Seasonal Changes in Nitrate Reductase Activity and Nitrogen Contents of Upland Rice at Low and Optimum N Fertility     

S. K. Pal  U. R. Pal 《Journal of Agronomy and Crop Science》1986,156(1):13-17

A field experiment was conducted at the Livestock Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar, India during the wet season (June—October) of 1980 with the objectives of characterizing the seasonal changes in in vivo nitrate reductase activity (NRA) and N contents of upland rice cultivars grown under rainfed condition at low (0 kg N/ha) and optimum (80 kg N/ha) N fertility.
In vivo NRA increased initially up to panicle initiation stage (50 days after sowing) and declined, thereafter, until 90 days. Leaf NO₃-N content paralleled with in vivo NRA throughout crop season. Total N content of leaves and stem declined with advance in crop age, whereas panicle N content increased with the crop development. Optimum N fertility (80 kg N/ha) always resulted in higher NRA, NO⁻₃ and total N contents of rice plants.  相似文献   

Effect of Component Densities on the Productivity of Soybean/Maize and Soybean/Sorghum Intercrop     

U. R. Pal    T. O. Oseni  J. C. Norman 《Journal of Agronomy and Crop Science》1993,170(1):66-70

Field experiments were conducted during the wet seasons of 1986 and 1987 at the Yandev Agricultural Experiment Station to investigate the effects of component density on the yield of sorghum or maize intercropped with soybean. Seed yield of the monocrops of sorghum, maize and soybean were higher than the individual components in the intercrops. Yields of component crops in the intercrop varied significantly with the components population density. The sorghum/soybean intercrops which had LER (Land Equivalent Ratio) up to 1.40 in 1986 and 1.35 in 1987 were more productive than soybean/maize intercrop with maximum LER of 1.28 and 1.34 respectively during 1986 and 1987. Similarly the ATER (Area X Time Equivalent Ratio) of sorghum/soybean was greater than in soybean/maize. However, for maximum productivity of sorghum or maize intercropped with soybean, optimum population of one component crop plus 1/2 optimum population of the companion crop is recommended depending on which of the crop is regarded as main or minor crop.  相似文献   

Canopy and Seasonal Profiles of Nitrate Reductase Activity in Field Grown Grain Sorghum     

U. R. Pal  J. M. Kununka 《Journal of Agronomy and Crop Science》1987,159(3):206-211

Field experiments were conducted at the Livestock Research Centre of G.B. Pant University of Agriculture and Technology, Pantnager, India during wet season (June-September) of 1978 with the objectives of characterizing canopy and seasonal profiles of in vivo nitrate reductase activity (NRA) of grain sorghum ( Sorghum bicolor [L.] Moench) cultivars.
Canopy profile of NRA was studied on hybrid CSH 5 at 45, 55, 70, 80 and 95 days after sowing, whereas seasonal profile of NRA was studied in six sorghum cultivars — hybrid CSH 5 and pure line varieties CSV 4, SPV 100, SPV 101, SPV 103 and SPV 106 beginning at 30 days until 95 days after sowing.
Canopy profile studies indicated that fully expanded recently matured leaves possessed higher levels of in vivo NRA than unexpanded immature as well as older leaves. Seasonal profiles of in vivo NRA showed different trends in different cultivars. Cultivars SPV 100, SPV 101, SPV 103 and SPV 106 demonstrated two peaks of in vivo NRA/plant/day at 44 and 95 days. On the other hand, hybrid CSH-5 had only one peak at 51 days and cultivar CSV 4 had none.  相似文献   

Residues of cypermethrin,fenvalerate and deltamethrin on cauliflower     

Parm Pal Singh  Balwinder Singh  Raminderjit Singh Battu 《Phytoparasitica》1990,18(2):153-158

Following the application of Cypermethrin, fenvalerate and deltamethrin to a cauliflower crop at rates of 50, 50 and 12 g a.i. ha^-1, the maximum initial deposits of these insecticides on heads and leaves were 1.10 and 0.75, 1.14 and 0.60, and 0.32 and 0.12 mg kg^-1, respectively. These residue values for fenvalerate were less than the maximum residue limit (MRL) of 2 mg kg^-1 for this crop. While the maximum initial deposits of Cypermethrin and deltamethrin on cauliflower leaves were less than their respective MRL values of 1 and 0.2 mg kg^-1 for brassica leafy vegetables, it took one day for their residues on cauliflower heads to decline below this level.  相似文献   

Antifungal activity of the stem bark of Ailanthus excelsa     

Joshi BC  Pandey A  Chaurasia L  Pal M  Sharma RP  Khare A 《Fitoterapia》2003,74(7-8):689-691

The methanol extract of stem barks of Alianthus excelsa was partitioned with chloroform. The chloroform extract showed fungistatic and fungicidal activity against Aspergillus niger, A. fumigatus, Penicillium frequentence, P. notatum and Botrytis cinerea.  相似文献   

In vitro activities of Maesa lanceolata extracts against fungal plant pathogens   总被引：2，自引：0，他引：2  

Okemo PO  Bais HP  Vivanco JM 《Fitoterapia》2003,74(3):312-316

In vitro tests were carried out using extracts of Maesa lanceolata var. goulungensis weir against a broad range of fungal plant pathogens such as Phytophthora cryptogea, Trichoderma virens, Aspergillus niger, Phoma sp., Fusarium oxysporium, Pythium ultimum, Cochliobolus heterostrophus, Rhizoctonia solani, Sclerotium rolfsii and Pyrenophora teres. M. lanceolata extracts were very active against all the pathogens tested except P. ultimum and R. solani.  相似文献   

