مجله تولید گیاهان زراعی
سال نهم شماره 2 (تابستان 1395)

Seed deterioration and waterlogging stress are factors that lead to lower growth. On the other hand, seed deterioration may affect plant growth that plant growth can be used to quantitatively describe the components of growth analysis.
In order to investigate the mechanisms that lead to the reduction of growth and interaction of these two factors, a factorial experiment in a randomized complete block design (3 treatments seed quality for 0, 72 and 144 hours of accelerated aging and 4 treatment involves waterlogging 0, 5, 10 and 15 days of flooding) in 4 replicates. In this research, wheat seeds (Daria), first in the laboratory for seed quality treatments, were worn by accelerated aging.
The results of laboratory studies showed that seed deterioration slowing, germination and seedling growth reduction is achieved. In the greenhouse, the plants during the tillering stage control (to waterlogging stress) and heading stage control (after waterlogging stress) were collected. The tiller control, by increasing the number of plants decreased seed longevity found. The heading control between different levels of seed aging, the number of tillers per plant and seed deterioration were treated with seed deterioration increases, the number of plants was reduced, but increased the number of tillers. Tillering stage control (to waterlogging stress) that cover the whole plant is not land, leaf area and dry weight depends on the density and the deterioration of seed density decreased, but only the leaves of waterlogging stress reduced pot. At tillering control seed decay with increasing relative growth rate significantly decreased but increased in stages to control the seed deterioration relative growth rate significantly increased. One of the reasons for the increase RGR in plants from the seeds of the decline could be due to offset slow canopy closure due to low density of plants in this plant. After waterlogging stress relative growth rate, net assimilation rate, leaf area ratio and leaf weight ratio to treatment were significant seed deterioration, but to waterlogging stress and interactions were non-significant decline of seed and waterlogging stress.
Seed deterioration treatments, Waterlogging stress and their interaction were effective on the growth response mentioned in wheat

In order to investigate the impacts of winter cover crops and their removal methods on qualitative yield and income of tobacco (K326), an experiment was conducted as a split plot based- randomized complete block design with four replications. The main factor was cover crop (inclusing wheat, WM; Berseem clover, BC; hairy vetch, HV; and bitter vetch, CP) and sub-plots included removal treatments (Paraquat髩, PM; Glyphosate㋩,GM; Moving㋩, MM).
Materials ad On December 2011, the cover crop was sown in the farm and on 24 April 2011, using herbicide and stem cutting; they were eliminated and remained on the land surface as mulch. On late February 2012, tobacco was sown in seedbed and on 8 May 2012, the those transplants with 15-20 cm height, were moved to the farm and were transplanted into the much. 40 days after transplanting, the first leaf harvesting was conducted and their sugar, nicotine, phosphor, nitrogen, potassium, and chlorine contents were measured. Also, leaf yield was calculated.
Cover crops and mulch management had no significant effect on the nicotine and total leaf nitrogen content. Interacted effect of both factors was significant on the sugar content, as the maximum (15.95%) and minimum (11.27%) levels were related to WM-MM and HV-PM, respectively. Results revealed that sugar content in WM-GM, WM-PM and WM-MM decreased 22, 18 and 22% compared to control. The maximum and minimum potassium levels were related to WM (2.53%) and HV (2.15%), respectively, while related values were as 1.29% and 0.8% for phosphorus content, which were related to BC and WM, respectively. Combined treatment of mulch management × cover crop had significant effect on the tobacco fee.
Overall results revealed that cover crops along with mulch management could be considered as an appropriate alternative to improve qualitative characteristics of tobacco along with increasing the fee and farmer’s income. Also could be a proper alternative for chemical inputs to move toward sustainable agriculture goals.

