Effect of sub-lethal nitrite on selected haematological parameters in fingerling Catla catla (Hamilton)   总被引：1，自引：0，他引：1  

Pratap Chandra Das  Subanna Ayyappan  Joy Krushna Jena  & Basanta Kumar Das 《Aquaculture Research》2004,35(9):874-880

A sub‐lethal nitrite toxicity trial was conducted using static conditions for a period of 96 h with fingerlings of Catla catla (21.4±3.6 g). Fingerlings were exposed to five concentrations of nitrite, that is, 1, 2, 4, 8 and 10.4 mg L^?1 and a nitrite‐free control to study changes in haematological parameters. Nitrite caused an increase in immature erythrocyte population (7–24%) in lower concentrations (0–4 mg L^?1) at 6 h while they were absent in higher concentrations. The total erythrocyte count was reduced at 6 h followed by an increase at 12 h with further reduction up to 96 h in all concentrations of nitrite. The 96‐h exposure resulted in 21.2–31.8% reduction in erythrocyte population in 1–10.4 mg L^?1 nitrite. The haemoglobin content decreased progressively with increasing nitrite concentrations as well as exposure periods. Total leukocyte count decreased initially at 6 h in all treatments followed by an increase after 12 h, signifying development of a protective response of the body to nitrite stress. Blood glucose decreased initially up to 24 h followed by an increase through 96 h. Serum protein level decreased continuously with increasing exposure period. The study revealed that exposure to nitrite caused changes in almost all the haematological parameters in the fingerlings depending on the concentration as well as exposure period. Nitrite being one of the important inorganic nutrients often recorded at higher levels in intensively cultured ponds, the present study highlights its adverse impact on fish and stressed the need for the management of this nutrient in culture ponds.  相似文献   

Comparative changes in water quality and role of pond soil after application of different levels of organic and inorganic inputs   总被引：2，自引：0，他引：2  

Pratap Chandra Das  Subanna Ayyappan  & Joykrushna Jena 《Aquaculture Research》2005,36(8):785-798

Changes in water parameters were studied in a yard experiment for 7 weeks after application of cow dung at 20, 50 and 100 t ha^?1, poultry manure at 4, 10 and 20 t ha^?1, feed mixture (groundnut oil cake and rice bran at 1:1) at 10, 20 and 30 t ha^?1 and inorganic fertilizers at 100 kg urea+50 kg single super phosphate (SSP) ha^?1, twice this dose (2x ha^?1) and thrice this dose (3x ha^?1). To study the role of soil in the mineralization process, each treatment was divided into two groups – one with and the other without soil substrate. Higher degree of changes in water parameters was observed at higher input levels. Both organic amendment and inorganic fertilization caused significant reduction (P<0.05) in dissolved oxygen and increase in free CO₂, dissolved organic matter, total ammonia, nitrite, nitrate and phosphorus contents of water. Organic inputs significantly decreased (P<0.05) water pH and increased total alkalinity and hardness. In contrast, inorganic fertilization caused a significant increase in pH; alkalinity and hardness increased significantly in the presence of soil, but reduced in its absence. In organic input, presence of soil substrate caused significantly lower value of pH, dissolved oxygen, dissolved organic matter and phosphate‐phosphorus and significantly higher free CO₂, alkalinity, hardness, ammonia, nitrite and nitrate contents, compared with those in the absence of soil, revealing enhanced microbial mineralization in the presence of soil.  相似文献   

Arsenic in irrigated water,soil, and rice: perspective of the cropping seasons     

Anirban Biswas  Saroni Biswas  Subhas Chandra Santra 《Paddy and Water Environment》2014,12(4):407-412

Arsenic contamination of shallow groundwater and related health problems are threats for the millions in endemic regions of West Bengal. Contamination of rice grain creates the food chain pathway of mineral arsenic besides drinking water contamination. Present study concentrated on association of arsenic concentration in irrigated water, paddy field soil and rice with the cropping seasons. Irrigated ground water arsenic concentration decreased significantly (p = 0.007) from summer (median 0.42 mg l^?1) to winter (median 0.35 mg l^?1). Carried over effect created significant decrease (p = 0.03) of paddy field soil arsenic concentration from summer (median 8.35 mg kg^?1) to winter (median 6.17 mg kg^?1). Seasonal variation was observed in rice straw (p = 0.03) but not in husk (p = 0.91). Arsenic concentration decreased significantly (p = 0.05) in the rice grains collected in winter season (median 0.23 mg kg^?1) than the samples collected in the summer season (median 0.30 mg kg^?1). In conclusion, seasonal effects need to be considered in case of human health risk assessment from arsenic consumption.  相似文献   

