We inoculated them with our stain and incubated them on shaker for 24 hours. After 24 hours incubation, we took O.D at 600nm and plotted a graph. To check effect of different temperatures on rhizospheric nitrogen bacterial growth: We took 6 flasks (100ml), and added 20ml L-broth in each flask and autoclaved it. We inoculated them with our stain. We selected different temperatures 4°C, 15°C, 37°C.
Lemna species are the most resistant to toxicants, yet can be killed by high concentrations of heavy metals. What was taken from this study was that certain pollutants can cause a decrease in growth of duckweed to the extent where the plant dies. What I deduced is that none of these pollutants are any of the pollutants that I will be testing, meaning that the pollutants that I will be testing are dangerous towards the growth of duckweed. Professor Oron has a doctorate in sciences relating to soil and water meaning that he has extensive knowledge on the subject, making his research valid and a good source to
.1 Soil sampling and bacterial isolation A total of 17 soil samples were collected from the rhizospheres of various crop plants at two sites located in Yangzhou city, Jiangsu province, China (See Table 1). The soil samples were collected from a depth of 1–15 cm, put in polythene bags, and transferred to the laboratory. One gram was taken from each soil sample and added to 10 ml of sterilized distilled water. Serial dilutions of this mixture, up to 10-7 were then prepared. Nutrient agar medium (peptone 10.0 g, beef extract 3.0 g, sodium chloride 5.0 g, agar 20.0 g per liter and final pH 7.0) was prepared and autoclaved at 121°C for 30 min.
Agar cultures medium was incubated inside oven at room temperature between 27 to 30 oC. The incubation time was depends on the growth of the microorganism and also the purpose of incubation. 3.1.6 Maintenance of fungi isolates Fungi isolate was maintained on Potato Dextrose Agar (PDA) medium.The culture was restreaked on a new respective plates every two weeks.The composition of PDA medium per liter of distilled water is as follows: Commercial Potato Dextrose Agar powder 39g/L 3.1.7 Preparation of 3,5- Dinitrosalicylic (DNS) reagent 3,5-Dinitrosalicylic (DNS) reagent was prepared by mixing 3,5 DNS powder, 2M Sodium Hydroxide(NaOH), Potassium Sodium Tartrate and distilled water. Solution A was prepared by dissolving 300 g potassium sodium tartrate into 200mL of 2M NaOH. 2M NaOH was prepared by dissolving 8g of NaOH powder into 200mL distilled water.
Purification of glucoamylase The crude culture filtrate obtained after centrifugation was concentrated 5 times using rotary vacuum evaporator (EYELA Rotary Evaporator N 1000 Japan) followed by precipitation of enzyme at 40C using chilled acetone16. Precipitated protein was collected by centrifugation at 5,000 rpm for 15 mins at 40C. The precipitate was resuspended in 10 ml 0.1 M acetate buffer (pH 4.8) and enzyme activity was measured. DEAE-Cellulose chromatography 10 ml of the resuspended precipitate was applied to the previously equilibrated DEAE-Cellulose column 17. The enzyme was eluted with 0.1 M acetate buffer (pH 4.8) contaning a linear gradient of (0-0.1M) Nacl at a flow rate of 20 ml/h.
In step two of the lab, seven different test tubes were filled with solutions that have different molarities. Then seven different cylinders of potatoes were selected, each at 3cm long. Then each potato cylinder was cut in half. Then each two halves were placed in each test tube. Each test tube was stirred approximately every ten-fifteen minutes.
The dried mushroom samples were further heated at 105 ºC overnight until constant weight obtained for moisture content determination. The samples were incinerated at 550 ºC for 24 h and reweighed to determine ash content. MicroKjeldahl method was employed for the crude protein content (N × 4.38). The crude fat was determined by extracting a known weight of sample in Soxhlet apparatus using petroleum ether as a solvent. Total carbohydrates calculated by the difference.
Deficiency symptoms in plants Co deficiency cause reduce in plant growth, reduce in seed germination, also reddening of leaves, stems, petioles. In leguminous crops cause yellowing leaves or small root nodules and in some crops it causes N deficiency. Uptake and accumulation of C in plants The accumulation and uptake of Co is tested by root, stem, leaves of treated plants. Mostly the amount of cobalt required by plants is determined by soil drenching method in which we apply diluted chemicals directly to the base of the plant for deep penetration • E.g. Co is given to soybean (Glycine max) plants in pot culture by soil drenching method.
For a given soil and a given compaction effort there is one moisture content called “optimum moisture content” that occurs in a maximum dry density of the soil. Those moisture contents both greater and smaller than the optimum value will result in dry density less than the maximum Chen, 1999. For the present study Laboratory modified Procter test were performed as per the AASHTO T-180; generally disturbed samples of soil particles passing sieve sizes 19mm mixed with water to form samples at various moisture contents ranging from the dry state to wet state. These soils are compacted into the mold to a five equal layers, each receiving 56 numbers of blows from a 4.89kg weighted hammer at a 450mm height. This process is then repeated for various moisture contents and the dry densities are determined for each.
coli transformants was isolated by alkaline lysis method (Sambrook et. al., 1989). Clones obtained on plates were inoculated in 5ml LB broth containing appropriate antibiotic and incubated overnight at 37°C under shaking conditions. The cells were harvested by centrifugation at 7000rpm for 5min and resuspended in 200 μl of GTE (Glucose-tris-EDTA) buffer. For lysis two volumes i.e.