Applied Agricultural Research
Year:2015 | Volume:27 | Issue:105|Papers Count:23

Growing drought tolerant crops such as pearl millet can save water where irrigation water supply is limited. The objective of this project was to evaluate the pearl millet (Pennesitum americanum) forage yield under different irrigation regimes and nitrogen fertilizer rates. The field experiment was designed as a split factorial arrangement in randomized complete block design with four replications at the Research Field of University of Tehran, Karaj, in 2007. The combination of Irrigation regimes (40, 60, 80 and 100 % maximum allowable depletion of available soil water) and nitrogen fertilizer rates (0, 75, 150 and 225 kg N ha-1) were allocated to the main plots and harvest was assigned to the sub plots. It was observed that 40 and 60% maximum allowable depletion of available soil water produced the highest dry matter yield over three harvests (21.45 and 20 t ha-1, respectively). As water depletion increased to 100% maximum allowable depletion of available soil water and getting close to the third harvest, the leaf and total dry matter yield followed a decreasing trend. At 40% maximum allowable depletion of available soil water treatment, the highest total dry matter was produced on first harvest. The interaction effect of harvest×nitrogen was highly significant on total dry matter yield. The highest yield was produced on second harvest at 225 and 150 kg N ha-1. The lowest dry matter was produced in control treatment over all harvests. Therefore, by 60% depletion of maximum allowable depletion of available soil water and consuming 150 kg N ha-1, acceptable dry matter yield could be produced.

In order to evaluation of genetic diversity of spring barley genotypes, screening drought resistance indices andidentification of drought resistance varieties, 16 variaties of spring barley were evaluated in a randomised complete block design with three replications under two conditions including normal irrigated and drought stress on flowering stage in West Azerbaijan Agricultural and Natural Research Centre. Based on the potential (Yp) and stress (Ys) yield, quantitative drought resistance criteria such as: mean productivity (MP), tolerance index (TOL), geometric mean productivity (GMP), harmonic mean (HM), stress susceptibility index (SSI) and stress tolerance index (STI) were calculated. Generally in both conditions, variety Kavir/Badia with average yield of 2152 kgha-1 and variety Union 300-4 with average yield of 498.6 kgha-1 had the maximum and minimum values of yield. In both normal and drought stress conditions, the highest value of MP, GMP and HM were possessed to genotype "Kavir/Badia". Correlation analysis between drought resistance indices with potential and stress yields revealed that indices including MP, GMP, HM and STI are most suitable criteria for screening barley’s genotypes. Varieties "Kavir/Badia" and "Rihane-O5" were chosen as best drought resistant regarding to these four criteria and high values of Yp and Ys. Multivariate biplot display that the varieties "Kavir/Badia" and "Rihane-O5", "Gorgan/CM67/Pro/Svo" and "Hebe" were located next to the vectors of drought resistance indices MP, GMP, HM and STI. Also, distribution of the varieties in the biplot space manifested the presence of genetic diversity among the varieties for drought stress. Cluster analysis indicated that the farthest genetic distance were exist between two drought resistant varieties including "Kavir/Badia" and "Rihane-O5" and two susceptible varieties including "Local- chek" and "West Azerbaijan landrace".

Investigation of salinity levels of 0 to 20 dS.m-1 of sodium chloride and Urmia Lake water on the Hyssopus officinalis showed that the minimum percent (13%), rate (1.4 per day), index (2) of germination and maximum amounts of reduction in germination (79%) were occurred at 20 dS.m-1, but the maximum one of percent (73%), rate (8.1 per day), index (23) of and minimum reduction of germination (6% increases) were occurred at 8 dS.m-1 of sodium chloride. The maximum percent (70%), rate (7.8 per day), index (23) of and minimum reduction of germination (2% increase) was obtained in 8 ds.m-1, but the minimum one of percent (54%), rate (6 per day), index (11) of and maximum reduction of germination (22% increase) Were obtained from 20 dS.m-1 of Urmia Lake water. Time to 50% germination, shoot and root length, ratio of shoot/root length, fresh and dry seedling weight were not measurable at the 20 dS.m-1 of sodium chloride. So, the longest (1.4 cm) and shortest (0.7 cm) root were respectively obtained from control (0 dS.m-1) and 16 dS.m-1 of sodium chloride. Despite of significance effect of sodium chloride on shoot/root length ratio, comparison of means showed any differences. Time to 50% germination was shortest (81 h) and longest (162 h) at 8 and 20 dS.m-1 of Lake water. The longest shoot (2.7 cm) and root (1.4 cm) was observed at 4 ds.m-1 and the shortest (0.6 and 0.3 cm) at 20 ds.m-1, respectively. The highest fresh (0.088 g) and dry (0.0077 g) weight of seedling were obtained from 16 dS.m-1 of Urmia Lake water, and the lowest fresh (0.064 g) and dry (0.0057 g) seedling weight were obtained from control.