Evaluation of the grain yield and yield components and also morphological traits can help to identify strategies for selection of resistant cultivars and increased crop yield production under heat stress condition. To this end, in experiment to evaluate of grain yield and yield components on 42 rice lines tolerant to heat stress from International Rice Research Institute (IRRI).
An experiment was conducted based on randomized complete block design (RCBD) with three replications plus Hoveizeh cultivar as control during 2013-2014 in Agricultural Research and Natural Resources Center of Khuzestan province, Iran. The evaluated eight characters were: degree of maturity, growth period, number of tillers per square meter, number of grains per panicle, number of hollow grains per panicle, 1000 grain weight, fertility percentage and grain yield measured on the basis of the standard system of International Rice Research Institute. As the degree of maturity of the product of two traits of fertility percentage and 1000 grain weight were measured in each trial.
Research simple of traits variance analysis showed there were significant differences in effect of cultivar for all traits except number of tiller per square meter that this result showed that diversity of the lines and cultivar for using in the study. Number of tillers per square meter and number of grains per panicle in front of grain yield imported in regression equation that these traits of positive and significant correlation with grain yield. Path analysis showed that the number of grains per panicle with correlation coefficient of 0.337 had the higher direct effect than number of tillers per square meter with correlation coefficient of 0.186 on grain yield. Principal component analysis of the first two components explained 74% of the total diversity. In this analysis desirable characters such as fertility percentage, grain yield and degree of maturity in the first component have positive coefficient traits which increase first component, and also 1000 grain weight with negative factor coefficient in second component, so first component increased and second component decreased. Cluster analysis, case of study cultivar and lines resolved in three groups. In the first cluster, lines such as: 1, 34, 54, 35, 39, 21, 33, 40, 25, 28, 9, 10, 15, 29, 32, 31, 30, 36 and 44 as well as in the second cluster, lines such as: 3, 24, 4, 19, 5, 7, 6, 55, 14, 23, 16, 17, 18 and 20 and in the third cluster, lines such as: 8, 50, 52, 43, 41, 45, 11, 13, 12 and 26 were included. In the first cluster desirable lines were 40, 35, 34 and 25 and in second cluster undesirable lines were 11, 12, 13, 26, 41 and 45.
Significant differences in effect of cultivar for all traits except number of tiller per square meter that this result showed that diversity of the lines and cultivar for using in the study. According to graph of biplot the first cluster was as best cluster and third cluster was as worse. Discriminant function showed truth grouping at 95%.

Plant appropriate nutrition is one of the most important factors in improving the quality and quantity of product. Providing adequate and balanced of plant nutrients is essential for achieving maximum potential production. Potassium is one of the essential elements to plant’s growth. Therefore, knowledge of soil potassium status is so important in order to optimum usage of potassium fertilizers. There are several methods to measure soil K. Ammonium acetate method to extracting the plant usable potassium is not efficient in all kinds of soils and high cost of sodium tetra-phenyl boron is also the negative point of this method for extracting numerous soil samples.
Considering this matter that Extraction method with ammonium acetate in Loess soils with high specific surface area in Golestan Province is less accurate compared to the method of sodium tetra-phenyl boron extraction; and on the other hand sodium tetra-phenyl boron extractio is time-consuming and costly; We have to select a different method to estimate K which is more accurate and time and costs are lower. The aim of current study was to determine the feasibility of a low-cost index as potassium excess in determination of soil available potassium in some rain-fed wheat in Golestan province with limited usability of ammonium acetate. Forecast wheat yield with using artificial neural network in a farm limited unit in order to achieve the ultimate goal, the application of potassium excess doneto estimate fertilizer requirements.
This study was done in a piece of land (922m2) in Gorgan University of Agricultural Sciences and Natural Resources Farm one. Plots were divided into 40 plots and wheat (var., line17) seeds were drilled. During one stage (before planting) soil samples from each of 40 plots harvested and transferred to the laboratory for further analyzes. At the time of harvest, plants were harvested each plot separately. Potassium was measured by three methods of ammonium acetate, sodium overload and sodium tetra-phenyl boron. Artificial neural network model was used to estimate the predicated yield. In this model output yield and potassium intake was measured by three methods mentioned.
According to the results, the correlation between yield and the three extractor ammonium acetate, sodium tetra-phenyl boron and potassium excess, are 0.62, 0.78 and 0.77 respectively. Accordingly, the extraction method with an overload of potassium, has higher correlation with grain yield, than ammonium acetate extraction method, and has close results with extractor sodium tetra-phenyl boron.
The studied soil extraction method with an overload of potassium compared to the current (in the region) by ammonium acetate extraction has greater accuracy and efficiency. As a result of using less fertilizer and potassium excess not only increase the yield per unit area will be sought, but also will reduces environmental pollution due to excessive use of chemical fertilizers.

