A5020380457- Plant Virus Research Studies
- Plant Pathogenic Bacteria Studies
- Nematode management and characterization studies
- Insect-Plant Interactions and Control
- Cassava research and cyanide
- Mosquito-borne diseases and control
- Cocoa and Sweet Potato Agronomy
- Agricultural pest management studies
- Insect symbiosis and bacterial influences
- Plant and Fungal Interactions Research
- CRISPR and Genetic Engineering
- Banana Cultivation and Research
- Genetic and Environmental Crop Studies
- Plant-Microbe Interactions and Immunity
- Agronomic Practices and Intercropping Systems
- Plant Disease Resistance and Genetics
- Genetics and Plant Breeding
- Plant Pathogens and Fungal Diseases
- Plant tissue culture and regeneration
- Genetic Mapping and Diversity in Plants and Animals
- Transgenic Plants and Applications
- Weed Control and Herbicide Applications
- Evolution and Genetic Dynamics
- Papaya Research and Applications
- Insect Pest Control Strategies
Tropical Pesticides Research Institute
2023-2025
Mikocheni Agricultural Research Institute
2012-2024
Nelson Mandela African Institution of Science and Technology
2016-2024
University of Dar es Salaam
2022
University of Pretoria
2005
Donald Danforth Plant Science Center
2003-2005
Tanzania National Parks
2000
University of Zambia
1996-1998
Cassava (Manihot esculenta) provides calories and nutrition for more than half a billion people. It was domesticated by native Amazonian peoples through cultivation of the wild progenitor M. esculenta ssp. flabellifolia is now grown in tropical regions worldwide. Here we provide high-quality genome assembly cassava with improved contiguity, linkage, completeness; almost 97% genes are anchored to chromosomes. We find that paleotetraploidy shared related rubber tree Hevea, providing resource...
Abstract Bemisia tabaci whitefly species are some of the world’s most devastating agricultural pests and plant-virus disease vectors. Elucidation phylogenetic relationships in group is basis for understanding their evolution, biogeography, gene-functions development novel control technologies. We report here discovery five new Sub-Saharan Africa (SSA) B . putative species, using partial mitochondrial cytochrome oxidase 1 gene: SSA9, SSA10, SSA11, SSA12 SSA13. Two them, SSA10 SSA11 clustered...
Cassava brown streak disease is caused by two devastating viruses, virus (CBSV) and Ugandan cassava (UCBSV) which are frequently found infecting cassava, one of sub-Saharan Africa's most important staple food crops. Each year these viruses cause losses up to $100 million USD can leave entire families without their primary source, for an year. Twelve new whole genomes, including seven CBSV five UCBSV were uncovered in this research, doubling the genomic sequences available public domain...
In this case study we successfully teamed the PDQeX DNA purification technology developed by MicroGEM, New Zealand, with MinION and MinIT mobile sequencing devices Oxford Nanopore Technologies to produce an effective point-of-need field diagnostic system. The extracts using a cocktail of thermophilic proteinases cell wall-degrading enzymes, thermo-responsive extractor cartridges temperature control unit. This closed system delivers purified no cross-contamination. is newly released data...
Abstract Cassava is a major staple food for about 800 million people in the tropics and sub-tropical regions of world. Production cassava significantly hampered by brown streak disease (CBSD), caused virus (CBSV) Ugandan (UCBSV). The suppressing yields eastern Africa at an alarming rate. Previous studies have documented that CBSV more devastating than UCBSV because it readily infects both susceptible tolerant cultivars, resulting greater yield losses. Using whole genome sequences from NGS...
Abstract Cassava is infected by numerous geminiviruses in Africa and India that cause devastating losses to poor farmers. We here describe the molecular diversity of seven representative cassava mosaic (CMGs) infecting from multiple locations Tanzania. report for first time presence two isolates East Africa: (EACMCV-[TZ1] EACMCV-[TZ7]) species African Cameroon virus , originally described West Africa. The complete nucleotide sequence EACMCV-[TZ1] DNA-A DNA-B components shared a high overall...
Abstract Background Plant viral diseases present major constraints to crop production. Effective sampling of the viruses infecting plants is required facilitate their molecular study and essential for development protection improvement programs. Retaining integrity pathogens within sampled plant tissues often a limiting factor in this process, most especially when sample sizes are large operating developing counties regions remote from laboratory facilities. FTA paper-based system designed...
