distance. Increase row distance significantly enhanced most developmental stages and increased number of branches per plant and per square meter, but significantly decreased number of heads per plant and per square meter and seed and petal yields. The highest seed and petal yields (3841 and 373 kg per ha, respectively) were obtained with 30 cm row distance. Plant density had no significant effect on number of branches per plant, number of seeds per head, 1000-seed weight and seed yield per plant and per unit area. Plant density significantly enhanced most developmental stages and increased leaf area index, number of branches and number of heads per square meter, but significantly decreased number of heads per branch and per plant, petal yield and harvest index. The highest seed yield without petal clipping (4341 kg per ha) was obtained with 30 cm row distance and 50 plants m-2 treatment. The results obtained in this experiment indicate that this planting pattern might be appropriate for summer planting of safflower under conditions similar to this experiment.

Planting pattern through changing vegetative growth and utilization of environmental resourses affects yield components and seed yield. These effects were studied in the spring of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat, and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plants m-2). The experiment was planted on March 13 using local safflower variety of Isfahan, named Koseh. Increase in row distance and plant density enhanced most developmental stages of safflower. Leaf area index was not significantly affected by row distance but increased as planting density increased. Up to the 50% flowering stage, 30 cm row distance produced highest plant dry weight, but had the least dry weight at the end of the growing season, probably due to the strong shedding of leaves. Up to the end of flowering stage, 50 plants m-2 treatment produced the highest plant dry weight, but ranked lower as compared to 30 plants m-2 treatment at the physiological maturity, probably due to the shedding of leaves. Row distance had no significant effect on number of branches per plant and per square meter, number of heads per branch, number of seeds per head, 1000-seed weight and harvest index. But number of heads per plant and per square meter as well as seed yield per plant and per square meter significantly decreased as planting distance increased. Plant density had no significant effect on number of branches per plant, number of heads per square meter, number of seeds per head, 1000-seed weight and seed yield. Increase in planting density increased number of branches per square meter, but reduced number of heads per branch and per plant, seed yield per plant and harvest index. The highest seed yield (4769 kg ha-1) was obtained with 30 cm row distance and 40 plants m-2 treatment. On average, 397 kg ha-1 petal was harvested, which has a large economic value. However, petal clipping, over all treatments, reduced seed yield by about 7.4%. Considering the advantages of uniform distribution of plants and adaptation of safflower to flat planting, 30 cm row distance with 40 plants m-2 might be appropriate for planting safflower under conditions similar to this experiment.