Composite wound dressing for drug release     

Roli Purwar  Poonam Rajput  Chandra Mohan Srivastava 《Fibers and Polymers》2014,15(7):1422-1428

Present study is focused on the preparation of two layers composite wound dressing for drug release. The outer layer is made of hydrogel which contains of drug and the core layer is made of fabric. The two layers structure of composite dressing is formed by grafting of polyacrylamide-co-acrylic acid hydrogel on cotton fabric using ammonium per sulphate (APS) as chemical initiator and polyethylene glycol (PEG) as crosslinker. The major factors affecting graft copolymerization of hydrogel on cotton fabric are optimized by varying concentration of monomers & initiator, reaction temperature and addition time of crosslinker. Maximum grafting of hydrogel is obtained at 5 % (w/v) APS and 15 % acrylamide/acrylic acid (1:1 w/w ratio) concentration. The FTIR spectra of composite dressing shows characteristics peak of acrylic acid and acrylamide. The composite wound dressing material is loaded with model drug bovine serum albumin (BSA) and drug release behaviour is studied at different pH. The dressing shows drug release in different pH with maximum release of drug in acidic medium.  相似文献   

A short review on sugarcane: its domestication,molecular manipulations and future perspectives     

Dinesh Babu  Kandhalu Sagadevan  Janakiraman  Vardhana  Palaniswamy  Harunipriya  Kasirajan  Lakshmi  Gomathi  Raju  Ramkumar  Thakku R. 《Genetic Resources and Crop Evolution》2022,69(8):2623-2643

Sugarcane (Saccharum spp.) is a special crop plant that underwent anthropogenic evolution from a wild grass species to an important food, fodder, and energy crop. Unlike any other grass species which were selected for their kernels, sugarcane was selected for its high stem sucrose accumulation. Flowering in sugarcane is not favored since flowering diverts the stored sugar resources for the reproductive and developmental energy needs. Cultivars are vegetatively propagated and sugarcane breeding is still essentially focused on conventional methods, since the knowledge of sugarcane genetics has lagged that of other major crops. Cultivar improvement has been extremely challenging due to its polyploidy and aneuploidy nature derived from a few interspecific hybridizations between Saccharum officinarum and Saccharum spontaneum, revealing the coexistence of two distinct genome organization modes in the modern variety. Alongside implementation of modern agricultural techniques, generation of hybrid clones, transgenics and genome edited events will help to meet the ever-growing bioenergy needs. Additionally, there are two common biotechnological approaches to improve plant stress tolerance, which includes marker-assisted selection (MAS) and genetic transformation. During the past two decades, the use of molecular approaches has contributed greatly to a better understanding of the genetic and biochemical basis of plant stress-tolerance and in some cases, it led to the development of plants with enhanced tolerance to abiotic stress. Hence, this review mainly intends on the events that shaped the sugarcane as what it is now and what challenges ahead and measures taken to further improve its yield, production and maximize utilization to beat the growing demands.

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Allelopathic Effect of Eucalyptus globulus Labill. on Cyperus rotundus L. and Cynodon dactylon L. Pers.     

R. Chandra Babu  O. S. Kandasamy 《Journal of Agronomy and Crop Science》1997,179(2):123-126

The allelopathic potential of Eucalyptus globulus Labill. (gum tree) fresh and dried leaf leachates was studied using two perennial weeds, viz. purple nutsedge (Cyperus rotundus L.) and bermuda grass (Cynodon dactylon L. Pers) as test weeds. Aqueous leachate of fresh leaves of eucalyptus significantly suppressed the establishment of vegetative propagules and early seedling growth of the weeds. Leachate of fresh leaf cuttings had growth inhibitory effect on bermuda grass but showed growth promotion effect on purple nutsedge. Similarly the leachate of dried leaves of eucalyptus had differential influence on the growth of the two weeds. There is a possibility to harness the allelochemicals of eucalyptus leaves as herbicides for the management of these perennial weeds.  相似文献   