Sustainable agriculture is a compilation of knowledge that can be long-term management of biological, environmental and economic value of a good cause. One of the ways to move towards sustainable agriculture, use a mixture of different species of plants in agriculture. In many parts of the world mixcropping as part of the management of agricultural ecosystems accepted and Has certain advantages in terms of the degree of variability in time and space. Intercropping can be effective as an important factor in sustainable agriculture and according to the different needs of the species in the mix, so the output will be less competition. Research has shown that the superiority of mixed agriculture due to more complete use of growing resources. The aim of this study, was to investigate of growth criteria, yield and physiologic efficiency and nitrogen appear recovery of flint corn to simultaneous cropping of legumes and different levels of urea levels.
This study was carried out at field of agricultural research center of Markazi province during growing season of 2012-2013. A factorial arrangement based on randomized complete block design with three replications was used. Nitrogen manure levels [N0= without urea (Control), N1= 75 kg ha-1 of urea, N2= 150 kgha-1 of urea, N3= 225 kg ha-1 of urea) and Simultaneous cropping treatment, (S1= Cultivation of corn, S2= Cultivation of corn chickpea, S3= Cultivation of corn cowpea, S4= Cultivation of corn mung bean) were assigned in plots. Each sub plot consisted of 4 rows, 6 m long with 60 cm between rows space and 20 cm between plants on the rows and S.C 704 hybrid was used. In this study characteristics such as: height of ear, nitrogen physiological efficiency of corn, dry weight of cob and husk, number of branches per legumes, number of grain per legumes, harvest index of corn, forage weight of corn legumes, nitrogen appear recovery of corn and grain yield were assessed.
Results indicated that the effect of different levels of urea was significant on the characteristics such as: height of ear, nitrogen physiological efficiency of corn, dry weight of cob and husk, number of branches per legumes, number of grain per legumes, harvest index of corn, forage weight of corn legumes, nitrogen appear recovery of corn and grain yield. The maximum and minimum nitrogen physiological efficiencies (22.75 and 4.38 %) were obtained in 225 kg ha-1 urea corn and 75 kg ha-1 urea corn treatments, respectively. The maximum and minimum grain yield (8.1 and 4.5 ton ha-1) were obtained with the (225 kg ha-1 urea corn) and (without urea Cultivation of corn mung bean) treatments, too.
Therefore, the application of integrated plant nutrition can increase nutrient use efficiency and producing products with greater quality and quantity. Also, by reducing the use of chemical fertilizers and leaching by reducing the amount of the tremendous waste, reduce environmental pollution of surface water and groundwater. As a result, production continuity and sustainability of agriculture and natural ecosystems will be very important.

In order to evaluate the delay cropping on yield and yield component of two canola cultivars and selecting the best genotype and row spacing, an experiment was conducted at three years (2007, 2008 and 2009) in Gorgan Research Station. This experiment was arranged in spilt-factorial based on randomized complete block design with four sowing dates (28 Oct., 12 and 28 Nov. and 12 Dec.) as main plot and row spacing (12 and 24 cm) and cultivar ( RGS and Hayola 401) as subplot in three replications. Growth stage, number of sillique per plant, number of seed per sillique, seed yield and grain oil content (%) was recorded. Results showed that delay cropping had different effect in three years and delay planting had higher risk during dry years. In normal years seed yield reduced 27 Kg ha-1 per one day delay in sowing. Average seed yield of three years at different sowing date showed that Hayola produced higher yield (3287 Kg ha-1). Seed yield of Hayola and RGS reduced 379 and 410 Kg ha-1 per ten days delay in sowing date. Relationship between mean air temperature during flowering and maturity showed that the effect of increasing temperature on seed number (351 Kg ha-1 loss) was more than seed weight (100 Kg ha-1 loss). Ten days in planting date increased oil percent (1%). In general, in delay planting Hayola cultivar is recommended and increasing row spacing did not have significant effect.

