جستجوی مقالات مرتبط با کلیدواژه « آفتابگردان » در نشریات گروه « باغبانی »

In order to study the effect of priming sunflower seeds by potassium nitrate on germination seeds was conducted experiments in salinity and drought conditions. Location of experiments was Physiology Laboratory, Faculty of Agriculture, Bu Ali Sina University, Hamedan. Salinity experiment was conducted as factorial based on randomized complete block design (RCBD) with two factor of seed priming and salinity and three replications. Priming levels included control and seed treatment by potassium nitrate and salinity levels included 0, -2, -4, -6, and -8 bar. Also, drought experiment was conducted as factorial based on randomized complete block design (RCBD) with two factor of seed priming and drought levels in three replications. Drought experiment treatment included control (non-priming) and priming by potassium nitrate and drought stress treatment were five levels (0, -2, -4, -6, and -8 bar). The results of two experiments showed that increasing in salinity and drought stress, decreased germination components including germination, germination rate and dry weight of seedlings. However, this reduction was lower for seeds that were treated by potassium nitrate. In terms of the studied traits, at all of the levels of salinity and drought treatment seeds were better than control seeds. In general, it can be concluded that the priming of sunflower seeds by potassium nitrate improved the germination components under salinity and drought stress and can increase sunflower plant resistant against these stresses in the germination stage.

The purpose of this study is surveying the genetic diversity between oilseed sunflower genotypes and relationships between traits and grain yield, so 12 genotypes cultivated in a completely randomized block design with three replications. Based on the results of analysis of variance, traits were observed among genotypes at a probability level of 1% for the traits of 100 seeds and at 5% probability for the traits of diameter and grain yield of diversity. The results of simple correlation coefficients of traits showed that the diameter of the plant had the highest correlation with plant height and 100 seed weight. The results of simple correlation coefficients of traits showed that the diameter of the plant had the highest correlation with plant height and 100 seed weight. The results of path analysis showed that the highest direct effect on seed yield was observed on seed width and plant height. Using factor analysis by principal component analysis, four factors justify 82.5% of the data variation. The first factor justified 34.2% of the total variance of the data, that named seed yield, the second factor justifying 21.9% of the variation factor that named length factor ,the third factor, justifying 14.5% of the data changes as the factor of 100-grain weight and the fourth factor justified 11.7% of the total data variance, was named dimeter factor.

This study carried out to examine the relationships between effective traits and yield in 12 sunflower varieties. A randomized complete block design with three replications was used. Results of simple correlation showed that seed width, seed diameter, seed length and hundred grain weight correlations with kernel yield were significant at the 1 percent probability level. In stepwise regression analysis, seed width was the first trait entered in the model and explained approximately 67 percent of the total yield changes. Seed length and diameter of stem entered to the model after the seed width trait and a total of 88 percent total yield variation was explained. The characters entered into the regression model were used for path analysis to identify direct and indirect effects of traits on grain yield and their proportion of effect. The results showed that seed width, seed length and stem diameter had the most direct and positive effect on the yield, respectively. In this study, three independent factors encompassed 75 percent of the total variation. The first factor with 35.5 percent of the variance was mostly influenced by grain yield, plant height, leaf length and leaf width which was named the grain yield. The second factor with 26 percent of the total variation was mostly represented seed length and seed weight and named seed features. The third factor was highly affected by stem diameter, seed diameter and seed width with 13.4 percent of variance explained and was named the plant diameter.

To study the effects of spray Methanol on farming and morphological characteristics under water deficit stress on oil sun flower was conducted on RCBD with three replications at research station of Islamic Azad University Varamin branch, in 2012. Experimental factors were water deficit stress as main plots (normal irrigation, drought stress in flowering phase and drought stress in filling of grain phase) and methanol ( lack of methanol, 10% methanol, 20% methanol and 30% methanol) as sub plots. Times of spray methanol were when plant had 8 leafs, 15 days after and 15 days after. Results showed that drought stress decreased1000 kernel weight, Head diameter, grain yield, biological yield but it increased EC. Also spray methanol increased grain yield, biological yield, 1000 kernel weight, Head diameter but it decreased EC. Analysis of variance showed that interaction drought stress and spray methanol significantly affected on investigated traits.Maximum grain yield was obtained from normal irrigation and spray methanol that was 3205/667 and minimum grain yield was obtained from drought stress in filling of grain phase and lack of methanol that was 1648/371.In general, sun flower is sensitive in filling of grain phase and methanol decrease drought stress effects.

