Tusiime Geoffrey - Academia.edu (original) (raw)

Papers by Tusiime Geoffrey

Research Square (Research Square), Jun 6, 2022

Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa.... more Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa. To increase the production, substantial upgrading must be accomplished by enlarging the genetic potential of new cultivars that relays on the parents' genetic diversity. We aimed to assess the genetic diversity and the population structure of soybean accessions, therefore, evaluate soybean value in terms of use for breeding purposes. To accomplish this, a set of 282 soybean accessions were genotyped using the Diversity Array Technology Sequencing with a high throughput of the Single-nucleotide polymorphisms (SNPs). A total of 6,935 high-quality SNPs were identi ed across the whole soybean genome. The mean value of genetic diversity, major alleles frequency, minor alleles frequency, expected heterozygosity, and the polymorphism information content was respectively estimated at 0.35, 0.77, 0.22, 0.33, and 0.29. The analysis of molecular variance reveals that the variance among the populations is lower than the variance within the populations. The soybean accessions could be classi ed into two groups based on the model-based population structure and the principal coordinate analysis or into three groups based on the discriminant analysis of the principal component and the Neighbor-joining tree. The information provided in this study will be helpful for breeders.

Research Square (Research Square), Aug 1, 2022

Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa.... more Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa. To increase the production, substantial upgrading must be accomplished by enlarging the genetic potential of new cultivars that relays on the parents' genetic diversity. We aimed to assess the genetic diversity and the population structure of soybean accessions, therefore, evaluate soybean value in terms of use for breeding purposes. To accomplish this, a set of 282 soybean accessions were genotyped using the Diversity Array Technology Sequencing with a high throughput of the Single-nucleotide polymorphisms (SNPs). A total of 6,935 high-quality SNPs were identified across the whole soybean genome. The mean value of genetic diversity, major alleles frequency, minor alleles frequency, expected heterozygosity, and the polymorphism information content was respectively estimated at 0.35, 0.77, 0.22, 0.33, and 0.29. The analysis of molecular variance reveals that the variance among the populations is lower than the variance within the populations. The soybean accessions could be classified into two groups based on the model-based population structure and the principal coordinate analysis or into three groups based on the discriminant analysis of the principal component and the Neighbor-joining tree. The information provided in this study will be helpful for breeders.

International Journal of Environment, Agriculture and Biotechnology, 2018

Sorghum is the third most important staple cereal crop in Uganda after maize and millet. Downy mi... more Sorghum is the third most important staple cereal crop in Uganda after maize and millet. Downy mildew disease is one of the most devastating fungal diseases which limits the production and productivity of the crop. The disease is caused by an obligate fungus, Peronosclerospora sorghi (Weston & Uppal) with varying symptoms. Information on the genetic diversity and population structure of P.sorghi in sorghum is imperative for the screening and selection for resistant genotypes and further monitoring possible mutant(s) of the pathogen. Isolates of P. sorghi infecting sorghum are difficult to discriminate when morphological descriptors are used. The use of molecular markers is efficient, and reliably precised for characterizing P. sorghi isolates. This study was undertaken to assess the level of genetic diversity and population structure that exist in P. sorghi isolates in Uganda. A total of 195 P. sorghi isolates, sampled from 13 different geographic populations from 10 different regio...

African Journal of Biotechnology, 2009

The Random Amplification of Polymorphic DNA (RAPD) analysis was used to detect the genetic divers... more The Random Amplification of Polymorphic DNA (RAPD) analysis was used to detect the genetic diversity among Ugandan isolates of Xanthomonas campestris pv. musacearum (Xcm), the causal agent of banana Xanthomonas wilt (BXW) disease. Seven random primers were used because of their ability to amplify reproducible and reliable fingerprints generated between 6 - 12 amplicons each from the Xcm isolates obtained from central core of pseudostems, peduncles, fruit peelings, sap, nectar, insects’ bodies and bacterial oozes. Regardless of the source and geographical origin, similar fingerprints were generated from the tested isolates. Using a similarity coefficient of 58%, the unweighted pair group method with arithmetic averaging (UPGMA) analysis did not reveal any significant differences in clustering, with exception of a single isolate that had unique fingerprints. Prior to the genetic analysis, all the isolates compared showed no significant difference (P = 0.92) with regard to incubation p...