Integrated weed management approaches can help to decline costs weed control and improve its condition. Critical period of weed control (CPWC) is defined as the best time for weeding. If CPWC is recognized we can accurately use herbicides and prevent environmental pollutions. Beginning and duration of CPWC despond on some agents such as crop and weed traits, environment and agronomical factors. With respect to inexistence data about the effect crop rotation on the CPWC this study was done.
In order to determine effect two different crop rotations (wheat – canola and soybean-canola) on the critical period of weed control in rape seed, two experimental designs were performed for the first and second rotation in 2011 and 2012, respectively. These studies did in the suburban of Galugah region in randomize completely block format with three replications. Treatments included periods of weed management on the canola growth stages(five weeding and competition levels up emergence , two leaf stage , four leaf stage , eight leaf stage , flowering stage plus two control treatments).
Findings showed canarygrass dominated in both rotations. Species diversity in soybean-canola rotation by using Shannon index (H= 0.69) was higher than wheat-canola (H= 0.45) .Canola yield was 4060 and 2280 kg ha-1 in the wheat-canola and soybean-canola rotations, respectively. Further yield in the first rotation can be related to positive role of organic matter which was more in the soil and its influence on the most important yield component that was number pod in each plant. The CPWC for wheat- canola rotation was between 161 and 354 days after planting(DAP) (emergence to six-leaf stage) and between 65 to 920 DAP(planting up maturity stage), using 5 percent acceptable yield reduction.
CPWC in soybean-canola rotation relative to wheat-canola rotation begined sooner and its duration also was longer.

In the country, reducing water resources and increasing water losses in the various methods of surface irrigation, has increased attention, super drip irrigation method, especially drip tape irrigation. One of the techniques are used in cultivation of early sweet corn, the use of plastic mulch. Using this technique, the reserve temperature conditions for plant growth and early maturity, resulting in timely delivery of product to the target market. The use of germinated seedlings in the greenhouse and move it into the plastic on the farm, in addition to reducing water consumption, will double its precocity. In order to evaluate yield and some morphological characteristics of sweet corn with use of different irrigation levels and cultivation techniques under plastic mulch, an experiment was carried out as split plot in randomize complete blocks design with three replication in Faculty Agriculture, Research Field Station of Yasouj university at 2015. The main factor consisted of irrigation in three levels: 100 percentage of water requirement (I1), 75 percentage of water requirement (I2), 50 percentage of water requirement (I3) and the sub factor was including cultivation techniques of sweet corn in six levels: seed cultivation of sweet corn under plastic mulch at 4 April (CT1), seedling cultivation under plastic mulch at 4 April (CT2), seed cultivation to conventional method of sweet corn at 5 May (CT3), seed cultivation of sweet corn under plastic mulch at 5 May (CT4), seedling cultivation of sweet corn under plastic mulch at 5 May (CT5) and seedling cultivation to conventional method of sweet corn at 5 May (CT6). The result showed that interaction irrigation and cultivation techniques were significant on traits ear yield, canned yield, water use efficiency fresh ear, forage yield and biological yield. Maximum ear yield were obtained in treatments I2CT1, I1CT1, I2CT2 and I1CT2 equal 1442, 1441, 1369 and 1351 grm-2, respectively. Minimum ear yield was obtained in I3CT3 equal 706 grm-2. Maximum canned yield were obtained in treatment I1CT1, I2CT1, I1CT2 and I2CT2 equal 558.7, 551.1, 536.2 and 527.4 grm-2, respectively. The used of seedling, accelerated plant growth and development. Maximum water use efficiency fresh ear were obtained in treatment I2CT2, I2CT1, I3CT2 and I3CT1 equal 2.21, 2.18, 2.16 and 2.14 kgm-3, respectively. With increasing of water consumption to decreased water use efficiency fresh ear. So, to use of drip tape irrigation along with supply the 75 percentage water requirement with achieve acceptable performance, had following the maximum water use efficiency. Maximum forage yield and biological yield was in I1CT1 equal 2008 and 3399 grm-2 and minimum forage yield and biological yield was in I3CT6 equal 1237 and 1947 grm-2 respectively. The effect of irrigation were significant on trait ear length and the effect of cultivation techniques on trait plant height. Maximum ear length in treatment 100 percentage water requirement were equal 20.3 cm and minimum ear length in treatment 50 percentage water requirement equal 17.6 cm. Maximum plant height was obtained in treatment seed cultivation on conventional method under plastic mulch at 4 April. If there are water restrictions, use of treatment 75 percentage water requirement of sweet corn with plastic mulch would be desirable to maximum yield produce.

