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81.
Brinjal plants ( Solanum melongena L.) grown under moisture stress conditions in a glasshouse were treated with three anti-transpirants, namely cycocel, limewash and potassium chloride, to study their influence on chlorophyll content, soluble protein and photosynthetic rate. Moisture stress imposed at each of the three growth stages decreased chlorophyll content, soluble protein and photosynthetic rate. Of the anti-transpirants investigated, cycocel performed better than limewash and po-tassium chloride. 相似文献
82.
83.
Monika BHADAURIA Sangeeta SHUKLA Ramesh MATHUR Om P. AGRAWAL Sadhana SHRIVASTAVA Sonia JOHRI Deepmala JOSHI Varsha SINGH Deepak MITTAL Satendra Kumar NIRALA 《Integrative zoology》2008,3(4):311-321
Exposure to mercuric chloride (HgCl2; 5 mg kg?1 body weight; i.p.) induced oxidative stress in mice and substantially increased lipid peroxidation (LPO) and oxidized glutathione (GSSG) levels, decreased the level of reduced glutathione (GSH) and various antioxidant enzymes in liver and also increased the activities of liver marker enzymes in serum. Therapy with propolis extract, a resinous wax‐like beehive product (200 mg kg?1 orally, after mercury administration), for 3 days inhibited LPO and the formation of GSSG and increased the level of GSH in the liver. Release of serum transaminases, alkaline phosphatase, lactate dehydrogenase and γ‐glutamyl transpeptidase were significantly restored after propolis treatment. The activities of antioxidant enzymes, that is, superoxide dismutase, catalase, glutathione‐S‐transferase and glucose‐6‐phosphate dehydrogenase, were also concomitantly restored towards normal levels after propolis administration. These observations clearly demonstrate that propolis treatment augments antioxidant defense against mercury‐induced toxicity and provide evidence that propolis has therapeutic potential as a hepatoprotective agent. 相似文献
84.
Probal Jyoti Doley Kabita Sarma Pranab Chandra Kalita Ranjana Goswami Arup Kalita Rupan Sarkar Chethan Gollahalli Eregowda Parimal Roychoudhary Om Prakash Choudhary 《Anatomia, histologia, embryologia》2023,52(2):223-233
The present study was undertaken to characterize the ultrastructural morphology of the blood cells of commonly reared chickens in the state of Mizoram, India under backyard poultry farming. For this study, 2 ml of whole blood was aseptically collected from the wings veins of 12 chickens of three different breeds namely the Zoar, Aseel and Rhode Island Red and processed for ultrastructural imaging under standard protocols. Under scanning electron microscopy (SEM) the matured erythrocytes of Zoar, Aseel and Rhode Island Red appeared elliptical in shape while the leukocytes and thrombocytes appeared round in shape with variable surface modifications. Under transmission electron microscopy (TEM) the granules of the heterophils of Zoar, Aseel and Rhode Island Red appeared predominantly fusiform in shape, the granules of the eosinophils appeared round in shape and that of the basophils appeared pleomorphic in shape. The cytoplasm of the monocytes, medium-to-large lymphocytes and thrombocytes of Zoar, Aseel and Rhode Island Red under TEM appeared to be vacuolated and granular while that of the small lymphocytes appeared to be granular but non-vacuolated. The study concluded that the ultrastructural characteristics of the blood cells of the three breeds of chicken studied were almost similar to the blood cells of other birds reported earlier. 相似文献
85.
Ekambaranellore Prakash Patan Shaik Sha Valli Khan Thoguru Jonh Vivek Sreenivasa Rao Elu Singh Meru 《Journal of Forest Research》2006,11(5):329-335
In vitro clonal multiplication of Pterocarpus santalinus L. was achieved using mature nodal explants of a 10-year-old elite quality tree. Combinations of serial transfer technique
and incorporation of antioxidants (250 mg/l L-ascorbic acid and 50 mg/l citric acid) into the culture medium helped to minimize medium browning and improve explant survival
during shoot sprouting. About 70% of explants were sprouted on Murashige and Skoog (MS) liquid medium containing 4.4 μM 6-benzyladenine (BA). The explant harvest period also influenced the bud break and shoot sprouting in nodal explants. The
combination of 4.4 μM BA and 2.2 μM thidiazuron (TDZ) was found to be the most suitable growth regulator for obtaining the highest percentage of nodal segment
sprouting (74%–75%), the number of secondary shoots per primary shoot (two or three), the shoot length (5–6 cm), the number
of new nodal segments generated per active explant (four or five), and the multiplication coefficient (3.5) within 6 weeks.
Repeated subculturing of nodal explants obtained from shoot cultures enabled continuous production of healthy axillary shoots.
At the end of the sixth passage, about 90% of nodal explants produced five or six healthy green shoots, each being about 6.6 cm
long with six or seven nodes. Multiplication coefficient was also increased from the first subculture (5.4) to the sixth subculture
(8.3). The best rooting response was achieved on solidified half-strength MS medium supplemented with 4.9 μM indole-3-butyric acid (IBA). About 70% of the micropropagated plantlets were established successfully in 20-cm pots containing
a mixture of soil and farmyard manure (4 : 1 ratio) and formed new leaflets. 相似文献
86.
