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91.
Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura.Overall 10,957 individual trees belonging to 46 family,103 genera and 144 species were counted at ≥30 cm DBH(diameter at breast height) using 28 permanent belt transects with a size of 1 ha(10 m × 1000 m).Four different tree communities were identified.The primary forests was dominated by Shorea robusta(mean density 464.77 trees ha-1,105 species) and Schima wallichii(336.25 trees ha-1,82 species),while the secondary forests was dominated by Tectona grandis(333.88 trees ha-1,105 species) and Hevea brasiliensis(299.67 trees ha-1,82 species).Overall mean basal area in this study was 18.01m 2 ·ha-1 ;the maximum value was recorded in primary Shorea forest(26.21 m 2 ·ha-1).Mean density and diversity indices were differed significantly within four different communities.No significant differences were observed in number of species,genera,family and tree basal cover area.Significant relationships were found between the species richness and different tree population groups across the communities.Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumulation of native oligarchic small tree species.Seventeen species were recorded with <2 individuals of which Saraca asoka(Roxb.) de Wilde and Entada phaseoloides(L.) Merr.etc.extensively used in local ethno-medicinal formulations.The present S.robusta Gaertn dominated forest was recorded richer(105 species) than other reported studies.Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests.Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur.The analysis of FIV suggested a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary T.grandis L.dominated community. 相似文献
92.
In this study, a freshwater fish Channa punctatus was exposed to subacute concentrations of synthetic pyrethroid insecticides (cypermethrin and λ-cyhalothrin) for 96 h to
evaluate their impact on the levels of nucleic acids and protein in its different organs. Significant enhancement in the level
of DNA was recorded in all tissues of the fish at high concentration of cypermethrin, whereas RNA and protein contents increased
in tissues at all concentrations of cypermethrin tested. In contrast, λ-cyhalothrin treatment caused an increase in the level
of DNA only in liver and brain, whereas increase of RNA and protein varied to different levels in different tissues. Cypermethrin
treatment induced RNA/DNA ratio in all fish organs tested, whereas λ-cyhalothrin caused a sharp decrease in the ratio. Protein/DNA
ratios were found to be tissue specific in treatments with both of the insecticides. The results clearly indicated that both
of these pyrethroids exerted their effects in a similar manner in fish liver but differed in other tissues. These insecticides
acted as potential biomodulators in C. punctatus, though following different routes. The results may be an indicator of aquatic pollution affecting freshwater fauna and flora
and thus signaling the need for strict regulation on the indiscriminate input of pyrethroids from agricultural sites. 相似文献
93.
R. Shankar H. Shivananda Murthy H. R. Sujatha E. G. Jayaraj C. S. Tejpal V. S. Chinthamani 《Aquaculture International》2012,20(1):1-12
A 60-day feeding trial was conducted to evaluate the effect of dietary nucleotide on growth, survival, immunity and resistance
to white muscle disease and Aeromonas hydrophila infection in freshwater prawn (Macrobrachium rosenbergii). The nucleotide was supplemented at 0, 1.5, 2.25 and 3.0 g/kg diet. The test diets were fed for 60 days in triplicate groups
of prawns, which had initial weight of 0.27 g. At the end of the feeding trial, growth was recorded and non-specific immune
parameters, such as, prophenol oxidase activity, superoxide anion production, total haemocyte count and total serum protein,
were studied in haemolymph samples. Phenol oxidase activity and superoxide anion production were significantly (P < 0.05) higher in prawns fed nucleotide-based diets. Total haemocyte count and haemolymph were higher (P < 0.05) in prawns fed nucleotide-based diets. The relative per cent survival of prawn after the challenge test against white
muscle disease was significantly (P < 0.05) higher in prawn fed nucleotide-incorporated diets. However, there was no effect of nucleotide supplementation on
growth and survival of prawn. 相似文献
94.
Siddaiah Chandra Nayaka Arakere C Udaya Shankar Munagala S Reddy Siddapura R Niranjana Harishchandra S Prakash Hunthrike S Shetty Carmen N Mortensen 《Pest management science》2009,65(7):769-775
BACKGROUND: Maize is one of the staple food crops grown in India. Fusarium verticillioides (Sacc.) Nirenberg is the most important fungal pathogen of maize, associated with diseases such as ear rot and kernel rot. Apart from the disease, it is capable of producing fumonisins, which have elicited considerable attention over the past decade owing to their association with animal disease syndromes. Hence, the present study was conducted to evaluate ecofriendly approaches by using a maize rhizosphere isolate of Pseudomonas fluorescens (Trev.) Mig. and its formulation to control ear rot disease and fumonisin accumulation, and also to study the capacity to promote growth and yield of maize. In vitro assays were conducted to test the efficacy of P. fluorescens as a seed treatment on seed germination, seedling vigour and also the incidence of F. verticillioides in different maize cultivars. The field trials included both seed treatment and foliar spray. For all the experiments, P. fluorescens was formulated using corn starch, wheat bran and talc powder. In each case there were three different treatments of P. fluorescens, a non‐treated control and chemical control. RESULTS: Pure culture and the formulations, in comparison with the control, increased plant growth and vigour as measured by seed germination, seedling vigour, plant height, 1000 seed weight and yield. P. fluorescens pure culture used as seed treatment and as spray treatment enhanced the growth parameters and reduced the incidence of F. verticillioides and the level of fumonisins to a maximum extent compared with the other treatments. CONCLUSION: The study demonstrates the potential role of P. fluorescens and its formulations in ear rot disease management. The biocontrol potential of this isolate is more suited for fumonisin reduction in maize kernels intended for human and animal feed. Copyright © 2009 Society of Chemical Industry 相似文献
95.