Journal of Plant breeding and Crop Science, 2017

Fusarium related root rots have been associated with reduced cowpea productivity in Uganda. Sourc... more Fusarium related root rots have been associated with reduced cowpea productivity in Uganda. Sources of genetic resistance to Fusarium redolens which was found to be the most virulent have been identified but the mode of inheritance of the genes conferring the resistance is unknown. This study aims to investigate how the genes for resistance to F. redolens are inherited in cowpea. Four F. redolens root rot resistant cowpea genotypes were crossed with four intermediately resistant and 2 susceptible cowpea genotypes using North Carolina mating design II. The F1 and the parents were evaluated and data were collected on resistance to seed rot, leaf chlorophyll amount, produced lateral roots, response to plant mortality and root rot severity. Results revealed that additive gene effects were significant for all evaluated traits and non-additive genetic effects were significant in resistance to seed rot and chlorophyll amount. General combining ability (GCA) effects showed that the Asontem ...

In 2014, researchers in Uganda spotted signs typical bacterial leaf streak disease (Xanthomonas o... more In 2014, researchers in Uganda spotted signs typical bacterial leaf streak disease (Xanthomonas oryzae pv. oryzicola) in rice fields in Eastern Uganda. The disease was later confirmed to be bacterial leaf streak. In order to effectively plan for measures to manage this potentially devastating disease, it was imperative to score rice germplasm in Uganda for reaction to Xoc. Eighty four genotypes from the National Rice Improvement program were evaluated for their reaction to BLS using two Xoc isolates collected from Namulonge and Iganga. These were inoculated by the infiltration method using a needless syringe 30 days after planting. Data were collected on the streak length induced by BLS on the leaves 15 days after inoculation. The mean streak length per genotype was interpreted as; Resistant (R), 030mm. Genotypes showed signficant variability (P Xoc isolates reacted signficantly differently (P=0.011) on the rice genotypes. For the Iganga isolate, 6 genotypes were resistant while 17 ...

International Journal of Environment, Agriculture and Biotechnology

African Journal of Agricultural Research

Many landraces and improved cultivars of sorghum (Sorghum bicolor) grown in Uganda have late matu... more Many landraces and improved cultivars of sorghum (Sorghum bicolor) grown in Uganda have late maturity and are susceptible to several biotic and abiotic stresses. Introgression of the rhizomatous trait from perennial sorghum (Sorghum halepense) could improve stress tolerance. However, phenotypic characterization of exotic perennial sorghum germplasm under Ugandan environmental conditions is essential to select desirable genotypes. Rhizome-forming capacity of 192 S. bicolor × S. halepense backcross tetraploid families developed in a temperate North American environment was evaluated at two locations in Uganda over two consecutive growing seasons. Numbers of rhizomes and emerging shoots as well as mean distances from shoot to crown were evaluated. Forty-seven percent of families were moderately to strongly rhizomatous in the first season of growth and this value rose to 91% in the second season. Developing perennial grain sorghum for East Africa will require hybridization between exotic perennial and locally adapted germplasm. Screening for emerging rhizome-derived shoots in early generations is simple, rapid, and effective; however, more detailed selection based on both aboveground and belowground rhizome traits is recommended for later generations. Researchers and farmers should work together to find suitable ways in which perennial sorghum might fit into new types of crop and livestock systems.

International Journal of Advanced Research

Sorghum (Sorghum bicolor) ranks as the third most important staple cereal food crop in Uganda aft... more Sorghum (Sorghum bicolor) ranks as the third most important staple cereal food crop in Uganda after maize and millet. The crop is hampered by several biotic stresses of which Sorghum Downy Mildew disease is one of the most devastating diseases. The disease is caused by a soil-borne fungus Peronosclerospora sorghi but it is also airborne through conidia. Incidence and severity of downy mildew were conducted between March-June, 2016 and September-December 2016 growing seasons in 13 sorghum-growing districts across ten agroecological zones. Data collected were subjected to analyses of variance, correlation and linear regression. Significant (P < 0.001) differences were recorded for disease incidence and severity across the different agro-ecologies. The mean downy mildew disease incidence varied significantly (P< 0.001) from 49.4 % for Pader to 78.9 % for Namutumba. Disease severity varied significantly (P <0.001) from 2.3 for Pader to 3.5 for Pallisa. Chi-square test for independent association between cropping season and downy mildew disease incidence showed a high significant test statistic values (χ2 = 140.89, d.f = 3, and P < 0.001). A significant (P<0.001) positive correlation was observed between disease incidence and severity (r = 0.498) while a significant negative correlation was observed between disease incidence and rainfall (r =-0.675) due largely to temperature and relative humidity. Multiple linear regression analysis revealed that temperature, relative humidity, rainfall and altitude explained 49 % of the total variation associated to disease incidence. Variations in the incidence and severity of downy mildew disease prompt the need to screen for resistant/tolerant sorghum varieties.

