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71.
Summary To find out an effective isolation distance in olitorius jute experiments were conducted for three years in two planting designs; in one the cultivar with the dominant marker allele was planted at the centre and the cultivarcarrying the recessive marker allele was planted around and in the other the planting arrangement was just the reverse of the former. A total of nearly 20 lac seedlings were counted. Irrespective of the planting designs, at the minimum distance from the pollen source outcrossing was found to be at its maximum which, however, decreased with the distance. Directions had no influence on cross pollination in this species. At a distance beyond 9.0 metres outcrossing was found to be absent.  相似文献   
72.
Two-year rice (Oryza sativa L.)-based crop rotation of “maize (Zea mays L.) relay cropped by horse gram (Dolichos biflorus L.) in the first year followed by upland rice in the second year”, was reported earlier to increase phosphorus (P) uptake by rice through enhancing native arbuscular mycorrhizal (AM) activities. This crop rotation was compared with three other rice-based crop rotations practiced by the upland rice farmers of eastern India for AM-mediated P acquisition of upland rice through on-farm experiment in farmers' participatory mode during wet seasons of 2004, 2005, 2006, and 2007 in fixed plots. The farmers' rotations included (1) green gram (Phaseolus aureus) in first year followed by upland rice in second year; (2) black gram (Phaseolus mungo) in first year followed by upland rice in second year; and (3) radish (Raphanus sativus) in first year followed by upland rice in second year. “Maize–horse gram/rice” rotation encouraged maximum native AM fungal colonization (10.4–38.8%) and P uptake (2.2–2.6 mg P/g plant) by rice over other three farmers' rotations tested. Rice grain yield was also highest (2.25–2.35 t/ha) in the maize–horse gram/rice rotation.  相似文献   
73.
Community forestry is an approach for mitigating deforestation and forest degradation by managing the forest resources for benefitting neighboring communities. Monetary benefits and costs are associated in a community forest during conservation and management of a forest. For sustainable forest management, the benefit should be more than cost which is a contesting issue of research. So, this study was conducted in a community forest of the central part of Nepal with the help of 80 household surveys and a focus group discussion. The firsthand information collected at the site is complimented by forest product harvest and cost-related secondary information. It was observed that the total annual harvest of timber was 60 cubic feet, pole was 8 cubic feet, firewood was 1,110 Bhari,1 fodder was 4,388 Bhari, and leaf litter was 590 Bhari. To manage a forest, people were involved in fencing, thinning, and meetings. Management cost was six times higher than administration cost. The benefit from firewood and fodder was more due to the dependency of people in a forest for enhancing their livelihood. The higher value of benefit cost ratio indicates that the Community Forest User Group benefited from community forest management.  相似文献   
74.
Sixteen clinically healthy New Zealand white rabbits of either sex were divided into 2 equal groups (I and II) of 8 animals each. Under thiopental sodium (2.5%) anaesthesia a 2 x 3 cm full-thickness abdominal wall defect in the mid-ventral abdominal wall was created and repaired with an acellular dermal graft (ADG) in all the animals of group I (test group). In animals of group II (control group) a full-thickness linear midline abdominal muscular wall incision was made and repaired with a continuous suture pattern using 2-0 nylon.  相似文献   
75.
A total of 52 samples (22 cloacal swabs and 30 pooled ovaries and oviducts) from hens with a history of a 25 to 40% drop in egg production from 30 flocks were examined for the isolation of infectious bronchitis virus in embryonated chicken eggs. Five isolates were obtained: three from cloacal swabs and two from reproductive organs. These isolates were identified and characterized on the basis of agar-gel-precipitation, hemagglutination, and neutralization tests and other physicochemical characteristics.  相似文献   
76.
Cellular immune response of 6-week-old chickens infected with fowl adenovirus type-1 was evaluated by both in vivo and in vitro assay. In vitro assay, enumerating peripheral T lymphocyte by alphanaphthyl acetate esterase staining, revealed that cellular immunity appeared as early as 1 week post-infection and was maintained up to 5 weeks post-infection. In vivo assay by phytohaemagglutin skin test showed cellular immunity until 2 weeks post-infection. Thereafter no immunity was observed by this assay.  相似文献   
77.