H. Shivanada Murthy Prakash Pavadi N. S. Sudhakar N. Manjappa V. S. Chinthamani R. Shankar 《Journal Of Applied Aquaculture》2013,25(1):50-60
Fish compost was prepared using wastes of deep sea fish, Pricanthus hamrur, along with coffee husk as bulk material in a simple and less expensive method. The prepared fish compost was evaluated on growth and survival of Indian major carp, Labeo rohita, and production of both phytoplankton and zooplankton in 25 m3 cement cisterns. Juveniles of Labeo rohita (6.0 ± 0.35 g) were stocked @ 15 numbers/cistern. Two treatments with initial dosages of compost namely, 5 kg/cistern (2000 kg/ha), 2.5 kg/cistern (1000 kg/ha), and cattle dung @ 12.5 kg/cistern (5000 kg/ha), served as control in first installment. Subsequent monthly application of second and third installments was carried out with dosages of 1 kg/cistern (400 kg/ha) and 0.5 kg/cistern (200 kg/ha) in fish compost treatments and 2.5 kg (1000 kg/ha) of cattle dung (control). The fish were fed 30% protein diet at a rate of 5% of the fish biomass. Significantly higher growth (127.0 g) and survival (89.75%) of Labeo rohita were recorded in 2.5 and 0.5 kg fish compost treatment than in control and other treated group. Higher and sustained plankton production also was observed in compost treated tanks. 相似文献
96.
Sangram Ketan Sahoo Shiba Shankar Giri Manoranjan Paramanik 《Journal Of Applied Aquaculture》2013,25(2):144-149
An experiment was conducted to ascertain the initial rearing period required for Horabagrus brachysoma larvae before releasing them into the nursery tank for fingerling production. Hatchlings were reared for 7, 14, or 21 days in larval rearing tanks before stocking to nursery tanks. The 7-day-old larvae were significantly smaller at the end of the 2-week nursery rearing, but over the course of nursing, the 7-day-old larvae caught up to the 14- and 21-day larvae. The specific growth rate (SGR) of 7-day larvae was highest among the three treatments. However, mortality of 7-day larvae was the highest among the groups. Hence, it appears important to rear the larvae at least 2 weeks before stocking for fingerling production so as to increase survival rate. 相似文献
97.
98.
Padinhate Purayil Suresh Babu Kalkuli Mariappa Shankar Badami Ramalingappa Honnananda Purandara Ballyaya Abhiman 《Aquaculture International》2014,22(4):1451-1456
Immune response in rohu treated with an immunomodulator is usually evaluated employing either non-specific immune parameters or traditional antibody-based tools. In the present study, a monoclonal antibody-based immunodot has been developed for evaluating antibody titre in rohu as a preliminary tool to ensure antibody response due to the effect of an immunomodulator, which can be used for routine field level analysis. The immunodot was sensitive enough to determine rohu immunoglobulin up to 15 μg/ml. Application of the immunodot for evaluating enhancement in immune response could be successfully demonstrated in probiotic fed rohu. 相似文献
99.
B. Vijaya Ramnath S. Rajesh C. Elanchezhian A. Santosh Shankar S. Pithchai Pandian S. Vickneshwaran R. Sundar Rajan 《Fibers and Polymers》2016,17(1):80-87
Nowadays, automotive, packaging and sport equipment industries are using natural fibre based composite materials as they are cheap, abundantly available and having a lot of ecological advantages. The main objective of this paper is to introduce a new concept of fibre twisting and to investigate the effect of twisting and the fibre orientation on the mechanical properties of bio degradable green composites. Here, the composites are fabricated by vacuum assisted compression molding technique in which the problems of hand lay process are eliminated. Here, two fibers namely twisted neem and twisted kenaf are sandwiched between layers of glass fibres to enhance the stiffness and strength of the laminates. Initially, the fibers are alkalized to increase the mechanical properties. The result shows that there is a significant improvement in mechanical properties of composites due to the presence of twisted fibers. It also shows the influence of fiber orientation on mechanical properties. 相似文献
100.
Chandra Prakash Kushwaha Shri Kant Tripathi Gopal Shankar Singh Kaushlendra Pratap Singh 《Annals of Forest Science》2010,67(3):310-310