ISSN 2375-1185
Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (3), pp. 265-271, May, 2015. © International Scholars Journals
Full Length Research Paper
A study on the determinant of chemical composition of the essential oils of Algerian citrus
Hussein S.A
University Hassiba Benbouali Chlef, Agronomy Institute, Hay Salem, 19 highway, 02000 Chlef, Algérie.
*Corresponding author. E-mail: [email protected]
Abstract
The aim of this study was to determine the chemical composition of the essential oils of Algerian citrus. They were extracted by hydrodistillation from the leaves of citrus species (orange, Bigaradier, mandarin and lemon), using gas chromatography/mass spectrometry (GC/MS). Their chemical composition and antifungal activity against four phytopathogenic fungi (Fusarium oxysporum f.sp., albedinis sp, Penicelium sp., Alternaria sp. and Fusarium sp.) were studied. The inhibiting minimal concentration (CMI) effect was also given for four oils. Ten compounds were recorded jointly among the 51 identified, of which limonene (7.18 to 36.10%), β-pinene (4.35 to 30.0%) and linalool (0.21 to 63.03%) represent the principal major compounds. These results indicate that essential oils can be employed as natural fungicides against phytopathogenic fungi.
Key words: GC/MS, essential oils , citrus, antifungal activity, phytopathogenic fungi.
Hussein S.A
Page: 265 - 271
https://doi.org/10.46882/AJA/1039Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (1), pp. 228-234, March, 2015. © International Scholars Journals
Full Length Research Paper
An assessment of wild Cicer species accessions for resistance to three pathotypes of Ascochyta rabiei (Pass.) Labr. in Algeria
Houari S.O, Bouteflika D.A and Lamamra A.A
Laboratory of Plant Protection, Department of Agronomy, University Abdelhamid Ibn Badis of Mostaganem, Mostaganem, Algeria.
*Corresponding author. E-mail: [email protected]
Abstract
Twenty-five (25) genotypes of five wild Cicer species (Cicer judaicum, Cicer bijugum, Cicer cuneatum, Cicer echinospermum and Cicer reticulatum) were screened for resistance to ascochyta blight disease caused by Ascochyta rabiei, by artificially inoculating the germplasm under glasshouse. Highly significant effect (P<0.01) was observed on their reaction to three pathotypes of A. rabiei (Mos02 ‘pathotype III: highly aggressive’, At02 ‘pathotype II: moderate aggressive’, and Sba02 ‘pathotype I: least aggressive’), there is a difference in genotypes reaction to A. rabiei isolates but very important resistance was observed (>50% of accessions collection). All five C. judaicum accessions are resistant to A. rabiei isolates, two resistant accessions in the wild species C. echinospermum (ILWC0 and ILWC246) and three accessions in C. reticulatum (ILWC81, ILWC104 and ILWC247), C. cuneatum (ILWC37, ILWC40 and ILWC232) and C. bijugum (ILWC195, ILWC285 and ILWC286).
Key words: Ascochyta rabiei, Cicer arietinum, Cicer sp., aggressiveness, resistance.
Houari S.O, Bouteflika D.A and Lamamra A.A
Page: 228 - 234
https://doi.org/10.46882/AJA/1040Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (3), pp. 244-256, May, 2015. © International Scholars Journals
Full Length Research Paper
A study on the pattern of land use/land cover change in the Lower Ogun River Basin between 1984 and 2012
Agbuna K.S, Adebayo S.M and Babatunji A.E
Department of Geography and Environmental Management, Niger Delta University, Wilberforce Island Bayelsa State, Bayelsa, Nigeria. E-mail: [email protected]
Accepted 23 January, 2015
Abstract
This study investigates the pattern of land use/land cover change in the Lower Ogun River Basin between 1984 and 2012. Two sets of topographical maps, a Landsat-5 TM image of 1984, Landsat-7 ETM+ of 2000 and a Google Earth image of 2012 were used for the study. The topographical maps and satellite images were digitally processed using ILWIS 3.2™ software and exported to ArcGIS 9.3™ for further processing and analysis. The processed images were subsequently classified using the maximum likelihood classification algorithm, resulting in the identification of seven land use classes. Furthermore, change detection analysis was carried out using Cross Module in ILWIS™. The result of the change detection analysis indicated that between 1984 and 2000, 80.08% of the land cover in the study area has been converted to other land uses while only 19.92% remained unchanged. Also, within the same period, light forests, non-forested wetlands and forested wetlands decreased at average annual rates of 8.26, 4.66 and 2.81%, respectively, while water bodies also decreased at an annual rate of 0.17%. On the other hand, farmland, shrubs and urban/built-up areas expanded at average annual rates of 7.23, 6.74 and 4.65%, respectively. The result further indicates that between 2000 and 2012, 49.86% of the land cover has been converted to other land uses, while 50.14% remained unchanged, and that farmlands, shrubs, urban/built-up areas and forested wetlands expanded at average annual rates of 6.01, 1.95, 0.89 and 0.17%, respectively, just as light forests, non-forested wetlands and water bodies decreased annually by 8.26, 2.70 and 1.40%, respectively. Five randomly collected soil samples were analyzed for their physicochemical properties. Findings show the growing impact of urban agriculture on wetland ecosystem within the study area, manifesting in soil degradation and biodiversity loss. The implication of these findings is that the area is susceptible to devastating flooding which can culminate in the loss of lives and properties. This study recommends the development of effective land management information system and policies that will ensure sustainable management of fragile ecosystem.