In the second planting production areas, it can be increased farm efficiency with the second planting of common bean(Phaseolus vulgaris L.). In order to evaluate of the second planting possibility of common bean cultivars in Lordegan region, an experiment was conducted at the region in 2006-2007, using a randomized complete block design as split plot with three replications. Main plots were sowing dates (late of May, 26 June and 6 July) and subplots included cultivars (Sayyad, D81083, ARS-R93003 from red beans and Daneshkadeh, Jules and Emerson-74 from white beans). Results showed that delay in sowing date could reduce 100-seed weight, number of seeds per pod, number of pods per plant, plant height, and seed yield. Sayyad (red bean cultivar) and Daneshkadeh (white bean cultivar) had the most seed yield in each group at each sowing date, because of more pod per plant and seed per pod. In the first year, suiatable conditions were increased 100-seed weight, number of seeds per pod, number of pods per plant, plant height, and seed yield in common bean cultivars. Interaction between cultivars and sowing dates showed Daneshkadeh could be planted in the second planting only and other cultivars must be planted in the first sowing date.

Allelopathic phenomenon is an interference method of weed on crops that can help to know crop-weed interaction.This experiment was conducted to evaluation ofSinapis arvens is and Cirsium arvense allelopathic effects on canola germination and nutrient uptake in 2007 at greenhouse of University of Mohaghegh Ardabili. Treatments were differential concentrates (0, 2.5, 5, 10, 20 and 40%) of fresh and dry residual extract ofSinapis arvens is and Cirsium arvense. The experiment was laid out as factorial in completely randomized design. Analyses shown that fresh and dry extract of two weeds reduced germination of canola in compared with control 1.5 to 2.5 times. Also fresh and dry extract of weeds reduced canola dry aboveground mass. Nitrogen and P uptake reduced under fresh extract, while dry extract ofSinapis arvens is increased p uptake in canola more than 4 times. Fresh and dry extract of Sinapis arvens is andCirsium arvense increased canola K concentrate. The experiment results show that in addition to competing weeds, through release of chemicals can be also inhibit on growth and physiological processes of crop.

Drought is a major a biotic stress that severely affects agricultural systems and food production. Nano silver penetrates in plant tissue easily and increase nutrient absorption. Because of nano – silver disinfected importance in agriculture, this research were conducted to study effects of seed disinfected in fungi of root symbiosis in three Factor Randomized Complete Block Design (RCBD) Disinfected of two genotypes of barley (hull and hulless) with different concentration nano silver (0, 50, 100 ppm and fungicide) in germination stage and planted in pot. Osmotic pressure were done with PEG6000 (0, -5, -10 and – 15 bar) in germination stage. Also, germination rate, root and shoot height, root and stem dry weight were measured. Seed disinfected planted with mycorrhiza and non – mycorrhiza and watered with hogland solution with PEG Y=-5 bar. At finally root and shoot height, mycorrhiza dependency, and root and shoot dry weight calculated. Result showed that in drought stress, disinfected seed with 50 ppm nano-silver, highest germination rate differently. In fungicide treatment were showed lowest seed infected. The ratio root dry weight /shoot of hulless barley seed with 100 ppm nano silver decreased differently. Symbiosis of mycorrhiza increased height root. Shoot height and ratio of shoot height / root with 50 ppm nano silver, symbiosis with mycorrhiza increased differently. Fungicide decreased mycorrhiza dependency and in drought stress condition in 100 ppm nano silver was lower differently than 50ppm.

