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31.
Beneficial interactions of arbuscular mycorrhizal fungi (AM Fungi) and plant growth promoting rhizobacteria (PGPR) have an important role in keeping agriculture sustainable. The present study reports the positive effects of AM fungi (Rhizophagus intraradices, Rhizophagus fasciculatum), Burkholderia seminalis and dual inoculation of these two strains on growth of Lycopersicon esculatum and Capsicum annuum plant under drought stress conditions. Each treatment was replicated six times and was arranged in a complete randomized block design. A significant increase in terms of biomass, root length, shoot length, and chlorophyll content was observed with the plants inoculated with these beneficial microorganisms. Accumulation of proline was found to be less in AM fungi inoculated plants suggesting the role of it in mitigating the water stress. A positive correlation between % colonization and chlorophyll content, root length, catalase activity, and guaiacol peroxidase has been observed depicting the importance of the AM fungi in drought tolerance.  相似文献   
32.
The objectives were to determine the content and composition of lipophilic extractives, particularly fatty and resin acids, in three Scots pine trees from each of two stands in northern Sweden, one that was due for thinning and one due for final cutting. Extractives content of branches, needles, barks, stem discs from branch whorls, and sapwood and heartwood samples from various heights was measured. Fractions had very different concentrations and distributions of extractives due to differences in the composition of tissues. The needles had the highest total extractive concentration (around 150?kg/ton d.w.), followed by the branches, bark, timber from the final cut stand, and then the pulpwood and timber from the thinning stand. The final cut stand generally provided higher yields of extractives in assortments per hectare than the thinning stand; the difference was five-fold for timber, three-fold for whole trees, two-fold for branches, needles and bark and similar for pulpwood. This information on the content and composition of extractives in different tissues, and the dependence of these quantities on tree age could be used together with information on conventional stand data such as tree numbers and dimensions to guide the selection and management of feedstocks for biorefineries.  相似文献   
33.
Tilletia indica Mitra is the causal agent of Karnal bunt of wheat, an important disease prevalent in several countries. The disease is internationally quarantined and the pathogen due to its heterothallic nature shows high variability. In the present study, we compared the pathogenic behaviour of various isolates of T. indica collected from different geographical locations of India and genetically characterized monosporidial (Ms) culture lines raised from these isolates of the pathogen. Pathogenic variability revealed existence of three pathotypes based on aggressiveness on a set of differential host genotypes. Monosporidial culture lines viz., 5 each from KB1, KB2, KB4 and KB5 and three lines of KB3 were established and analyzed genetically using 12 Universal Rice Primers (URPs). Amplification showed 98.44% polymorphism and primer URP 13R produced 100% polymorphic bands. Maximum similarity (83%) was between KB1MsB and KB1MsD as calculated by Jaccard’s similarity coefficient, whereas, minimum similarity was between KB1MsC and KB4MsB; KB1MsE and KB3MsA (46%). Three groups were formed among all Ms culture lines. One major group consisted of 13 lines with approximately 70% similarity, the second group consisted of 7 culture lines showing 55% similarity and the third group consisted of 3 Ms lines. URPs were able to differentiate the Ms culture lines raised from different T. indica isolates and the results indicated heterogeneity in the pathogen population.  相似文献   
34.
Morphology of the nematode Viguiera dicrurusi Gupta, 1960 harboured by Dicrurus macrocercus albirictus (Hodgson) (Passseriformes: Dicruridae) from Baruipara in 24-Pargonas (South) district, West Bengal, India was studied by light and scanning electron microscopy (SEM). This represents the first study of V. dicrurusi using SEM. Scanning electron micrographs provided detailed information about the nature of pseudolabial plates, number and shape of teeth, dentate nature of striae, and the relative position of vulva, anus and phasmid opening in female. A detailed morphometrical comparison of this species with Viguiera viduae Chabaud, 1960 described from Dicrurus forficatus from Madagascar indicates that V. viduae is a junior synonym of V. dicrurusi. Two other species, Viguiera bhujangai Jehan, 1972 and Viguiera adsimilisai Sood et Kalia, 1978 are considered species inquirendae.  相似文献   
35.
