JOURNAL OF RESEARCH IN CROP SCIENCES
Year:2013 | Volume:5 | Issue:18|Papers Count:10

In order to study the effects of pruning lateral branches on yield and yield components of four varieties of castor bean plant, an experiment was conducted at the Agricultural Research Station of Saatlo in Uremia during 2010 growing season. Experimental design was a split plot based on completely randomized block design with three replications. The main plots were varieties of castor bean (80-23, 80-29, 80-12-1 and 80-17) and sub plots included three types of pruning (no pruning, pruning of two lateral branches and pruning of four lateral branches). The plant characteristics were studied in terms of main panicle length, number of grain per plant, grain weight per main panicle, 100 grains weight, grain yield, weight of main panicle, weight of grain per plant, biological yield, harvest index and oil yield. Results of the data review showed that the effect of varieties was significant on all of characteristics. Also the impact of pruning and interaction of two factors of variety had significant effect just on grain weight of main panicle and its weight. According to the results, the variety of 80-12-1 and pruning of four lateral branches with highest grain yield (1497.5 kg h-1), biological yield (14200 kg h-1), and oil yield (805.45 kg h-1) in the region is recommended for cultivation.

To study the effect of drought stress on yield and grain yield components of clover, an experiment was conducted at the agricultural research station of Saatlo in Uremia during 2009-10. Experimental design was split plot, completely randomized block design with three replications. The main plots consisted of normal and stress irrigation treatments and the sub plots included 17 species and varieties of yearling clover. Clover genotypes in terms of traits such as spike weight per plant, seed number in plant, thousand grain weight, grain yield and harvest index were studied on the farm. Results of the data review showed that the effect of varieties on all the traits were statistically significant at the 1% level. Irrigation factor on thousand grain weight was significant at the 1% level and on both traits spike weight, seed number per plant and grain yield were significant at the 5% level. The interaction of two factors irrigation in cultivars, on seed number per plant, were statistically significant at the 5% level, and on the spike per plant and grain yield traits, were statistically significant at the 1% level. Also, maximum grain yield was obtained for genotype No. 11 with normal irrigation (164.11 kg ha-1) and with drought stress (115.12 kg ha-1). The results of this study showed that genotypes 2 and 11, the T. Resupinatum can be introduced as high yield in genotypes in drought stress.

To investigate the effect of nitrogen and potassium fertilizers and Rosasol complete fertilizer on yield and specialities of vegetative in 21 Burley Tobacco, a factorial experiment based on randomized complete blocks design with 2 fertilizer factors with 3 replications was conducted in Chaypareh in 1390. Levels of fertilizers used, were: first factor included 3 fertilizer levels 750, 950 and 1150 gr complete fertilizer (Rosasol) per cubic meter of water of float system and second factor included: 3 fertilizer levels1-300 kg Potassium of potassium sulfate source with 200 kg Nitrogen of ammonium nitrate source per hectare. Dry leaf yield applications, stem height, stem diameter and number of leaf on the plant, stem humid weight and harvest index was studied. The results showed that effect of nitrogen and potassium on dry leaf yield, stem diameter and stem height and wet stem weight and harvest index had significance in 1% probability levels. Effect of Rosasol fertilizer on the stem humid weight was significant in 5% probability levels. But the effect of treatments on the number of leaf in bush wasn't noticeable. The effect of consumption of 450 kg potassium with 200 kg nitrogen per hectare showed that the maximum yield of dry leaf and stem diameter, stem height and stem humid weight were mean 6471 kg per hectare and 52.98 mm and 211.7 cm and 4304 gr per meter square and consuming of 450 kg potassium with 100 kg nitrogen showed maximum harvest index that were 52.92%. To consume 950 gr Rosasol fertilizers per cubic meter water of pool in float system 3876 gr showed maximum amount of stem humid weight per meter square.

