محمدجواد مصطفوی

Intercropping of basil with legumes due to morphological differences and more importantly, their biological stabilization can be a step towards sustainability in agriculture and also to avoid the use of chemical inputs and therefore produce healthier products. Therefore, the objectives of this experiment were to evaluate and compare different indicators of growth, yield and ecological and economic usefulness of basil with green bean in pure crops and mixed replacement ratios in Mashhad climatic conditions.

An experiment was conducted in RCBD design at the research farm of Ferdowsi University of Mashhad in the growing year 2018 19. The treatments were: 1) sole cropping of green bean (P), 2) and also basil (O) and different ratios of intercropping of these two plants, including 3) 1:3 ratio of green bean and basil (P1O3), 4) ratio 2:2 green bean and basil (P2O2) and 5) 3:1 ratio green bean and basil (P3O1). Daily values of growth indices during the growth period of plants were estimated using the specific functions, and at the end of the growing season, the final yield of intercropped species (fresh green pods of green bean and basil dried seeds) was measured and indicators related to the advantage of intercropping including land equivalent ratio (LER), actual yield loss (AYL) and the monetary advantage index (MAI) were calculated. Function fitting, statistical analysis of data and drawing of figures were performed using Slide Write ver2.0, SAS v 9.2 and MS Excel 2016, respectively.

The highest LAI recorded in sole cropping of green bean and basil (3.4 and 3 respectively) and the lowest was for green bean in P1O3 (0.2) and for basil in P3O1 (2). Also, highest TDM in sole cropping of green bean was 973 g m2 and in sole cropping of basil was 1654 g m2 and the lowest ones for intercropped green bean was in P1O3 (44 g m2) and in the intercropped basil in P3O1 (755 g m2). The highest CGR of green bean and basil in their sole cropping were 20.56 and 17.92 g m2 day-1, respectively. The mean RGR of green bean was 0.03 g g-1 in P1O3 and the highest RGR was in basil in the sole cropping treatment (0.03 g g-1) The highest NAR in green bean was in its sole cropping (8.3 g m2 day-1) and basil (8.5 g m2 day-1). No economic yield was achieved for green bean in P1O3 and P2O2 treatments, so all the advantage indices of intercropping including LER, AYL and MAI in these treatments were negative. Also, the highest yield of basil was obtained in P1O3, which was not significantly different from its sole culture, and only in this treatment the intercropping advantage indices studied were positive and preferred to sole culture.

The results truly showed incompatibility of basil with green bean in intercropping due to low competitiveness and weakness of green bean in intercropping with basil. Although intercropping in P3O1 treatment was economically and ecologically beneficial, but by considering all the conditions such as the possibility of implementing this cultivation ratio, it is suggested that while examining more different aspects of intercropping of basil with green bean such as weed competition and mechanisms of basil competition with green bean, another legume crop that has more desirable characteristics in terms of ecological compatibility and non-interference of ecological niches with this plant to replace green bean in basil production systems.

Carbon footprint (CF) is the total amount of greenhouse gas emissions per unit of farmlands. Since the used inputs have an important role in greenhouse gas emissions, CF as an ecological indicator have been extensively applied for assessing the environmental externalities in agroecosystems. This study was conducted to estimate the CF and carbon efficiency (CE) of saffron production systems in North Khorasan, Razavi Khorasan and South Khorasan provinces. Also, life cycle assessment analysis is calculated for quantifying the impact of saffron farming activity on the environment. Studied indices were global warming potential (GWP), acidification potential )AP) and eutrophication potential in terrestrial (UPT) and aquatic (UPA) sub-categories, N2Odirect, N2Oindirect, N2O emissions affected as volatilization and leaching, carbon inputs (Ci), carbon outputs (Co), CF and CE. The results revealed that the lowest GWP for saffron production systems was related to south Khorasan with 339.43 kg CO2 equiv./ one kg flower yield. The minimum environmental index (EcoX) was recorded for south Khorasan (0.039 EcoX/ one kg flower yield). N2O emissions in South Khorasan, Razavi Khorasan and North Khorasan provinces were estimated with 95974.51, 199674.4 and 344723 kg N2O per one ha, respectively. The largest N2O emissions affected as leaching and volatilization were calculated for North Khorasan province (with 1.21 and 24.23 kg N2O per one ha, respectively). The maximum Ci and Co were related to North Khorasan province with 117986.52 and 15135.56 kg C per one ha, respectively. The largest CF and CE were computed for North Khorasan and south Khorasan provinces with 7.8 and 0.18, respectively. It concluded that adoption on conservation and reduced tillages, N2- fixing pulses, cover crops and green manures in rotations with saffron and increased nitrogen use efficiency as ecological approaches can optimize the system performance while reducing environmental externalities and the carbon footprint of the crop cultivation. So, with relevant agro-environmental policies in saffron production systems along with the adoption of improved agronomical practices increasing flower yield with no cost the environment can be achieved effectively, efficiently and economically.