International Journal of Phytopathology

Pineapple (Ananas comosus L. Merr) is an economic horticultural crop in Uganda. However, pineappl... more Pineapple (Ananas comosus L. Merr) is an economic horticultural crop in Uganda. However, pineapple production is currently being threatened by the latest outbreak of pineapple heart rot disease in Uganda. Yet, information on pineapple heart rot disease causal pathogen is unknown. Therefore, the objective of this study was to identify the pathogen causing pineapple heart rot disease (PHRD) in Uganda. Samples of pineapple leaves with symptoms of PHRD were collected from four districts of Masaka, Luwero, Mukono and Kayunga. Pathogen isolation was done using corn meal agar (CMA) amended with Pimaricin, Ampicillin, Rifampicin Pentachloronitrobenzene, Hymexazol and Benomyl (PARPHB). Macro- and micro- morphological characteristics of the isolates were assessed using Potato dextrose agar (PDA) and V8 media, respectively. Pathogenicity of the isolates was tested using healthy pineapple plants based on Koch’s postulate. The results showed a significant difference (P<0.05) in the growth rat...

African Journal of Biotechnology

Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and... more Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and are not known to colonize other environments. Xanthomonas colonize host parts such as leaves, stems and roots before entering vascular tissues and engaging in an invasive pathogenic phase. These bacterial strains have evolved strategies to adapt to life in this environment. The host-pathogen interactions of Xanthomonas vasicola (Xv) need to be well understood to properly map the target genes in the host and pathogen so as to understand the mechanism of resistance. Genotypic characterization, based on the analysis of restriction fragment length polymorphism of virulence factor fragment products was performed on members of the X. vasicola pv. musacearum (Xcm) and X. vasicola pv. vasculorum (Xvv) from varying geographical locations. The study showed that Xcm and Xvv are different from each other based on amplification of virulence factors within fragments of their DNA. Bacterial strains of similar species can have unique Type four pili (Tfp) and Tfp pilus assembly protein PilF a fimbrial biogenesis protein was amplified in all Xanthomonas strains except NCPPB1131 only. Type III effector protein RipT was confirmed to be present in all strains of Xcm and Xvv but not NCPPB1131 and NCPPB1132. All the Xcm and Xvv strains under test yielded bands of type III effector HopAF1 except Xvv206, NCPPB1131 and NCPPB1132. YopJ type III secretion system effector protein hybridizes in DNA of all Xcm strains tested but not in NCPPB1131 or NCPPB1132. This study confirmed the predicted presence or absence of virulence factors especially effectors across bacterial strains and within strains of the same species and other clusters conserved in gram negative bacteria.

African Journal of Biotechnology, Mar 22, 2017

Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and... more Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and are not known to colonize other environments. Xanthomonas colonize host parts such as leaves, stems and roots before entering vascular tissues and engaging in an invasive pathogenic phase. These bacterial strains have evolved strategies to adapt to life in this environment. The host-pathogen interactions of Xanthomonas vasicola (Xv) need to be well understood to properly map the target genes in the host and pathogen so as to understand the mechanism of resistance. Genotypic characterization, based on the analysis of restriction fragment length polymorphism of virulence factor fragment products was performed on members of the X. vasicola pv. musacearum (Xcm) and X. vasicola pv. vasculorum (Xvv) from varying geographical locations. The study showed that Xcm and Xvv are different from each other based on amplification of virulence factors within fragments of their DNA. Bacterial strains of similar species can have unique Type four pili (Tfp) and Tfp pilus assembly protein PilF a fimbrial biogenesis protein was amplified in all Xanthomonas strains except NCPPB1131 only. Type III effector protein RipT was confirmed to be present in all strains of Xcm and Xvv but not NCPPB1131 and NCPPB1132. All the Xcm and Xvv strains under test yielded bands of type III effector HopAF1 except Xvv206, NCPPB1131 and NCPPB1132. YopJ type III secretion system effector protein hybridizes in DNA of all Xcm strains tested but not in NCPPB1131 or NCPPB1132. This study confirmed the predicted presence or absence of virulence factors especially effectors across bacterial strains and within strains of the same species and other clusters conserved in gram negative bacteria.