Making a reliable prediction of drought index status for the future is one of the major elements in a successful water resources management particularly under climate change processes, including increase in atmospheric carbon dioxide concentration, temperature and fluctuations in rainfall. The present study aims at assessing drought trend under changing climate conditions in some locations of Fars province.
This study was conducted in six locations of Fars province (Shiraz, Lar, Abadeh, Darab, Eghlid, Fasa). In the current study, two general circulation models (IPCM4 and HadCM3) under three emission scenarios (A1B, B1 and A2) were applied during three time periods of 2011-2030, 2046- 2065 and 2080-2099. LARS-WG program was employed to assess rainfall, maximum and minimum temperatures during the mentioned periods and in different emission scenarios. AI (Aridity Index) was used to study drought pattern in study locations.
Results showed that the impact of climate change on AI was a result of increasing temperature and evapotranspiration (ET) as well as decreasing cumulative rainfall which consequently reduced AI in all locations, scenarios and time periods compared to the baseline (i.e. locations would be drier in the future). There was no difference between climate models, scenarios and time periods in terms of ET. Generally, there will be a substantial increase in ET in Fars province in the future as a result of rising temperature which is highly correlated with ET. Results also revealed that the highest variability in AI was observed in Lar under three scenarios. In B1, fluctuation in AI was lowest amongst study locations and ranged from -55 to percent while it was -100 to 힝 in the other two scenarios compared to the baseline.
Results of the current study indicated that a reduction in AI in Fars province would be observed under future climate change. There will be a substantial increase in AI in Fars province in the future as a result of rising temperature which is highly correlated with ET. Drought spatial map also portrayed that drought would be intensified as the time period became closer to 2090 in all locations. According to the interpolations map, almost the entire province will be included in dry class category in 2090 under A2. Overall, it is concluded that under all emission scenarios and time periods, the drought will be intensified in the entire region of Fars province due to an increase in ET and a decrease in rainfall.

Review and goals: The ajowan(Carum copticum) is a medicinal plants from Apiaceae family that seeds contains 2-4% of volatile oil. 9-17 of chemical composition of ajowan essential oil have been reported(2), it have antibacterial and antioxidant activity of it caused to preserve the food materials(1). The application of chemical fertilizer leads to environmental pollution and ecological disaster (13). The proper approach to solve these problems is the use of sustainable agriculture fundamentals in agro ecosystems, that biological fertilizer such as vermicompost and Alkazotplus and Humic acid could be effective for these issues.In order to mentioned issues, the goal of this research was the examination of the effects of different fertilizer resources on essential oil of ajowan and soil properties in Ahvaz condition.
Material and a field experiment was conducted at the Agricultural Research Station of Shahid Chamran University in 2014-2015. Experimental design was randomized complete block design (RCBD) as a factorial arrangement with three replications.Nitrogen sources at the four levels (control (no nitrogen source), 150 kg/ha urea (U), 75 kg/ha sulfur-coated urea (SCU), half of Sulfur-coated urea (1/2 SCU) Alkazot Plus biological fertilizer) were first factor, and the second factor were organic fertilizers at 4 levels (control (no organic sources), humic acid, 5 tons/ha vermicompost, half of vermicompost humic acid). The measurement traits were essential oil percent and yield, soil organic matter percent, total nitrogen percent and soil phosphorus and potassium. After ripening the plants harvested at May 2015. The seeds were planted with 4 kg/ha seed density, the 30 cm distance between rows and 5cm far from distance in rows). The Ajowan seeds collected and its essential oil extracted with Clevenger apparatus and water distillation with water vapour methods.
The results showed that the interaction between different sources of nitrogen and organic fertilizers on ajowan essential oil percent and yield was significant at 1%. The highest essential oil percent) 5.5%( and performance )85.4 kg/ha (were obtained at control (without nitrogen source( , vermicompost and urea (U) with vermicompost , respectively. The highest organic matter percentage)1.45%( , soil nitrogen percent) 0.06%( , the percent of soil potash ) 226.3 mg/kg( and soil phosphorus ) 22.38 mg/kg ( were obtained at urea (U) with control (without organic fertilizer) treatments , urea (U) with vermicompost , half of urea -coated Sulfur Alkazot Plus with vermicompost and urea (U) with vermicompost, respectively.
Integrate use of chemical and biological fertilizers, in addition to the positive environmental effects, had positive effects in increasing the characterization essential oil that can be economically effective and also by improving the characteristics of the soil, it could be attain sustainable agriculture )Permaculture(.