Climate change is an undeniable fact, and today this phenomenon has become a global issue. Its effects on crops yield and their stability facing increasing global climate change. Yield stability will be the most serious challenge for maintaining agricultural production and food security. After the cereals, pulses are the second most important source of food in Iran and the world, have great importance in agricultural systems and human nutrition. The yield of pulses has more variation than other crops, so the study of the yield stability of these crops can help the policy makers to develop the plans helping preservation and enhancement of pulses yield. The aim of this study was to research the yield stability of pulse crops in Iran for 33 years using different analytical methods.

All available statistics including the yield data on of chickpea, beans, and lentil data for the years 1983 to 2016, were collected from the published statistics by the Iranian ministry of agriculture. The residuals of regression between yield and time of the yields and its trends calculated from linear, bi-lines and tri‑lines models which were selected based on the higher coefficient of determination (R2) and normality of the residuals. Absolute values of the regression residuals were also used to calculate relative residuals of yields. The coefficient of variation (CV) for yields of every 4-year period was calculated by dividing the standard deviation by average. Mean yield of all pulses also were calculated as “Environment Index” to use in Finley-Wilkinson model. The positive slope of the residuals of linear regression, CV and Finlay‑Wilkinson model means the increase of yield instability and slope of zero and the negative slope of the linear regression indicates relative stability and increase of stability of the yield, respectively.

The increase in rainfed chickpea yield over the studied period was low and close to 0.75 kg ha‑1 y‑1. The trend of rainfed lentil yield was negative with a slope of -0.61 kg ha-1 y‑1 and the highest amount of yield increasement belonged to rainfed and irrigated bean by 25.17 and 21 kg ha‑1 y‑1. All the trends of residuals of pulses were positive that means instability of pulses yields over the studied period. Irrigated chickpea and rainfed lentil showed the highest CV trends and rainfed bean have had the highest range of values of CV. A CV as a simple and widely used parameter can show the standard deviation of the yield over the different environments and years, so higher values and positive trend of CV means higher fluctuations of yield level and its lower stability. Yield stability of the rainfed bean was lower than others but the trend of yield stability of irrigated chickpea and rainfed lentil is more than other pulses. Based on Finley-Wilkinson model, the trend of stability of all pulses was low and negative. Yield stability of the irrigated and rainfed bean was the lowest. Although due to the fact that rainfall is the major factor affecting the rainfed yield, it is expected that the irrigated yields to be more stable than rainfed yields, in contrary to our expectations, based on the results and the slope of the regression of the model, the yield of irrigated chickpea and lentil were more unstable than rainfed yield. The cultivated area of rainfed chickpea and lentil and irrigated beans showed a positive trend during the study period and inversely, the cultivated area of irrigated chickpea and lentil and rainfed bean were decreased. Absolute residuals of the yield as the indicator of stability (which has an inverse relationship) as a function of cultivated area, increased in about all of the studied crops except irrigated chickpea and rainfed bean. Most stable crops in the larger cultivated area were irrigated chickpea and rainfed bean.

According to the results, the overall trends in the yield increasement of pulse crops in Iran are low. The trend of chickpea and lentil has been much lower than rainfed and irrigated bean. On the other hand, fluctuations in yield over the past decades are high and therefore the stability of the country's pulses is also low. In Iran, it seems essential to development of new integrated and effective policies for the supporting scientific researched in the order to introducing new varieties, reduction of yield gap of pulses crops and improvement of their yield stability, and also education in order to improve the management of the pulse crops agroecosystems, as well as mitigation of the effects of climate change.

It has been predicted that the population of the world will reach up to 9 billion people until middle of current century so to meet the demands for food, it is necessary to supply more by developing sustainable agriculture and ecological intensification of food production to avoid disadvantages of conventional agriculture. Intercropping is one of the sustainable agriculture strategies that has been proven that causes more use of available resources by intercropped species. It is one of the key strategies of sustainable agriculture because of its efficiency in using of the resources like nitrogen, light and water and improving vulnerability of crops against diseases and pests. Pulses are very valuable for agroecosystems and human health, because of many advantages like high protein content and nutritional values and symbiotic fixation of nitrogen. So, an experiment was conducted in order to study of yield characteristics of black-eyed pea (BEP), the pinto bean (PB), kidney bean (KB) and green bean (GB) as bean ecotypes affected by intercropping with cucumber and partial land equivalent ratio (LER) of the beans.

