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1.
Vegetation analysis provides the prerequisites to understand the overall community structure and function of any ecosystem and is a fundamental requirement for the precise evaluation of biodiversity. Although many studies have assessed floristic attributes of specific areas, there are still unexplored regions, as is the case of the mountain region in the Kashmir Himalayas. Current research highlighted the recent findings of the scientific characterization of floristic and ecological aspects on the forest flora found in the Bhimber hills, Pakistan. Floristically, a total of 93 species belonging to 80 genera in 41 families were recorded. The species distribution patterns across the families were disproportionate with half of the species contributed by 8 families and 25 families were monotypic. Based on the floristic analysis, Asteraceae was the largest family with 12% of species followed by Poaceae with (11%) species. PAST software, a multivariate ecological community analysis was used to classify the species similarities and differences among the different habitat types. According to the habitat wise distribution, 21% of species were growing in the natural forest habitat, while 15% of species were dispersed in highly distributed habitats along roadsides and 8% on pedestrians. In terms of functional diversity, the herbaceous growth form was dominant (58%). The biological spectrum revealed therophytes as the dominant life form as it indicates the disturbed habitat vegetation. The phytogeographical analysis revealed that the maximum (69%) species were native, while the minimum (31%) species were exotic. Thus, the study of these functional and habitat diversity patterns can significantly improve our understanding of the ecological aspects of the flora in the geographical location. This information may additionally be useful in devising management plans to ensure sustainable utilization and better management of forest landscapes in this Himalayan region.  相似文献   
2.
An experiment was conducted to test the effect of different doses of 2, 4 and 8?g/2?kg of soil of Pochonia chlamydosporia against the root-knot nematode (Meloidogyne incognita) on Phaseolus vulgaris. It was observed that inoculation of plant with the nematode alone, and 15?days prior to fungal inoculation, reduced the plant growth when compared with the plant with fungal application followed by the nematode. Plant length, fresh and dry weight, chlorophyll, carotenoid, protein contents and nitrate reductase activity decreased in nematode-infested plants. Application of higher dose of 8?g/2?kg of soil of P. chlamydosporia increased all the plant growth parameters as well as biochemical parameters. Highest number of galls per root system was recorded on the plants infested with nematode but not treated with the fungus. However, application of fungus prior to nematode inoculation improved the plant growth and reduced the number of galls and the number of egg masses per root system.  相似文献   
3.
Bitter gourd (Momordica charantia L.) was inoculated with root-knot nematode Meloidogyne incognita to investigate the anatomical abnormalities in the affected roots. Soon after inoculation the second-stage juveniles (J2) entered at or near the root caps and migrated intercellularly towards the zone of vascular differentiation. Discrete giant cells were observed after three days of inoculation. The nematode induced hypertrophy and hyperplasia near the giant cells. After six days, the juveniles moulted to their third stage (J3). At the same, time giant cell size and density of giant cell cytoplasm increased. The continuity of vascular strands remained unaffected. Between 12 and 24 days of inoculation the giant cells enlarged several times and became multinucleate and enclosed dense and granular cytoplasm. The nematodes became almost pyriform 18 days after inoculation. The orientation of vascular strands changed, due to hypertrophy, hyperplasia and enlargement of the nematode. After 30 days of inoculation the nematodes developed into mature females and started egg laying. A large amount of parenchyma transformed into abnormal xylem.  相似文献   
4.
Meloidogyne incognita is a plant pathogen causing root-knot disease and loss of crop yield. The present study aimed to use Trichoderma harzianum as a biocontrol agent against plant-parasitic nematodes and used press mud, which is a solid waste by-product of sugarcane, as a biocontrol agent and biofertilizer. Therefore, the combined application of T. harzianum and press mud may enhance nematode control and plant growth. Elemental analysis of press mud using scanning electron microscopy (SEM) integrated with an Energy Dispersive X-ray (EDX) analyzer revealed the presence of different elements such as C, O, Mg, Si, P, K, Ca, Cu and Zn. In addition, a greenhouse study was conducted to investigate the combined effects of press mud and T. harzianum on M. incognita reproduction and growth and the biochemical features of Psoralea corylifolia. The results showed that plant length, dry biomass, leaf area, the number of seeds per plant, chlorophyll a, chl b, carotenoid content, nitrate reductase, carbonic anhydrase, and nitrogen content were significantly increased (P ≤ 0.05) in the T2 plants (plants were treated with 100 g of press mud + 50 mL T. harzianum before one week of M. incognita inoculation), over inoculated plants (IC). Antioxidant enzyme activity of ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) in the foliage of P. corylifolia was significantly increased when plants were treated with press mud + T. harzianum. A significant reduction in the number of egg masses, nematode population, and root-knot index (RKI) was found in plants with T2 plants. These results suggest that the combined application of T. harzianum and press mud has the potential to control the M. incognita infection and can be used as an environmentally safe alternative to chemical nematicides and also help in the removal of sugarcane waste that causes environmental pollution.  相似文献   
5.