Currently, the effect of heavy metal pollution on plants, animals and human being is one of the most important worldwide environmental problems. Finding a way to reduce the heavy metals toxicity can be very useful. This study investigated the interaction of cadmium (as a heavy metal and stress factor) and salicylic acid (as an antioxidant and antistress) on some physiological parameters of sunflower plants (growth parameters, amounts of chlorophyll, protein and proline) as factorial with a completely randomized design with four replications in greenhouse conditions. Sunflower plants were exposed to CdCl2 treatments (0, 50,100,150 and 200 mM) and then were treated with salicylic acid (0, 250 and 500 mM) as foliage spraying. The chlorophyll content was measured in leaves. After harvesting of plants, growth parameters were measured and amounts of proline and protein were measured. Statistical analyses also showed excess Cd reduced photosynthetic pigments (chlorophyll a, b and a+b) of sunflower leaves and salicylic acid increased them. However, Cd´SA interactions on Chl a, Chl b and Chl a+b contents of leave were not significant (ns). Statistical analyses showed excess Cd reduced growth parameters (fresh weight and number of leaves) and SA increased them compared with the control. Maximum reduction in these parameters was at 200 mmol Cd and 0 mmol of SA. Proline content in the leaves increased under Cd stress and decreased by SA. Cd´SA interactions on proline content were significant. Protein content in leaves of sunflower is shown in decreasing trend with increasing concentrations of Cd .Exogenous application of SA increased the amount of protein in sunflower plants exposed to Cd stress. Cd´SA interactions on protein content in leaves were significant. Exogenous application of SA appeared to induce an adaptive response to Cd toxicity including the accumulation of organic solutes leading to protective reactions to the photosynthetic pigments in sunflower. This study showed that treatment with SA alleviated the inhibitory and toxic effects of Cd in sunflower plants.

To study the effects of planting methods and corm density on yield and some agronomic traits in saffron (Crocus sativus L.) in Shahr-e-Rey region, a field experiment was carried out in split plot design on the basis of randomized complete blocks design with 3 replications during 2011 at research field of Islamic Azad University, Shahr-e-Rey Branch. Planting methods in 2 levels (Furrow and flat plots method) as main factors and corm density in 4 levels (2.5, 3.5, 4.5 and 5.5 cm corm distance on rows) as sub-factors. Esfahan ecotype was used as experimental variety. The Results indicated that, effect of planting method was significant on all experimental traits, the maximum dried saffron yield was observed in flat plots method. The effect of corm density was significant on flower number, fresh and dry flower weight and yield. In this case the highest saffron yield with 3.21 conducted in 2.5 Cm corm distance on each rows (160 corm in each m2) and the lowest one with 0.75 was observed in 5.5 cm distance between corms(72.72 corm in each m2). So the flat plots method and corm density increase gained the maximum saffron yield. Interaction effects on all experimented traits did not show any significant difference.

In order to study the effect appropriate plant density and of different levels of irrigation on yield and yield components of maize, a study was conducted at the Agricultural Research Station of Islamic Azad University of Tabriz in 2011.The experiment was carried out in a split based on a randomized complete block design with three replications. Different irrigation levels as main factor in 4 levels, including irrigation after 50, 100, 150 and 200 mm evaporation from class A evaporation pan and different levels of plant density as the subsidiary factor including 8.9, 6.7, 5.4 and 4.5 plants per square meter, were considered. Experimental results showed that interaction of irrigation level and plant density on Characteristics such as shoot dry weight, number of kernel/ear, 100 kernal weight and harvest index was significant, so that with increase in irrigation level and decrease of plant density, other characteristics were decreased. Among irrigation levels the maximum grain yield was at level of 50 mm evaporation from evaporation pan and the minimum grain yield was at the level of 200 mm evaporation from evaporation pan. The maximum yield and harvest index was in plant density of 6.7 plant/m2 and 741.1g/m2. With increase in irrigation period in each level of maize growth caused noticeable decrease in yield and kernel/ear and this decrease was Effect of irrigation and plant density on grain yield and plant height were significant. The irrigation treatments, respectively, the highest and the lowest grain yield in treatments 50 and 200 mm evaporation from pan evaporation rate of 745.12 and 347.1 grams per square meter, respectively. The highest grain yield and harvest index of density 6.7 plants per square meter of 741.1 grams per square meter, respectively. Increase in irrigation period in each level of maize growth caused noticeable decrease in grain yield and number of kernel/ear, and this decrease was intensified when planting density increased.

When current photosynthesis in the flowering stage in hindered by drought stress and heat illness, the reservoir of the stalk acts as an important source in filling the grain. In this research soluble sugar associated with single plant yield and yield components of different wheat lines under drought stress conditions was studied in a pot experiment. Ten bread wheat cultivars were grown under different levels of irrigation in the pot based on a randomized complete block factorial design. During the grain filling stage, the sugar content of the leaves and stems of the original sample of 10 genotypes of spring wheat flag leaves were measured under normal and stress conditions. Although there was a significant difference between the lines in terms of soluble sugars drought conditions had significantly negative correlations between yield and leaf sugar which may indicate that the kernel limits destination is in compliance with soluble carbohydrates. Between different parts of the stem weight there were not significant correlations with the performance that might be the case that stress increase in glucose transport form stalk to grain.

