Caspian Journal of Environmental Sciences
Volume:4 Issue: 1, Winter 2006

Cadmium (Cd) is among the most widespread and toxic heavy metal in several part of the world. Its toxicity in soil is becoming a severe threat to living organism worldwide. It is one of the main pollutants in paddy fields near industrial areas and highly toxic to plant growth and development of the plants. Cd can be easily taken up by plants and enter the food chain. Therefore, precautionary measurements should be done to reduce accumulation of Cd in crops to alleviate the risk of health hazards in response to Cd-polluted soils. Several strategies have been proposed for the successful management of the Cd-contaminated in crops. One approach, applicable on slightly contaminated soils, is selection of plant genotypes with high ability to repress root uptake and shoot transport of Cd which could be a reasonable approach to alleviate adverse effects of Cd toxicity in crops. Moreover, the toxic effect of Cd can be decreased by proper application of essential nutrients such as Zn, S and N fertilizers Cd contaminated soil.

Poaceous weeds are prolific and competitive in winter crops، but they are more insidious in wheat due to their similar morphology and growing requirements. Herbicides are effective and efficient tools of weed management، however، they are vulnerable to resistance، and herbicides with different modes of action might check the dominance of a particular weed flora. The current study was undertaken to see the response of three poaceous weeds viz. ، Phalaris minor، Avena fatua and Lolium temulentum، to herbicides Isoproturon، Topik (Clodinafop-p) and Puma Super (Fenoxaprop-p). Completely randomized design with two factor treatments (weeds، herbicides) and eight replications was employed. Data were recorded on chlorotic and necrotic effects of herbicides on weeds، and percent mortality at the time interval of 14، 21 and 28 days after the application of herbicides. Dry biomass weight of weeds was recorded at 30 days after the treatments. Results indicated that all the parameters were affected significantly over the period of time. Maximum counts of chlorotic (2. 16) and necrotic (2. 97) weeds were observed at the 21st day of treatment. The highest mortality (31. 1 %) was recorded at 21st day after the application of herbicides. Phalaris minor was the most resistant weed to herbicides showing the lowest mortality (only 17. 7 %) compared to other two weeds. Maximum dry weight of weeds was recorded in control while a minimum of 0. 456 g dry weight was observed where Topik (Clodinafop-p) was applied. For the effective control of P. minor، A. fatua and L. temulentum weeds in wheat crop، Topik (15 WP) @ 0. 37 kg a. i. ha-1 was proved to be the most suitable herbicide applied at 3-4 foliar stage.

Oral supplementation with potassium bromide (10, 20 and 40 ?g/ml) to fifth instar larvae of CSR2, CSR4 and CSR2xCSR4 crossbreed races of the silkworm, Bombyx mori resulted in a significant increase in the fat body glycogen in all the treated groups and in all the three races of the silkworm, B. mori. The fat body protein content was increased with 20 and 40 ?g/ml treated groups in CSR2 and CSR4 races and in all the treated groups in CSR2xCSR4 cdrossbreed race of the silkworm, B. mori. However, there was a decrease in fat body protein with 10 ?g/ml treated groups in CSR2 and CSR4 races. There was a significant increase in the haemolymph trehalose with 10 ?g/ml in CSR2 race, in all the treated groups in CSR4 race and with 20 and 40 ?g/ml treated groups in CSR2xCSR4 crossbreed race when compared over the respective carrier controls. There was also a significant increase in the haemolymph protein treated with 20 and 40 ?g/ml in CSR2 race, with 10 and 20 ?g/ml in CSR4 race and in all the treated groups in CSR2xCSR4 crossbreed race when compared over the respective carrier controls. There was a significant increase in the fat body total lipids with all the treated groups and in all the three races of the silkworm, but there was a significant decrease with 40 ?g/ml treated group in CSR2xCSR4 race of the silkworm, B. mori when compared over the respective carrier controls. These results indicated that the biochemical contents of the fat body and haemolymph to potassium bromide showed good response in all the three races of the silkworm, Bombyx mori L

The influence of moisture content of mulberry leaf on the growth، development and moisture build up in the body of silkworm was studied by feeding with different maturity leaves to late age of silkworm larvae. Significantly higher larval moisture (79. 78%) ، larval weight (65. 65 g) ، pupal moisture (73. 81%) was recorded in top tender leaf (high moisture) fed batches and least was recorded in the coarse leaf (lower moisture) fed batches. Significantly positive correlation between moisture content of leaf and larva to different variables like growth rate، larval weight، single cocoon weight، single shell weight and average filament length were recorded.

In mulberry orchards in northern part of Iran, thrips is a dominant pest and causing a lot of damage to the mulberry. The effect of pest on bio-chemical parameters of mulberry leaf of two varieties viz. Kenmochi and Ichenoise and also the effect of feeding of infested leaves on rearing performances have been studied. For the study, six plots of 200 m2 area of both the varieties were selected and three of them, of each variety, were sprayed with 0.5% Metasystox at a peak period of occurrence of nymph population to obtain the good healthy leaf without thrips infestation. Another 3 plots were left without pesticide spray to obtain infested leaves so as effect of infestation on chemical parameters of leaf and effect of infested leaves on rearing performance could be studied. During rearing, larvae were fed with good quality of mulberry leaf while another lot were fed with infested leaves. The results showed that there was a decrease in nitrogen, phosphorus, potassium and protein contents of leaves by 2.5, 10.8, 18.7 and 12.5%, respectively due to infestation and the decrease in these parameters was more in Kenmochi. There was also a significant decrease in total cocoon production, cocoon weight, pupal weight, and shell weight due to feeding of infested leaves. However, there was no significant difference in shell ratio between the lots fed with healthy and infested leaves.