Long season and high temperature during spring in hot and dry areas has led to tendency for autumn planting. A field experiment was done in 2010 at the Agricultural Faculty and Natural Resources of Saravan Research Field in order to evaluation of possible autumn planting of lentil (Lens culinaris Medik.) on yield and yield component. Experimental design was done as split plots based on randomized complete block design with three replications. The main plots and subplots included three planting dates' times (1 Nov., 18 Nov. and 2 Dec.), and five lentil genotypes (MLC 122, MLC 177, MLC 39, MLC 352, MLC 20) respectively. Results showed that the effect of planting date on all measured parameters (grain yield, plant height, pod number per plant, grain number per plant, two-grain pods, empty pods, 1000-grain weight, biological and economical yield and harvest index) was significant. The highest amount of grain yield was related to first planting date (1 Nov.), and dry matter production and grain yield decreased with delaying of planting date because the grain filling stage was synchronized with higher temperature of final stages of growing season. The effect of genotype on all measured parameters, also significant (p£5) and the MLC39 genotype had higher grain yield (34.11 g.m-2). The best correlation of grain yield was observed with number of seed per plant (r=0.59**), biological yield (r=0.81**) and number of two-grain pod per plant (r=0.63**). The interaction effect of planting date and genotype was significant and the highest grain yield (with average 59 g.m-2) was obtained at first planting date (1Nov.) and MLC39 genotype. The lowest yield was related to MLC20 genotype (8 g.m-2) at second planting date (18 Nov.) and there was no yield for third planting date (2 Dec.). Altogether the results of this study showed that early planting of superior genotypes during autumn cause to increase lentil yield in Saravan climate.

Chamomile is one of the most important medicinal plants in the world trade with many applications in pharmaceutical, cosmetic and sanitary industrials. In order to evaluate the genetic diversity of 26 landraces, collected from different regions of Iran, based on morphological and phenological characters, the experiment were conducted in augmented design with 6 controls and 3 replications. Results showed that characters of the economical yield, harvest index, fresh weight of 50 flowers and dry weight of 50 flowers had maximum phenotypic variation coefficients, respectively. The phenological traits had the lowest of variation coefficients. The genetic masses based on cluster analysis, were settled in five groups with different agronomic traits. Results also indicated that the masses intra-groups were different and the genetic diversity was not according to the geographical diversity. Analysis variance analysis for groups of cluster analysis showed that the differences among different groups for all of traits are significant.Factor analysis with principle component method using 14 characters three correlated factors were recognized justifying 82.37% of the total variation.The first, second and third were related to flowers yield, phenological traits and biological yield, respectively. According to the results, in order to increase the yield of dry flowers per plant, the traits such as economic yield, dry weight of 50 flowers, fresh weight of 50 flowers, harvest index and number of flowers per plant should be used as selection criteria.

Most inoculation studies have focused on free-living diazotrophs, although a few reports indicate rhizobia can act as PGPR. In order to evaluate nitrogen fixation ability of different strain of Rhizobium legominosarum biovar phaseoli in common bean, a randomized complete block design including 6 rhizobial isolates (L-100, L-41, L-75, L-216, L-54 and L-139 selected from different provinces by soil & water research institute), one nitrogen fertilizer (400 kg Urea per ha) and one control plot (without seeds inoculated and fertilizer) in four replication was carried out in two field (Dehaghan & Esfarjan) at Isfahan province in 2003. Results showed that significant differences were observed in seed and dry matter yield, total nitrogen absorption, number and weight of nodules and seed yield among seed inoculated with different strains and non-inoculated controls. In Dehaghan field, seed inoculation with L-75 strain and in Esfarjan field, seed inoculation with L-54 and L-139 strains increased dry matter yield, total nitrogen absorption, number and weight of nodules and seed yield. Results also showed that seed inoculation with some rhisobia isolates increased micronutrients absorption. In Dehaghan field, inoculation of L-216 and L-75 strains led to higher absorption of Cu and Zn. Some isolates could not promote nitrogen absorbtion.

Chamomile is a native plant in Europe and is famous due to use as a culinary and medicinal. In order to evaluation of agronomic traits and their relationship in different chamomile landraces, 20 landraces collected from different areas of Iran and five European cultivars were planted in an augmented design in Fozveh Station of Isfahan Agriculture Research Center. Several phonological and morphological characteristics were measured. Results showed that flower yield per plant, number of flower per plant and essential oil content had maximum coefficient of variation (CV) and phonological traits, number of ligulate florets, flower diameter and flower height had minimum coefficient of variation (CV). Correlation coefficient of flower yield per plant with yield components e.g. number of flower per plant (0.95**) and number of flowering branches (0.73**) was positive and high. Results of step-wise regression for flower yield per plant showed that number of flower per plant, 100 flower dry weight and number of flowering branches were entered to the model, respectively (R2=0.98). Factor analysis showed that 80.06 percent of data variations were determined by six independent factors. Genetic diversity was considerable among landraces especially for flower yield per plant and yield components.