In order to study the various levels of irrigation and differentiation and maturity processes on seed vigor of two wheat cultivars, an experiment was carried out in Agricultural Research Center of Miandoab in 1387–1388. The experiment was conducted according to split-split plot based on completely randomized block design (CRBD), with four replications consisting four irrigation levels (70, 100, 130, and 160 bcA) and two wheat cultivars (Zarin and Shahryar) and ten harvesting times. Seed harvesting was carried out in seven days interval manner from 20 – 83 days after flowering. In this experiment, the weight of thousand seed, dry weight of seedling, germination rate, electrical conductivity of material seeped from the seeds, percentages of viable seeds and seed humidity was measured to determine seed vigor. The results of analyzed data indicated significant difference within irrigation levels in weight of thousand seeds and germination rate at %1 level. In addition, effects of harvesting times on all measured traits were significant in at %1 level. Interactions effects of irrigation levels ´ cultivar, on germination rate at %1 level and also on dry weight of seedlings and on electrical conductivity of material seeped from the seeds were observed on %5 levels. In the case of irrigation levels ´ harvesting times, only germination rate, was significant and in the case of cultivar ´ harvesting times, dry weight of seedling, weight of thousand seeds and germination rate were significant in %1 level. The effect of irrigation levels ´ cultivar ´ harvesting times, on electrical conductivity of material seeped from the seeds and germination rate was significant at %1 level. There was significant positive correlation between percentages of viable seeds, dry weight of seedling, germination rate and weight of thousand seeds, but significant negative correlation existed between electrical conductivity of material seeped from the seeds each measured traits. The results also indicated that cultivar Shahryar had more vigorous seeds and was superior to cultivar Zarin under stress conditions. Physiological maturity was observed between 55 – 62 days after flowering, which was suitable for seed humidity (14 – 15%) was harvested at the seventh stage (62 days after flowering), therefore it is suggested as a suitable time for harvesting.

In the current survey, based on the pot culture method, an experiment was carried out at Randomized Complete Block design using SA pretreatment in three levels of (0M, 10-5, M, 10-4M) then applying cadmium in three levels of (0, 6, 12 mg/kg), totally in 9 treatments and three repetitions for every treatment, the growth and some biochemical detectors of the pepper plant (Capsicum annuum) were studied. The results revealed that the single cadmium treatment decreased the total chlorophyll and increased chlorophyll b and carotenoids. The single treatment with SA led to an increase in the amount of chlorophyll a, and carotenoid whereas it had neutral effect on the total chlorophyll content. In the joint treatments, in both levels of SA treatment, the raise in the amount of cadmium led to a boost in these parameters. In SA treatments with single cadmium as SA concentration improved, the amount of proline cadmium in root, stem and leaf did too. In the joint treatments of both SA concentrations with increased proline concentration, cadmium of root stem and leaf decreased. In single Cd treatments the stem protein quantity increased firstly and then decreased as the Cd concentration increased, while it was revealed in the same treatments there was an increase in 6 mg in the leaf. In SA single treatment the quantity of protein in root, stem and leaf boosted as SA concentration increased. In joint treatments in 10-5M of SA, Cd concentration boosted the root protein and in10-4M in stem and leaf it was increased. The results made it clear that in without SA treatments by increased Cd concentrations from 0 to 6 and 12 mg, the MDA amounts was built up. In single treatments with SA, it had no effects on MDA with 10-5 M density to observer, but the amount of M improved its quantity. In joint treatments of the treated plants with 10-5 of SA an increase in the concentration of Cd led to decrease in its amount.

In order to consider the dates of planting effect and foliar application with growth stimulants in spawning and growing of sunflower, we performed an examination in full pile district style with 3 times repetition in 2010 cropping year, in agricultural and natural resources institute, Uremia, Iran. The obtained results proved that foliar application with growth stimulants and different dates of planting had a great effect on most of the cases studied statistically. In order to better use of environmental condition the greatest bush height connected to alternate effect foliar application of Daljin and first planting date. With a view on grain yield the greatest amount related to Daljin care and second planning date, and the lowest amount related to control treatment with first planning date. In terms of humus and oil treatment first planting date (27 April) allocated the maximum amount to themselves. Totally, it was concluded that if the aim is obtaining the maximum yield of sunflower oil, Daljin humus treatment and second planting date would be recommended.