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Journal of Agricultural and Biological Science
March 2009 | Vol. 4 No. 2 |
Title: |
Modeling of
soil total nitrogen based on soil organic carbon |
Author (s): |
Majid Rashidi
and Mohsen Seilsepour |
Abstract: |
There are
many cases in which it is desirable to determine empirical
relationships among some soil physical and chemical
properties. For instance, soil total nitrogen (TN) are often
determined using laborious and time consuming laboratory
tests, but it may be more suitable and economical to develop
a method which uses easily available soil properties. In
this study, a linear regression model for predicting soil TN
from soil organic carbon (OC) was suggested and soil TN was
estimated as a function of soil OC. The soil TN predicted
from the soil TN-OC model was compared to the soil TN
determined by laboratory test using the paired samples
t-test and the Bland-Altman approach. The soil TN predicted
by the soil TN-OC model was not significantly different from
the soil TN determined by laboratory test (P > 0.05). The
mean difference between the soil TN-OC model and laboratory
test was -0.002% (95% confidence interval: -0.008 and
0.004%; P = 0.510). The standard deviation of the soil TN
differences was 0.011%. The statistical results of the study
indicated that the soil TN-OC model provides an easy,
economic and brief methodology to estimate soil TN and in
order to predict soil TN based on soil OC the soil TN-OC
model TN = 0.026 + 0.067 OC with R2 = 0.83 can be
recommended. |
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Title: |
Standardization of storage conditions to prolong viability
of seeds of artocarpus heterophyllus lam- a tropical
fruit tree |
Author (s): |
Rekha R.
Warrier, B. Gurudev Singh, R. Anandalakshmi, V. Sivakumar,
S. Geetha, A. M. Kumar and Maheshwar T. Hegde |
Abstract: |
Recalcitrant seeds are desiccation and chilling sensitive
and are viable for a very short period. Seeds of
Artocarpus heterophyllus being recalcitrant in nature
pose storage problems. The present study was taken up to
identify methods to prolong seed viability of the species.
Seeds were stored at four different temperatures: Ambient
(25 ± 2˚C), 20˚C, 15˚C and 0 ± 2˚C and subjected to
germination tests at the end of 1, 2, 3, 4 and 5 weeks of
storage. Seeds stored at 20˚C retained viability for 5 weeks
with 41% germination. Experiments to store seeds with and
without bulb revealed that seeds should be extracted from
the bulb to ensure effective storage. The viability of seeds
can be prolonged to 32 weeks (with 48% germination) when
stored at 20˚C. |
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Title: |
Morphological
characterization of some wild and cultivated watermelon (citrullus
sp.) accessions in Kenya |
Author (s): |
Bernard M.
Gichimu, Barack O. Owuor, Gideon N. Mwai and Mathews M. Dida |
Abstract: |
Genetic
diversity and relatedness were assessed among three most
common commercial watermelon cultivars in Kenya; one newly
introduced commercial cultivar from the U.S., one Kenyan
landrace and one wild (Citrullus colocynthis)
accession. The six accessions were grown in the field for
two seasons under sub humid tropical conditions. Randomized
Complete Block Design (RCBD) with three replications was
used. Data was collected on morphological features of
watermelon which include vine, leaf, flower, fruit and seed
characteristics. A descriptor list with 21 morphological
(qualitative and quantitative) characters was adopted from
Diez et al., (2005) and Jarret and Griffin, (2007) and was
refined and used in characterization. The data was used to
calculate genetic similarity and to construct a dendrogram
using the unweighted pair-group method with arithmetic
average (UPGMA). Data on quantitative characters was
subjected to Analysis of Variance (ANOVA) using SAS
statistical package and effects declared significant at 5%
level. The procedure PRINCOMP was then used to perform a
principle component (PC) analysis using six quantitative
variables and accessions plotted on two dimensions using the
first two principle components (PC1 and PC2). The cluster
analysis results demonstrated high morphological diversity
(54-42%) between unimproved accessions (wild accession and
landrace) and commercial cultivars and low morphological
diversity (8-27%) among commercial cultivars. The ANOVA
conducted on quantitative characters of cultivated
accessions demonstrated highly significant variation between
accessions. Results of the principle component analyses for
the six quantitative traits indicated that the first two PCs
explained 68% and 29% (a total of 97%) of the total
variation. The low morphological diversity observed among
commercial cultivars emphasizes the need to expand the
genetic base of the cultivated watermelon in Kenya. |
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Title: |
Effects of
seed rate, row spacing and fertility levels on yield
attributes and yield of soybean under temperate conditions |
Author (s): |
Bilal Ahmad
Lone, Badrul Hasan, Amarjeet Singh, Haq S. A. and N. R. Sofi |
Abstract: |
A field
experiment was conducted at Shalimar Campus during Kharif
seasons of 2004 and 2005 on a silty clay loam soil, medium
in available N and K, low in available P to study the
production performance of soybean as influenced by seed
rate, row spacing and fertility levels under temperate
conditions. The experiment comprising 27 treatment
combinations viz., 3 levels each of seed rate (40, 60 and 80
kg ha-1), row spacing (30, 45 and 60 cm) and
fertility (40:60:40, 60:90:60 and 80:120:80 of N : P2O5
: K2O kg ha-1) was laid out in split
plot design replicated thrice. Lower seed rate i.e. 40 kg
ha-1 produced significantly higher number of
branches plant-1, test weight, number of pods
plant-1 and seeds pod-1. Contrary to this, seed
and straw yield were found significantly superior under seed
rate of 80 kg ha-1 over 40 kg ha-1.
