Soil contamination with heavy metals such as arsenic has harmful effects on human health and agricultural products. Arsenic (AS) is one of the heavy metals which are highly toxic and carcinogenic. This research was conducted to study the effect of organic manure on increasing the Arsenic absorption ability by Cress plant in the greenhouse of the Agriculture and Natural Resources Research Center, Khuzestan, Iran, according factorial experiment based randomized completely design with three replications. Main factor included two levels of organic substance (0 and 10 tons per hectar) and three levels of arsenic concentration (0, 20 and 40 ppm) belonged to sub factor. Mean comparison result revealed increasing arsenic concentration led to increase arsenic accumulation in shoot plant (14.1 ppm), also this trend seems in transfer coefficient trait so cress can be used as a purifier plant to reduce arsenic contamination of the soil. It need to mention by increase arsenic concentration, shoot dry weight decreased (0 ppm arsenic concentration had 20.1 gr per flowerpot but 40 ppm treatments had 0.7 gr). Finally according to contamination symptoms (Necrosis and chlorosis) on cress plant at 40 ppm concentrations and reduced plant shoot dry weight at this concentration, it is recommended to use the cress plant for purification of soil contaminated less than 40 ppm arsenic concentrations. It is noteworthy advised according plant's ability to absorb arsenic and other heavy elements, sowing of this plant as food should be avoided in the contaminated fields. تفاصيل المقالة

Increasing the area of arable oilseed land, particularly rapeseed, and the important roleof potassium in yield and oil content, especially in calcareous and high pH soils, need tomore knowledge about plant nutrition requirement. In this study, the effect of sourcesand different levels of potassium fertilizers on some quality and quantity characteristicson canola yield were assessed by combined analysis factorial experiment based on randomizedcomplete blocks design during 2011-2013. Two potassium fertilizer sources:potassium sulfate and potassium chloride with four levels of the potassium fertilizer control,100, 150, 200 kg.ha-1 in main plot and sub plot, respectively. Results of combinedanalysis of variance showed effect of potassium sources on capsule in plant and oil yieldwas significant at 5% probability level. Also effect of potassium rate on capsule in plant,seed yield and oil content was significant at 5% and 1% probability level. Interactioneffect of treatments on capsule in plant, seed yield, oil yield and oil content wassignificant. Potassium chloride fertilizer impact on yield and its components showedbetter results. Interaction effects of sources and rates of potassium showed the highestseed and oil yield (2128 and 878 kg.ha-1, respectively) from 100 kg.ha-1 potassium chloridetreatment. Also the highest capsule in plant and seed in capsule obtained from 150kg.ha-1 potassium chloride treatment. Finally, for increasing canola yield application of100 kg.ha-1 potassium chloride recommended. تفاصيل المقالة

Canola sensitivity to delayed sowing date should be managed in such a way that the observance of crop rotation with less reduced in seed yield. The research was conducted to evaluate the yield variation of Hyola401 hybrid, affected by sowing date and nitrogen fertilizer treatments. In this study, the effect of planting date and different levels of nitrogen fertilizers on effective characteristics of canola yield were carried out by combined analysis split plot experiment based on randomized complete blocks design in two consecutive years with four replication. Main plot included different planting date (10-Nov, 20-Nov, 1-Dec, 10-Dec.) and four level of nitrogen fertilizers (0, 50, 100, 150, 200 kg.ha-1) belonged to sub plots. The results indicated that canola yield affected by planting date, is subject the linear relationship Y= 2693.0-36.05D (Y= yield and D=planting dates) so crop yield 3.1% decreased per each day delay in planting date. Canola yield in different level of nitrogen treatments was subjected non-liner relation Y=1360.5-0.17N2-0.00063N3 accordingly, most efficiency in the treatment of 100 and 150 kg of nitrogen fertilizer were found. Estimate yield affected by planting date and nitrogen fertilizer based on the relation Y= 1654-36.1D + 10.4N indicated per every day the sowing is delayed about 36.1 kg of seed yield reduction occurs, so to compensate mentioned reduction in the range of studied planting date about 10.4 kg of nitrogen fertilizer should be consumed. Determining the correlation coefficient between yield and its components by using interaction effect of sowing date and nitrogen fertilizer revealed that the number of pods per plants and seed weight had more correlation with the seed yield trait, which is indicated significant effect of the implemented treatments on these two components of yield. تفاصيل المقالة

