African Journal of Agriculture

African Journal of Agriculture ISSN 2375-1134 Vol. 2 (3), pp. 081-084, March, 2015. © International Scholars Journals

Full Length Research Paper

Effects of Carboxin + Thiram doses on germination and vigor of three lots broccoli seeds, as well as on the incidence of fungi in treated seed

Montenegro Neymar Benicio

Faculdade de Ciências Agronômicas, Universidade Norte do Parana, Londrina, Brazil.

E-mail: [email protected]

Accepted 9 February, 2015

Abstract

The purpose of treating seeds chemically is to eradicate their pathogens and/or protect them against soil pathogens, mainly by germination time. However, there is little research on vegetables investigating the effect of this treatment on seed quality. Therefore, this study evaluates the effects of Carboxin + Thiram doses on germination and vigor of three lots of broccoli seeds, as well as on the incidence of fungi in treated seed. The 15 treatments were evaluated in a factorial system (3x5), with the first factor consisting of three lots of 'Avenger' broccoli seeds (lots 82744, 82745 and 82749), and the second factor consisting of five doses (0, 0.04, 0.06, 0.10 and 0.12% of a.i.) of Carboxin + Thiram fungicide (commercial name Vitavax-Thiran). The germination and seed vigor were evaluated, in addition to the presence of pathogens in seeds after treatment (blotter test). All lots showed high levels of germination and vigor. The lot 82749, however, showed higher value in plug test in substrate emergence (99%) than lot 82745 (95%). Regarding the treatment with Carboxin + Thiram, no changes in germination average (98%) and vigor were noticed (average for the first germination count, length, and dry weight of seedling, plug test at 10 days after sowing of 97%, 4.9 cm, 4.0 mg and 96%, respectively), showing that this fungicide, in the evaluated doses, does not affect the quality of broccoli seeds. As to seeds health, the pathogens Alternaria spp. and Fusarium spp. were detected, in addition to saprophytic species such as Penicillium, Aspergillus, Trichoderma, and Rhizopus. The higher incidence of Fusarium spp. was noticed in lot 82744, and the lowest in lot 82749. As to Penicillium spp., lot 82479 was the most contaminated. Regarding other fungi, the general incidence was very low and there was no difference between lots and doses used.

Key words: Brassica oleracea, seed treatment, fungicides.

African Journal of Agriculture ISSN 2375-1134 Vol. 2 (2), pp. 076-080, February, 2015. © International Scholars Journals

Full Length Research Paper

Use of the AMMI model to analyse cultivar-environment interaction in cotton under irrigation in South Africa

M. M. Pretorius^1*, J. Allemann² and M.F. Smith³

¹Agricultural Research Council – Institute for Industrial Crops, Private Bag X82075, Rustenburg, 0300

²Department of Soil, Crop and Climate Sciences, University of the Free State, Bloemfontein.  9301

³P. O Box 50505, Moreleta Village 0097, Pretoria, Gauteng Province, South Africa.

E-mail: [email protected]

Accepted 19 September, 2014.

Abstract 

Upland cotton (Gossypiumhirsutum L.) is considered to be the most important textile fiber crop in the world. Unpredictable weather patterns caused a need for the identification of stable genotypes that have specific adaptation to specific environments.  The objective of this study was to evaluate yield performance of different cotton cultivars under irrigation in South Africa by using the AMMI model.  Five genotypes were evaluated over three seasons (2003 to 2006) at six locations.  The additive main effects and multiplicative interaction (AMMI) statistical model was used to investigate the cultivar x environment interaction (GEI), yield stability and adaptation to environments.  AMMI analysis indicated that cotton yield showed highly significant differences (p<0.01) affected by Environments (E), genotypes (G) and genotype x environment interaction (GEI).  84.0 % of the total sum of squares was attributed to environmental fluctuations showing that the environments were diverse, with large differences among environmental means accounting for most of the variation in cotton yield.  Results showed that NuOPAL was the best performing cultivar in 15 out of 18 observations in fibre yields.

Key words:  AMMI model, cotton, cultivar x environment interaction.

African Journal of Agriculture ISSN 2375-1134 Vol. 2 (1), pp. 070-075, January, 2015. © International Scholars Journals

Full Length Research Paper

Proton consumption capacity, ash alkalinity and chemical characterization of travertine from different sources in Rwanda

Sirikare N.S.^1,3*, Naramabuye F.X.² Marwa E.¹ and Semu E ¹

¹ Sokoine University of Agriculture, Department of Soil Science, P. O. Box: 3008, Morogoro, Tanzania.