The extent of increase was 21.75% for grain yield and 20.68%
for straw yield. Whereas row spacing of 45 cm proved
significantly superior over 30 cm and remained at par with
60 cm for grain and straw yield. The extent of increase in
grain yield at 45 cm row to row spacing was 13.14% when
compared to 30 cm row to row spacing. Application of N80
P120 K80 kg ha-1
significantly improved the growth parameters viz., number of
pods plant-1, grain and straw yield over N40
P60 K40 kg ha-1. The
extents of increase were 12.5% for grain yield and 7.36% for
straw yield. |
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Title: |
Interactive
effects of relative humidity, coating method and storage
period on quality of carrot (cv. nantes) during cold storage |
Author (s): |
Majid Rashidi
and Mahdi Hosseini Bahri |
Abstract: |
This study
was conducted on the interactive effects of Relative
Humidity (RH), Coating Method (CM) and Storage Period (SP)
on Nantes carrot during cold storage at temperature of
0.5°C. Two RH (85% and 90%), four CM [Carboxy Methyl
Cellulose + Cellophane Film (CMC + CF), Carboxy Methyl
Cellulose (CMC), Cellophane Film (CF) and No-Coating (NC)]
and nine SP (0, 30, 45, 60, 75, 90, 100, 110 and 120-days)
