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| ARPN Journal of Agricultural and Biological
Science March 2011
| Vol. 6 No. 3 |
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Title: |
Management of bacterial wilt of Brinjal by P. fluorescens
based bio-formulation |
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Author (s): |
Gargi
Chakravarty and Mohan Chandra Kalita |
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Abstract: |
An experiment was conducted in
the laboratory and farm of the Department of Biotechnology, Gauhati University to explore the potentiality of an
indigenous strain of Pseudomonas fluorescens as a
biocontrol agent in the management of bacterial wilt disease
of Brinjal under local conditions. Different organic
materials were evaluated for their potential as substrate
carriers in the formulation of P. fluorescens based
biopesticide. Vermicompost and farmyard manure were found to
support significantly longer shelf life of the biocontrol
bacteria. Carboxy methyl cellulose and substrate carrier
based formulations of P. fluorescens were applied by
different methods in pot and field experiments to study
their effectiveness in the control of bacterial wilt of
Brinjal. CVPf formulation and seed + root + soil method of
application performed significantly better than others
providing 83.33% control of bacterial wilt of Brinjal in
field experiment conducted by Completely Randomized Block
Design. CVPf treated brinjal plants also recorded
significantly higher yield and yield attributes than other
formulation treated Brinjal crops. Effective management of
bacterial wilt of Brinjal and improvement of yield and yield
attributes by the P. fluorescens based organic
formulation under local conditions signifies its
potentiality and scope as a PGPR.
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Title: |
Influence
of seed priming on physiological performance of fresh and
aged seeds of maize hybrid [COH(M) 5] and its parental
lines |
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Author (s): |
Sathish
S., S. Sundareswaran and N. Ganesan |
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Abstract: |
Laboratory and field studies
were conducted to evaluate the influence of seed priming on
physiological parameters of fresh and aged seeds of maize
hybrid [COH(M) 5] and its parental lines UMI 285 (female)
and UMI 61 (male). Seeds were soaked in water, 1% KH2PO4, 3%
KNO3 and 2 % CaCl2 solution for 6 hours.
The results revealed that seed priming with 1% KH2PO4
for 6 hours showed an increased physiological performance in
fresh and aged seeds of UMI 285, UMI 61 and [COH(M) 5]. The
increased physiological performance was observed in terms of
increased germination percentage, shoot length, root length,
dry matter production and vigour index; accompanied with
earlier germination in terms of days to 50% germination and
days to maximum germination. Increased field emergence
potential was also observed in the seeds primed with 1% KH2PO4
for 6 hours. However, more pronounced effect of seed priming
with 1% KH2PO4 for 6 hours was observed in
aged seeds than in fresh seeds. |
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Title: |
Effects
of growth retardants, paclobutrazol (PBZ) and prohexadione-Ca
on floral induction of regular bearing mango (Mangifera
indica L.) cultivars during off-season |
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Author (s): |
Adil O.
S. Abdel Rahim, Osman M. Elamin and Fritz K. Bangerth |
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Abstract: |
Off season (out of season)
floral induction will extend the season of mango production
and increase farmers’ income. Accordingly, the aims of this
study were to investigate the roles of two gibberellins
biosynthesis inhibitors, paclobutrazol and prohexadione-Ca;