To evaluate the effect of salinity on phytoremediation of contaminated soil by plant sunflower, an experiment in the greenhouse, College of Agriculture, Islamic Azad University of Varamin in 2013. Factorial experiment was conducted in a completely randomized design experiment consisted of first factor is soil contamination with cadmium at four levels: 0, 30, 60 and 90 mg of cadmium per kg of soil salinity and the second factor of four levels of NaCl: 0, 2, 4 and 6 dS m. The highest cadmium leaves and stems of treatment (90 mg of cadmium per kg of soil and 6 dS m) with an average of 6.33 mg per kg of dry matter and the lowest related to treatment (90 mg of cadmium per kg of soil and control) with 13.13 mg per kg and the highest cadmium absorption coefficient in saline (6 dS m 30 mg of cadmium per kg soil) with 0.199 and with the treatment (control 90 mg of cadmium per kg of soil 0.095), the highest and lowest percentage of protein and 90 milligrams of cadmium per kilogram of soil control respectively 32 and 23 percent, respectively. The highest percentage of protein in the treatment 6 (dS m) with an average of 38 percent was achieved. The protein content of the control (salinity), respectively. The highest amount of chlorophyll a to control the salinity of 6 dS m with an average of 1.096 and 0.767 mg per gram of fresh weight, respectively. The highest and lowest proline content in 90 mg of cadmium per kg of soil and control with an average of 621 and 523 micromoles per fresh weight, respectively .Hieghest and lowest relative water content in irrigation and 90 mg of cadmium per kg soil respectively by 76 and 60 percent, respectively. Most RWC control (salinity) with an average of 74 percent was achieved. Lowest levels in treatments 6 (dS m). The result showed that salinity and cadmium on relative water content, proline content, the content of cadmium in leaves and stems, the absorption coefficient of Cd, protein, chlorophyll a significant effect, but the effect EC on oil percent was not significant. Interaction between cadmium and salinity on cadmium content in leaves and stems, cadmium absorption coefficient, chlorophyll A was significant. Salinity increased plant availability and cadmium so that the cadmium content in wheat increased significantly with increasing salinity.

This study aimed to investigate the effect of drought stress and foliar application of silver nanoparticles on morphological and physiological characteristics of sunflower (Helianthus annuus. L) and split-plot in a randomized complete block design with three levels of water stress agent the main factor (I0: 60 mm evaporation from pan class a (normal irrigation), I1: 90 mm evaporation from pan class a and I2: 120 mm evaporation from pan class a) and foliar application of silver nanoparticles four levels as subplots (NS0: sprayed with water, NS1: 50 mg nano-silver, NS2: 90 ppm silver nano, NS3: 130 mg nano-silver) and three replications. respectively. The results showed that the effects of irrigation and silver nanoparticles and their interactions at the level of one and five percent of the studied traits had significant impact. The highest yield (4038.49 kg.ha), oil yield (2134.52 kg.ha) with normal irrigation treatment, 60 mm × 130 milligrams per liter of nano-silver evaporation and biological yield (11248.8 kg.ha) with normal irrigation treatment, 60 mm × 90 mm evaporation of silver nano-grams per liter respectively. The highest chlorophyll a and normal irrigation treatment of 50 mg per liter of nanosilver with (25.05 mg) was given. Stress increases the levels of malondialdehyde (MDA). The highest MDA (MDA) with (12.71 nmol g) fresh from severe stress and weight was sprayed with purified water. The lowest yield (3091.6 kg.ha) and biological yield (8787.2kg.ha) and oil yield (1326.99kg.ha) related to severe stress, 120mm × water evaporation was observed. The lowest level of MDA of normal irrigation, 60mm evaporation with (6.19nmolg.fw) and chlorophyll a to severe stress, 120mm evaporation (17.72 mg of fresh leaf weight) less the amount of support.

In order to evaluate the effect of irrigation and pattern of nitrogen topdressing on yield and yield components of sunflower, an experiment was carried out in complete block design with split-plot arrangement in three replications during 2012 growing season. Irrigation regimes were allotted to main plots and nitrogen treatments were allotted to sub-plots. Irrigation regimes were consisted of: 1) moderate irrigation 2) water stress at V8 growth stage and 3) water stress at heading stage. The nitrogen treatments were consisted of: N1: 25% at sowing, 50% at V8, 25% at heading; N2: 50% at V8, 50% at heading; N3:50% sowing, 50% heading; the results showed that water stress at heading significantly decreased the head diameter and100-grains weight and non-significantly decreased the grains per head which was resulted to 15% lower grain yield comparing to the moderate irrigation. Under moderate irrigation, N3 treatment non-significantly increased the head diameter and biomass comparing to the N2 treatment by 9 and 16% respectively. Under water stress at V8, N3 treatment significantly increased the head diameter and biomass comparing to the N1 treatment by 12 and 29%, respectively. This result showed that choosing a suitable pattern of nitrogen top-dressing for attaining the maximum grain yield is more important when the plants are not suffering water stress or stress is occurred at early vegetative stage. But when the stress is occurred at early vegetative stage, then the pattern of nitrogen topdressing is not such important.