The experiment was held during growing season 2015-16 in the experimental field of Ferdowsi University of Mashhad based on a randomized complete block design (RCBD) with six and eight treatments (for different studied indices) and three replications. Treatments included sole culture of BEP, PB, KB and GB and their 1:1 ratio in replacement intercropping with cucumber. The plots had five 120-cm sized width and 6×3 meter dimensions. The gaps between the plots and the blocks were one and two meters, respectively. The studied indices included the number of sub-branches per plant, stem length, number and weight of seeds per pod, numbers and weights of pods and seeds per plant, shrub and plant [dry] weights, 100-seed weight, biological and economic yields and harvest index for seeds of grain bean ecotypes (including BEP, PB and KB), and for GB, studied indices included the number of seeds per plant, 100-seed weight and economic yield (total weight of harvested green pods per ha). Partial LER of the studied plants was calculated and finally statistical analysis of data and drawing the figures done using SAS v.9.2 and MS Excel 2016 respectively. Duncan’s multiple range test (DMRT) also used for comparing the means at probability level of %5.

The results showed that except the number of sub-branches per plant, there were significant differences between the treatments for all other studied indices. The highest stem length was recorded in sole culture of BEP that was significantly different compared with other treatments but there was no significant difference between sole culture and intercropping treatments of PB and KB. Competition for interception of light may cause this result for BEP. Number and weight of seeds per pod and numbers and weights of pods and seeds per plant were higher in intercropping treatments of the plants in comparison of their sole culture. Many other studies like results of Noorbakhsh et al, (2015) and Khalaf (2016) support our findings. 100-seed weight was different between the plants but no significant difference was observed between intercropping and sole culture of each plant. It seems that 100-seed weight is a genetic property that not be affected by intercropping. The biological and economic yield of the bean ecotypes were significantly higher in their sole culture compared with their intercropping due to lower plant density in intercropping but by considering the results of partial LER calculation, it concludes that intercropping was more useful for all studied plants. The highest value of partial LER (0.69) was calculated in GB and the lowest one was recorded to KB. The economic part of GB was its green pods, so its partial LER was higher than another studied plants in comparison of other plants that their seeds form their economic yield. Similar to 100-seed weight, the harvest index was statistically different between the bean ecotypes but it was similar between sole culture and intercropping treatments of each plant because of parallel trends of variations of biological and economic yields of the plants.

Based on the results, intercropping of BEP, PB, KB and GB with cucumber is benefit for ecological intensification of production of the studied pulses. So, it can be suggested as an efficient strategy for sustainable development of food production.

Response surface methodology (RSM) is defined as statistical technique for optimization of multiple parameters which determine optimum process conditions by combining experimental treatments (5,10,11). In this work, optimization of N and P fertilizers on yield, yield components and seed quality of wheat using RSM were studied.

An experiment was conducted with 13 treatments and two replications at the Research Field of Ferdowsi University of Mashhad during the growing season of 2015-2016. The treatments were allocated based on low and high levels of N fertilizer (0 and 400 kg Urea per ha, respectively) and P fertilizer (0 and 100 kg triple super phosphate per ha, respectively). Biological yield, seed yield, harvest index, growth criteria and yield components (such as tiller No./m2, plant height, spike length, seed No./ spike, seed weight/ spike, seed weight/ plant, spike No./ plant, spike weight/ plant and dry weight of stem per m2) and seed quality characteristics (including N percentage, protein percentage and P percentage) were calculated as dependent variables and changes of these variables were evaluated by a regression model. Lack-of-fit test was used to evaluate the quality of the fitted model. The adequacy of the model was tested by analysis of variance. The quality of the fitted model was judged using the determination coefficient (R2). Finally, the optimum levels of N and P fertilizers were calculated based on three scenarios including economic, ecological and economic-ecological.