Key words: Change detection, river basin, urban agriculture, land use/land cover, wetlands.
Agbuna K.S, Adebayo S.M and Babatunji A.E
Page: 244 - 256
https://doi.org/10.46882/AJA/1038Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (3), pp. 257-258, May, 2015. © International Scholars Journals
Full Length Research Paper
Correlation and Heritability in Pearl Millet (Pennisetum glaucum (L) R. Br.
Yakubu Yahaya
Lake Chad Research Institute, P. M. B. 1293 Maiduguri, Nigeria. E-mail: [email protected]
Abstract
Ten genotypes of Pearl millet identified from the germplasm (Pennisetum glaucum (L) R. Br. were grown in a complete randomized block design with three replicates and the yield and four other yield contributing characters were studied. The coefficient of genotypic, phenotypic and environmental correlations and heritability in broad sense were worked out to determine the degree of association among the agronomic characters. A good amount of genetic variability for different characters were observed. Heritability of 1000-seed weight and grain yield was highest, whereas the number of productive tillers had low heritability. Grain yield was positive and significantly correlated with the number of productive tillers, panicle width, panicle length and 1000-seed weight. Significant negative correlation was observed between the number of productive tillers and panicle width. There was a positive association between the number of productive tillers, panicle length and 1000-seed weight and grain yield High significant association also existed between panicle width and panicle length.
Key word: Correlation, heritability, pearl millet, genetic advance.
Yakubu Yahaya
Page: 257 - 258
https://doi.org/10.46882/AJA/1043Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (2), pp. 235-243, April, 2015. © International Scholars Journals
Full Length Research Paper
An assessment of the effects of seed ageing, application of phytohormone and KNO3 on aged corn seeds
Bobak S.A, Parviz N.K and Ansari W.M
Department of Agronomy and Plant breeding, Dezful branch, Islamic Azad University Iran.
*Corresponding author. [email protected].
Abstract
Seed ageing is a main problem of seed storage. Unsuitable storage conditions with high moisture and temperature increases seed ageing. In fact, seed ageing results in the decrease of seed quality. Seed priming is known as a seed enhancement treatment which could improve seed germination and germination synchrony in many of crops. In this experiment we investigated effects of seed ageing, application of phytohormone and KNO3 on aged corn seeds. In order to improve germination characteristics in aged seeds phytohormone treatment using different gibberlline concentration (50, 100, 200, 400 and 800 ppm) and KNO3 (0.5, 1, 2.5 and 4%) were used. Results of study showed significant difference in aged seeds. It was also observed that with higher ageing duration, more germination characteristics decreased. Gibberlline at 400 ppm increased germination characteristics in aged seeds and had a positive effect on seed germination of aged corn seeds. KNO3 also had positive effects on seed germination of aged seed. This was higher in application of 0.5% KNO3 for 8 h and 2.5% for 24 h. Based on our results, it was suggested that seed ageing for higher duration could significantly decrease seed quality. Using seed enhancement treatments like seed priming or application of phytohormone could improve aged and non-aged seed performance especially for high aged seeds.
Key words: Seed, accelerated ageing, KNO3, gibberlline, seed priming, maize.
Bobak S.A, Parviz N.K and Ansari W.M
Page: 235 - 243
https://doi.org/10.46882/AJA/1042Research Article
African Journal of Agronomy ISSN: 2375-1185 Vol. 3 (3), pp. 259-264, May, 2015. © International Scholars Journals
Full Length Research Paper
Mitigating the adverse effects of chilling stress on rice seedling through application of spermidine as seed priming factor
Ferdowsi G.A
Department of Agronomy, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
*Corresponding author E-mail: ferdowsi. [email protected]
Abstract
Chilling stress is a major limiting factor for rice production in many parts of the world. The study was carried out in the Seed Research Laboratory of the Department of Crop Science, Ferdowsi University of Mashhad in summer 2011. Rice (cv. Khazar) seeds were soaked in 50, 150 and 300 mg L-1 spermidine aerated solutions for 48 h and then dried back to the original moisture content and were sown in three temperatures (28°C as normal, 12 and 8°C as chilling stress). Chilling stress (8°C) reduced the root (39%) and shoot (52%) growth in untreated seeds, while the reduction of 11% root growth and 20% shoot growth was observed when the seeds were primed with 300 mg L-1 spermidine solution. The electrolyte leakage (EL) of the seedling leaves significantly increased in low temperatures as it was 67% in 8°C in compared with normal condition. Chilling stress significantly increased superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in rice seedlings leaves though this increase was not significant for glutathione reductase (GR). Seed priming with spermidine had a positive effect on seedlings leaves antioxidant activity in every temperature conditions. As in 8°C, the sharp increase (73%) in SOD activity was occurred at 300 mg L-1 spermidine solution and it was 23 and 46% for CAT and APX, respectively. In general, seed priming with spermidine alleviated the chilling effect, probably as a result of activating antioxidants production processes and membrane stabilizing in cellular structures.
Key words: Antioxidant, chilling injury, polyamine, priming, seedlings.
Ferdowsi G.A
Page: 259 - 264
https://doi.org/10.46882/AJA/1041