Cryptosporidium, a protozoan parasite, can cause cryptosporidiosis which is a gastrointestinal disease that can infect humans and livestock. Cattle are the most common livestock that can be infected with this protozoan. This study was carried out to determine the prevalence of Cryptosporidium infection in cattle in Kuantan, Pahang, Malaysia and to find out the association between the occurrence of infection and 3 different ages of cattle (calves less than 1 year, yearling, and adult cattle). The samples were processed by using formol-ether concentration technique and stained by modified Ziehl Neelsen. The results showed that 15.9% (24/151) of cattle were positive for Cryptosporidium oocysts. The occurrence of Cryptosporidium in calves less than 1 year was the highest with the percentage of 20.0% (11/55) followed by yearling and adult cattle, with the percentage occurrence of 15.6 % (7/45) and 11.8% (6/51), respectively. There was no significant association between the occurrence and age of cattle and presence of diarrhea. Good management practices and proper hygiene management must be taken in order to reduce the infection. It is highly important to control the infection since infected cattle may serve as potential reservoirs of the infection to other animals and humans, especially animal handlers.  相似文献   
6.
A calcium-activated neutral protease (CANP) has been purified 2,800 fold, to near homogeneity, from human platelets. The purification procedure involved ammonium sulfate fractionation of the platelet cytosol followed by chromatography on Sephacryl S-200, DEAE-Sephacel, Agarose-Hexylamine, Agarose-Octylamine and alpha-casein-Sepharose 4B affinity gel. The protease consisted of two polypeptides of Mr = 74,000 and 28,000 as judged on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It hydrolyzed [methyl-14C] alpha-casein at a significant rate of 37 degrees C which was, therefore, used as an exogenous substrate. Microtubules and intermediate filament proteins were also susceptible to hydrolysis by the purified protease. It attained maximum activity at 0.06 uM CaCl2 and displayed two pH maxima: one at 5.5 and the other at 6.5. The protease was fully active in the presence of MnCl2 and was about 75% active with BaCl2 and SrCl2. Among the actinomycete protease inhibitors, leupeptin, antipain and pepstatin, the order of inhibition was: leupeptin greater than antipain greater than pepstatin. The protease was also inhibited by sulfhydryl modifying agents.  相似文献   
7.
The 949 bp promoter fragment upstream from the translation initiation site of the GUSP gene encoding a universal stress protein was isolated from the genomic DNA of Gossypium arboreum. Some putative cis-acting elements involved in stress responses including E-box, ABRE, DPBF-box, and MYB-core elements were found in the promoter region. In an Agrobacterium-mediated transient expression assay, strong activation of the GUSP full promoter region occurred in tobacco leaves following dehydration, abscisic acid, salt, heavy metal, gibberellic acid and dark treatments. Deletion analysis of the promoter revealed that the dehydration, abscisic acid and salt responses were affected by the deletion between −208 and −949 bp and showed 2–4-fold induction. However, in response to dark, gibberellic acid and heavy metals the induction was only 2-fold. These findings further our understanding of the regulation of GUSP expression. This is an important study as no report of this universal stress protein promoter is available in literature.  相似文献   
8.
Heat‐shock proteins (HSP) are molecular chaperones for protein molecules. These proteins play an important role in protein–protein interactions such as, folding and assisting in the establishment of proper protein conformation and prevention of unwanted protein aggregation. A small HSP gene GHSP26 present in Gossypium arboreum responds to dehydration. In the present study, an attempt was made to overcome the problem of drought stress in cotton. A cDNA of GHSP26 was isolated from G. arboreum, cloned in plant expression vector, pCAMBIA‐1301 driven by the cauliflower mosaic virus 35S promoter and introduced into Gossypium hirsutum. The integration and expression studies of putative transgenic plants were performed through GUS assay; PCR from genomic DNA, and quantitative real‐time PCR analysis. Transgenic cotton plants showed an enhanced drought tolerance, suggesting that GHSP26 may play a role in plant responsiveness to drought. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
9.
Single-stranded telomeric overhangs are ∼200 nucleotides long and can form tandem G-quadruplex (GQ) structures, which reduce their accessibility to nucleases and proteins that activate DNA damage response. Whether these tandem GQs further stack to form compact superstructures, which may provide better protection for longer telomeres, is not known. We report single-molecule measurements where the accessibility of 24–144 nucleotide long human telomeric DNA molecules is interrogated by a short PNA molecule that is complementary to a single GGGTTA repeat, as implemented in the FRET-PAINT method. Binding of the PNA strand to available GGGTTA sequences results in discrete FRET bursts which were analyzed in terms of their dwell times, binding frequencies, and topographic distributions. The binding frequencies were greater for binding to intermediate regions of telomeric DNA compared to 3′- or 5′-ends, suggesting these regions are more accessible. Significantly, the binding frequency per telomeric repeat monotonically decreased with increasing telomere length. These results are consistent with telomeres forming more compact structures at longer lengths, reducing accessibility of these critical genomic sites.  相似文献   
10.
Effects of the root-knot nematode (Meloidogyne incognita) on lentil (Lens culinaris) were studied under greenhouse conditions. The plants were inoculated with 250, 500, 1000, 2000 and 4000 J2 per plant. Plant growth, yield, nodulation, seed weight, chlorophyll, nitrogen, phosphorus and potassium, (NPK) contents, as compared to control, were found decreased in all the nematode infected plants. The extent of reduction increased with an increase in inoculum levels. The reductions were significant at 500 J2 and at higher inoculum levels, i.e. 1000, 2000 and 4000 J2 per pot over the control. An increase in inoculum level caused enhancement in galling, egg mass production and nematode population. At higher inoculum levels, the population of the nematode in the root as well as in the soil increased to a greater magnitude than at lower inoculum levels. On the contrary, reproduction factor (RF) and rate of population increase (RPI) decreased with increasing inoculum levels.  相似文献   
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