JOURNAL OF CROP ECOPHYSIOLOGY
Year:2011 | Volume:2 | Issue:4|Papers Count:11

In order to study of drought tolerance in 4 sunflower hybrids according to ecophysiologic characteristics, three separate experiments were conducted as randomized complete block design at the research field of Seed and Plant Improvement Institute-Karaj in 2006. The first experiment conducted at optimum conditions and plants were irrigated after 60 mm evaporation from evaporation pan, class A, whereas the second and third experiments were irrigated after 120 and 180 mm evaporation from evaporation pan. These were considered as mild and sever drought stress conditions, respectively. Combined analysis of variance results indicated that drought stress had significant effect on ecophysiologic and agronomic characteristics and leaf area index (LAI), specific leaf area (SLA), solar radiation interception and remobilization showed significant difference among hybrids. Also, interaction effect between stress and hybrids was significant on specific leaf area (SLA), leaf area index (LAI), remobilization and stomata conductivity. Drought stress caused a decrease in specific leaf area (SLA), leaf area index (LAI), solar radiation interception, stomata conductivity, yield and its components, whereas remobilization increased under drought stress. Under sever drought stress, Allstar hybrid had the highest specific leaf area (125 cm2.g-1), leaf area index in flowering stage (1.8) and stomata conductivity (1.41 mol.m2.s-1) and appropriate remobilization (47 g). Also, in three treatments irrigation, Allstar hybrid exhibited the highest seed yield as 3227, 1671 and 702 kg.ha-1 respectively.

In order to determine the effect of nitrogen levels and time of nitrogen fertilizer application on quantity and quality characteristics of mustard in summer planting, a factorial experiment base on randomized complete plot with three replications, in farming year of 2007 has taken place in research station of Varamin, in city of Varamin. In this study, three nitrogen levels (75, 150 and 225 Kg/ha), four splitting patterns (P1: 1/3 at planting time, 1/3 at shooting, 1/3 at bud initiation. p2: 1/3 at four to six leaves, 1/3 at shooting, 1/3 at bud initiation. P3: 1/2 at four to six leaves, 1/2 bud initiation. P4: 1/2 at four to six leaves, 1/2 at shooting) was studied. According to the results maximum seed yield approached in 75 kg/ha nitrogen application and pattern 4 for time nitrogen fertilizer. 75 kg/ha nitrogen application shown best seed oil percentage. Time of nitrogen fertilizer applications were effective significantly (1%) on seed yield, seed oil percentage. Nitrogen levels and time of nitrogen fertilizer application interactions were significantly effective (1%) on Biological yield, seed oil percentage, seed protein percentage but not effective on seed yield.

In order to studying the effect of some effective traits such as leaf area duration on grain filling in 3 cultivars of corn an experiment took place in split plot as completely randomized blocks design , with three replications was conducted during 2008- 2009 at Agricultural Research Station, Islamic Azad University, Tabriz branch, Iran. Experimental factors were cultivars of corn in three levels: early maturing (307), average maturing (Jeta), and late maturing (704) in the main plots and foliar application included in seven levels: control (lack of foliar application use), teaseling appearance, earning appearance, beginning of grain filling, grain pasting, concurrent foliar application in teaseling appearance and beginning of grain filling stages and concurrent in teaseling appearance, earning appearance, beginning of grain filling and grain pasting in the sub plots. The results showed that foliar application of urea had a significant effect on total grain weight increase and this increase with foliar application of urea took place in concurrent foliar application of urea in teaseling appearance, earning appearance, beginning of grain filling and grain pasting stage. Foliar application in whole stages after teaseling increased seed yield of Jeta cv (23.5%) compare with control. Foliar application had a significant effect on chlorophyll content index and leaf area index and duration. According to the findings of this survey, it is possible to use foliar application of urea for increasing total grain weight per plant by increasing of canopy chlorophyll and leaf duration.

In order to effect sprayed titanium dioxide nanoparticles on some agronomic characteristics in wheat under drought stress testing as a split split plot randomized complete block design in four replications in 1388 in agricultural research farm, Islamic Azad University, Shahr-e-Qods was implemented. The results showed that nano-particles sprayed at 1% significant difference in height, spike weight, grain yield and harvest index in normal and drought conditions there. The results showed that these traits affect drought stress and drought stress was imposed time and amount of these attributes was reduced. The results also showed that grain yield in drought conditions with sprayed titanium dioxide nanoparticles 02/0 per cent, compared to 23% sprayed non-drought conditions increased.

To identify the status of white bean samples, selected by the national plant gene-bank of Iran, in case of growth time and also determining the relation of plant phonological stages with the grain yield and its components; a study was conducted, on ten selected lines of white bean (Phaseolus vulgaris L.) with the most yield, on the research field of Karaj’s seed and plant improvement institute in the year 2008. The plant vegetative and reproductive stages, biological yield traits, number of seed’s per plant and the yield components were measured. The results showed that among phonological traits, the most positive and significant correlation was pertaining to the collective GDD traits up to the level of R5. Among the genotypes, no difference was seen in the stage of V4, and the genotypes’ distinction initiated from the level of R5. Partially, the genotypes with the most GDD, while entering the reproductive and maturity stages, have shown more potential in the production of more yields. As far as the genotypes (1.4) and (4.1) have reached the most GDD among all phonological stages, and the genotype (4.1) due to the better condition in case of yield components and biological yield has finally shown more grain yield.