Abstract The genetic variability of whitefly ( B emisia tabaci ) species, the vectors cassava mosaic begomoviruses CMB s) in growing areas K enya, T anzania, and U ganda, was investigated through comparison partial sequences mitochondria cytochrome oxidase I (mt COI DNA 2010/11. Two distinct species were obtained including sub‐ S aharan A frica 1 SSA 1), comprising two sub‐clades (I II ), a outh W est ndian O cean Islands SWIO species. Among 1, sub‐clade shared similarity 97.8–99.7% with...
Cassava brown streak disease (CBSD) and cassava mosaic (CMD) are two viral diseases that cause severe yield losses in of up to 100%, thereby persistently threatening food income security sub-Saharan Africa. For effective management these diseases, there is a critical need develop deploy varieties with dual resistance CBSD CMD. In this study, we determined the response advanced breeding lines field infection by viruses (CBSVs) begomoviruses (CMBs). This aim helped identifying superior clones...
Abstract High starch yield is the most important trait for commercialized cassava production. Furthermore, cyanide present in roots poses a health challenge use of food. Cassava genotypes have varying maturity periods that are also environmental dependent. This study aimed at identifying suitable cultivars and optimum time harvest to maximize production across three environments. The found significant difference between genotypes, locations, period, all interactions ( P ≤ 0.001) traits...
Cassava is the main staple food for over 800 million people globally. Its production in eastern Africa being constrained by two devastating Ipomoviruses that cause cassava brown streak disease (CBSD); virus (CBSV) and Ugandan (UCBSV), with up to 100% yield loss smallholder farmers region. To date, vector studies have not resulted reproducible highly efficient transmission of CBSV UCBSV. Most used Bemisia tabaci (whitefly), but a maximum 41% U/CBSV efficiency has been documented this vector....
ABSTRACT Cassava mosaic begomoviruses (CMBs) cause cassava disease (CMD) across Africa and the Indian subcontinent. Like all members of geminivirus family, CMBs have small, circular single-stranded DNA genomes. We report here discovery two novel sequences, designated SEGS-1 SEGS-2 (for s equences e nhancing g eminivirus ymptoms), that enhance symptoms break resistance to CMD. The SEGS are characterized by GC-rich regions absence long open reading frames. Both enhanced CMD in ( Manihot...
<ns4:p>Crop losses due to viral diseases and pests are major constraints on food security income for millions of households in sub-Saharan Africa (SSA). Such can be reduced if plant correctly diagnosed identified early. Currently, accurate diagnosis definitive identification viruses their vectors SSA mostly relies standard PCR next generation sequencing technologies (NGS). However, it take up 6 months before results generated using these approaches available. The long time taken detect or...
Cassava brown streak disease (CBSD) was first observed on cassava ( Manihot esculenta ) in Rwanda 2009. In 2014 eight major cassava‐growing districts the country were surveyed to determine distribution and variability of symptom phenotypes associated with CBSD, genetic diversity viruses. Distribution CBSD their combinations varied greatly between districts, cultivars The symptoms leaf alone recorded highest (32.2%) incidence, followed by roots (25.7%), + stem (20.3%), root (10.4%), (5.2%),...
Abstract Background Cassava leaf samples degrade quickly during storage and transportation from distant areas. Proper sampling efficient, low-cost methods are critical for obtaining sufficient quality DNA RNA plant virus epidemiology improving disease control understanding. This is useful when collected remote areas far a laboratory or in developing countries where money materials diagnostics scarce. Results The effect of sample duration on nucleic acid (N.A.) detection was investigated this...
Cassava varieties resistant to cassava mosaic disease (CMD) and brown streak (CBSD) are needed for the food income security of rural poor in eastern southern Africa (ESA). The International Institute Tropical Agriculture led five national breeding programs (Malawi, Mozambique, Kenya, Tanzania Uganda) virus-cleaning exchanging elite germplasm both diseases. This paper documents experiences lessons learned from process. Thirty-one clones (25 elite, two standard four national) were submitted by...
Cassava brown streak disease (CBSD) is currently the most devastating cassava in eastern, central and southern Africa affecting a staple crop for over 700 million people on continent. A major outbreak of CBSD 2004 near Kampala rapidly spread across Uganda. In following years, similar outbreaks were noted countries eastern Africa, now poses threat to West including Nigeria - biggest producer world. comprehensive dataset with 7,627 locations, annually consistently sampled between 2017 was...
Cassava is an important root crop that produced by smallholder farmers across Sub-Saharan Africa. mosaic disease (CMD), which caused a group of cassava begomoviruses (CMBs), one the most devastating diseases cassava. A previous study showed SEGS-1 (sequences enhancing geminivirus symptoms), occur both in genome and as episomes during CMD, can increase CMD severity overcome host resistance. In this report, we examined effects exogenously applied on incidence CMB infection, symptom severity,...