Research Square (Research Square), Jun 6, 2022

Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa.... more Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa. To increase the production, substantial upgrading must be accomplished by enlarging the genetic potential of new cultivars that relays on the parents' genetic diversity. We aimed to assess the genetic diversity and the population structure of soybean accessions, therefore, evaluate soybean value in terms of use for breeding purposes. To accomplish this, a set of 282 soybean accessions were genotyped using the Diversity Array Technology Sequencing with a high throughput of the Single-nucleotide polymorphisms (SNPs). A total of 6,935 high-quality SNPs were identi ed across the whole soybean genome. The mean value of genetic diversity, major alleles frequency, minor alleles frequency, expected heterozygosity, and the polymorphism information content was respectively estimated at 0.35, 0.77, 0.22, 0.33, and 0.29. The analysis of molecular variance reveals that the variance among the populations is lower than the variance within the populations. The soybean accessions could be classi ed into two groups based on the model-based population structure and the principal coordinate analysis or into three groups based on the discriminant analysis of the principal component and the Neighbor-joining tree. The information provided in this study will be helpful for breeders.

Research Square (Research Square), Aug 1, 2022

Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa.... more Soybean (Glycine max (L.) is an important oil crop with production below the real need in Africa. To increase the production, substantial upgrading must be accomplished by enlarging the genetic potential of new cultivars that relays on the parents' genetic diversity. We aimed to assess the genetic diversity and the population structure of soybean accessions, therefore, evaluate soybean value in terms of use for breeding purposes. To accomplish this, a set of 282 soybean accessions were genotyped using the Diversity Array Technology Sequencing with a high throughput of the Single-nucleotide polymorphisms (SNPs). A total of 6,935 high-quality SNPs were identified across the whole soybean genome. The mean value of genetic diversity, major alleles frequency, minor alleles frequency, expected heterozygosity, and the polymorphism information content was respectively estimated at 0.35, 0.77, 0.22, 0.33, and 0.29. The analysis of molecular variance reveals that the variance among the populations is lower than the variance within the populations. The soybean accessions could be classified into two groups based on the model-based population structure and the principal coordinate analysis or into three groups based on the discriminant analysis of the principal component and the Neighbor-joining tree. The information provided in this study will be helpful for breeders.

International Journal of Environment, Agriculture and Biotechnology, 2018

Sorghum is the third most important staple cereal crop in Uganda after maize and millet. Downy mi... more Sorghum is the third most important staple cereal crop in Uganda after maize and millet. Downy mildew disease is one of the most devastating fungal diseases which limits the production and productivity of the crop. The disease is caused by an obligate fungus, Peronosclerospora sorghi (Weston & Uppal) with varying symptoms. Information on the genetic diversity and population structure of P.sorghi in sorghum is imperative for the screening and selection for resistant genotypes and further monitoring possible mutant(s) of the pathogen. Isolates of P. sorghi infecting sorghum are difficult to discriminate when morphological descriptors are used. The use of molecular markers is efficient, and reliably precised for characterizing P. sorghi isolates. This study was undertaken to assess the level of genetic diversity and population structure that exist in P. sorghi isolates in Uganda. A total of 195 P. sorghi isolates, sampled from 13 different geographic populations from 10 different regio...

African Journal of Biotechnology, 2009

The Random Amplification of Polymorphic DNA (RAPD) analysis was used to detect the genetic divers... more The Random Amplification of Polymorphic DNA (RAPD) analysis was used to detect the genetic diversity among Ugandan isolates of Xanthomonas campestris pv. musacearum (Xcm), the causal agent of banana Xanthomonas wilt (BXW) disease. Seven random primers were used because of their ability to amplify reproducible and reliable fingerprints generated between 6 - 12 amplicons each from the Xcm isolates obtained from central core of pseudostems, peduncles, fruit peelings, sap, nectar, insects’ bodies and bacterial oozes. Regardless of the source and geographical origin, similar fingerprints were generated from the tested isolates. Using a similarity coefficient of 58%, the unweighted pair group method with arithmetic averaging (UPGMA) analysis did not reveal any significant differences in clustering, with exception of a single isolate that had unique fingerprints. Prior to the genetic analysis, all the isolates compared showed no significant difference (P = 0.92) with regard to incubation p...