were investigated for some qualitative characteristics
including water content, total soluble solids (TSS),
reducing sugar and firmness. A factorial experiment design
was laid out in completely randomized design with 3
replications for each one of factors and Duncan’s multiple
range tests were performed to compare the means of different
treatments. The statistical results of the study indicated
that RH, CM and SP significantly (P ≤ 0.01) affected all
traits. Interactions of RH × SP, CM × SP for all traits, and
RH × CM for water content and TSS were also significant. The
statistical results of the study also indicated that at 90%
RH, carrots were firmer, and had higher water content and
reducing sugar than 85% RH. Moreover, CMC + CF for water
content and reducing sugar, and CF for firmness were the
best CM. In addition, water content, reducing sugar and
firmness decreased by increasing the SP, whereas TSS
increased by an increase in SP. |
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Title: |
Calculation of
energy requirement and energy efficiency for production of
major agricultural crops |
Author (s): |
Ahmad Gholami
and Saeed Sharafi |
Abstract: |
This study
was carried out to determine the energy use in the Iran
agricultural sector for the period of 1980-2005 to evaluate
the impact of energy input to produce output. The inputs in
the calculation of energy use include human labor,
machinery, electricity, fertilizers, seeds and output energy
included 16 agricultural crops yield. Energy values were
calculated by multiplying the amounts of inputs and outputs
by their energy equivalents with the use of related
conversion factors. The energy efficiency is determined by
dividing the output value by the input value. The results
indicated that the total energy input increased from 55.64
×109 MJ/ha in 1980 to 150.71×109 MJ/ha
in the year 2005. Similarly, total output energy rose from
325.56×109 to 535.15×109 MJ/ha in the
same period. It was found that energy efficiency was
declined from 5.85% in 1980 to 3.55% in 2005, which
indicates that the energy input increased faster than energy
output. It also indicates that the use of inputs in Iran
agricultural production was not accompanied by the same
results in the final product. This can lead to problems
associated with these inputs, such as global warming,
nutrient loading and pesticide pollution. Therefore, there
is a need to choose a new policy to force producers to
undertake energy efficient practices to establish
sustainable production systems. |
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Title: |
Induced
mutagenesis for seed quality traits in Ethiopian mustard (brassica
carinata a. braun) |
Author (s): |
F. A. Sheikh,
B. Lone, S. Najeeb, Asif B. Shikari, G. A. Parray, A. G.
Rather, R. R. and R. S. Khudwani |
Abstract: |
Present
study was undertaken to broaden the genetic base in
Brassica carinata cv. PC 5 for seed quality traits
through induced mutagenesis. Mutagenesis with 0.5 per cent
ethyl methane sulphonate followed by selfing in M1
and screening for fatty acid composition through half seed
method in M2 and M3 generations led to
the identification of stable M4 progenies having
desirable fatty acid profile. One of the progeny EMS 9-56
appeared especially promising as it had about 24 percent
erucic acid, 30 per cent oleic acid, and 40 percent oil
content as against corresponding values of 46 percent, 11
percent and 34.2 percent in base variety, PC 5. Increase in
oil content to 40.6 per cent was a significant achievement
of the study as B. carinata germplasm lacks
variability for this important trait. |
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Title: |
Effects of
variety, crop arrangement and period of weed interference on
the performance of maize grown in mixture in northern guinea
savannah of Nigeria |
Author (s): |
Shinggu C.P,
Dadari S.A, Shebayan J.A.Y., D.I. Adekpe and D.B. Ishaya |
Abstract: |
Field
trials on the effects of variety, crop arrangement and
period of weed interference on the performance of maize
grown in mixture were conducted at the Institute for
Agricultural Research farm, Samaru (11011 N; 07038’ E and
686m above sea level) in the Northern Guinea Savanna
ecological Zone of Nigeria during the wet season of 2000 and
2001. Extra early maize TZEE-W was used as test crop, two
cowpea varieties (Kanannado and Sampea 7): two crop
arrangements (alternate row and alternate stand
arrangements) and ten periods of weed interference (weed
free till 3, 6, 9, 12 weeks after sowing (WAS) and harvest
and a corresponding set that were kept initially weed
infested till 3,6,9,12 WAS and harvest. Two treatments were
left weed free or weed infested throughout the crop life
cycle. The treatments were evaluated in a split-plot design
with varieties and crop arrangements allotted to main plot
and period of weed interference to sub-plot. Varieties,
crops arrangement and period of weed interference had
significant effect on weed growth and yield parameters of
maize. Maize grown in mixture with Kanannado gave lower weed
dry matter (WDM), higher crop vigour score (CVS), higher
grain yield and 100-grain weight. Maize in alternate row
arrangement performs better than maize in alternate stand
arrangement. Keeping the crop weed free till 6 WAS and
beyond gave better crop performance. |
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Title: |
Phosphatase
and urease instability caused by pesticides present in soil
improved by grounded rice straw |
Author (s): |
M. Rahmansyah,
S. Antonius and N. Sulistinah |
Abstract: |
Phosphatase
and urease were involved to the mineralization of phosphorus
and nitrogen compound in soil. In this observation, these
enzymes examined through 12 weeks incubation of the soil
containing pesticide and compared to free pesticide one. The
treatment executed in greenhouse for incubation. Phosphatase
had been lower activity compared to urease of all action.
These activities fluctuated in the beginning and decline to
12 weeks incubation. Phosphatase and urease increased in 2
weeks incubation, 2.45 and 49.25 unit/g soils respectively.
Urease was more responsive to soil containing pesticide
evaluated to phosphatase activity. Carbon dioxide release as
caused of soil microbial respiration most advantageous at 4
weeks incubation in soil free (B soil; 2.96 mg/g/hour) and
long-lasting healing with pesticide (A soil;2.55mg/g/hour),
compared to the soil containing fresh pesticides which was
peaked later at 6 week incubation (1.82 mg/g/hour). Organic
substance (grounded rice straw) amended into soil was
strongly to implicate respiration rate, phosphatase, and
urease activities concerning to soil containing pesticide.