Soil and water salinity damage and decrease canola yield. However, plant yield should be increased using effective methods. This study aimed at investigating the effect of sulfure application fertilizers on canola yield. To this end, the experiment was conducted in split plot arrangement based on randomized complete blocks design with three replications at Shavoor Research Station in south west of Iran. Main plots was the source of sulfur fertilizer (sulfur element, gypsum, sulfuric acid, golden bio-sulfur) and sub plots were the rate of sulfur application including 6 levels (0, 50, 500, 1000, 1500, 2000 Kg S.ha-1). Results showed sources and rate that of sulfur fertilizers had significant different effects (p<0.01) on canola yield and biologic yield but they had no effect on grain thousand weight and grain in capsule. The highest grain yield and biologic yield obtained from Golden bio sulfur application. The findings also revealed that Interactive effects had significant effects (p<0.01) on canola yield and biologic yield but they had no effects on grain thou-sand weight and grain in capsule. Sulfur fertilizer application is an effective method for compensation damage yield of canola in salinity conditions. تفاصيل المقالة

This research was conducted to evaluate the trend of cadmium accumulation in wheat tissue and cultivated soil affected conventional cropping systems and different growth stage via split plot experiment based on randomized complete block design with three replications during 2014-2015 seasonal year. The main factor included two cropping systems (wheat-rice, fallow-wheat) and growth stage at three level (Tillering, flowering and ripening) belonged to subplots. ANOVA results indicated that the effect of different cropping systems and growth stages on soil and crop cadmium concentration traits was significant at 1% probability level, but interaction effect of treatments was not significant, also soil phosphorus content only affect cropping systems at 5% probability level. Compare effect of cropping systems on cadmium accumulation in cultivated soil and wheat tissue have similar trend (Ascending to descending). In other words the rice-wheat cropping system has more amounts of cadmium (1.71 mg.kg-1 in soil and 1.83 mg.kg-1 in wheat tissue) than to fallow-wheat cropping pattern (1.37 mg.kg-1 in soil and 1.32 mg.kg-1 in wheat tissue). Compare cadmium accumulation between soil and wheat crop tissue revealed an opposite trend. Because of leaching and absorb by plants, trend of soil cadmium accumulation from tillering to ripening stage had down trend. But crop cadmium accumulation due to developed biomass and absorb cadmium had risen trend. Finally management fertilizer consumption of cultivated field according result of soil test and use of phosphate fertilizers by attention to the standards of soil and water research institute led to reduced cadmium accumulation in crop tissue. تفاصيل المقالة

آلوده شدن خاک با فلزات سنگین موجب تجمع این عناصر در بافت‎های گیاهی و کاهش کمّی و کیفی محصولات کشاورزی شده و به این ترتیب سلامت انسان و دام را به خطر می اندازد. بقایای محصول قبلی و میزان مصرف کود‎های شیمیایی مصرفی (خصوصاً کود‎های فسفاته) از مهم ترین عوامل تاثیرگذار بر تجمع کادمیوم در بافت‎های گیاهان می‎باشد. تناوب کشت عامل مهم و تاثیرگذار دیگری بر قابلیت حل شدگی کادمیوم در خاک می باشد. این تحقیق با هدف ارزیابی اثرات سیستم‎های کشت و مراحل مختلف رشد بر غلظت کادمیوم گیاه زراعی گندم بر اساس آزمایش کرت‎های یک بار خرد شده در زمان و در قالب طرح بلوک‎های کامل تصادفی در سه تکرار طی سال زراعی 94-93 در ایستگاه مرکز تحقیقات کشاورزی شاوور (استان خوزستان) اجرا شد. فاکتور اصلی شامل دو سیستم کشت (برنج-گندم، آیش-گندم) و فاکتور فرعی در برگیرنده مراحل رشد (پنجه دهی، گلدهی و رسیدگی) بودند. تفاوت غلظت کادمیوم دانه گندم دو سیستم کشت طبق آزمون T (T-Test) در سطح احتمال یک درصد معنی‎دار شد و غلظت کادمیوم دانه در سیستم کشت برنج-گندم با میانگین 31/0 میلی گرم بر کیلوگرم بیشتر از سیستم کشت آیش-گندم (27/0 میلی گرم بر کیلوگرم) بود که بیشتر از حد استاندارد سازمان بهداشت جهانی است. نتایج تجزیه واریانس نشان داد اثر سیستم‎های کشت و مراحل مختلف رشد و نمو بر صفات غلظت کادمیوم ریشه و ساقه در سطح احتمال یک درصد معنی دار بود. تجمع مقدار کادمیوم ریشه به میزان 09/1 میلی‎گرم بر کیلوگرم و ساقه به میزان 73/0 میلی‎گرم بر کیلـوگرم در سیستم کشت برنج-گندم در مقایسه با سیستم کشت آیش-گندم بیشتر بود. غلظت های کادمیوم تجمع یافته در ساقه یا در ریشه طی مراحل مختلف رشد گندم تفاوت معنی‎داری نداشتند اما در کل از روند افزایشی دارا بودند. به نظر می‎رسد این امر به دلیل عدم تغییر پذیری غلظت کادمیوم در بازه زمانی کاشت تا برداشت گندم است. تفاصيل المقالة