To evaluate the genetic diversity and identify relationships among traits in 20 wheat genotypes, two experiments were conducted based on randomized complete blocks design with three replications, in two separate conditions of full irrigation and late drought stress, in two locations of Miyandoab and Hamedan during 2006-2007. Means comparison showed under full irrigation condition, genotype 2 with 8.980 t/ha, genotypes 2 and 13 under late drought stress condition with 6.800 and 6.900 t/ha, respectively had the greatest grain yield. Correlation coefficients between traits showed that grain yield had positive significant correlation with plant height (0.24**) and biomass (0.59**) in full irrigation, and with biomass (0.83**), awn length (0.49**), number of seed /spike (0.41**) and harvest index (0.25**) in grain filling stage stress condition. Grain yield showed negative significant correlation with days to maturity, too. Stepwise regression analysis showed under full irrigation condition, biomass and harvest index (R2=0.97) and in late drought stress condition biomass, harvest index and number of grains per spike (R2=0.97) had major effect on grain yield and entered to final model. Path analysis indicated that biomass had highest positive direct effect on grain yield whereas it had negative effect through harvest index on grain yield (in both conditions). In two environmental conditions, selection based on grain yield could be effective, biomass and harvest index were identified as traits that are important in grain yield variations and genotype 2 identified as the best genotypes for two conditions.

In order to investigate the effect of five seed density100, 200, 300, 400(and 500 grain m-2) on yield and yield components of wheat digits under rainfed conditions. A factorial experiment based on in a randomized complete block design with three replications was conducted at agricultural research station of Khorramabad in 2006-7 cropping season. The results showed that there was significant difference among cultivars for grain yield, but among the seed densities and for interaction effect of cultivars × seed densities on grain yield no significant differences were observed. Chamran cultivar had the highest grain yield (5895 kg ha-1) among the cultivars. The 400 seed m-2 had the highest grain yield (5449 kg ha-1) and Chamran cultivar in 400 seed m-2 treatment had the highest grain yield (6335 kg ha-1). The correlation between grain yield and biological yield, straw yield and number of spike m-2 was positive and significant, but correlation between grain yield and test weight and thousand kernel weight was negative and significant. The results of path analysis indicated that three characteristics including number of spike m-2, number of grain per spike and thousand kernel weight were main yield components for grain yield. The correlation analysis showed that the number of spike m-2 (r=1.55**) and number of grain per spike (r=0.99**) had positive and the highest direct effect on grain yield.

To evaluate the effect of intercropping of grass pea (Lathyrus sativa) and barley (Hordeum vulgare) in forage production and forage quality of a field trial was conducted at the research farm of the University of Birjand in the 1388-1389 crop year. For this purpose statistical factorial design was used in a randomized complete block with 15treatments and three replications.Treatments consisted of three low density (300 plant per square meter for barley , 500plants per square meter for grass pea), the average (400 plants per square meter for barley and 65 plants per square meter for grass pea), high density (500 plants per square meter for barley and 80 plants per square meter for grass pea), 5mixing ratio (25: 75, 50: 50, 75: 25, 100: 0, 0: 100 of barley and grass pea mixture). After forage yield harvest, forage, quantitative and qualitative performance of green pea and barley in pure and mixed cultures were studied.Results showed that different levels of plant density on evaluated traits had no significant effect on other traits except intercropping dry matter yield, ash percent and NDF.but the grass pea and barley forage quantity and quality were tested with different intercropping treatments. highest fresh forage yield was devoted to grass pea mono cropping with 22222kg/ ha and among the intercropping ratios of25: 75 (grass pea: barley) produced22, 088 kilogramsper hectare.Indices of intercropping forage ratio respectively, showed that the ratio of 50: 50 at average density of LER=1.32 and the mixing ratio. Forage quality analysis showed that all forage quality traits which affected with the intercropping ratios except crude fat were significant.The highest yield of protein was at the mixing ratio50: 50 (grass pea: barley) The effects of different ratios of mixed barley and grass pea were significant on measured traits. Also with increasing grass pea to barley cultivation system, the ash percentage and NDF were improved.

