Soil loss tolerance values for different physiographic regions of Central India     

Brij Lal  Lakaria  H. Biswas  & D. Mandal  † 《Soil Use and Management》2008,24(2):192-198

In India, a single soil loss tolerance ( T ) value of 11.2 Mg/ha is by default used for formulating land restoration strategies for all soil types, climates and vegetation covers. However, this single 'T' value does not represent a true picture of soil loss tolerance under all land uses. The objective of our study was to develop adjusted ' T ' values for Central India using soil infiltration rate, bulk density, total organic carbon, erodibility and soil pH. Soil state was defined using a quantitative model involving different soil functions which were used to convert soil parameters to a 0 to 1 scale. The normalized values were then multiplied by appropriate weighing factors based on relative importance and sensitivity analysis of each indicator. Based on overall assessment, each soil mapping unit was categorized into soil groups I, II or III. A general guideline of USDA – Natural Resource Conservation Service (USDA-NRCS) was followed to calculate soil loss tolerance for each soil group using effective soil depth. Adjusted ' T ' values for Central India ranged from 2.5 to 12.5 Mg/ha compared with a default value of 11.2 Mg/ha. Use of these values for soil mapping units will improve conservation planning and assist with planning the development of sustainable agriculture.  相似文献   

Antimicrobial activity of saponins from Acacia auriculiformis     

Mandal P  Sinha Babu SP  Mandal NC 《Fitoterapia》2005,76(5):462-465

Acaciaside A and B, two acylated bisglycoside saponins originally isolated from the funicles of Acacia auriculiformis, are known to have antihelminthic activity. Their antifungal and antibacterial activities were investigated. Complete inhibition of conidial germination of Aspergillus ochraceous and Curvularia lunata was recorded at 300 microg/ml or less whereas to inhibit the growth of Bacillus megaterium, Salmonella typhimurium and Pseudomonas aeruginosa 700 microg/ml or higher concentrations of the mixture was required. Two catabolic enzymes, phosphofructokinase and isocitrate dehydrogenase, responded differentially in fungi and bacteria against sublethal concentrations of the compound when assayed from their cell free extracts. An increased specific activity of the enzymes in bacteria and a decrease activity in fungi indicate a possible different mechanism of inhibition of saponins on the organisms tested.  相似文献   

Metabolic responses of tea (<Emphasis Type="Italic">Camellia</Emphasis> sp.) to exogenous application of ascorbic acid     

Amarchand Chordia Murugan  Jibu Thomas  Raj Kumar Rajagopal  AbulKalamAzad Mandal 《Journal of Crop Science and Biotechnology》2012,15(1):53-57

Effects of exogenous application of ascorbic acid on physiological and metabolic changes in tea were investigated in the present study. The highest improvement in yield was evident in response to regular application (a day after every harvest) of ascorbic acid at 600 ppm followed by 400 ppm. Foliar application of ascorbic acid (600 ppm) at regular intervals enhanced chlorophyll a and b contents besides a significant increase in total polyphenols and catechins when compared to the untreated control. Exogenous application of ascorbic acid at alternate harvesting rounds increased the activity of polyphenol oxidase whereas ascorbate peroxidase remained unchanged. An increase in phenylalanine ammonia lyase activity was noticed with foliar application of ascorbic acid irrespective of its concentrations. Theaflavins and thearubigins of made tea showed an increase when ascorbic acid was applied with 400 and 600 ppm at alternate intervals. The scores of brewed tea liquor characteristics, viz. infusion, color, strength, and briskness were higher even at the lower concentration of ascorbic acid treatment. Results suggest that foliar application of ascorbic acid (400 ppm) proved to be a useful measure to improve the yield, physiological attributes, and antioxidant properties of tea.  相似文献   

Phenotypic and genetic characterization of Edwardsiella tarda isolated from pond sediments     

Maiti NK  Mandal A  Mohanty S  Mandal RN 《Comparative immunology, microbiology and infectious diseases》2009,32(1):1-8

The extent of genotypic and phenotypic diversity of Edwardsiella tarda isolated from pond sediment was assessed by SDS-PAGE, Plasmid Profiling and ERIC-PCR. SDS-PAGE of whole cell protein extracts reveals 20-23 discrete bands with molecular wt of 14-110 kDa. Several bands with molecular weight range of 38-83 kDa were present in all the isolates. Numerical analysis of protein electrophoregram delineated the isolates into four clusters. Two different types of plasmids having molecular mass of 23 kDa and 29 kDa were obtained by plasmid profiling. About 51% of the isolates carried both the plasmids. ERIC-PCR generates 3-7 bands with molecular mass of 14-1013 bp. Numerical analysis differentiated the ERIC pattern into 5 clusters at 60% similarly level. It was concluded that out of three methods ERIC-PCR was found to be more sensitive for intraspecific typing of E. tarda and can be used as a potential tool for epidemiological studies in the future.  相似文献   