on off season flowering of regular bearing mango cultivars
as well as to examine the possible associated hormonal
changes. Paclobutrazol experiment was conducted on two
orchards while prohexadione-Ca experiment was conducted on
one orchard; all are located under tropics of central Sudan
(Latitude 14° 23’, Longitude 29° 33’). Our results
implicated the positive role of paclobutrazol on floral
induction of the two regular bearing mango cultivars, Baladi
AbuZaid and Baladi Burai during off season. Similarly,
prohexadione-Ca was effective in advancing off season
flowering of the regular bearing mango cultivar, Baladi
Elriah. The levels of cytokinins (zeatin (z) +
zeatin-riboside (zr) and isopentenyl Adenine (i-Ade) +
isopentenyl Adenosine (i-Ado) were generally increased
during the floral induction period, while those of
gibberellins and auxin (IAA) were decreased during the same
period. Our results might implicated the possibility of
inducing out of season flowering and thus extending the
season of mango harvest under central Sudan conditions. |
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Title: |
Metribuzin mobility in soil column as affected by
environmental and physico-chemical parameters in Mumias Sugarcane
Zone, Kenya |
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Author (s): |
S. C.
Lagat, J. O. Lalah, C. O. Kowenje and Z. M. Getenga |
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Abstract: |
The physico-chemical parameters of soil,
influences the soil solution characteristics and that may
affect the sorption of soil applied herbicides. The present
investigation reports the influence of physico-chemical
parameters sorption and leaching of metribuzin, a triazine
herbicide. The Kf (Freundlich adsorption
coefficient) values of metribuzin were 0.024 which suggests
that sorption as a function of herbicide concentrations and
(1/n) value of 1.240 reflecting the degree of sorption of
the herbicide. For leaching the amounts of metribuzin leached
were 89.83% of applied quantity. This is due to effects of
various physicochemical factors and climatic conditions in
tropical soils. The study concludes that less than 10.17% of
applied metribuzin remains in the soil. However, from
agricultural point of view, the amounts are trivial, but
from environmental (including potential ground water
contamination) point of view, small residues are important
factors to consider. |
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Title: |
An
assessment of the physico-chemical properties to study the
pollution potential of Ujjani reservoir, Solapur District,
India |
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Author (s): |
R. R. Sangpal, U. D.
Kulkarni and Y. M. Nandurkar |
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Abstract: |
Sampling of the physico-chemical
factors from 20 stations on the surface water of Ujjani dam
(Yeshwantsagar reservoir), Solapur district, India. Water of Ujjani dam was studied for pollution by determining various
water quality parameters, for the two season’s viz.,
pre-monsoon and post-monsoon. The dam water is subjected to
sever domestic and industrial pollution. The aim’s been to
determine the water quality, productivity, assess nature or
mans impact and industrial pollution on the physico-chemistry
of the reservoir water. Our findings highlighted the
deterioration of water quality in the dam due to
industrialization and urbanization. Temperature ranged
between 200c to 320c. The pH range is
7.17 to 9.20. The organic pollution is sever as indicated by
DO 2.21 to 7.09 mg/L and BOD 0.4 to 3.89 mg/L and also
highest value of COD ranging between 9.18 to as high as 46.4
mg/L indicates industrial pollution. |
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Title: |
Analysis
of heterosis over environments in silkworm (Bombyx mori
L.) |
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Author (s): |
S. Nirmal
Kumar, D. P. Prakash Murthy and S. M. Moorthy |
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Abstract: |
The magnitude of heterosis
over mid-parent and better parent were calculated in fifty
bivoltine hybrids derived from five oval type and five
dumbbell type bivoltine genotypes of silkworm, Bombyx
mori L for eight important traits under varying
environmental conditions. The expression of both relative
heterosis and heterobeltiosis was higher in summer (8.97 and
6.71%), followed by rainy (5.87 and 3.42%) and winter (2.13
and 0.03%). In summer, pupation rate, cocoon weight, shell
weight and filament length exhibited higher heterosis for
both relative heterosis and heterobeltiosis and total larval
period in winter. Negative heterosis was observed for
neatness. Among the characters pupation% exhibited higher
heterosis (14.56%), followed by shell weight (11.74%),
filament length (8.91%) and cocoon weight (6.49). Many
hybrids displayed conspicuous heterosis for most of the
characters. There was differential behaviour of various
hybrids in different environments for the expression of
heterosis. Estimates of heterosis computed revealed
significant reciprocal effect for most of the traits but no
consistent pattern was found across hybrids. All straight
and reciprocal crosses exhibited significant positive
heterosis and heterobeltiosis for pupation rate in all three
environments. Other characters did not show such uniform
trend. The crosses which involved CSR4, CSR17, CSR18,
CSR19, KA and NB4D2 as one of the parents exhibited
favourable heterosis and crosses (Straight and reciprocals)
viz., CSR17 x CSR4, CSR18 x CSR19, CSR4 x KA and CSR17 x
19 showed desirable heterosis for most of the characters.
The study showed the potential of commercial exploitation of
heterosis as well as the potential of isolating pure lines
among the progenies of heterotic F1s
for improvement of yield potential in silkworm. |
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Title: |
Social
capital and microcredit effects on poverty among the rural
households in south west states, Nigeria |
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Author (s): |
Balogun
O. L., S. A. Yusuf, B. T. Omonona and V. O. Okoruwa |
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Abstract: |
Nigeria represents one of the
many paradoxes of development in which case the nation is
rich but her people are poor. This
study examines the influence of social capital and
microcredit on poverty status of rural households in South
western, Nigeria. A multistage sampling was employed for the
study. Ekiti and Osun states were randomly selected from the
six states in South-western Nigeria. This was followed by
random selection of two Local Government Areas from each
senatorial district of the states. Thirty microcredit groups
were randomly selected from each of the selected Local
Government Areas based on probability proportionate to the
size of the microcredit group. Lastly, 399 respondents were
randomly selected from the microcredit groups. Data were
collected using structured questionnaire. The data were
analyzed using descriptive statistics, Foster-Greer-Thorbecke
(FGT) weighted poverty indices and Tobit regression. Mean
age and household size were 41.3 ± 11.4 years and 6.0± 2.2, respectively. At a poverty line of N2, 930.90, 52.1%
of the households were poor. Household size and age squared
increased poverty by 0.016 and 1.0 X10-4 while
asset value, friends/family credit and decision making index
reduced poverty by 0.005, 5.99X10-7 and
0.225, respectively. Social
capital significantly influenced the amount of credit
available from different sources. Household size and age
squared of household head increased poverty while credit
from friends and relatives, large asset of household and
active participation in decision making process (a component
of social capital) reduced poverty. |
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Title: |
Urea
hydrolysis in saturated loam soil |
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Author(s): |
M.