²University of Rwanda,Department of Soil Science and Environment, P.O. Box 117, Huye, Rwanda.

³Rwanda Agriculture Board, P.O.BOX 5016, Kigali, Rwanda.

E-mail:[email protected]

Accepted 06 August, 2014

Abstract

Soil acidification is among the major factors limiting the sustainability of agricultural production systems throughout the world and more specifically in Rwanda. Travertine samples collected from different deposits in Rwanda were examined for their chemical compositions. Calcium oxide (CaO) content, ash alkalinity and protons consumption capacity were determined as potential indicators to predict the efficiency of travertine. The results found revealed that the studied travertine deposits (Rwaza, Mashyuza, Gishyita and Mpenge) in Rwanda had 35 to 71.1 wt% CaO. Magnesium Oxide (MgO) ranged between 3.1 and 12.7 wt%. Travertine had micronutrients Cl, Zn, Cu, Mo and Co that can offset deficiency encountered in highly weathered Rwandan acidic soils. In addition, these travertine deposits had higher proton consumption capacity and ash alkalinity as compared to other liming materials. The study revealed positive linear correlations among all the investigated indicators, which could serve as a model for predicting proton consumption capacity and ash alkalinity of any liming material when its pH and CaO content are known. It was recommended that travertine from Rwanda could be used for soil acidity amelioration and a potential source of micronutrients for agricultural production. 

Key words: Rwanda, travertine, proton consumption capacity, ash alkalinity, chemical characterization, soil acidity.

African Journal of Agriculture Vol. 1 (3), pp. 030-034, September, 2013. © International Scholars Journals
 
Full Length Research Paper

Determining the tolerance level of Zea mays (maize) to a crude oil polluted agricultural soil

Josiah M. Ayotamuno* and Reginald B. Kogbara

Department of Agricultural and Environmental Engineering, Rivers State University of Science and Technology, P. M. B. 5080, Port Harcourt, Nigeria.

*Corresponding author. E-mail: [email protected]

Accepted 9 May, 2013

Abstract

This research sought to investigate the tolerance level of Zea mays (maize) on a crude oil contaminated soil using indices of plant performance such as plant height, leaf area and fresh cob yield. In the experiments described, conditions of a major spill were simulated by pouring different amounts of crude oil on experimental pots containing agricultural soil. Maize seeds were then grown amidst adequate fertilizer application and irrigation. The results of the study revealed that maize can survive soil contamination of about 21% (similar to 177 000 mg/kg) and still produce fresh cob yield of about 60% than on normal soil. There was a stimulated increase in fresh cob yield, than that obtained on normal soil at 12.5% soil contamination (similar to 112240 mg/kg). Hence, contaminant concentrations of 112 240 mg/kg and 177 000 mg/kg are identified as the ‘optimum yield limit’ and ‘lethal threshold’ respectively for maize growing on crude oil polluted soils. These results highlight the fact that, while concerted efforts should be made to remedy petroleum-contaminated agricultural soils, certain crops like maize can still produce beneficial yield in the presence of good soil management practices.

Key words: Contaminant concentrations, crude oil contamination, fresh cob yield, lethal threshold, optimum yield limit, plant height.

African Journal of Agriculture Vol. 1 (4), pp. 046-048, October, 2013. © International Scholars Journals
 
Full Length Research Paper

A simple and efficient procedure to enhance artemisinin content in Artemisia annua L. by seeding to salinity stress

Zhenghao Qian, Ke Gong, Ling Zhang, Jianbing Lv, Fuyuan Jing, Yueyue Wang, Shaobo Guan, Guofeng Wang and Kexuan Tang^*

School of Agriculture and Biology, School of Life Science and Technology, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, Shanghai Jiao Tong University, Shanghai 200030, China.

*Corresponding author. E-mail: [email protected] or [email protected]. Tel: 86-21-62932002. Fax: 86-21-62824073.

Accepted 4 May, 2013

Abstract

Artemisinin is an effective anti-malarial drug extracted from Artemisia annua L. Due to the low content of artemisinin in A. annua, great efforts have been devoted to improve artemisinin production. Here we report a simple and efficient procedure to enhance artemisinin content in A. annua by seeding to salinity stress. Our result shows that artemisinin content in the plant treated with 4 - 6 g/l NaCl could be significantly enhanced (up to 2 - 3% dry weight) compared to that in control plant (1% dry weight).

Key words: Artemisia annua L., artemisinin, NaCl, salinity stress.