Estimation of (co)variance components and genetic parameters of greasy fleece weights in Muzaffarnagari sheep     

A. Mandal  F.W. C. Neser  R. Roy  P.K. Rout  & D.R. Notter 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(1):22-29

Variance components and genetic parameters for greasy fleece weights of Muzaffarnagari sheep maintained at the Central Institute for Research on Goats, Makhdoom, Mathura, India, over a period of 29 years (1976 to 2004) were estimated by restricted maximum likelihood (REML), fitting six animal models including various combinations of maternal effects. Data on body weights at 6 (W6) and 12 months (W12) of age were also included in the study. Records of 2807 lambs descended from 160 rams and 1202 ewes were used for the study. Direct heritability estimates for fleece weight at 6 (FW6) and 12 months of age (FW12), and total fleece weights up to 1 year of age (TFW) were 0.14, 0.16 and 0.25, respectively. Maternal genetic and permanent environmental effects did not significantly influence any of the traits under study. Genetic correlations among fleece weights and body weights were obtained from multivariate analyses. Direct genetic correlations of FW6 with W6 and W12 were relatively large, ranging from 0.61 to 0.67, but only moderate genetic correlations existed between FW12 and W6 (0.39) and between FW12 and W12 (0.49). The genetic correlation between FW6 and FW12 was very high (0.95), but the corresponding phenotypic correlation was much lower (0.28). Heritability estimates for all traits were at least 0.15, indicating that there is potential for their improvement by selection. The moderate to high positive genetic correlations between fleece weights and body weights at 6 and 12 months of age suggest that some of the genetic factors that influence animal growth also influence wool growth. Thus selection to improve the body weights or fleece weights at 6 months of age will also result in genetic improvement of fleece weights at subsequent stages of growth.  相似文献   

Direct and maternal (co)variance components and heritability estimates for body weights in Chokla sheep   总被引：2，自引：0，他引：2  

B.P. Kushwaha  A. Mandal  A.L. Arora  R. Kumar  S. Kumar  & D.R. Notter 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(4):278-287

Estimates of (co)variance components were obtained for weights at birth, weaning and 6, 9 and 12 months of age in Chokla sheep maintained at the Central Sheep and Wool Research Institute, Avikanagar, Rajasthan, India, over a period of 21 years (1980–2000). Records of 2030 lambs descended from 150 rams and 616 ewes were used in the study. Analyses were carried out by restricted maximum likelihood (REML) fitting an animal model and ignoring or including maternal genetic or permanent environmental effects. Six different animal models were fitted for all traits. The best model was chosen after testing the improvement of the log-likelihood values. Direct heritability estimates were inflated substantially for all traits when maternal effects were ignored. Heritability estimates for weight at birth, weaning and 6, 9 and 12 months of age were 0.20, 0.18, 0.16, 0.22 and 0.23, respectively in the best models. Additive maternal and maternal permanent environmental effects were both significant at birth, accounting for 9% and 12% of phenotypic variance, respectively, but the source of maternal effects (additive versus permanent environmental) at later ages could not be clearly identified. The estimated repeatabilities across years of ewe effects on lamb body weights were 0.26, 0.14, 0.12, 0.13, and 0.15 at birth, weaning, 6, 9 and 12 months of age, respectively. These results indicate that modest rates of genetic progress are possible for all weights.  相似文献   

Landscape and land use effects on soil resources in a Himalayan watershed     

Debashis Mandal  Ratan SinghS.K. Dhyani  B.L. Dhyani 《CATENA》2010

Sustainable land management decisions at all scales require solid, science-based information. Soil quality assessment can provide this regarding soil physical, chemical, and biological characteristics and the ability to provide ecosystem and societal services. Our objective was to make a regional assessment of soils in the Garhwal Himalayas to determine their ability to perform various functions and respond to external influences. Five functional categories were assessed using 13 soil parameters focused on ecological sustainability. Human land use effects on soils were referenced to natural woodlands at each landscape position. Within upper-slope regions, flora and fauna habitat, moisture retention, organic matter and nutrient cycling, air and water infiltration and resistance to erosion were decreased 35, 27, 24, 24, and 9%, respectively. At mid-slope positions the order and magnitude of decrease were organic matter and nutrient cycling, flora and fauna habitat, and moisture retention (26, 22, and 16%, respectively). Changes within the valley were lowest, averaging − 3% for flora and fauna habitat and − 13% for organic matter and nutrient cycling. We conclude that the minimum data set (MDS) used provided a representative assessment of soil quality and could serve as a basis for assessment in similar tropical watersheds.  相似文献   