Chir pine (Pinus roxburghii) is an important tree species that grows all along the Himalayas. Wood specific gravity of chir pine before and after removal of extractives from wood increment cores was assessed from a 22-years-old progeny test in Himachal Pradesh, India. These values averaged 0.433 and 0.425, respectively. A large amount of genetic variation among the 58 half-sib families was found as indicated by range of values, additive coefficient of variation, variance estimates and narrow-sense heritability values for these traits. Moisture and extractive content averaged 86.259% of oven-dry weight and 2.003% of extractive-free oven-dry weight, respectively. Wood extractive content was highly variable and the family differences were highly heritable (h f2 = 0.5831). There was wide variability in moisture content, but a large portion of it was due to environmental or non-additive component of genetic variation. Heritability on family mean basis was found to be lower than that on individual tree basis for each trait. Estimated gain in specific gravity resulting from 30 to 50% family selection ranged from 0.0080 to 0.0127. Growth data and specific gravity were not significantly correlated implying that selection for higher growth rate would not necessarily result in reduction in wood specific gravity in chir pine.  相似文献   
78.
Jute fibers have immense potential to be used as natural fillers in polymeric matrices to prepare biocomposites. In the present study jute fibers were surface treated using two methods: i) alkali (NaOH) and ii) alkali followed by silane (NaOH+Silane) separately. Effects of surface treatments on jute fibers surface were characterized using fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyses. Further, the effects of surface treatments on jute fibers properties such as crystallinity index, thermal stability, and tensile properties were analyzed by X-ray diffraction method (XRD), thermo gravimetric analysis (TGA), and single fiber tensile test respectively. The effects of surface treatment of jute fibers on interphase adhesion between of poly(lactic acid) (PLA) and jute fibers were analyzed by performing single fiber pull-out test and was examined in terms of interfacial shear strength (IFSS) and critical fiber length.  相似文献   
79.
Sixteen tenorrhaphies were performed at mid-metatarsal region in eight buffalo calves. A 2-cm long gap was created in the superficial digital flexor (SDF) tendon in all animals. The gap was immediately repaired with acellular grafts in animals of group I, 1% glutaraldehyde-preserved tendon allografts in group II, and in group III the defect was repaired with autografts (control group). The contralateral limb in each animal was operated after an interval of 60 days and the animals underwent the same procedure according to the designed groups. Gross observation revealed filling of host tendon-graft junction with fibrous connective tissue. Increased vascularity was seen in group I when compared with group II and III. Graft was resorbed in animals of group I and III, whereas partial absorption of graft was seen in group II. Histological observations on day 30 revealed restoration of cellularity in acellular graft and fragmentation and resorption of glutaraldehyde-preserved graft. Graft was replaced by newly formed fibrous connective tissue. Tissue reaction around polygalactin suture consisted of plasma cells, lymphocytes and macrophages. On day 90, most of the acellular graft was replaced by newly formed fibrous connective tissue. In group II the majority of graft portion remained at the site and was in a state of resorption. In the control group it was difficult to distinguish between the host tendon and the graft. Scanning electron microscopical observation showed densely packed neoformed tissue at host tendon-graft junction. Hydrolysis and invasion of connective tissue between polygalactin suture filaments, resorption of graft with cavity formation and dissolution of ground substance were observed.  相似文献   
80.
The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of caprylic acid (CA), monocaprylin (MC, monoglyceride ester of CA) and sodium caprylate (SC) on Edwardsiella ictaluri, E. tarda, Streptococcus iniae and Yersinia ruckeri in Mueller Hinton broth (MHB) were investigated. In addition, the bactericidal kinetics of CA and MC on the aforementioned pathogens in MHB, and that of SC in water, were determined. The MIC of CA and SC on E. ictaluri, E. tarda, S. iniae and Y. ruckeri were 7.5 and 50 mM, 7.5 and 50 mM, 10 and 25 mM, and 7.5 and 25 mM respectively. For MC, the MIC was in between 2.5 and 5 mM for all the pathogens. The MBC of CA, MC and SC on E. ictaluri, E. tarda, S. iniae and Y. ruckeri were 10, 5 and 100 mM; 10, 5 and 100 mM; 15, 5 and 75 mM; and 10, 5 and 75 mM respectively. The three lipid molecules exerted a substantial antimicrobial effect on the fish pathogens studied. The results indicate that CA and its derivatives could potentially be used for treating and controlling bacterial fish diseases, but extensive validation studies in fish are needed before recommending their usage.  相似文献   
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