REP-PCR Analysis of Pasteurella multocida Isolates from Wild and Domestic Animals in India     

Saxena MK  Singh VP  Kumar AA  Chaudhuri P  Singh VP  Shivachandra SB  Biswas A  Sharma B 《Veterinary research communications》2006,30(8):851-861

Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was used to characterize 67 field isolates of Pasteurella multocida originating from different animal species and geographical regions of India. REP-PCR was found to be rapid and reproducible (three repeats were done). These isolates yielded different 23 profiles which were clustered into eight groups. The discrimination index was moderate (D value 0.83). Somatic and antigenic typing of the isolates did not reveal any correlation with REP-PCR profiles. There was no host-specific, type-specific, region-specific or pathenogenicity-specific pattern. The REP profiles of isolates obtained from wild animals were similar to those obtained from domestic animals. Two common bands were present in all the isolates irrespective of somatic or antigenic types. The results were not comparable with earlier findings, which had shown high discrimination index and correlation with disease presentation. Saxena, M.K., Singh, V.P., Kumar, A.A., Chaudhuri, P., Singh, V.P., Shivachandra, S.B., Biswas, A. and Sharma, B., 2006. REP–PCR analysis of Pasteurella multocida isolates from wild and domestic animals in India. Veterinary Research Communications, 30(8), 851–861  相似文献   

Morbidity Pattern of the 27th Indian Scientific Expedition to Antarctica     

Abhijeet Bhatia  Ranabir Pal 《The Forestry Chronicle》2012,23(3):231-238.e2

  相似文献   

Infectivity of porcine circovirus type 2 DNA in semen from experimentally-infected boars   总被引：1，自引：0，他引：1  

Madson DM  Ramamoorthy S  Kuster C  Pal N  Meng XJ  Halbur PG  Opriessnig T 《Veterinary research》2009,40(1):10-Feb;40(1):10

Porcine circovirus type 2 (PCV2) is an economically important pathogen. It has been demonstrated that PCV2 DNA can be detected in boar semen by PCR; however, the biological relevance of this is unknown. The objectives of this study were to determine if semen positive for PCV2 DNA is infectious (1) in a swine bioassay, or (2) when used for artificial insemination. For the first objective, 4-week-old pigs were inoculated intraperitoneally with PCV2 DNA-negative (bioassay-control; n = 3), PCV2a DNA-positive (bioassay-PCV2a; n = 3), or PCV2b DNA-positive (bioassay-PCV2b; n = 3) raw semen, or PCV2 live virus (bioassay-positive; n = 3), respectively. Pigs inoculated with PCV2 DNA-positive semen and PCV2 live virus became viremic and developed anti-PCV2 antibodies indicating that the PCV2 DNA present in semen was infectious. For the second objective, three Landrace gilts were inseminated with PCV2 DNA-negative semen (gilts-controls) from experimentally-infected boars, and six gilts were artificially inseminated with semen positive for PCV2a DNA (gilts-PCV2a; n = 3) or PCV2b DNA (gilts-PCV2b; n = 3). Serum samples collected from the gilts in all groups remained negative for anti-PCV2 antibodies for the duration of the experiment. In addition, fetal serum samples from all 105-day-gestation fetuses were negative for anti-PCV2 antibodies or PCV2 DNA. Under the conditions of this study, PCV2 DNA-positive semen was not infectious when used to artificially inseminate gilts; however, it was demonstrated to be infectious in a swine bioassay model and therefore is a potential means of PCV2 transmission amongst swine herds.  相似文献   

Dynamics of soil organic carbon and nitrogen associated with physically separated fractions in a grassland-cultivation sequence in the Qinghai-Tibetan plateau     

Xiao Ming Shi  Xiao Gang Li  Rui Jun Long  Bhupinder Pal Singh  Zhuo Ting Li  Feng Min Li 《Biology and Fertility of Soils》2010,46(2):103-111

This study is aimed at quantifying organic carbon (C) and total nitrogen (N) dynamics associated with physically separated soil fractions in a grassland-cultivation sequence in the Qinghai-Tibetan plateau. Concentrations of organic C and N of soil, free and occluded particulate organic matter (OM), and aggregate- and mineral-associated OM in different land uses are increased in the following order: 50 years cultivation < 12 years cultivation ≤ native grassland. The prolonged cropping of up to 50 years markedly affected the concentrations of free and occluded particulate OM and mineral-associated OM. After wet-sieving, 43% of native grassland soil mass was found in >1−10 mm water-stable aggregates that stored 40% of bulk soil organic C and N; only 16% and 7% of soil mass containing 16% and 7% of bulk soil organic C and N was >1−10 mm water-stable aggregates of soils cultivated for 12 years and 50 years, respectively. This indicated that losses of soil organic C and N following cultivation of native grassland would be largely related to disruption of >1–10 mm size aggregates and exposure of intra-aggregate OM to microbial attack. Organic C and N concentrations of soil aggregates were similar among aggregate size fractions (>0.05−10 mm) within each land use, suggesting that soil aggregation process of these soils did not follow the hierarchy model. The increase of the C-to-N ratio of free and occluded particulate fractions in the cultivated soils compared to the grassland soil indicated a greater loss of N than C.  相似文献