Journal of Agricultural and Biological Science       ISSN 1990-6145
 
 
 

 
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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

 

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

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.

 
 
 
Full Text  

 
     

  

   

  

  

  

 

 

 

 

 

 

 

 

 

 

 

 

 

       arpnjournals.com                                                       Publishing Policy                                                  Review Process                                           Code of Ethics