Salinity and its control is one of the main affairs that have collated since more than thousand years ago. Difficulties related to optimal germination and plant establishment is one of the most important problems for farmers in arid and semi-arid areas. This investigation was conducted to evaluate the effects of salt stress on seed germination of bread wheat cultivars; an experimental factorial in completely randomized design (CRD) with three replications. The experimental factors were 8 bread wheat cultivars with 4 levels of salt stress (0, 3, 6 and 9 gr/lit Nacl). The results showed that wheat genotypes as well as between different levels of salinity on radicle length (RL), plumule length (PL), ratio of radicle length to plumule length (RL/PL), coleoptile length (CL), seedling fresh weight (SFW) and germination percentage significant difference was observed (p£0.01). It was also revealed that the ratio of radicle fresh weight to plumule fresh weight (RFW/PFW) was infiuenced significantly by genotypes (p£0.01), but the effects of stress levels on this trait was significant (p£0.05).Interaction of genotype × salt stress levels on radicle length (RL) was highly significant. With increasing in the levels of salt stress all traits decreased except of RL to PL ratio. The highest correlation was obtained between RFW/PFW ratio and RFW (r=0.95). Cluster analysis, based on standardized data, classified the genotypes into three groups. Azar 2 was found to be highly salt tolerant as compared to the other genotypes and possessed higher values for all traits measured except SFW, RL to PL and RFW/PFW ratio.

In order to the fitness of five resistant and two susceptible wild oat biotypes to Acetyl coenzyme A carboxylase herbicide to freezing stress, an experiment was performed in factorial arrangement, based on completely randomized design with three replications at Ferdowsi University of Mashhad, Faculty of Agriculture in 2009. In this experiment wild oat biotypes exposed to seven freezing temperatures (-3, -6, - 9, -12, -15, -18 and -21oC). Potted plants were grown in natural conditions and maintaned for acclimation, until 3-4 leaf stage and then, the plants were frozen according to the freezing temperature (FT) regimes, plant survival percentage, determined by counting survived plant, lethal temperature for 50 percent of the plants (LT50su) was determined based on of survival percentage and reduce dry matter temperature 50 percent (RDMT50) after the end of recovery (three weeks after the freezing). The results showed that the effects of frost temperatures were significant (P£0.01) on wild oat biotypes survival percentage and LT50su and wild oat biotypes were significantly (P£0.01) different on survival percentage and LT50su parameters. Reducing the temperature less than – 12oC killed all of wild oat biotypes. Among wild oat genotypes, Mashhad sensitive herbicide and Khuzestan sensitive herbicide showed the highest and the lowest tolerance to freezing temperatures respectively based on LT50su and (RDMT50). The experiment showed that herbicide resistance in weeds can lead to change their biological characteristics such as freezing tolerance. Based on the results of LT50su parameter, wild oat resistant biotypes to freezing tolerance more than wild oat sensitive herbicide biotypes.

In order to evaluate the effect of different levels of drought stress and phosphorus fertilizer on some physiological traits and essential oil of sweet basil (Ocimum basilicum L.), a factorial experiment was carried out in completely randomized design in a greenhouse of College of Agriculture, University of Zabol, Iran in 2009. Studied factors were water deficit (drought) in 3 levels (100%, 80% and 60% field capacity) and 3 levels of phosphorus fertilizer (0, 50 and 100 kg per ha). The results showed the effect of water stress levels (p<0.01). Interactions between water stress and phosphorus fertilizer led to significant reduction (p<0.05) on leaf relative water content, but different value of phosphorus fertilizer did not cause significant difference in this trait. Percent of Shoot protein significantly affected by phosphorus fertilizer and water stress treatments protein percentage increased with increasing severity of water stress and its value was for control, mild and severe stress, equal to 1.15, 1.95 and 2.38 percent, respectively. Water stress have significant effect (p<0.01) on chlorophyll fluorescence. So that at the control, 80 and 60 percent field capacity chlorophyll fluorescence values was equal to 0.85, 0.74 and 0 /64, respectively. Amount of Chlorophyll (chlorophyll meter) in two stages 15 and 30 days after stress treatment on basil plants showed the lowest amount of chlorophyll was obtained in conditions of severe stress (60 percent field capacity) at 30 days after the water stress amount that it‘s be equal to 6.17. Totally it seems sweet basil at water deficit stress conditions, with high production of proline and carbohydrate execute drought tolerance mechanism, but this conditions lead to decrease of chlorophyll and increase of chlorophyll fluorescence.

