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Response of Nitrate-Hardened Brassica Seeds to
Heavy Metal HgCl2 Stress
--Yaksha Singh,
--Varsha Chaturvedi,
--C P Malik
Various industrial and other anthropogenic activities have considerably increased the levels of heavy metals in the
environment. These metals restrict the plant growth and pose a threat to human life. Experiments were conducted to assess the effects of
heavy metals on various physiological parameters in
Brassica juncea cvs. Further, whether hardening treatment with nitrate salt
mitigates some physiological parameters under controlled and heavy metal
HgCl2 treatment. The results show the percentage
germination progressively declined with increasing concentrations of heavy metal. However, in Hardened Seeds (HS) and Non-Hardened
Seeds (NHS) germination was 100%. At lower concentrations of heavy metals, i.e., 0.5-1 mM, germination was reduced and at 10
mM concentration, seeds failed to germinate. HS showed enhanced germination percentage over NHS in both cvs. With
increasing concentration of heavymetals the length of root and shoot seedlings progressively declined in both HS and NHS. In HS,
deleterious effect of HgCl2 was mitigated. Dry matter of seedlings of HS in comparison to NHS control was more in both the cvs. There
was a considerable decrease in the total chlorophyll content with metal treatment. Metal-stressed seedlings retained less
water content and showed a greater damage to membranes as Electrolyte Leakage (EL) and proline accumulated in seedlings in
response to heavy metal treatment. Relatively, HS showed increase in the proline content compared to NHS. The present
investigation suggests the nitrate pretreatment possibly induces withstanding capacity in
Brassica seedlings to grow in soils affected by
heavy metal mercury. The data are compared in the two cvs, i.e., P Bold and
Vasundhra.
© 2010 IUP. All Rights Reserved.
Effect of Environmental Factors on Chitinase Production
by Serratia marcescens GG5
--Gursharan Singh
,-- Aditya Bhalla,
--Gurinder Singh Hoondal
Chitinase production was observed under varying environmental conditions, i.e., pH (4-9), temperature (25-37 ºC) and
agitation (150 and 200 rpm). Optimum pH, temperature and agitation for maximum enzyme production were 7.0-8.0, 30 ºC and 150
rpm, respectively. NaCl inclusion at 0.5% enhanced chitinase production by 35% in chitin minimal medium.
Serratia marcescens GG5 inhibited the growth of
Fusarium oxysporum, Rhizopus nigricans
and Mucor rouxi on sabourouds agar medium
supplemented with the 0.1% of swollen chitin.
© 2010 IUP. All Rights Reserved.
Allelopathic Effect of Croton bonplandianum
Baill. on Mature Growth Phases of Wheat and Mustard
--Eva Sarkar,
--Pampa Chakraborty
Based on the minimum duration of exposure, the effect of aqueous plant extract of
Croton bonplandianum on seed germination and seedling growth of
Triticum aestivum and Brassica campestris
was established. Allelopathic activity of the extract
increased with increasing duration of presoaking, being more in wheat than in mustard. There is an increasing evidence that
several allelopathic compounds inhibit the growth of affected plants through a direct or indirect effect on the rate of
photosynthesis. Chlorophyll content and Hill activity of both the crops decreased upon treatment with the inhibitor solution. Soil dressing
with leaf-extract seriously affected the target crops. Plant height, root length, number of leaves as well as fruit output and fresh
weight are the parameters that were affected more.
© 2010 IUP. All Rights Reserved.
Rhamnolipid Production
by Pseudomonas aeruginosa JC2 in Different
N-Heterocylic Aromatic Hydrocarbons
--Aparna P,
--Sasikala Ch,
--Ramana Ch V
An isolate from garden soil, Pseudomonas
aeruginosa JC2 produced rhamnolipid whose structure was determined by
mass spectral analysis and was found to be L-rhamanosyl
L-rhamnolsyl-b-hydroxydecanoyl-b-hydroxydecanoate. The concentration
of rhamnolipid produced was checked in the presence of various nitrogen containing heterocyclic aromatic hydrocarbons (1 mM)
with glucose (1%) as carbon source. Pyrazine-2-carboxylate served as best source as it contributed to the production of 240
mg/L concentration of rhamnolipid when compared with other compounds. Highest amounts of rhamnolipid (360 mg/L) were
produced when 6.4 mM concentration of pyrazine-2-carboxylate was used.