Cotton fibres were subjected to cleaning process and then characterized for maturity. Decrystallisation and swelling processes with caustic soda، ethanol، propan-2-ol and Trichloroethene on the native fibres were carried out. The effects of these on the strength and moisture regain were investigated. The activation energies of the dyeings were also analysed with Durazol Scarlet Red 4 BAS. The results indicated that unlike the traditional scouring/bleaching processes the use of these reagents did not lead to adverse loss in strength. The moisture regain values also appreciated above the control indicating swelling، which might have resulted from decrystallization. The reduction of the activation energy as a result of the pretreatments confirmed the assertion. The performance of propan-2-ol was phenomenal. It suffices to say that propan-2-ol could replace the caustic soda kiering process with its attendant environmental hazards and often-difficult recycling procedure.

Risk analysis is an important technique to estimate impacts on the environment for adopting effective measures to avoid risks. This field study was conducted to investigate the risk of brick kiln (BK) smoke on the shoots of Acacia arabica. Different phenotypic parameters including morphology and growth of shoots and epidermal imprints of the leaves were studied in the vicinity of a brick kiln situated 500 meters away from Lahore-Raiwind Road، Lahore، Pakistan. Results show that smoke exposure has posed differential effects on shoots i. e. some shoots of same tree remained normal، others died and still others were badly affected by the smoke. Moreover، the number of leaves and fresh weight in the smoke affected shoots significantly reduced as compared with normal ones. The study of the epidermal imprints of the leaves of these normal and smoke effected shoots revealed that the mean values of the stomatal size of both adaxial and abaxial surfaces of the normal and smoke effected leaves were not statistically significant. However، the number of stomata on both epidermal layers of smoke effected leaves was significantly reduced as compared with normal ones. This study showed that due to the exposure to BK smoke، the growth of Acacia arabica trees in the field was significantly suppressed.

Influence of arbuscular mycorrhizal fungi (AMF) (Glomus etunicatum, G. intraradices and Glomus versiforme) and external phosphorus supplement (8 and 35 mg P Kg-1 soil) on leaf P, Zn, Cu and Fe nutrition of 4-month-old tea(Camellia sinensis) was studied in an glass house pot experiment. The highest leaf P concentration (up to 59.43% increase) was found in G. versiforme inoculated seedlings grown in the zero mg P Kg-1 soil, compared to the control seedlings. Higher level of Zn, Cu, and Fe concentrations were found in plants inoculated with G. intraradices as compared to other treatments. Our results showed that inoculation with G. intraradices had greater effect on uptaking of P, Zn, Cu, and Fe by tea seedlings than inoculation with either G. etunicatum or G. versiforme.

This study was conducted to determine soil properties that correlate with the arbuscular mycorrhizal fungal (AMF) spore numbers in semiarid calcareous soils of Hamadan province in northwestern of Iran. Soil samples from six sites managed differently were collected from a 0 to 30 cm depth. The results showed that land use and management systems had a significant effect on AMF spore number in soils. The mean spore number was found to fluctuate from 87 10g-1 to 172 10g-1 in coniferous woodland and dry farmland soils، respectively. The AMF spore numbers in soils exhibited a positive correlation with soil silt content، organic carbon/available P ratio، total nitrogen/available P ratio، basal respiration and fungal population، but a negative correlation with soil available P and available P/available K ratio. It may be concluded that soil management system، plant cover، silt content، available P are the main factors affecting AMF spore numbers in calcareous soils.

Carbosulfan (2, 3-dihydro-2, 2dimethyl-7-benzofuronyl [(dibutyl amino) thio] methyl] a carbamate insecticide and acaricide was administered orally at an effective dose of 48 mg/kg/day to albino mice for 5, 10, 20 and 30 days. Control mice received similar quantities of olive oil. Daily body weights were recorded and mice were sacrificed after 24 hours after the terminal exposure. The histologic examination of liver of the mice treated with carbosulfan for 10, 20 and 30 days revealed the dilation of central vein and sinusoids between hypertrophied hepatocytes. Vacuolization and hyalinization of hepatocytes with loss of radial arrangement. Treatment with carbosulfan for 20 days in female and male mice resulted in a significant decrease in protein and liver glycogen contents in female mice, whereas in male mice the glycogen was not changed significantly in the liver. The cholesterol content was increased significantly in male mice, but in female mice there was no significant change. Treatment with carbosulfan for 30 days caused significant decrease in DNA, RNA, protein, glycogen and significant increase in the level of cholesterol in male and female mice. Temporal study on liver enzymes displays treatment with carbosulfan for 20 days caused significant increase in LDH activity and significant decrease in Naà+=«, Mgjد, Cajد and no significant change in SDH, ASAT, ALAT, ACP activity in female mice, however in male mice the activity of liver enzymes was not changed significantly. Carbosulfan treatment for 30 days caused significant decrease in SDH, Na+K3
‎ے, Mgjد, Cajد, ACP activity, whereas LDH, ASAT, ALAT, AKP activity were increased significantly in the liver of male and female mice. The results of the present study suggests that the carbosulfan has adverse effects on liver functions leading to histologic and physiological impairment.

Measuring salinity of water at different depths along six transacts at the mouth of the wetland and along five tributaries connecting the wetland to the sea the extent of Caspian Sea penetration into Anzali Wetland was determined. The results demonstrated a depth-dependent salinity gradient extending up to 10 kilometres into the wetland. A pattern of saltwater and freshwater interface is presented and the role of this interface in enhancing sedimentation is discussed.