The result should make representative work in effort to
evaluate phosphatase and urease related to mineralization
process within and without pesticide degradation in soil, as
well as caused by rice straw organic compound augmentation
to the soil containing pesticide. |
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Title: |
Modeling of
soil total nitrogen based on soil available phosphorous |
Author (s): |
Majid Rashidi
and Mohsen Seilsepour |
Abstract: |
A well
established regression model is a useful tool in development
of prediction method of some soil physical or chemical
properties, and can be used to investigate and analyze the
soil. In this study, a linear regression model for
predicting soil total nitrogen (TN) from soil available
phosphorous (AP) was suggested and soil TN was estimated as
a function of soil AP. The soil TN predicted from the soil
TN-AP model was compared to the soil TN determined by
laboratory test using the paired samples t-test and the
Bland-Altman approach. The soil TN predicted by the soil
TN-AP model was not significantly different from the soil TN
determined by laboratory test (P > 0.05). The mean
difference between the soil TN-AP model and laboratory test
was -0.0007% (95% confidence interval: -0.0104 and 0.0090; P
= 0.885). The standard deviation of the soil TN differences
was 0.0175%. The statistical results of the study indicated
that the soil TN-AP model provides an easy, economic and
brief methodology to estimate soil TN and in order to
predict soil TN based on soil AP the soil TN-AP model TN =
0.052 + 0.003 AP with R2 = 0.70 can be
recommended. |
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Title: |
Simulation of
maize crop under irrigated and rainfed conditions with
CROPWAT model |
Author (s): |
Muhammad
Nazeer |
Abstract: |
CROPWAT is
an irrigation management and planning model simulating the
complex relationships of on-farm parameters the climate,
crop and soil. The CROPWAT facilitate the estimate of the
crop evapotranspiration, irrigation schedule and
agricultural water requirements with different cropping
patterns for irrigation planning. The field experimental
data of maize crop from the Mardan district of NWFP,
Pakistan were collected and analyzed, then input the results
to the CROPWAT irrigation management model that was
developed by the Food Agricultural Organization (FAO). The
aim of this paper is to study CROPWAT simulation under
irrigated and rainfed conditions for maize crop, in order to
provide information necessary in taking decisions on
irrigation management. The model, that calculates
Evapotranspiration and crop water requirements, allows the
development of recommendations for improved irrigation
practices, the planning of irrigation schedules under
varying water supply conditions and yields reduction under
various conditions. For the purpose of this paper, the model
was run for the specific weather conditions of the year
2006, at two demonstration plots located in Mardan district
of NWFP, Pakistan. Simulation results analysis suggests that
areas, where the maize water requirements exceeds the water
supply, by application of adequate irrigation scheduling the
yield losses can be significantly reduced. |
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Title: |
Structure and
TIV potential of plant diversity under leucaena
canopy with reference to herbal-medicinal economy in semi
arid zone |
Author (s): |
Poonam
Mehrotra, Preeti Dwivedi, Azad S. Yadav and Geeta Kharkwal |
Abstract: |
The study
work was carried out in Leucaena plantation sites
located in and around Jhansi. Three sites of Leucaena
plantation were selected i.e. Leucaena plantation at
seasonal standing water (SSW site), Leucaena
plantation (LP site) at forest site, and Leucaena
plantation along the perennial water stream (PWS site). The
study showed that density of Leucaena was maximum at
PWS site and minimum at PS site. The density, canopy cover,
sapling density, seedling density of Leucaena tree
was highest at PWS site as compared to other sites. Number
of plant species, families and genus were highest at SSW
site. SSW site showed highest economic importance for
medicine as compared to food, fodder, fiber and oil yielding
species. Total important value (TIV) with reference to
medicinal properties was also highest at SSW site as
compared to other sites. Few plant species contained resin,
fatty oil, riboflavin, saponins, tannis etc. The main
indications for medicinal plants use were against common
cough/cold, fever, skin diseases, inflammation, eye problem,
chronic diseases and digestion problem in general and as
tranquilizers. The present analysis projects that majority
of herb species were medicinally important and a high number
of medicinal plants owing broad-spectrum medicinal value for
the major human population of the semi arid region. The
present study revealed that Leucaena developed and
harbours the herb diversity at less moisture content site. |
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