Objective  The study was undertaken to evaluate the use of ketamine, xylazine, and diazepam along with a local retrobulbar nerve block for routine phacoemulsification in the dog.
Animals  Ten clinically healthy mixed-breed dogs of either sex, weighing between 10 and 15 kg.
Procedures  Ten mixed-breed dogs were selected for unilateral cataract removal by phacoemulsification. Standard preoperative preparations for cataract surgery were followed. Pre-anesthetic medication consisted of atropine sulfate (0.02 mg/kg, SC). Anesthesia was induced by xylazine HCl (1.0 mg/kg, IM) followed by ketamine (5.0 mg/kg, IM). Anesthesia was maintained subsequently with IV ketamine and diazepam to effect and depth of anesthesia was assessed clinically by pedal reflex and jaw reflex. After induction of anesthesia, a retrobulbar nerve block was performed using 2 mL of 2% lignocaine. Eye position was graded after retrobulbar block and IOP was examined preoperative, post-anesthetic, 6 h postoperative and 24 h after surgery. Phacoemulsification was performed using the phaco-chop technique and an intraocular lens was placed. Anesthetic recovery and postoperative recovery following surgery was recorded.
Result  The exposure of the globe in all the dogs was adequate; the desired central fixation of the eye was obtained and surgery could be performed uneventfully. The mean IOP recorded after induction of anesthesia was 15.75 ± 0.82, which was not significantly ( P  > 0.01) different from pre-anesthetic values (14.85 ± 0.85).
Conclusion  Phacoemulsification was successfully performed with this anesthetic regimen without encountering major intraoperative or anesthetic complications.  相似文献   
36.
This study was undertaken to elucidate the effect of ammonia‐generating diet on serum and follicular fluid ammonia and urea levels, serum oestrogen and progesterone concentrations and granulosa cell growth and secretion parameters in ewes (Ovis aries). Ewes were fed with 14% CP diet (control) or ammonia‐generating diet or ammonia‐generating diet plus soluble sugar. The serum and follicular fluid ammonia and urea level, serum oestrogen and progesterone levels and granulosa cell (obtained from ovaries of slaughtered ewes) growth parameters and secretory activities were estimated. Ammonia‐generating diet (high‐protein diet) increased the serum ammonia and urea concentration. Supplementation of soluble sugar significantly reduced the ammonia concentration in serum with comparable levels as in control group; however, the urea level in the same group was higher than that observed in control group. Supplementation of soluble sugar significantly reduced the follicular fluid ammonia concentration; however, the level was significantly higher compared to control group. Supplementation of soluble sugar brought down the follicular fluid urea level comparable to that observed in control group. Oestrogen and progesterone levels remained unchanged in ewes fed with different types of diet. Oestrogen and progesterone secretion were significantly lowered from granulosa cells recovered from ewes fed with high ammonia‐generating diet. Low metabolic activity and high incidence of apoptosis were observed in granulosa cells obtained from ovaries of ewes fed with ammonia‐generating diet.  相似文献   
37.
Spatial distribution, abundance and assemblage of termites depend mainly on the local conditions and habitats in which they thrive. Striking differences are observed in the species richness, number of clades and functional diversity of termite assemblage between different habitats. This study aim was to examine effect of human interference in the diversity of wood destroying termite in forest areas as well as managed and unmanaged plantations in South India. Termites attacking trees and wooden logs were collected from forest areas, managed plantations and unmanaged plantations. The termites collected were identified and compared for species abundance, richness and species diversity. Results show that the species composition and species diversity of the wood destroying termites vary according to the conditions. The species diversity measures revealed that there is a significance variation among the forest fauna and plantations. The forest areas have the highest species composition compared to plantations. Species richness is high forest areas. Even though the abundance of termites are more in unmanaged plantations, there is no significant difference related to species diversity among the managed and unmanaged plantations.  相似文献   
38.