Ramananda Bhat, D. V. R. Murthy and M. B. Saidutta |
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Abstract: |
In order to evaluate the
extent of loss of applied fertilizer urea due to hydrolysis
catalyzed by the enzyme urease and assist in the development
of mathematical model for the spread of urea from the source
of application, it is necessary to conduct hydrolysis
studies in wet soils. Agricultural loam soil, with 13% clay
content from west coast region of India, was taken up for
this purpose. Maximum particle size of the soil was
restricted to 2 mm in the study. Batch trials were conducted
with different urea concentrations maintained in the soil
which was previously incubated at 270C for 48
hours under saturated condition. Evolved gases were allowed
to escape to prevent build up of
alkali and the subsequent deactivation of the enzyme at high
pH. Urea estimation was carried out by colorimetric method.
Results indicate that for soil solution urea concentration
up to 43.6 mg/mL, the rate of hydrolysis increased with
increasing initial urea concentration. For concentrations in
the range of 43.6 to 243 mg/mL, rate of hydrolysis
decreased with increasing
initial urea concentration. The urease induced hydrolysis
was completely deactivated at concentration of 305 mg/mL and
beyond due to the substrate induced inhibition. The
experimental data could be fitted to a substrate inhibition
model. |
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Title: |
The
effects of benzyladenine and meta-topolin on in vitro shoot
regeneration of sweet orange |
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Author (s): |
Randall
P. Niedz and Terence J. Evens |
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Abstract: |
The effects of
6-benzyladeninepurine (BA) and meta-topolin (mT) on
shoot quality, numbers of explants that produce buds and/or
shoots, and the number of shoots greater than 2 mm from
‘Hamlin’ sweet orange (Citrus sinensis L.) Osbeck)
epicotyl explants were determined. The experiment was
designed as a mixture-amount. BA and mT were varied
proportionally from 0 BA: 1 mT to 1 BA: 0 mT
and the total concentration of cytokinins varied from 1 to
50 μM. The polynomial response models developed for each of
the three measured responses were highly significant (p <
0.0001) and allowed the accurate determination of the
proportional and amount effects of these two cytokinins
Proportional effects were either not detected (number of
explants w/ shoots/buds and number shoots > 2 mm) or were
statistically significant but had minimal biological effect
(overall quality). Total concentration of cytokinin (BA or
mT) in the medium was the primary determinant for all
three responses. |
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Title: |
Non-linear modeling of soil sinkage by multiple loadings
using the finite element method |
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Author (s): |
Majid
Rashidi and Mohammad Gholami |
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Abstract: |
It is usual practice to use
the same wheel tractor for different agricultural field
operations. As the agricultural soil is exposed to multiple
loadings of the same magnitude in this situation, it is
valuable to predict soil sinkage by multiple loadings so as
to utilize the tractor power effectively with minimum
compaction effects. For this purpose, the finite element
method (FEM) was used to predict soil sinkage by multiple
loadings (ten loadings) of a rectangular plate and a
two-dimensional FEM program entitled PRESSINK was modified
and employed to perform required numerical calculations. The
agricultural soil was considered as an elastoplastic
material, and the Mohr-Coulomb elastoplastic material model
was adopted with the flow rule of associated plasticity.
Also, to deal with material non-linearity, incremental
method was adopted and to allow for the geometric
non-linearity, the total Lagrangian formulation was used.
The FEM analysis was finally verified through laboratory
test. Results of the laboratory test proved that the FEM is
a relatively accurate and powerful technique to predict soil
sinkage by multiple loadings. Results of the study also
indicated that the number of loadings noticeably affected
soil sinkage. Moreover, the first three loadings caused
critical soil sinkage and the amount of soil sinkage owing
to the first three loadings was about 91% and 82% of the
total soil sinkage based on the FEM analysis and laboratory
test results, respectively. |
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