Journal of Plant breeding and Crop Science, 2017

Fusarium related root rots have been associated with reduced cowpea productivity in Uganda. Sourc... more Fusarium related root rots have been associated with reduced cowpea productivity in Uganda. Sources of genetic resistance to Fusarium redolens which was found to be the most virulent have been identified but the mode of inheritance of the genes conferring the resistance is unknown. This study aims to investigate how the genes for resistance to F. redolens are inherited in cowpea. Four F. redolens root rot resistant cowpea genotypes were crossed with four intermediately resistant and 2 susceptible cowpea genotypes using North Carolina mating design II. The F1 and the parents were evaluated and data were collected on resistance to seed rot, leaf chlorophyll amount, produced lateral roots, response to plant mortality and root rot severity. Results revealed that additive gene effects were significant for all evaluated traits and non-additive genetic effects were significant in resistance to seed rot and chlorophyll amount. General combining ability (GCA) effects showed that the Asontem ...

In 2014, researchers in Uganda spotted signs typical bacterial leaf streak disease (Xanthomonas o... more In 2014, researchers in Uganda spotted signs typical bacterial leaf streak disease (Xanthomonas oryzae pv. oryzicola) in rice fields in Eastern Uganda. The disease was later confirmed to be bacterial leaf streak. In order to effectively plan for measures to manage this potentially devastating disease, it was imperative to score rice germplasm in Uganda for reaction to Xoc. Eighty four genotypes from the National Rice Improvement program were evaluated for their reaction to BLS using two Xoc isolates collected from Namulonge and Iganga. These were inoculated by the infiltration method using a needless syringe 30 days after planting. Data were collected on the streak length induced by BLS on the leaves 15 days after inoculation. The mean streak length per genotype was interpreted as; Resistant (R), 030mm. Genotypes showed signficant variability (P Xoc isolates reacted signficantly differently (P=0.011) on the rice genotypes. For the Iganga isolate, 6 genotypes were resistant while 17 ...

International Journal of Environment, Agriculture and Biotechnology

African Journal of Agricultural Research

Many landraces and improved cultivars of sorghum (Sorghum bicolor) grown in Uganda have late matu... more Many landraces and improved cultivars of sorghum (Sorghum bicolor) grown in Uganda have late maturity and are susceptible to several biotic and abiotic stresses. Introgression of the rhizomatous trait from perennial sorghum (Sorghum halepense) could improve stress tolerance. However, phenotypic characterization of exotic perennial sorghum germplasm under Ugandan environmental conditions is essential to select desirable genotypes. Rhizome-forming capacity of 192 S. bicolor × S. halepense backcross tetraploid families developed in a temperate North American environment was evaluated at two locations in Uganda over two consecutive growing seasons. Numbers of rhizomes and emerging shoots as well as mean distances from shoot to crown were evaluated. Forty-seven percent of families were moderately to strongly rhizomatous in the first season of growth and this value rose to 91% in the second season. Developing perennial grain sorghum for East Africa will require hybridization between exotic perennial and locally adapted germplasm. Screening for emerging rhizome-derived shoots in early generations is simple, rapid, and effective; however, more detailed selection based on both aboveground and belowground rhizome traits is recommended for later generations. Researchers and farmers should work together to find suitable ways in which perennial sorghum might fit into new types of crop and livestock systems.

International Journal of Advanced Research

Sorghum (Sorghum bicolor) ranks as the third most important staple cereal food crop in Uganda aft... more Sorghum (Sorghum bicolor) ranks as the third most important staple cereal food crop in Uganda after maize and millet. The crop is hampered by several biotic stresses of which Sorghum Downy Mildew disease is one of the most devastating diseases. The disease is caused by a soil-borne fungus Peronosclerospora sorghi but it is also airborne through conidia. Incidence and severity of downy mildew were conducted between March-June, 2016 and September-December 2016 growing seasons in 13 sorghum-growing districts across ten agroecological zones. Data collected were subjected to analyses of variance, correlation and linear regression. Significant (P < 0.001) differences were recorded for disease incidence and severity across the different agro-ecologies. The mean downy mildew disease incidence varied significantly (P< 0.001) from 49.4 % for Pader to 78.9 % for Namutumba. Disease severity varied significantly (P <0.001) from 2.3 for Pader to 3.5 for Pallisa. Chi-square test for independent association between cropping season and downy mildew disease incidence showed a high significant test statistic values (χ2 = 140.89, d.f = 3, and P < 0.001). A significant (P<0.001) positive correlation was observed between disease incidence and severity (r = 0.498) while a significant negative correlation was observed between disease incidence and rainfall (r =-0.675) due largely to temperature and relative humidity. Multiple linear regression analysis revealed that temperature, relative humidity, rainfall and altitude explained 49 % of the total variation associated to disease incidence. Variations in the incidence and severity of downy mildew disease prompt the need to screen for resistant/tolerant sorghum varieties.

