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21.
Sachin Kanta Rautaray Atmaram Mishra Om Prakash Verma 《Archives of Agronomy and Soil Science》2017,63(14):1993-2006
A field experiment was conducted in split plot design to examine the energy efficiency, productivity, and profitability of 6 rice based cropping systems for selected conservation agricultural (SCA) and the conventional (CNV) practices during the years 2010 to 2012. Results revealed that rice crop grown in wet season with SCA resulted in higher net energy, energy output: input ratio, energy productivity, and net returns as compared to CNV. Also, in the dry season, higher yield, net return, net energy and the net economic water productivity (NEWP) were noted for the SCA. Among the dry season crops, sunflower recorded highest net energy (57.2 GJ ha?1) followed by horsegram and cabbage. The NEWP was highest for babycorn (US $ 0.198 m?3), followed by cabbage and sweetcorn. However, the per cent increase in net return, net energy and the NEWP for SCA as compared to the CNV was highest for horsegram followed by sunflower. Despite having low system productivity, rice-sunflower and rice-horsegram cropping systems were more energy efficient with high net energy of 194.4 and 169.4 GJ ha?1, respectively. These two systems were low water demanding and helped in buildup of soil organic carbon, nitrogen (N), phosphorus (P) and potassium (K). 相似文献
22.
Kanta Gaihre Yam Singh Upendra D. Bible Wendie Fugice Jr Job Sanabria Joaquin 《水稻科学》2020,27(5):434-444
Soil-emitted nitrous oxide (N2O) and nitric oxide (NO) in crop production are harmful nitrogen (N) emissions that may contribute both directly and indirectly to global warming. Application of nitrification inhibitors, such as dicyandiamide (DCD), and urea deep placement (UDP), are considered effective approaches to reduce these emissions. This study investigated the effects of DCD and UDP, compared to urea and potassium nitrate, on emissions, nitrogen use efficiency and grain yields under direct-seeded rice. High-frequency measurements of N2O and NO emissions were conducted using the automated closed chamber method throughout the crop-growing season and during the ratoon crop. Both UDP and DCD were effective in reducing N2O emissions by 95% and 73%, respectively. The highest emission factor (1.53% of applied N) was observed in urea, while the lowest was in UDP (0.08%). Emission peaks were mainly associated with fertilization events and appeared within one to two weeks of fertilization. Those emission peaks contributed to 65%–98% of the total seasonal emissions. Residual effects of fertilizer treatments on the N2O emissions from the ratoon crop were not significant; however, the urea treatment contributed 2%, whereas UDP contributed to 44% of the total annual emissions. On the other hand, cumulative NO emissions were not significant in either the rice or ratoon crops. UDP and DCD increased grain yields by 16%–19% and N recovery efficiency by 30%–40% over urea. The results suggested that the use of DCD and UDP could mitigate N2O emissions and increase grain yields and nitrogen use efficiency under direct-seeded rice condition. 相似文献
23.
Chinmayee Priyadarshini Khuntia Basant Kumar Das Biswa Ranjan Samantaray Surya Kanta Samal & Bibhutendu Kumar Mishra 《Aquaculture Research》2008,39(3):301-310
Vibrio parahaemolyticus, an important pathogen of freshwater prawn, Macrobrachium rosenbergii causes high mortality. Four strains of V. parahaemolyticus were isolated from the gill, haepatopancreas, hemolymph and carapace of diseased prawn. The species were characterized based on biochemical and serological tests. On performing an antibiotic assay, these strains were found to be highly susceptible to cephalaxin, tetracycline and erythomycin. During the in vitro pathogenicity test, all the strains were found to be positive to the Congo red binding assay and to be haemolytic in nature, whereas an in vivo pathogenicity test revealed that 2 × 109 CFUs mL?1of bacteria induced disease symptoms such as black colouration on the carapace, red discolouration of the exoskeleton and loss of appendages within 6 days and 80% mortality. In histopathological studies, a prominent necrosis was seen in gill lamellae, and branchial arches were thickened at places due to hyperplasia and haemocytic infiltration. Hepatopancreatic tissue showed dilation of tubules, vacuolation of hepatocytes and marked necrosis in acinar cells. Development of an immunological technique for the detection and screening of V. parahaemolyticus infection and its treatment is highly important in freshwater prawn aquaculture. 相似文献
24.
Ingudam Bhupenchandra Anjali Basumatary Samiron Dutta Laishram Kanta Singh Namita Datta 《Journal of plant nutrition》2020,43(8):1175-1188
AbstractA field experiment was conducted at Horticultural Experimental Farm, Assam Agricultural University, Jorhat during the year 2015–17 to assess the impact of boron fertilization on dynamics of boron fractions in soil and crop yields in cauliflower–cowpea–okra cropping sequence. Five levels of boron (0, 0.5, 1.0, 1.5 and 2.0?kg ha?1) along with the recommended dose of NPK fertilizer were applied in soil in cauliflower once in each 2 years (2015–17) of experimentation to assess the direct effect of boron fertilization, while cowpea and okra were grown as a suceeding test crop to study the residual effects of boron fertilization in the cropping sequence. Among the different levels of boron, the highest content of all the boron fractions in soil was recorded at rate of 2?kg B ha?1 at different crop growth stages for all the three crops. Progressive decrease in content of all the boron fractions with crop ageing was noticed. The content of different boron fractions in soil follows the order readily soluble boron (RSB)<oxide bound boron (OXB)<organic bound boron (ORBB)<specifically adsorbed boron (SAB) <residual boron, respectively. The boron level of 2?kg B ha?1 was found to prominent in increasing the yield in all the crops. In respect of contributions of different boron fractions to yield of crops, oxide bound boron(2.10) was found to be the highest contributor of cauliflower yield, while the residual boron (1.10), contributed the highest to cowpea yield and organic bound boron fraction (1.24) was found to be most prominent contributor of boron in leveraging okra yield. 相似文献
25.
