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Search Results: 1 - 10 of 462071 matches for " A. Kalonji-Mbuyi "
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Epidemiology of the Groundnut (Arachis hypogaea L.) Leaf Spot Disease: Genetic Analysis and Developmental Cycles  [PDF]
L. Tshilenge-Lukanda, K. K. C. Nkongolo, A. Kalonji-Mbuyi, R. V. Kizungu
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.35070
Abstract: Groundnut leaf spot is one of the important factors limiting groundnut productivity in Africa particularly in the Democratic Republic of Congo (DR Congo). Early and late leaf spot disease of groundnut caused by Cercospora arachidicola Hori and Cercosporidium personatum (Berk & Curt.) Deighton, respectively, can cause considerable yield losses without fungicide management. The main objectives of this research were to analyze plant and disease developmental cycles. Significant differences were observed among the groundnut varieties evaluated for resistance to the leaf spot disease. The results show that plant development cycle can be divided into three developmental stages. A first stage characterized by a low production of leaves, a second stage with a significant leaf development and finally a third stage with a reduction of leaves. Interestingly, the leaf spot disease cycle was also divided in three stages. The disease stage characterized by the highest level of symptom expression was not associated with the plant phase with the highest emerged leaves. Disease symptoms reached the highest pick only after the phase of intense leaf development. The molecular analysis revealed that all the groundnut varieties analyzed were genetically closely related even though they showed different reactions to the leaf spot disease.
Effect of Gamma Irradiation on Morpho-Agronomic Characteristics of Groundnut (Arachis hypogaea L.)  [PDF]
L. Tshilenge-Lukanda, A. Kalonji-Mbuyi, K. K. C. Nkongolo, R. V. Kizungu
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.411271
Abstract:

Induced mutation in plant improvement has been used in several crops to generate new sources of genetic variations. A study was conducted to determine the effect of different doses of gamma irradiation on different morpho-agronomic characteristics. Agronomic traits that were analyzed included: grain yield, number of pods/plant, number of seeds/plant and weight of 100 seeds and numbers of days to 50% flowering. Morphometric characterisation of the descriptive data included plant height, stem diameter, number of leaves/plant, leaflet length, leaflet width and number of ramification/ plant. Groundnut seeds were treated with various doses of gamma rays (100, 200, 400 and 600 Gy). Among the various dose treatments, gamma rays treatment at 100 Gy resulted in a higher increase of grain yield and other morpho-agronomic parameters especially for the JL24 variety. In fact the gamma irradiation at 100 Gy increased significantly grain yield by 14% for JL24, and 4 % for JL12. The number of pods per plant was increased by 2% for JL12 and 37% for JL24. For the number of seeds per plant, there was a significant increase of 8% for JL12, and 62% for JL24 at 100 Gy. A similar trend was observed for the JL24 at 200 Gy dose. Higher doses of gamma rays (400 and 600 Gy) reduced significantly plant growth and grain yield. The usefulness of the mutants identified in a groundnut breeding program is discussed.

Characterization of Congolese Strains of Xanthomonas axonopodis pv. manihotis Associated with Cassava Bacterial Blight  [PDF]
G. Mamba-Mbayi, P. Tshilenge-Djim, K. K. Nkongolo, A. Kalonji-Mbuyi
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.59132
Abstract:

Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis has been reported in several African countries since 1970. Knowledge of the virulence and diversity of Xanthomonas axonopodis pv. manihotis strains is important for an integrated control of CBB. The main objective of the present study was to characterize strains of Xanthomonas axonopodis collected from various regions in the DR-Congo. There was variability among strains for shape (form), contour (margin) and elevation. Bacterial cell size for the strains analyzed varied from 24.1 μm × 11.3 μm to 11.4 μm × 4.2 μm. All the Xanthomonas axonopodis pv. manihotis