A unique introgression from Moricandia arvensis confers male fertility upon two different cytoplasmic male-sterile lines of Brassica juncea     

S. R. Bhat    S. Prakash    P. B. Kirti    V. Dinesh  Kumar V. L. Chopra 《Plant Breeding》2005,124(2):117-120

A Brassica juncea line carrying an introgression from Moricandia arvensis restored male fertility to two cytoplasmic male‐sterile (CMS) B. juncea lines carrying either M. arvensis or Diplotaxis catholica cytoplasm. Genetics of fertility restoration was studied in the F₁, F₂, F₃ and backcross generations of the cross between CMS and fertility‐restorer lines. No male‐sterile plants were found in F1‐F₃ generations of the cross between CMS [M. arvensis] B. juncea and the restorer. However, a 1: 1 segregation for male sterility and fertility was observed when the F1 was pollinated with non‐restorer pollen from a euplasmic line. These results clearly show that restoration is mono‐genic and gametophytic. In CMS lines carrying D. catholica cytoplasm, the restorer conferred male fertility to the F1 and showed 3: 1 and 1: 1 segregations for male fertility and sterility in F₂ and BC1 generations, respectively, indicating a monogenic, sporophytic mode of fertility restoration. The results were also supported by pollen stainability in the F1 which was about 65% in M. arvensis‐based CMS and >90% in D. catholica‐based CMS. The above results are discussed in the light of previous molecular studies which showed association between CMS and atpA in both systems.  相似文献   

The Political Crisis and the Manufacturing Sector in Fiji     

Rajesh Chandra 《Asia Pacific viewpoint》1989,30(2):163-178

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Influence of chloride and sulphate ions on soil enzymes   总被引：1，自引：0，他引：1  

R. Dinesh    G. Ramanathan  Harjit  Singh 《Journal of Agronomy and Crop Science》1995,175(2):129-133

Ammonium chloride (AC) and ammonium sulphate (AS) are commonly used nitrogen fertilizers. But the effect of chloride and sulphate ions from these fertilizers on soil enzyme activity has received scant attention. Hence, we conducted a pot culture study to assess the influence of chloride (as AC) and sulphate (as AS) on the activities of urease, amidase, phosphatase and dehydrogenase in soil using rice as the test crop. Chloride and sulphate levels were fixed at 132, 264 and 396 kg ha⁻¹ respectively. Controls were also performed. The enzymes were assayed at three stages of the crop growth viz., active tillering, panicle initiation and harvest.
The enzyme activities decreased with increasing chloride and sulphate levels; however, the degree of inhibition varied among the enzymes assayed and the nature and amounts of salts added. The inhibition may be due to the specific effects of chloride and sulphate ions on microbial growth and subsequent enzyme synthesis, osmotic desiccation leading to microbial cell lysis, and a salting-out effect modifying the ionic conformation of the active site of the enzyme protein.  相似文献   

Effect of kilning on the antioxidant and pro-oxidant activities of pale malts     

Woffenden HM  Ames JM  Chandra S  Anese M  Nicoli MC 《Journal of agricultural and food chemistry》2002,50(17):4925-4933

Pale malts were prepared using standard and rapid kilning regimes that differed in the temperature and moisture profiles in the kiln. Samples were taken over the last 9 h of kilning, that is, at 18, 20, 22, 25, and 27 h. Antioxidant activity, assessed by redox potential, scavenging of the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS*+), and ferric reducing/antioxidant power (FRAP), increased at moisture levels below 6.7% for both regimes. The 27 h malt exposed to the rapid regime (moisture content of 4.8%) had a higher activity than the 27 h standard regime sample (moisture content of 4.8%). None of the malts scavenged oxygen. Pro-oxidant activity profiles were different for the malts obtained using each regime and, at 27 h, the rapid procedure gave malt with higher activity. Levels of (+)-catechin and ferulic acid (the most abundant phenolic compounds identified) generally increased as the moisture content of malt fell below 6.7%. Differences in antioxidant and pro-oxidant activities of the 27 h malts are partly attributed to the Maillard reaction, as evidenced by lower L* and higher b* values and higher levels of Maillard-derived flavor compounds, in the sample obtained by the rapid procedure. Levels of lipid-derived flavor compounds were significantly higher after 27 h of kilning using the rapid procedure.  相似文献