The results showed that effect of linear component was significant on harvest index, spike length, yield components (such as seed weight per plant, spike No./plant, spike weight per plant and tiller No./m2), N percent and protein percent of seed. Effect of square component was significant on biological yield, seed yield, tiller No./m2, seed weight per plant and spike weight per plant, N percent, protein percent and P percent of seed. Interaction effect of full quadratic was significant on plant height, spike length and seed No./spike and N percent of seed. Lack of fit test had no significant effect on the studied traits. The full square model for the response variables gave insignificant lack-of-fit indicating that the data of experimental were satisfactorily explained. The highest observed and predicted values of seed yield were recorded for 400 kg Urea per ha+100 kg triple super phosphate per ha and 200 kg Urea per ha+50 kg triple super phosphate per ha with 717.54 and 594.89 kg.ha-1, respectively. The maximum observed and predicted amounts of seed N percent (with 1.72 and 1.62 percent, respectively) and seed protein percentage (with 10.76 and 10.02percent, respectively) were recorded for 400 kg Urea per ha+50 kg triple super phosphate per ha. Both seed yield and N and P percent of seed were considered in economic-ecological scenario, so the estimated levels for N and P fertilizers were 141.41 kg Urea.ha-1 and without P fertilizer.

Increasing rates of N and P fertilizers up to optimum rates increased yield and seed quality of wheat. Nutrient optimization enhances nutrient absorption and yield in the wheat cropping systems may reduce the dependence on external sources of chemical fertilizers that increase the costs of production and can potentially contribute to environmental contamination. The optimization of soil nutrients provides information on the sustainability of cropping systems and potential environmental pollutions. Generally, nutrient optimization is a useful technique widely used in modern agriculture.

In order to evolution of radiation use efficiency (RUE) of sesame in the condition of using biological and chemical fertilizers and calculation of light extinction coefficient (K), an experiment was conducted in the year 2013 in RCBD design with 3 replications and 10 treatments. Treatments included biological fertilizers of Nitroxin, Biophosphor, Biosulfur, the mixture of Nitroxin-Biophosphor (Ni+BP), the mixture of Nitroxin-Biophosphor-Biosulfur (Ni+BP+TB) and chemical fertilizers of Urea, Triple superphosphate, the mixture of Urea-Triple superphosphate (U+P), the mixture of Urea-Triple super phosphate-Sulfur (U+P+S) and Control. Results showed that light extinction coefficient of 0.7 was an acceptable value. Biological and chemical fertilizers increased leaf area index (LAI) and RUE of Sesame and generally, chemical fertilizers increased RUE more in comparison of biological fertilizers. The highest value of LAI (3.42 and 3.32) belonged to U+P+S and U+P. RUE values in mixture treatments of biological and chemical fertilizers especially for Ni+BP+TB and U+P+S (1.34 and 1.41 respectively) were greater than its values in the sole application of fertilizers. Urea increased radiation use efficiency of sesame (1.34) more than Nitroxin (1.14), while the amount of increase of radiation use efficiency in triple superphosphate (1.26) and Biophosphor (1.25) was almost identical. Therefore, it is recommended that fertilization of sesame be done by using the mixture of some different biological or chemical fertilizers in order to maximizing RUE by compliment of plant nutritional needs.

In order to study the correlation between yield component and seed yield of sesame and to determine the relationships between shoot length, capsules per plant, seeds per capsule, 1000-seed weight, biological yield and harvest index, in 2013 an experiment was conducted based on RCBD design with ten treatments (including different biological and chemical fertilizers) in experimental field of Ferdowsi university of Mashhad. Results showed that there was a positive and significant correlation between seed yield and plant height, but much of the efficacy of plant height on seed yield was by influencing capsules per plant. Biological and seed yield had a positive and significant correlation (0.81 and 0.87, respectively) with capsules per plant. The highest direct effect of components on seed yield was belonged to “capsules per plant” and the least belonged to “plant height”. Analysis of regression showed that capsules per plant and biological yield had the most effect on seed yield and their partial regression coefficient was 10.7 and 0.134, respectively. The partial regression coefficient for standardized data of these two traits showed the priority of biological yield in comparison with capsules per plant. Yield function that is a function of capsules per plant and biological yield, with the coefficient of determination of 0.96 justified a large part of seed yield. So biological yield and capsules per plant were the most important traits of sesame that can be considered by researchers. Also, after calibration of yield function, it can be used for estimating the production of sesame.

