جستجوی مقالات مرتبط با کلیدواژه « شاهی » در نشریات گروه « زراعت »

Nicosulfuron belongs to the group of herbicides that has soil residue and its residue in the soil cause damage to sensitive crops in crop rotation.. In order to study the nicosulfuron herbicide persistence in the soil under biological and chemical degradation of nicosulfuron herbicide in soil, under controlled conditions, an experiment was carried out in a factorial randomized complete block design with three replications during 2015-2016. The first factor included conditions of sterile and non-sterile soil and fertilizer, the second factor included the application of organic and bio-fertilizers at four levels of cow manure, vermicompost, mycorrhiza (2 % w/w) and control treatment without fertilizer, the third factor also included incubating periods at eight levels 0, 4, 8, 16, 35, 50, 80, 100 days. The results showed that nicosulfuron degradation was chemical hydrolysis under sterile conditions, and was biodegradation and chemical hydrolysis under non sterile conditions. Nicosulfuron degradation rate was not significant difference in control treatment (without organic fertilizers application) under conditions of sterile, non-sterile fertilizer and soil, But increased with application of organic and bio-fertilizers and deacresed residue herbiced. The lowest residue rate was obtained from the application of cow manure under non-sterile (0.01 mg/kg/ day) and sterile 0.03 mg/kg/ day) conditions. The highest and the lowest degradation rate were obtained from the application of cow manure under non-sterile conditions and control treatment under sterile conditions. Also the lowest and the highest half-life was obtained by 15.33 and 38.5 day from the application of cow manure under non-sterile conditions respectively.

Abstract   Background and Objectives Khuzestan Province is one of the most important areas that provide vegetables throughout winter and spring in Iran. The vegetables are mainly picked up in the afternoon, so it cannot be supplied to the market. In this time of the day, the minimum amount of nitrate is accumulated in leafy vegetables, with a gradual increase throughout the night. On the other hand, its highest level is in the early hours in the morning. The purpose of this study is to evaluate nitrate and nitrite accumulation in vegetables produced in different areas of Ahwaz during winter and spring.   Materials and Methods This experiment was conducted in a randomized complete block design arranged in a split-split-plot design with three replications in the Department of Horticulture, College of Agriculture, Shahid Chamran University of Ahvaz. In the treatments viz. first to third harvest dates (1): February 6, 2016, (2):March 4, 2016 and (3): April 7, 2016 respectively were the main factors and nine vegetable species (including coriander, parsley, mint, fenugreek, chard, spinach, leeks, dill and watercress) kept in sub plot, three vegetable production areas in Ahvaz were arranged in sub plot in sub plots and three fields were selected in each of these areas. Before and after cultivation, all planting, harvesting and harvesting operations were carried out on the same field in the selected fields. The concentration of nitrate was measured by the method introduced by Cataldo et al. (1975) and the nitrite concentation was measured via the method of Abu-Dayeh (2009). The data were analyzed using SAS software and the mean comparison was calculated using Duncan's multiple range tests at a probability level of 5%.   Results Nitrate and nitrite contents of the produced vegetables were different depending on various regions, harvesting time and vegetable species. The highest nitrate content was observed in parsley fromthe first harvest in the southern region of Ahwaz (4.4 mg/kg-1 dry matter) and the lowest amount of nitrate was recorded in watercress from the third harvest in the northern region of Ahvaz (1.4 mg/kg-1 dry matter). Also, the highest nitrite content was observed at the first harvest in the westhern region of Ahwaz in mint and the lowest amount of nitrate was recorded in the second harvest in the northern region of Ahvaz in chard. In winter, the environmental conditions in Ahwaz are suitable for the growth and development of leafy vegetables (Boroujerdnia et al., 2007); however, soil conditions provide manganese uptake by plants. Moreover, high light intensity is another factor which can decrease nitrate in leafy vegetables. The number of cloudy days in Ahwaz is very low; therefore, the number of sunny days with high radiation intensity is high in winter. This phenomenon greatly reduces the content of nitrate in leafy vegetables.   Discussion The amounts of nitrate and nitrite content in various species of vegetables produced in three regions of Ahvaz during the cold season were much lower than the standard figures. Therefore, we can conclude that the quality of vegetables produced in Ahvaz is very high in terms of nitrite and nitrate contents.

In the present study, the effects of lead and putrescine on Lepidium sativum plant were examined. A factorial experiment was conducted in a completely randomized design with four replications. Lead nitrate at concentrations of 0, 125, 250 and 1000 micro molar and putresine at 0 and 1 mM was used. Lead and putresine increased plant fresh weights compared to lead treatment of same concentration and at a concentration of 500 micromolar fresh weight was10 gr. There was no significant difference between dry weights of treated plants and control. Lead treatment increased polyphenol oxidase (0/8 micromoles per minute per gram fresh weight in 1000 micromolar) and catalase (0/053 micromoles per minute per gram fresh weight in 1000 micromolar) activities. The use of putrescine and lead increased the polyphenol oxidase enzyme activity (0/99 micromoles per minute per gram fresh weight in 125 micromolar) compared to lead treatment of same concentration. The combined use of putresine and lead reduced the amount of proline except at 250 micromolar of lead compared to plants treated in the same concentration of lead. Treatments of lead at concentrations of 125, 250 and 500 micromolar and putrescine, were reduced the percent of inhibition compared to the treatment of lead in the same concentration. Inhibitory percentage was increased on 1000 micromolar of lead. The total phenols were not significant difference under the lead and putrescine treatments. In Lepidium sativum under lead stress activated polyphenol oxidase, Proline increasese. Useing putrescine has controlled production of proline by reduction the stress effects

Salinity is one of the major environmental stresses, which has deleterious effect on growth, development and yield of crops. Due to the gradual increase in soil and water salinity in the East Azarbaijan province of Iran, the garden cress cultivation in this region has always been associated with many problems. In order to evaluate the tolerance of this plant to different levels of salinity through some physiological characteristics, the present experiment was conducted using randomized complete block design with five treatments consisting of 0, 50, 100, 150 and 200 mM NaCl concentrations and three replications. The results showed that with enhancement in salinity levels, sodium, proline, soluble sugars and carotenoids content increased but potassium content, potassium to sodium ratio and amounts of chlorophyll a and b declined. Salinity had no significant effect on chlorophyll a+b content, chlorophyll a/b ratio and relative water content. Plants were destroyed at 200 mM concentration after 21 days. Since potassium to sodium ratio was lower than 1 at 100 and 150 mM concentrations, continuing of salinity would has presumably led to the destruction of plants in these treatments