Allelopathic activity of root exudates from Leonurus sibiricus L. (Raktodrone)     

Suparna Mandal 《Weed Biology and Management》2001,1(3):170-175

Root exudates (RE) of Leonurus sibiricus L. show the stimulatory effect of a bioassay on rice, wheat and mustard. Root exudate shows concentration-dependent activity. A stock solution (one seedling in 200 mL of 0.1% Knop's solution for 4 days) is denoted as (1). A 10-fold higher concentration (10) was made by using a rotary vacuum evaporator; for example, 100 mL stock solution was reduced to 10 mL. For bioassay, (25), (50), (75) and (100)-fold concentrations have been used. The stimulatory effect increases with concentration (peak at 10), decreases thereafter, and at (50) (75) and (100), the effect is inhibitory (almost 100% at 75 and 100). Paper chromatography and staining suggest the presence of phenolics including caffeic acid in RE. Caffeic acid also shows the same concentration-dependent activity on rice seeds. An ether extract of acid hydrolyzed leaves shows a number of phenolics on thin layer chromatography. Among these phenolics, three are common with RE. One highly fluorescent band occurs in a much larger amount (both RE and acid hydrolyzed leaf extract), and coincides with standard caffeic acid. On ultraviolet spectrometer analysis after elution, the putative caffeic acid compound shows two characteristic peaks similar to that of caffeic acid at 277 and 231 nm, respectively. Gas liquid chromatography retention time of both standard caffeic acid and the fluorescent spot is the same.  相似文献   

Variations in the Length of the Y Chromosome and the Seminal Attributes of Karan Fries Bulls     

Mandal A  Sharma A 《Veterinary research communications》2003,27(7):567-575

Fresh semen and blood samples from 20 Karan Fries bulls (4–6 years of age), maintained at the Artificial Breeding Complex of the National Dairy Research Institute, Karnal, were collected for one year. All the bulls had 60 chromosomes, comprising 58 acrocentric autosomes and 2 sex chromosomes, with X as the larger and Y as the smaller submetacentric. The mean lengths of Y_p and Y_q; the total length of the Y chromosome and the length ratio were 1.10±0.01 m, 1.83±0.02 m, 2.92±0.02 m and 62.46%±0.18%, respectively. Analysis of the length measurements of the the Y chromosomes in Karan Fries bulls showed that all the measurements, viz., the short arm of the Y chromosome, the long arm of the Y chromosome, the total length of the Y chromosome and the variation in length of Y chromosome, varied significantly among bulls. All the seminal parameters, the volume of semen, mass activity, initial motility, concentration, live sperm count and the total abnormal sperm count, were significantly affected by bulls, whereas season had a significant effect on all the seminal parameters except the total abnormal sperm count. No significant relationship between the ratio of the long arm to the total length of the Y chromosome and seminal attributes was observed.  相似文献   

Effect of in ovo threonine supplementation on early growth,immunological responses and digestive enzyme activities in broiler chickens     

Dr M.M. Kadam  S.K. Bhanja  A.B. Mandal  R. Thakur  P. Vasan  A. Bhattacharyya 《British poultry science》2008,49(6):736-741

1.?The effects of injecting threonine in ovo on early growth, some immunological responses and the activity of digestive enzymes of broiler chicks were investigated. Fertile eggs were distributed into 6 groups, each of 60. These were: untreated control, sham control, 10, 20, 30 or 40 mg threonine. Threonine was dissolved in 0·5 ml sterile saline and inoculated into the yolk sac of the 14-d-old embryo through the narrow end of the egg.

2.?The ratio of chick to egg weight was 1·6% higher in the group given 30 mg threonine and at 28 d of age chicks receiving threonine were 29 to 79 g heavier than untreated controls.

3.?Food conversion ratio until 7 d after hatching was improved in those chicks receiving 10, 20 or 40 mg threonine but there was no significant effect on the activities of amylase, pepsin or trypsin.

4.?The humoral response to sheep red blood cells was significantly greater in those groups receiving 10, 20 or 30 mg threonine supplementation than in untreated controls.

5.?The response to phytohaemagglutinin-P, a measure of the cell-mediated immune response, was not affected, however.

6.?It is concluded that injections of 20 to 30 mg threonine into yolk sac can improve post-hatching growth and humoral responses of broiler chicks.  相似文献