Despite the positive and inevitable functions of organic farming, this agricultural system still has little desire to accept it by farmers and producers. This study aiming to analyzing the effective factors on the Acceptance of organic farming by farmers in rural areas of the Bala-darband district of central Kermanshah province in Survey research method (2016-2017). In addition to documentary overview, a questionnaire was used in the survey as its validity confirmed by a panel of experts and its reliability was estimated through a guide study outside the statistical sample with Ordinal alpha coefficients (0/75-0/93), Composite Reliability (0/75-0/92) and Average Variance Extracted (0/55-0/67) was confirmed. for this purpose, Smart PLSver3 software was applied. The statistical population of were rural farmers of Bala-Darband (N = 2157) which 180 of them were selected by multistage cluster sampling method as sample group. Both SPSSver20 and AMOSver20 softwares were applied to analyze the collected data from the field. Finally, based on the direct and indirect effects of the developed structural model, The result showed that tangible behavioral control had the most effect on adoption of organic agriculture. Also, factors such as decision on use structures of adoption, Attitude, Knowledge and Cognizance, Subjective Norm and Perceived Usefulness towards organic farming seen as the most effective factors on the structure of organic farming acceptance in order. The results of this research can help managers and policy makers to seek strategies towards better adoption of organic farming among farmers.

IntroductionNowadays technological innovations, the use of chemical inputs, development of methods and etc., help agriculture to produce food for human. However, some problems such as growth in fertilizer prices and environmental pollution has drawn attentions to sustainable agriculture.
Sesame as the oldest known oil-seeded plant by mankind has ranked #9 among 30 important oil seeds. Therefore cultivation of this valuable plant should be done based on ecological principles and inputs.
Growth and phenological aspects of sesame affecting by bio-fertilizers is less known. Therefore, the aim of this experiment was to evaluate the growth and phenology of sesame by application of various biological and chemical nutritional sources.
Materials and MethodsThis experiment was conducted in randomized complete block design (RCBD) with 3 replications and 10 treatments including Nitroxin® (Ni), Biophosphor® (BP), Biosulfur® (BS; with recommended amount of elemental sulfur), double mixture of Ni, triple mixture of Niӿ, Urea (U), triple super phosphate (P), double mixture of U, triple mixture of U plus the used amount sulfur in BS, and control.
Sampling was conducted every 7 days and growth indexes including, leaf area index (LAI), total dry matter (TDM), crop growth rate (CGR), relative growth rate (RGR), net assimilation rate (NAR) were studied during growth life of the crop. Phenological stages were recorded then GDD was calculated for different phenological stages. Statistical analysis and drawing of figures were performed using Minitab and MS Excel.
Results and DiscussionA. Growth Indexes: Changes in LAI, TDM, CGR, RGR, and RGR under all treatments were almost similar. during the early days of growing, LAI increased gradually and then it rose sharply after production of more leaves by the plant in most of the treatment about 35 days after sowing. After the flowering stage, by lowering of increase in LAI, all of the treatments reached to their maximum LAI and then decreased. Control and BS had minimum LAI (2.42 and 2.54) among all treatments. LAI of U㿤 and U were highest LAI (3.42 and 3.32 respectively) and after it, Niӿ (3.03) and Ni (3.01), urea (2.98), Nitroxin (2.85), Biophosphor (2.75), triple superphosphate (2.78) were placed respectively.
The highest dry matter accumulation occurred in plots that meet higher LAI, resulting in a higher potential for the production and accumulation of dry matter. So, the highest dry matter accumulation was recorded in U㿤 and U, and then Niӿ and Ni and urea.
Due to the development of leaves and roots, CGR increased and then reached to its highest amount after 52 to 70 days from the sowing. Then, about 100 days from sowing, CGR decreased and this trend continued to the end of plant life. Application of Nitroxin and Biophosphor increased CGR of sesame, but it did not affect CGR of Biosulfur treatment. The double and triple mixture of biofertilizers and chemical fertilizers increased the growth of sesame in comparison to their sole application.
Numeral amount of RGR was between 0 to 1 that describes the amount of increase in plant dry matter weight in order to its previous dry matter’s weight among a time period.
In all treatments, NAR at the beginning of the growing season due to low levels of leaves and photosynthesis were low. Gradually in the middle of the growing season, NAR increased, along with the increased growth of plants and their LAI. Because of some reason remobilization and aging of the leaves and reduction of the efficiency of photosynthesis, NAR has an intense reduction. All the treatments had higher NAR comparing to control.
B. Phenological Stages: Statistical analysis of data showed that the effect of treatments on phenological stages was not significant. But seeds in the treatments of biofertilizers grew 3 days earlier in average. It has been proven that farm managerial decisions that cause faster growing of plants (even one day), can be effective in competitions of crops versus the weeds.
ConclusionsBased on the results, it can be concluded that although nutrition resources affected the sesame growth indexes, they had no effect on phenological stages of sesame.