In most saline and non-saline soils, nitrogen is the most restrictive nutrient for plant growth. In saline soils, interactive effects of salinity and soil fertility is very important from optimum production. Nutrient imbalance is one of the problems with saline soils. In these circumstances, the fertilizer application may to increase osmotic effect of salt, the question is whether fertilizer is necessary or not, in saline soils? In order to answer these questions, an experiment with factors of salinity and nitrogen were carried out on canola.
In order to evaluate the interaction of salinity and nitrogen, a factorial experiment in a randomized complete block design with factors of salinity and nitrogen were carried out on canola. Salinity treatments were included a non-saline water (0.3 dS m-1), and natural saline waters with salinity of 3, 6, 9 and 12 dS m-1. Nutrient nitrogen levels were four value: zero (N1), 75 (N2), 150 (N3) and 300 (N4) mg N per kg of soil as the ammonium nitrate. The soil texture used in this research was sandy loam containing low amounts of salinity and nitrogen.
The results showed that with increasing salinity, seed canola yield reduced and increased by adding nitrogen to the soil. In this experiment, nitrogen application even to the amount of 300 mg N kg, increased percentage of seed canola oil. The increase was little in the salinity of less than 12 dS m-1. Generally, with increasing water salinity and nitrogen application, nitrogen agronomy efficiency (NAE) decreased for oil production. NAE threshold for oil production in saline conditions depended on the amount of nitrogen application. NAE threshold for oil production in the first level of nitrogen equal to 0.3 dS m-1 and at higher levels of nitrogen increased to 6 dS m-1. By increasing nitrogen levels decreased sharply the percentage of nitrogen apparent recovery (NAR).
With increasing salinity, canola yield reduced and increased by adding nitrogen to the soil. In general, by increasing salinity (especially in high salinity), at all levels of nitrogen, nitrogen physiological efficiency (NPE) of canola increased. In the highest salinity value, N application, increased canola seed oil content so significantly. Nitrogen agronomic efficiency threshold for producing of canola oil in saline conditions depended on the amount of nitrogen application. According to the results, it is recommended to act more cautiously using large amounts of nitrogen in salt condition.

The measurement of wheat crop yield in large areas is time consuming and requires high expenses. One way to save time and cost, using geostatistical methods for mapping crop yield. In this research principle component analysis were used for identifying variables that have correlation with each other, and Kriging and Cokriging were used to map crop yield prediction. Fourty six samples were used for prediction as training, and 21 samples for test. For selection of covariate, principle component analysis were performed. So that predicted yield by square root method in PC2 was selected as covariat in Cokriging. Based on result of cross validation for predicted dataset, RMSE, MAE and MBE for Cokriging was 496, 417 and -91 kg/ha, and for Kriging was 896, 754 and -124 kg/ha. These result showed higher accuracy of yield estimation in Cokriging than Kriging., that also indicated higher accuracy of yield estimation in Cokriging than Kriging.