International Journal of Phytopathology

Pineapple (Ananas comosus L. Merr) is an economic horticultural crop in Uganda. However, pineappl... more Pineapple (Ananas comosus L. Merr) is an economic horticultural crop in Uganda. However, pineapple production is currently being threatened by the latest outbreak of pineapple heart rot disease in Uganda. Yet, information on pineapple heart rot disease causal pathogen is unknown. Therefore, the objective of this study was to identify the pathogen causing pineapple heart rot disease (PHRD) in Uganda. Samples of pineapple leaves with symptoms of PHRD were collected from four districts of Masaka, Luwero, Mukono and Kayunga. Pathogen isolation was done using corn meal agar (CMA) amended with Pimaricin, Ampicillin, Rifampicin Pentachloronitrobenzene, Hymexazol and Benomyl (PARPHB). Macro- and micro- morphological characteristics of the isolates were assessed using Potato dextrose agar (PDA) and V8 media, respectively. Pathogenicity of the isolates was tested using healthy pineapple plants based on Koch’s postulate. The results showed a significant difference (P<0.05) in the growth rat...

African Journal of Biotechnology

Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and... more Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and are not known to colonize other environments. Xanthomonas colonize host parts such as leaves, stems and roots before entering vascular tissues and engaging in an invasive pathogenic phase. These bacterial strains have evolved strategies to adapt to life in this environment. The host-pathogen interactions of Xanthomonas vasicola (Xv) need to be well understood to properly map the target genes in the host and pathogen so as to understand the mechanism of resistance. Genotypic characterization, based on the analysis of restriction fragment length polymorphism of virulence factor fragment products was performed on members of the X. vasicola pv. musacearum (Xcm) and X. vasicola pv. vasculorum (Xvv) from varying geographical locations. The study showed that Xcm and Xvv are different from each other based on amplification of virulence factors within fragments of their DNA. Bacterial strains of similar species can have unique Type four pili (Tfp) and Tfp pilus assembly protein PilF a fimbrial biogenesis protein was amplified in all Xanthomonas strains except NCPPB1131 only. Type III effector protein RipT was confirmed to be present in all strains of Xcm and Xvv but not NCPPB1131 and NCPPB1132. All the Xcm and Xvv strains under test yielded bands of type III effector HopAF1 except Xvv206, NCPPB1131 and NCPPB1132. YopJ type III secretion system effector protein hybridizes in DNA of all Xcm strains tested but not in NCPPB1131 or NCPPB1132. This study confirmed the predicted presence or absence of virulence factors especially effectors across bacterial strains and within strains of the same species and other clusters conserved in gram negative bacteria.

African Journal of Biotechnology, Mar 22, 2017

Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and... more Bacterial plant pathogens belonging to the Xanthomonas genus are adapted to their host plants and are not known to colonize other environments. Xanthomonas colonize host parts such as leaves, stems and roots before entering vascular tissues and engaging in an invasive pathogenic phase. These bacterial strains have evolved strategies to adapt to life in this environment. The host-pathogen interactions of Xanthomonas vasicola (Xv) need to be well understood to properly map the target genes in the host and pathogen so as to understand the mechanism of resistance. Genotypic characterization, based on the analysis of restriction fragment length polymorphism of virulence factor fragment products was performed on members of the X. vasicola pv. musacearum (Xcm) and X. vasicola pv. vasculorum (Xvv) from varying geographical locations. The study showed that Xcm and Xvv are different from each other based on amplification of virulence factors within fragments of their DNA. Bacterial strains of similar species can have unique Type four pili (Tfp) and Tfp pilus assembly protein PilF a fimbrial biogenesis protein was amplified in all Xanthomonas strains except NCPPB1131 only. Type III effector protein RipT was confirmed to be present in all strains of Xcm and Xvv but not NCPPB1131 and NCPPB1132. All the Xcm and Xvv strains under test yielded bands of type III effector HopAF1 except Xvv206, NCPPB1131 and NCPPB1132. YopJ type III secretion system effector protein hybridizes in DNA of all Xcm strains tested but not in NCPPB1131 or NCPPB1132. This study confirmed the predicted presence or absence of virulence factors especially effectors across bacterial strains and within strains of the same species and other clusters conserved in gram negative bacteria.