Sesame is a valuable oil seed crop that has lower yield and input response in comparison to other crops. Because of the less Improved genetic characteristics of sesame in comparison with dominant crops¡ and the lack of development in management methods and mechanization in sesame have resulted in neglecting cultivation of this plant (Rezvani Moghaddam et al¡ 2005; Jahan et al.¡ 2012). Several studies have presented useful effects of biological fertilizers on crop yield that¡ in addition to providing necessary nutrients for plants¡ they have lower cost and unlike chemical fertilizers do not have adverse effects on the environment. These fertilizers could therefore be helpful in the cultivation of crops such as sesame and restoring them to agricultural systems (Jahan and Nassiri Mahallati¡ 2012). The aim of this study was to investigate the effect of biological and chemical fertilizers supplying nitrogen¡ phosphorus and sulfur for the production of sesame.
An experiment was conducted based on a RCBD with three replications at the agricultural research field of Ferdowsi University of Mashhad during the 2012-2013 growing season. Ten treatments that included Nitroxin (1)¡ Biophosphor (2)¡ Biosulfur (3)¡ a double mixture of 1 and 2 (4)¡ a triple mixture of 1 and 2 and 3 (5) and chemical fertilizers of Urea (6)¡ triple super phosphate (7)¡ double mixture of 6 and 7 (8)¡ triple mixture of 6 and 7 and elemental sulfur (9) and a control (10) were applied. For all treatments¡ 20 ton ha-1 of manure was applied before planting.
The results showed that application of biological and chemical fertilizers was significant on the number of capsules per plant¡ biological yield¡ grain yield and oil yield. The number of capsules per plant was the most important component in sesame yield (r=0.87)¡ but the number of seeds per capsule¡ 1000-seed weight and harvest index were not affected by treatments. Also¡ seed oil content was not affected by the treatments¡ so the highest oil yields were gained in treatments which had produced more seeds. In treatment no.9 (multiple mixture of chemical ferilizers of urea-triple super phosphate-elemental sulfur) the biological and grain yield increased by 51.1 and 54.44 percent¡ respectively¡ in comparison to the control. Generally¡ the treatment of a multiple mixture of chemical fertilizers of urea-triple superphosphate-elemental sulfur had the highest number of capsules per plant (107 capsules)¡ biological yield (20¡908 kg ha-1)¡ grain yield (3¡757.8 kg ha-1) and oil yield (1¡674.6 kg ha-1)¡ which had no significant difference with the treatment of multiple mixture of biological fertilizer of Nitroxin-Biophosphor-Biosulfur (treatment no.5). In this experiment¡ although biological fertilizers did not affect the sesame seed oil percentage (a qualitative feature) because of such reasons as plant characteristics or ineffectiveness of effective microorganisms of biological fertilizers¡ they increased the quality of the product (oil yield) in parallel with yield.
The results showed that¡ in general¡ the use of biological fertilizers can increase both growth and yield characteristics of sesame seeds similar to chemical fertilizers. The highest yield of sesame was gained in mixed treatments of biological and chemical fertilizers. The application of these fertilizers increased leaf area index and improved the ability of plants to grow better and produce more biomass¡ thereby achieving a higher yield. In general¡ it can be said that for successful and economic production of sesame¡ in addition to chemical fertilizers bio-fertilizers can also be used. In addition¡ this offers long-term benefits such as reducing the input costs¡ greater sustainability of production and agricultural production and environmental health.

In order to evaluate the allelopathic effects of white top (Cardaria draba (L.) Desv.) water extracts on corn and canola germination characteristics، an experiment was carried out based on CRD design with three replications in agronomy research lab of Yasouj University. Treatments were included of 25%، 50%، 75% and 100% water extract (50 gr dm/L) of root، leaf and stem، inflorescence and whole plant of whitetop and control (distilled water) were applied. Results showed that germination percent and rate، radicle and shoot length and dry weight، and root/shoot length ratio and dry weight were decreased significantly by increasing extract concentration. Effect of shoot extract was greater than of root. Inhibition percent was increased by extract concentration، but there was not significant differences between 75% and 100% extract concentration. Based on the results، canola was more susceptible than maize to allelopathic effect of whitetop extract. Finally based on the results it is possibleto say that whitetop can prevent the germination and growth of canola and sweet corn by producing the allelopathic compounds، and decreasing green surface and undesirable growth of crops.