To evaluate the effect of superabsorbent and without application of quantitative and qualitative characteristics of sunflower oil and water deficit stress conditions, the pilot in 1391, Azad University of Varamin Agricultural Research Station (Pishva) was carried out. This study was a split plot in a randomized complete block design with three replications. Where irrigation as main factors (lack of tension, the tension in the fourth and fifth pair of leaves, water stress at flowering, drought in the fourth and fifth pairs of leaves and flowering) and the concentration of the polymer, super absorbent (zero, 15 and 30 kg per ha) as sub plots were purpose. Traits such as seed yield, oil content, protein content, chlorophyll and relative water content were studied. The results showed that water deficit, particularly at the flowering stage reduced the grain yield, leaf chlorophyll content, leaf relative water content, oil content and the increased use of super absorbent of all the characters. Stress protein was also increased. The results obtained in this experiment can be concluded that the most critical stage in the flowering stage and twostage stress (vegetative and reproductive) is very sensitive to drought stress and Application of 30 kg ha super absorbent to lessen the impact of drought was identified as the best treatments.

Drought is one the most important factors limiting yield and culture area of crop plants which also may modify the yield quality. Identification of genetic factors improving plant drought tolerance might increase the efficiency of breeding programs aimed to attain drought tolerant cultivars. In order to find genomic regions affecting drought tolerance، as well as markers linked to drought tolerance، 100 recombinant inbred lines including their two parents، RHA266 and PAC2، were cultured in field under full and limited irrigation as an alpha-lattice arrangement with two replications. Analysis of variance revealed significant differences among the genotypes in both conditions. QTL mapping using composite interval method resulted in identification of several genomic regions controlling the drought tolerance traits. Some yield QTLs were common in both normal and drought conditions، and some were specific to drought condition. Results suggested that selecting for lines with heavier seeds would result in superior genotypes for drought condition. Markers linked to the studied traits were identified.

In order to evaluate the effect of irrigation and pattern of nitrogen topdressing on yield and yield components of sunflower, an experiment was carried out in complete block design with split-plot arrangement in three replications during 2012 growing season. Irrigation regimes were allotted to main plots and nitrogen treatments were allotted to sub-plots. Irrigation regimes were consisted of: 1) moderate irrigation 2) water stress at V8 growth stage and 3) water stress at heading stage. The nitrogen treatments were consisted of: N1: 25% at sowing, 50% at V8, 25% at heading; N2: 50% at V8, 50% at heading; N3:50% sowing, 50% heading; the results showed that water stress at heading significantly decreased the head diameter and100-grains weight and non-significantly decreased the grains per head which was resulted to 15% lower grain yield comparing to the moderate irrigation. Under moderate irrigation, N3 treatment non-significantly increased the head diameter and biomass comparing to the N2 treatment by 9 and 16% respectively. Under water stress at V8, N3 treatment significantly increased the head diameter and biomass comparing to the N1 treatment by 12 and 29%, respectively. This result showed that choosing a suitable pattern of nitrogen top-dressing for attaining the maximum grain yield is more important when the plants are not suffering water stress or stress is occurred at early vegetative stage. But when the stress is occurred at early vegetative stage, then the pattern of nitrogen topdressing is not such important.

In order to study the effects of water deficit stress and foliar application of ascorbic acid, an experiment was conducted in research field of Islamic Azad University, Varamin Branch in Iran during 2012 growing season. The experimental design was laid out in a randomized complete block design with a split plots arrangement in three replications. Main plots included four different levels of irrigation (complete irrigation, irrigation withholding at 8-leaf stage, irrigation withholding at grain filling stage and irrigation withholding at both 8-leaf and grain filling stages) and three different concentration of Ascorbic Acid foliar application (0, 100 and 200 ppm) was allocated to subplots. The results showed that irrigation withholding conditions in different growth stages significantly decreased seed yield, biological yield, harvest index, oil and protein percentage, oil and protein yield and total chlorophyll content but by contrast increased proline content and superoxide dismutase activity in leaves. Foliar application of ascorbic acid as antioxidant enzyme could increased quantitative and qualitative yield and chlorophyll content and decreased proline and superoxide dismutase activity in leaves by reduction of water deficit stress. Foliar application of Ascorbic Acid with 200 ppm under irrigation withholding at both 8-leaf and grain filling stages increased 38/46% yield seed compared with treatment that foliar application without Ascorbic Acid. In addition, Ascorbic Acid foliar application reduced the harmful effects of water deficit stress as antioxidant and improved growth conditions for water deficit stress.