Budget of nutrient in plant and soil, and their rates of recycling in three types of traditional agroforestry systems in mid
elevations of the western Himalaya were studied. Concentration of nitrogen and potassium was significantly higher in fruits
and leaves than in branches, boles, and litter. Grewia optiva, an important fodder tree, was found to be rich in potassium, vegetable crops in nitrogen, and weeds in phosphorus. Maximum
store of nutrients was estimated in aboveground biomass of agrihortisilvicultural system: nitrogen 532, phosphorus 40, potassium
461, calcium 400, and magnesium 298 kg/ha; it was closely followed by that in agrihorticultural system, and both these had
sbout 2-fold higher nutrient stock as compared to agrisilvicultural system. In the case of the former two systems, considerable
quantity of nutrients up to nitrogen 169, phosphorus 14, potassium 165, calcium 97, and magnesium 65 kg/ha, for example in
agrihortisilvicultural system, was recycled through debris of crops and weeds, and tree leaf litter, while the recycling rate
was almost half in agrisilvicultural system. Through ‘harvest’ potassium was depleted in the largest quantity from the system,
followed by nitrogen, magnesium, calcium, and phosphorus; much higher loss occurred through agricultural and/or horticultural
edible parts as compared to fuel and fodder biomass. For example, the loss through agricultural crops and horticultural fruits
for nitrogen in agrihortisilvicultural system was up to 75 percent and 38 percent respectively of the total annual uptake.
This heavy loss makes the system unstable from a nutrient point of view particularly for nitrogen and potassium until external
inputs are added through organic and inorganic fertilizers. Agrihortisilvicultural system is remarkably efficient in view
of biomass productivity for fuel, fodder and fruits, and also from nutrient point of view provided losses through harvest
are compensated externally. 相似文献
87.
Endoglucanase has been isolated from Aspergillus aculeatus. The purified enzyme showed a single band and had a molecular weight of 45,000 Da as indicated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with a specific activity of 1.4 units/mg. The purified enzyme was identified as endoglucanase, showing a high specific activity toward CM-cellulose and low specific activity toward Avicel. The activity of the isolated enzyme was optimum at a pH of 5.0 and temperature of 40 degrees C, respectively. The isoelectric point of the enzyme was 4.3. T(m) was found to be 57 degrees C. The treatment of the endoglucanase with diethylpyrocarbonate resulted in the modification of the histidine residues present in the enzyme, with a concomitant loss of 70% of the original enzymatic activity. However, carbodiimide completely inactivated the endoglucanase. The results show that the enzyme is able to sustain 50% of its activity even when heated at 90 degrees C for a period of 5 h. Endoglucanase can be used in the controlled hydrolysis of cellulose and other cellulose-rich foods. It can be used in the development of targeted functional foods from agrimaterials for value addition in the food chain. 相似文献
88.
The advent of modern forces and the changes in socioeconomic patterns of forest dwellers have increased the pressures on the forests. In order to mitigate such pressures and also to protect the forests and wildlife the model of protected areas networks has shifted and enhanced such pressures in the unprotected natural forests due to several reasons. Being a low profile category of protected status and continuous human settlements, the present study highlights the case of dry deciduous forests of Sarguja district of Chhattisgarh state of India. The major objectives of this study were to quantify the status of forests and wildlife and also to determine the extent of anthropogenic disturbances faced by the dry deciduous forests of central India. Transect and silent drive count methods were used for sampling wildlife and quadrat method was used for sampling vegetation. Besides, the local uses of various forest produces were also studied in view of understanding the people dependency on forests. The forest vegetation, in the study area, was pre-dominated by Shorea robusta, which had Madhuca indica, Diospyrus melanoxylon and Buchnania lanzan as the major companion species. The forest had either the high girth class mature tree species or the saplings. The low vegetation cover and density were due to the high anthropogenic pressures mainly in the form of heavy livestock grazing and collection of ethnobotanically important species. The study though reveals that the area is not rich in wildlife and the forest is fragmented, the area still supports some important species, which include many rare and endangered plants and animals. The findings of this study have been discussed in view of the management and conservation of the forest and wildlife in the dry deciduous forests. 相似文献
89.
Longer forest rotation ages can potentially increase accumulation of carbon in harvested wood products due to a larger proportion of sawlogs that can be used for manufacturing durable wood products such as lumber and plywood. This study quantified amounts of carbon accumulated in wood products harvested from loblolly pine (Pinus taeda L.) stands grown in Mississippi by extending rotation ages traditionally used to manage these stands for timber. The financial viability of this approach was examined based on carbon payments received by landowners for sequestering carbon in standing trees and harvested wood products. Results indicated a potential to increase carbon accumulated in wood products by 16.11 metric tons (t) of carbon dioxide equivalent (CO2e) per hectare (ha) for a rotation increase of 5 years and 67.07 tCO2e/ha for a rotation increase of 65 years. Carbon prices of $50/tCO2e and $110/tCO2e would be required to provide a sufficient incentive to forest landowners to extend rotations by 5 and 10 years, respectively. With 2.8 million ha of loblolly pine stands in Mississippi, this translates to a possible increase in wood products carbon of 45 million tCO2e and 80 million tCO2e for harvest ages increased by 5 and 10 years, respectively. Higher carbon prices lengthened rotation ages modestly due to low present values of carbon accumulated with long rotations. 相似文献
90.