In order to study the Effects of different levels of nitrogen and plant density on oil yield and its components of Castor, this experiment was conducted at Agronomy Jihad field of Qazvin in 2006. Field experiment was carried out by a split plot design with 4 replications. The factors which studied were nitrogen levels 0, 40, 80 and 120 kg ha-1 and plant density with 2.5, 4 and 5.5 plant m-2. The results showed that nitrogen significant effect on seed yield, oil yield and lateral stem (a=1%), seed thousand weight (a=5%) and oil percent was not significantly affected due to nitrogen. Comparison showed that highest seed yield and oil yield were achieved under application of 80 kg ha-1 nitrogen, highest seed thousand weight under 120 kg ha-1 nitrogen and highest lateral stem under 40 kg ha-1 nitrogen. Also plant density significant effect on seed yield, oil yield and lateral stem (a=1%), seed thousand weight (a=5%) and oil percent was not significantly affected due to plant density. Comparison showed that highest seed yield and oil yield were achieved under 5.5 plant m-2, highest seed thousand weight under 4 plant m-2 and highest lateral stem under 2.5 plant m-2. Interaction of nitrogen and plant density significant effect on oil yield and lateral stem (a=1%), seed yield (a=5%) and other characteristics were not significantly affected due interaction of nitrogen and plant density. The results of this experiment showed that were affected nitrogen and plant density on oil yield and its component sorely that is gist for received to oil yield maximum of Castor.

This study was performed to evaluate the different levels of heavy metal cadmium [0-40-80 mg /kg soil CdCl2] on Cd uptake in root and shoot of annual medic (Medicago scutellata). This experiment was done in 2009 in Research Greenhouse of Islamic Azad University-Karaj branch in completely randomized design with 4 replications. The results indicated that this was the concentration of cadmium in the soil content of chlorophyll a, b and a + b showed significant reduction (P<0.05) and the activity of antioxidant enzymes and biomarkers destructive capacity of the studied were significantly increased (P<0.05). Increased uptake of soil cadmium element in any capacity of each annual medics Nshandarknndgan biological, malondialdehyde (MDA), CD and DVD tyrosine hydroxy Gvanvzyn (8-oH-DG) showed a significant increase P<0.05)) to so that this increase due to the toxic effects of cadmium, respectively, on the lipid aldehydes, protein and cell nucleus was also decreasing trend in the content of chlorophyll a, chlorophyll b and chlorophyll Total (a + b) in the highest concentration of cadmium (80 mg kg) used in soil was observed. Tuesday enzyme activity and yield SOD (SOD), catalase (CAD) and glutathione peroxidase (GPX) in response to the toxicity of cadmium in shoot species studied showed a significant increase (P<0.05). With regard to the effects interaction factors were tested treatments] b5 (polymer application Svprjazb+bacteria growth stimulating) and b9 (application+Hvmyk acid bacteria growth stimulating) [the highest level of cadmium toxicity (80 mg kg soil) had the lowest enzyme SOD, CAT and were GPX.

In order to determine the optimum sowing date of different medicinal flax genotypes, a split plot experiment with completely randomized block design with 12 treatments and 4 replications were conducted at experimental farm of Yasooj Islamic Azad University. The treatments were composed of four different combinations of sowing dates ((Feb. 20, Mar. 6, Mar. 21, and Apr. 4) and 3 flax cultivars (Somaco, India, and Foster). The studied traits were as follows: plant height, 1000-kernel weight, harvest index, grain yield, Biological yield, Leaf Area Index, Crop Growth Rate and Relative Growth Rate. The results showed that there is a significant effect of between various sowing dates regarding the plant height, biological yield, Relative Growth Rate, Net Photosynthesis Rate, Leaf Area Index, grain yield, and 1000-kernel weight and for harvest index. Besides, the analysis of the data variance shows that there is a significant effect of between investigated genotypes regarding the plant height, biological yield, Crop Growth Rate, Relative Growth Rate, Leaf Area Index, grain yield. According to the results of experiment, the first sowing date (Feb. 20) and Somaco cultivar are recommended as the suitable for higher grain yield.

In order to study the Effect of plant density and nitrogen on essential oil percent of Calendula (Calendula officinalis L.), a experiment was conducted at Research Field of Center Education Agriculture of Gazvin in 2005. Field experiment was carried out as Factoriel design with 3 replications. plant density  with three levels density 20,30 and 40 (Pl.m-1) and Nitrogen level was 30, 60, 90 and 120 kg ha-1. The results showed that plant density had significant effect on lateral stem, weight dry petal and essential oil yield. Means comparison showed that plant density with 30 (Pl.m-1) had the highest essential oil yield with 1.10 kg ha-1. moreover nitrogen significant effect on lateral stem, weight dry flower , weight dry petal, number flower(Pl.m-1), essential oil percent and essential oil yield. Means comparison showed that highest essential oil yield with 1.24 kg ha-1 was achieved under application of 60 kg ha-1 nitrogen .Our results showed that plant density with 30 (Pl.m-1) and 60 or 30 kg ha-1 nitrogen increased essential oil yield of calendula in this condition.

In order to evaluate the effect of different times hydropriming on the quality seedling production during germination in sunflower, this experiment was carried out in 2010 at Laboratory Sciences, Islamic Azad University Shahr-e Qods Branch by a completely randomized design with four replications and the first of experiment, seed viability was determined by Tetrazolium test method. The factors studied included different times of hydropriming (4, 8 and 12 hours) through the placing seeds were exposed to distilled water and sunflower cultivars (Golshid, Goldis and Azargol cul.). The results showed that the hydropriming and cultivars had significant effects on seedling vigour, germination percentage and seedling dry weight in P£0.01 and coefficient of velocity of germination, mean daily germination, germination rate and mean time to germination wasn’t significantly affected due to by hydropriming and cultivars treatments.