To estimate genetic parameters in sunflower single cross hybrids، a North Carolina Design I experiment was conducted in a randomized complete block design with three replications at Agricultural and Natural Resources Research Station of Khoy. In 2005، six fertility restorer male lines were crossed with 18 cytoplasmic male sterile female lines. Each male line was crossed with three different female lines to make two sets with nine hybrids in each set. In 2006، Single cross F1 hybrids were planted to estimate genetic parameters. Data were collected from agronomic traits including: flowering initiation، seed filling period، maturity، plant height، stem diameter، head diameter، 1000 seed weight، seed numbers per head، seed/achen ratio، biological yield، harvest index، oil content، seed yield and oil yield. Survey results showed that gene action in some loci for 1000 seed weight and seed numbers per head were partial dominant (a < 1)، for oil yield were complete dominant (a =1) and for other traits were over dominant (a > 1). To improve seed filling period and harvest index traits، use of selection methods is sufficient. Traits such as plant height، stem diameter and head diameter، hybridization method use to improve them is unavoidable. For important traits such as seed yield، oil yield and biological yield، using both selection and hybridization methods is recommended.

Sunflower is one of the field important crops in Western Azerbaijan and the present research was carried out in order to identify the hazardous birds and determine their damage rates on Alstar hybrid in Khoy station in 2003. Using a field binocular and a field guide book for identification of birds, two hazardous bird species, house sparrow (P.domesticus) and crow (C.corax) were identified. To estimate the damage rates of the birds, traits such as receptacle shape, bending of plant, distance between receptacle and soil surface were studied on Alstar hybrid in Khoy station. The results from the data analyses depicted the least damage rate was observed with bent plants of more receptacle angles where receptacles were concave in shape and nearer to the earth surface. The most damage rate was seen with right standing plants, easily and simply exposed to bird attacks because of the specific position of the receptacles.

In order to measure the effects of redroot pigweed emergence time and density to lightabsorption and leaf chlorophyll content at interference with three sunflower hybrids، a two years experiment was conducted during 2005-2006 based on additive design at islamic azad university of Tabriz. Treatments were combination of three different weed densities (8. 3، 25 and 41. 7 plants m-2) at three relative times of weed emergence (coincident with sunflower; and 15 and 30 days after sunflower emergence) using three different sunflower cultivars (Azarghol، Hysun and Allstar). Results revealed that in Azarghol and Hysun mixed canopy closure with increasing of density and early emergence times was happened. Because of short stem height and lower leaf area، Allstar could transmit 8% of total PAR at 60 days after sunflower emergence. In full-season interference of 41. 7 weeds m-2، light absorption by redroot pigweed in three sunflower cultivars increased 23%، 31% and 37%، respectively. With increasing of density and earlier interference times of redroot pigweed، leaf chlorophyll content index decreased in all studied treatments except in treatments of different weed densities at 30 days after sunflower emergence، and the Allstar was tolerated higher negative effect from weed density than other cultivars. With a view to grain yield in sunflower، compatibility of redroot pigweed with Allstar was higher than Azarghol and Hysun cultivars. In Allstar because of lower competitive power with weeds، redroot pigweed control is recommended at early interference times.

Effects of different planting on phonology, grain yield and its components of two sunflower cultivars were investigated. In 1996, an experiment was conducted in the experimental field of Azad Islamic University of Gonabad. The experiment was arranged in a randomized complete block design with a split plot layout and four replication. The main plot consist of four planting date (April 24 th, May 9th, May 24th and June 8 th) and sub plots were arranged for two sunflower cultivars (Record and zaria). The results of this experiment showed that there were developmental stages with delay in planting. The Record and zaria required 1755 and 1653 growing degree days (GDD) for their physiological maturity respectively. Effect of planting date on biological yield and number of seeds per head were significant and delay in planting reduced them. However, seed weight was affected by planting date and increased as planting delayed. The maximum grain yield was obtained in April 24 Cfor Record and the minimum grain yield was obtained in June 8 th for zaria. On the average, Record and zaria yielded 4773 and 4520 kg/ha, respectively. With the respect to the under condition, planting of Record cultivars in April 21th, is recommended.