African Journal of Agriculture Vol. 1 (4), pp. 035-045, October, 2013. © International Scholars Journals
 
Full Length Research Paper

Antibiotic resistance profiles and relatedness of enteric bacterial pathogens isolated from HIV/AIDS patients with and without diarrhoea and their household drinking water in rural communities in Limpopo Province South Africa

Obi C. L. ¹*, Ramalivhana J.², Momba M.N.B.⁵, Onabolu B.⁶, Igumbor J.O.³, Lukoto M. ³, Mulaudzi T.B.⁴, Bessong P.O.², Jansen van Rensburg E.L.⁶, Green E² and Ndou S²

¹College of Agriculture and Environmental Sciences, School of Agriculture and Life Sciences, University of South Africa,

Pretoria, South Africa.

²Department of Microbiogy, University of Venda, South Africa

³Department of Public Health University of Venda, South Africa

⁴Department of Statistics, University of Venda, South Africa.

⁵Department of Water Care, Tshwane University of Technology, Arcadia Campus, Pretoria.

⁶Department of Microbiology, University of Limpopo.

*Corresponding author. E -mail : [email protected], Tel : + 27 82 422 7580, Fax : + 27 12 352 4032

Accepted 8 August, 2013

Abstract

Antibiotic resistance profiles and the correlation of enteric bacterial pathogens from HIV positive indivi-duals with and without diarrhoea and their household drinking water were determined using the Kirby Bauer disk diffusion and polymerase chain reaction methods respectively. The sef gene of Salmonella enteritidis was amplified with the primer pair sefA-1 and sefA-2. The fliC gene of Salmonella typhimurium was amplified with the primer pair flicA- 1 and flicA -2. Heat-labile toxin ( LT ) primers (Lta and LTb) were used to amplify Escherichia coli isolates and VirA1 and VirA2 for the Vir A gene of Shigella dysenteriae. Results of antibiotic resistance profiles of enteric bacterial pathogens isolated from stool samples of HIV positive and negative individuals with and without diarrhea and their household drinking water showed very similar drug resistance patterns. Over 90% of all the organisms isolated from the various study cohorts showed resistance to penicillin, cloxacillin and amoxicillin. Conversely, almost all the organisms were sensitive to ciprofloxacin, gentamycin, meropenem and imipenem. About 50% of E. coli isolated from the various study cohorts showed multiple antibiotic resistance to penicillin, amoxicillin, ampicillin, erythromycin, tetracycline, doxycycline and cotri-moxazole ( P^R, A^R, AP^R, E^R, T^R, DXT^R, and TS^R ) whereas less than 10% resistance was consistently reported for ofloxacin, gentamycin, meropenem cefotaxime, cefuroxime and imipenem ( OFX^S, GM^S, MEM^S, CTX^S, CXM^S and IMI^S ). The majority of Salmonella and Shigella isolates from all the groups were sensitive to ciprofloxacin, gentamicin, amikacin, meropenem, imipenem, nalidixic acid, kanamycin, piperacillin-tazo bactam, cefuroxime, doxycyclin, cefepime and ceftazidime (CIP^S, GM^S, AK^S, MEM^S, IMI^S, NA^S, KN^S, DXT^S, CXM^S, CPM^S, CAZ^S and PTZ^S). For Campylobacter, over 30% of the isolates were resistant to erythromycin, ampicillin, tetracycline, cotrimoxazole and ceftazidime (E^R, AP^R TS^R and CAZ^R) whereas over 85% were susceptible to ciprofloxacin, ofloxacin, gentamycin, amikacin, mero-penem, and nalidixic acid (CIP^S, OFX^S, GM^S, AK^S, MEM^S and NA^S). In addition to penicillin, amoxicillin, ampicillin and erythromycin, Aeromonas and Plesiomonas spp were more resistant to chloramphenicol, but were susceptible to ciprofloxacin, gentamycin, amikacin, meropenem, imipenem and nalidixic acid (CIP^S, GM^S, AK^S, MEM^S, IMI^S and NAS). Polymerase Chain Reaction (PCR) experiments using targeted species genes of S. enteritidis, S. typhimurium, E. coli, Sh. dysenteriae showed that isolates from stool samples of HIV positive and HIV negative individuals with and without diarrhoea were also present in the household drinking water of the same study cohorts, suggesting that drinking water may have been the sources of the organisms in stool sample. Furthermore, by showing that the primers were able to amplify the genes in both clinical and environmental isolates, the link between the virulence of the pathogens was established.

Key words: Enteric, Bacteria, Pathogens, Antibiotics, HIV/AIDS, Household, Water, Diarrhoea.