Effect of Gamma Irradiation on Morpho-Agronomic Characteristics of Soybeans (Glycine max L.)  [PDF]
Justin Mudibu, Kabwe K. C. Nkongolo, Adrien Kalonji-Mbuyi, Roger V. Kizungu
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.33039
Abstract: Mutation breeding in crop plants is an effective approach in improvement of crop having narrow genetic base such as soybean. The main objective of the present study is to determine the effect of different doses of gamma irradiation on different morpho-agronomic characteristics. Agronomic traits that were analyzed included; grain yield, number of pods/plant, number of seeds/plant and weight of 100 seeds and numbers of days to 50% flowering. Morphometric characterization of the descriptive data included plant height, stem diameter, number of leaves/plant, leaflet length, leaflet width, number of ramifications/plant, and pod length and width at 3 lodge stage. The results of the present study revealed that the two gamma irradiation doses used (0.2 kGy and 0.4 kGy) decreased significantly most of agronomic and morphological traits evaluated in M1 populations. Different effects of 0.2 kGy and 0.4 kGy irradiation were observed in M2 populations with significant increase of grain yields and yield components in all the three soybean varieties. In general, a significant decrease or no changes of morphological traits were observed for the two irradiation doses in M2 populations. The levels of changes varied among varieties. Potential high yielding mutants were identified in progenies of irradiated seeds.
Incidence, Severity and Gravity of Cassava Mosaic Disease in Savannah Agro-Ecological Region of DR-Congo: Analysis of Agro-Environmental Factors  [PDF]
Marcel Muengula-Manyi, Kabwe K. Nkongolo, Claude Bragard, Patrick Tshilenge-Djim, Stephan Winter, Adrien Kalonji-Mbuyi
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.34061
Abstract: African Cassava mosaic disease (ACMD) is the most severe and widespread disease caused by viruses limiting production of the crop in sub-Saharan Africa. The objective of the present study was to evaluate CMD incidence, severity, and gravity under different agro-environmental conditions. A total of 222 fields were surveyed in 23 different locations. All the farmers grow only local cassava varieties without applications of fertilizers. Overall, mean CMD incidences for all sites surveyed were 58.2% and 51.7%, in 2009 and 2010, respectively. Disease severity ranged from 2.4 to 3.1 on a scale of 1 to 5. Mean disease gravity varied from 29.7% to 62%, in 2010, and 2009, respectively. Detailed analysis of agronomic and environmental revealed no significant association between cassava stand locations, age, land topography and the development of CMD. Likewise intercropping practices and field topping did not affect the development of CMD in all the fields surveyed. There were significant differences in the number of white flies (Bemisia tabaci) per plant in 2009 and 2010, but no significant correlations between the number of B. tabaci per plant and CMD incidence, severity, and gravity was found. In most fields, CMD appears to originate mostly from unhealthy cassava cuttings used for planting.
Assessing Reactions of Genetically Improved and Local Cassava Varieties to Cassava Mosaic Disease (CMD) Infection in a Savannah Region of the DR-Congo  [PDF]
Marcel Muengula-Manyi, Lyna Mukwa, Kabwe K. Nkongolo, Patrick Tshilenge-Djim, Stephan Winter, Claude Bragard, Adrien Kalonji-Mbuyi
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.44101
Abstract:

The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varieties were planted using randomized complete block design with three replications. The rate of cuttings sprouted varied significantly from variety to variety and from location to location. Local varieties were severely infected than improved varieties throughout the trial period. In general, the level of CMD incidence for genetically improved varieties was below 15% while it reached 100% for the local cassava varieties six months after planting (MAP). This trend was also observed for the CMD severity and gravity. The mean scores for CMD severity were 2 and 3.6 for genetically improved and local varieties, respectively at 6 MAP. CMD gravity for improved varieties was below 21% for genetically improved varieties and exceeded 85% for local varieties at the end of trials. Area Under the Severity index Progress Curve (AUSiPC) and Area Under Disease Progress Curve (AUDPC) estimates confirmed that improved varieties were moderately infested comparatively to local varieties. Molecular analysis is being conducted to determine the genetic variability and complexity of the cassava mosaic virus strains involved.