Mini P. Singh Kapil Goyal Manasi Majumdar Radha Kanta Ratho 《Tropical animal health and production》2011,43(1):111-114
The present study reports the first survey for the detection of antirabies antibodies in street and household dogs in India.
We aimed to check the efficacy of control programs for the disease in the Union territory of Chandigarh. The serum samples
were collected from 100 street and 50 household dogs and tested for the presence of antirabies antibodies by ELISA. As per
WHO criteria, a titre of >0.5 IU/ml of antirabies antibody in serum samples was taken as the protective level. Protective
antirabies antibody titre was found only in 1% of the street dogs and 16% of the pet dogs. The awareness among the pet dog
owners about the antirabies vaccination schedule was low as 18% did not know the vaccination status of the dog and 66% had
got the initial immunization done with only three doses and annual boosters were not given. A National Rabies Elimination
Program needs to be launched as a collaborative venture by both medical and veterinary practitioners to curb this deadly disease.
Also periodic surveys to test the status of antirabies IgG among dogs need to be carried out to ascertain the attainment of
WHO protective levels 相似文献
26.
• Background
The data on carbon pool and biomass distribution pattern of old-growth Pinus kesiya Royle ex. Gordon forests are not available. 相似文献27.
Roy Krishna Kanta Reza Md Mostofa Ali Muzahid-E-Rahman Md Anwar Md Babul Kishowar-E-Mustarin Kabir Muhammad Rezaul Malaker Paritosh Kumar Barma Naresh Chandra Deb Hossain Md Israil He Xinyao Chawade Aakash Singh Pawan Kumar 《Euphytica》2021,217(7):1-23
Euphytica - Genetic approaches often lead to the most cost-effective and efficient means to improve crops, especially those grown widely. But for most crops, cotton included, genetic improvement... 相似文献
28.
Mohammad Amzad Hossain Hikaru Akamine Ichiro Nakamura Yukio Ishimine Hitoshi Kuramochi 《Weed Biology and Management》2001,1(3):164-169
The present study describes the influence of temperature levels and planting time on the sprouting of rhizome-buds and the biomass production of torpedograss ( Panicum repens L.) in the Okinawa prefecture, Japan. Torpedograss planted in each month (1994–95) was grown for 210 days. Sprouting of the rhizome-bud of torpedograss was 92–96% at the temperature range of 20–35°C in an incubator, and the sprouting was not observed at the extreme low and high temperature of ≤5 and ≥45°C, respectively. The plant showed 40–72% emergence when grown in pots throughout the year in the ambient temperature range of 17–29°C. The percentage emergence was comparatively higher in March to September, and shoots elongated rapidly in the period from April to October when the temperature range of 22–29°C prevailed. Torpedograss-rhizome sown in the period from January to June obtained significantly higher biomass because higher temperatures prevailed in the following growth period from May to October, as compared with the torpedograss-rhizome sown in the period of July to December. The plant required higher temperatures for proper growth and development during the period of moderate (70–110 days after planting (DAP)) and fast growth phases (110 DAP to the last harvest). 相似文献
29.
Arup Kumar Mukherjee Nalini Kanta Mohapatra Parsuram Nayak 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(1):33-39
Attempts were made to estimate the area under the disease progress curve (AUDPC) of rice blast disease caused by Pyricularia grisea from two data points on the disease progress curve. Forty-two rice genotypes were exposed to high disease pressure in a nursery
over nine seasons. A conducive condition was created for maximum disease development through high nitrogen application, close
spacing and maintenance of high relative humidity. Disease severity was recorded on alternate days beginning from disease
initiation until the end of the epidemic. The estimation of AUDPC, and logistic and Gompertz apparent infection rates using
either all-points (AP) or two-point (TP) methods revealed significant correlations among them. This was also confirmed through
regression analysis and factor analysis. Hence, the estimation of AUDPC from two data points i.e. initial and final disease
scores of the disease progress curves is recommended as providing information similar to that from all the data points; this
should save valuable time, labour and economic resources. 相似文献
30.
Kenta Adachi Keiko Ohnishi Takashi Kuramochi Tatsuki Yoshinaga Sei-Ichi Okumura 《Fisheries Science》2014,80(3):445-450
Octopus (Amphioctopus) areolatus is an important marine cephalopod in Japan. We examined its diploid chromosome number, karyotype, and genome size (C value), and performed fluorescence in situ hybridization (FISH) using a vertebrate telomeric probe. The diploid chromosome number was 60 in embryonic cells, with 24 pairs of metacentric chromosomes, four pairs of metacentric/submetacentric chromosomes, and two pairs of submetacentric chromosomes. The mean C value was estimated to be 5.47 pg. From these findings, and those reported previously for other octopus species, we suggest that the factor causing the quantum change of C value in O. (A.) areolatus was genome duplication, and not polyploidy. In telomeric FISH analysis, hybridization signals were clearly observed in the telomeric regions of the chromosomes. This is the first report of FISH analysis of cephalopod chromosomes, and our findings suggest that the telomere sequence of O. (A.) areolatus is (TTAGGG) n , which may allow gene mapping in the future. 相似文献