© 2010 IUP. All Rights Reserved.
Effect of Drying on the Essential Oil
and the Mineral Contents of Basil
(Ocimum basilicum L.)
--G L Pachkore,
--S K Markandeya
The present study deals with the effect of drying on mineral and essential oil content of
Ocimum basilicum. The characteristics of basil
(Ocimum basilicum L.) were studied at 50
°C under sun drying and oven drying. The effect of various drying methods
on the essential oil and mineral content, such as oven drying and the wire basket sun drying basil was compared. Oven
drying resulted in an increase of drying rate and shorter drying time. Basil can be oven-dried to 11.31% moisture content after 15 h
at 50 °C and sun-dried to 23.79% content after 28 h. The mineral content of oven-dried material was higher than sun-dried. Ca,
K, P contents were determined as minerals in both oven- and sun-dried material. The essential oil content of sun-dried material
was higher than oven-dried.
© 2010 IUP. All Rights Reserved.
Benthic Faunal Diversity
in Muthupettai Mangroves
on Southeast Coast of India
--B Thilagavathi,
--K Samidurai,
--A
Saravanakumar
A study was carried out in the Muthupettai mangrove area and Open Sea to evaluate the diversity of macro benthic organisms
and its distribution with respect to hydrographical parameters. During the present study, the water temperature varied from
23.5° to 31.8 °C, salinity fluctuated from 24 to 34. The pH level varied from 7.4 to 8.3, dissolved oxygen concentration varied from
3.36 to 5.33. The texture of the soil in open sea and Sethukuda recorded clay, silt, sand. A total of 39 species of macro benthic
fauna were recorded. Among them, 17 species belonged to polychaetes, 10 species to crustaceans, 10 species to molluscs,
single species to sipunculida, fish larvae and hermit crab. The macro fauna population density varied from 17 to 409 individuals/sq
m, respectively. The macro faunal maximum density was 409
± 17 No/m2 and minimum density was 91
± 30 No/m2.
© 2010 IUP. All Rights Reserved.
Newcastle Disease and Infectious Bursal Diseases
are Threat to Village Chicken Production in Two Districts
of Amhara National Regional State, Northwest Ethiopia
--Hailu Mazengia,
--S B Tilahun,
--T Negash
Newcastle Disease (ND) and Infectious Bursal Disease (IBD) are the major diseases affecting poultry production.
Serological studies using Haemagglutination-Inhibition (HI) for ND and Agar gel immunodiffusion (AGID) for IBD were conducted
to determine the prevalence and risk factors associated with ND and IBD in chickens owned by 775 households in two districts
(n = 392 for Bahir Dar and n = 383 for Farta) of Amhara national regional state, Northwest Ethiopia. The overall
seroprevalence of ND in non-vaccinated chickens was 64.10%. The highest seroprevalence of ND (34.40%) was recorded in the households
of Farta district. In multivariate logistic regression analysis breed type, methods of disposal of dead chickens and status of
hygiene were found to be the actual risk factors associated with the occurrence of ND. The study also reports the status and risk
factors associated with IBD. The overall seroprevalence of IBD in this study was 51.10%. Higher seroprevalence of
IBD was recorded in Bahir Dar (29.40%) than in Farta (21.70%) district. Similarly, in the multivariate logistic regression analysis study districts,
breed type, source of parent flock, method of disposal of dead birds and status of hygiene were found to be highly associated with
the occurrence of IBD.
© 2010 IUP. All Rights Reserved.
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