In this paper, the effect of applying field magnetic crossing water for irrigating maize seeds (cv. Maxima) in the germination and establishment tests was studied. For this purpose, two separate experiments were carried out in faculty of agriculture, university of Zanjan (Iran), in 2011. The germination test was done for 10 days and the establishment for 20 days. Both experiments were done as factorial test in completely randomized design with 4 replications. The experiment factors were type of water including distilled water and well water and crossing and no crossing through the magnetic field. To irrigate treatments, it was used distilled and well water in usual state and after crossing from magnetic field with rate=0.1 Tesla. Length and dry mass of shoot, length and dry mass of root, percentage and rate of germination were measured and calculated in the germination and establishment tests. On the results, using magnetic water, in the germination test, increased shoot length, dry mass of shoot, dry mass of root, percentage and rate of seed germinations 17.95, 25.9, 22.22, 21.23 and 21.8 percent, respectively, compared with control treatments. Also, the establishment test results showed, irrigating treatments by using magnetized water had increasing effect on initial growth characteristic of plants, so that it increased plant shoot length, dry mass of shoot, dry mass of root and germination rate, respectively, 14.65, 20.87, 33.12 and 12.2 percent compared with control treatments. Considering that no material is added in irrigation water when crossing magnetic field, so magnetizing of irrigation water is a safe and environmental technology.

In order to study the effects of farm age, corm weight and different amount of manure fertilizer on corm yield and stigma yield of saffron (Crocus sativa L.), an experiment was conducted based on randomize block design with three replications, for different age of fields, in agricultural research field of Ferdowsi university of Mashhad in three years (2009 to 2011). Treatments were corm weight in 4 levels (>4, 4-8, 8-12, <12 gr), manure fertilizers in 4 levels (0, 10, 20 and 30 ton.ha-1) and farm age in 3 levels (1, 2 and 3 years). For planting corm (3.5 ton. ha-1) corm was used. Results were showed that the effect of farm age, corm weight and manure fertilizer on different criteria was significant (P<0.01) and the hieghest corm weight (15gr), stigma yeild (0.623 gr.m-2) and leaf dry weight (5.1 gr.m-2) was observed with 20 ton.ha-1 manure, corm weight of 8-12 gr in the field with 3 years age, whereas, the highest corm yeild (725 gr.m-2) was obtained with corm weight (>12gr), 30 ton.ha-1 manure in the field with 3 years age. An optimal stigama yeild obtained with 8-12 gr corm weight, 20 ton.ha-1 manure fertilizer in the field with 3 years age.

Seed yield, a quantitative character, is largely influenced by the environment, and thus has a low heritability. Therefore, the response to direct selection for seed yield may be unpredictable unless environmental variation is well controlled. The objective of this study was to examine the mathematical relationships between seed yield and its components by using a path analysis and ridge regression modeling approach to forecast the seed yield in seed production. To do this, a split-plot experimental based on randomized complete block design with three replication was conducted in 2004. Irrigation treatments were assigned to main plots, and two soybean cultivars were allocated to the subplots. Irrigationtreatments I1, I2, I3 and I4 were defined based on the cumulative evaporation of 60±3, 80±3, 100±3 and 120±3 mm, from pan (class A), respectively. The seed yield components considered in this study, were number of pods per plant (x1), number of seeds per pod (x2), number of seeds in plant (x3), pod-bearing nods in plant (x4) and seed weight (x5). Pearson correlation coefficients and path analysis of components x1 through x5 to Y showed that the strongest indirect effect on Y was x1 via x3 (the coefficients is 0.29), x1 via x4 (the coefficients is 0.24) and x3 via x1 (the coefficients is 0.24). All of the ridge coefficients were positive except x2 that in two levels of I1 and I4 irrigation treatments was negative. This result showed that number of seeds per pod trait in the soybean crop is very sensitive to the amount of water so that with the maximum and minimum amounts of water, its value was related to yield inversely. This study developed an original exponential model for estimating yield from the values of yield components under influenced different irrigation regimes. The model was statistically reliable. In the present trial, the genetic controls were more general than the environmental controls for x1 to x5. Therefore, we tentatively propose that x1, x3 and x4 were orderly more genetic and less environmental control than x2 and x5.