Study of the Master-Slave replication in a distributed database
Kalonji Kalala Hercule,Mbuyi Mukendi Eugene,Boale Bomolo Paulin,Lilongo Bokaletumba Joel
International Journal of Computer Science Issues , 2011,
Abstract: In a distributed database, data replication can be used to increase reliability, and availability of data. Updating a copy should be passed automatically to all its replicas. Generally, an update of data by the peer who has a new version involves not spread to those replicating this data. No form of consistency between replicas is guaranteed. In this paper we propose the study "Replication Master-Slave", which is a way of replicating data used in a distributed database. We will do a brief overview on some principles of distributed databases. Then we will present the different types of replication, the value of using this mode of replication Master exclave. Then we will end up a banking application based on the replication Master-Slave on the Oracle 10g platform.
Using CSS XML Files in Representing Biological Data-Case of Congolese Metazoa
Kalonji Kalala Hercule,Mbuyi Mukendi Eugene,Mulopo Tona David,Malekani M Jean
International Journal of Computer Science Issues , 2011,
Abstract: The present study is dealing with creating an xml file which will include all information on metazoans. Then, a file written in CSS (Cascading Style Sheets) will be created to allow the display of the XML (eXtensible Markup Language) file in a web browser. That technique will be able to permit an accurate and rapid search on information on metazoans. This will permit metazoan data to be integrated easily in interoperable applications on the Internet. This paper will allow biologists to be able to accommodate all the wildlife in a web application. We have represented Metazoans in a graph. And we used that graph to create our XML file.
Occurrence and Distribution of Banana bunchy top virus Related Agro-Ecosystem in South Western, Democratic Republic of Congo  [PDF]
Lyna Fama Tongo Mukwa, M. Muengula, I. Zinga, A. Kalonji, M. L. Iskra-Caruana, C. Bragard
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.55079
Abstract:

Banana bunchy top virus (BBTV) is one of the most severe and widespread virus limiting production and distribution of planting material of banana (Musa spp.) crops in the world. In Democratic Republic of Congo (DRC), these crops play a major role in daily life of almost 70% of citizen. Many factors influence banana production negatively such as Banana bunchy top disease. Epidemiological survey was conducted in experimental stations and farmers’ fields for two consecutive seasons covering 72 sites in five provinces of south western of RDC. The objective of this study was to evaluate the presence and distribution of the Banana bunchy top virus in five provinces of South Western of DRC, with emphasis on the agro-ecological factors. A total of 174 Musa spp. leaves samples were collected and analyzed by PCR. The results revealed the presence of BBTV in all provinces investigated. The frequency of BBTV was 6.3% in Bandundu, 12.1% in Kasa?Oriental, 17.8% Bas Congo, 1.1% in Katanga and 7.5% Kinshasa Urban and Peri-urban. Results also revealed that BBTV occurred in experimental station and farmers’ fields, both having all cooking and dessert bananas. The high prevalence of BBTV seemed to be linked to multiple introductions of planting materials in the Bas Congo province during 1990 and 2002. However, the province of Katanga had not experienced the introduction of planting material. This factor would explain the lowest prevalence of Banana bunchy top virus in this province. The results indicated that there was a real need to facilitate access to genetically improved and healthy certified planting material in these provinces.

Genetic variation in Coffea canephora L. (Var. Robusta) accessions from the founder gene pool evaluated with ISSR and RAPD
P Tshilenge, KK Nkongolo, M Mehes, A Kalonji
African Journal of Biotechnology , 2009,
Abstract: Discovered in Congo in 1898, Coffea canefora var. robusta accounts for 25 to 40% of the coffee grown in the world. Most genetic diversity of robusta coffee accessions conserved in ex situ collections has been estimated from morphological characteristics. There are limited studies on genetic variability and diversity in C. robusta. Inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) markers were used to assess the level of genetic variability among robusta coffee accessions from the founder gene pool in the Democratic Republic of Congo (DRC). The present study clearly established the high variability in the Congolese genepool. RAPD primers detected a higher level of polymorphic loci (95%) than ISSR markers (52%). Each accession could be genotyped using RAPD markers and both markers were efficient in revealing the genetic variability. Jaccard’s similarity coefficients generated to determine the genetic distances among accessions, revealed that most of the accessions were genetically distant from each other. The accessions tested represent useful genetic materials for breeding for resistance to tracheomycose and other traits in DRC.
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