In this work, a series of fibrous electrets was prepared by applying electrostatic charge onto a polypropylene nonwoven fabric using corona charging process. The charging process parameters were systematically varied and their effects on charge decay were examined. A double exponential function composed of two exponentials of very different characteristics explained the charge decay characteristics very well. It was hypothesized that two charges of different nature were present in corona-charged fibrous electrets. One of the charges could be ascribed to deposition of ions onto the electret surface and the other charge could be attributed to internal polarization caused by ionic displacement. The overall charge decay could be then explained by the quick decay of the surface charge in addition to the slow decay of the bulk charge. The slow-decay component was found to contribute more to the overall charge decay with respect to a change in applied voltage. With a decrease in applied voltage, the contribution of the slow-decay component was increased. The rate of quick-decay component as well as the rate of slow-decay component was found to increase with the increase in applied voltage. With respect to a change in charging time, the quick-decay and slow-decay components were found to contribute almost equally to the overall charge. This was also true with respect to a change in distance between electrodes, except at a very high distance. With an increase in charging time, the rate of quick-decay component as well as the rate of slow-decay component started decreasing till the minimum values were obtained and increased thereafter. A similar observation was made on the role of distance between electrodes in determining the rate of quick-decay as well as the rate of slow-decay components.  相似文献   
39.
This study was carried out to investigate the effect of supplementing culture medium with different concentrations of taurine and melatonin, on buffalo oocyte in vitro meiotic maturation and embryo development. In experiment 1, oocytes were matured in vitro and the cleaved embryos were cultured in the same following seven culture medium; (i) control (TCM 199 + 10% SS); (ii) control + 0.5 m m taurine; (iii) control + 1 m m taurine; (iv) control + 3 m m taurine; (v) control + 5 μ m melatonin; (vi) control + 10 μ m melatonin and (vii) control + 50 μ m melatonin. In experiment 2, based on the results of experiment 1, to examine the synergistic effect of antioxidants, the oocytes were matured in culture medium (TCM199 + 10% SS), supplemented with both taurine at 1 m m and melatonin at 10 μ m concentration and the cleaved embryos were cultured in the same medium. Supplementation of taurine at 1 m m concentration in the culture medium resulted in a higher (p < 0.05) transferable embryo (TE) yield when compared with control (20.6% vs 14.1%). Supplementation of melatonin at 10 and 50 μ m concentration in the culture medium resulted in a higher (p < 0.05) meiotic maturation rate (90.3% and 88.8% respectively) and TE yield (28.4% and 27.2% respectively), than the other treatments. In experiment 2, the TE yield did not improve by supplementing the culture medium with both taurine and melatonin, when compared with melatonin alone. In conclusion, the results of this study demonstrated that, enriching the culture medium with taurine and melatonin, improves in vitro embryo production efficiency in buffaloes. In particular, a high TE yield was obtained by enriching the culture medium with 10 μ m melatonin.  相似文献   
40.
Gastroenteritis of viral origin has emerged as a major cause of morbidity and mortality in dogs during the last two decades. Amongst the viral etiologies responsible for gastroenteritis in dogs, canine parvovirus (CPV) is considered as the most pathogenic. The disease is characterized by hemorrhagic enteritis, bloody diarrhoea and myocarditis in young pups. The present study was carried out to examine alterations in oxidative stress indices in the erythrocytes from dogs suffering from gastroenteritis with or without canine parvoviral infection as confirmed by CPV-DNA amplification from faeces using specific primers for CPV-2 as well as CPV-2a and CPV-2b variants by polymerase chain reaction (PCR). The present investigation utilized clinical cases of dogs with signs of acute diarrhea (n = 56), and 14 more apparently healthy dogs of similar age group. Erythrocytic oxidative stress indices such as lipid peroxides level and antioxidant enzymes like superoxide dismutase and catalase activity, and blood micro-mineral (iron, copper, cobalt and zinc) status were analyzed in each dog (n = 70). The acute cases of gastroenteritis in dogs were associated with altered erythrocytic lipid peroxidation as evident by estimation of malonaldehyde (MDA) concentration. The activities of antioxidant enzymes catalase and superoxide dismutase, the first line of antioxidant defense against damaging effects of free radicals, were also altered. The alterations in oxidative stress indices were more pronounced in cases with involvement of canine parvovirus as compared to parvo-negative cases. Our results also revealed decreased blood zinc level in diarrhoea in dogs irrespective of involvement of canine parvovirus.  相似文献   
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