One of the factors that limits the canola planting area at arid and semi arid area is late season drought stress.This restriction is severed by hot and drought winds which lead to shattering and yield lose. One way to avoid from this limitation is releasing of early cultivars. To investigating about this, two winter cultivars (Okapi and Zarfam) and two summer cultivars (Hyola 401 and RGS003) arranged at RCBD design whit 3 replication at Garmsar Agricultural Research Station in 2011-2012 years. Each cultivar planted at normal and delayed planting date. The results showed that delayed planting did not affected on attributes such as pod per plant, seed per pod and seed yield significantly. However thousand seed weight, oil content and plant height were significantly different within cultivars. Interaction of planting date and cultivar had significant effect on plant height, height of first branch and thousand seed weight but seed yield and yield components did not affected by this interaction. Totally, since reducing the number of irrigation and early maturity of summer cultivars, they didn’t encountered with late season stresses and so delayed planting andRGS003 cultivar can be recommendable at this experiment conditions.

In this project, alfalfa nutritional requirement was studied in saline soils of Qom province. The experiment was conducted with 3 levels phosphorus (0, 100 and 200 kg Triple superphosphate /ha), 3 levels nitrogen (0, 250 and 500 kg Urea/ha splited for per cutting), 2 levels potassium (0 and 100kg Potassium sulfate/ha) and 3 levels salinity in irrigation water (6, 8 and 10 (dS/m)) as 4 factors in randomize complete block design, with 3 replications in 2 years. Results of this study showed that independent effect of nitrogen and phosphorous, resulted in the increase of alfalfa dry matter. with increasing salinity up to level 8 (dS/m), plant need to these fertilizers increased. In the highest salinity level (10dS/m) a reduction in yield was observed, so that fertilizer application had no significant effect on yield. In none of years, independent effect of potassium on yield was not significant. With increasing salinity levels, concentration of macronutrients including N, P, and K and nitrate alfalfa decreased. Application of nitrogen and potassium fertilizers caused an increase of nitrate (NO-3) concentration in plant.

Two separate experiments were carried out with the aim of investigating the effect of drought stress on of germination, morphological and biochemical traits ofOryza sativa L. cv.Hashemi in vegetative growth at the Research Center for Plant Sciences, Ferdowsi university of Mashhad, in 2011. At first experiment, different level of drought stress (0, -2, -4, -6, -8, -10 bar) by polyethylenglycol 6000 were studied on germination of rice. The number of germinated seeds was counted each day and was sampled after ten days. Then, the percentage and rate of germination and length and dry weight of shoot and root were determined. The next experiment, levels of drought stress including control (field capacity), 20, 40, 60, 80 of field capacity on vegetative growth rice plantlets were investigated. Plantlets were transferred to the plastic pots and the sampling of seedlings was carried out 22 days after planting. Both experiments were conducted in Completely Random Design with three replications. The results showed that levels of drought had a negative effect on the percentage and rate of germination and length and dry weight of shoot and root. In vegetative stage, height, leaf area and root only in 20% field capacity treatment and amount of prolin and potassium in shoot in all drought levels were significantly decreased. We concluded the level of drought stress in 40, 60, 80 field capacity have not sensible effect on vegetative growth Oryza sativa L. cv.Hashemi.

In order to study the effects of nitrogen and phosphoruse application rate and methods on wheat yield, an experiment was performed as factorial, based on completely randomized design with three replications at Research Farm, Faculty of Agriculture, Ferdowsi University of Mashhad, in 2009. Treatments included of nitrogen rate at three levels (100kg ha-1, 200 kg ha-1, 300 kg ha-1), phosphorus rate at two levels (100 kg ha-1, 200 kg ha-1) and two levels of application methods (Broadcast and Band). Phosphorus and nitrogen sources for fertilization were respectively super phosphate applied before wheat sowing and incorporated with soil and urea, applied in two phases (50 % pre plant) and (50 %) near wheat shooting. Results showed that the effect of fertilizers application methods were significant (p£0.01) on wheat yield increasing. Band application of phosphorus and nitrogen were increased biomass and seed yield of wheat with nine and 15% respectively compared to their broadcast application. The interaction between the effects of nitrogen and phosphorus application rate with phosphorus and nitrogen application methods, showed that band application of fertilizers and the rate of application of 200kg/ha phosphorus and 300kg/ha nitrogen were the best methods in wheat yield improvement. In conclusion these results indicate that modifying fertilizers application methods and changing the rate of application, have important role in increasing fertilizers use efficiency.