Browsing by Author "Feyissa, Tileye"

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Genetic diversity of grapevine (Vitis vinifera L.) from Tanzania as revealed by ISSR markers
(Journal of Advances in Agriculture, 2015-10-19) Mwamahonje, Andekelile; Kilambo, Deusdedit; Mrosso, Leon; Feyissa, Tileye
Grapevine (Vitis viniferaL.) is a perennial horticultural crop which is used worldwide for production of wine, table grapes, dried fruits and grape juice. In spite of its importance as a cash crop, the purity of each variety and genetic diversity of this crop has not been identified. The study therefore, was conducted to assess the purity and genetic diversity among and within 10 varieties of grapevines represented by a total of 43 individual plants. By using nine ISSR primers, a total of 56 polymorphic bands were generated. Within variety diversity based on polymorphic bands ranged from 26.79% for Ruby seedless to 73.21% for Alphonce lavallee with a mean of 55.18 %, Nei’s genetic diversity of 0.089–0.308 with a mean of 0.202, Shannon information index of 0.137–0.445 with a mean of 0.302 and analysis of molecular variation (AMOVA) of 76.767% within varieties were detected. With all diversity parameters, the highest diversity was obtained from Regina, Alphonce lavallee, Syrah and Makutupora white varieties, whereas the lowest was from Ruby seedless. AMOVA showed a 23.23% between varieties variability was less than that of within varieties variation. Varieties differentiation with Fixation index (FST) was 0.23. From Jaccard’s pairwise similarity coefficient, Makutupora red and Chancellor were most related varieties exhibiting 0.976 meanwhile Queen of vineyard and Ruby seedless were most distantly related varieties with similarity of 0.408. Alphonce lavallee and Makutupora white varieties exhibited the highest genetic diversity. Therefore, these varieties should be considered for further improvement of this species.
Genetic Diversity of Jute Mallow (Corchorus spp.) Accessions Based on ISSR Markers
(Scientific Research Publishing Inc, 2024-05-21) Ngomuo, Munguatosha; Stoilova, Tsvetelina; Feyissa, Tileye; Ndakidemi, Patrick
Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation.
The genetic diversity of leaf vegetable jute mallow (Corchorus spp.): A review
(Indian Journal of Agricultural Research, 2017-09-27) Ngomuo, Munguatosha; Stoilova, Tsvetelina; Feyissa, Tileye; Kassim, Neema; Ndakidemi, Patrick
Corchorus spp. is among traditional vegetable which is very nutritious and has been in use in many households in Africa. It contains high level of carotenoids (150μg/100g), vitamin C, Iron (190μg/g), 1.3% Calcium and 25.0% protein. The leaves are used in treatment of diseases and have wide antibacterial properties. It is semidomesticated and sometimes grows as a volunteer crop. Its status in some parts of Tanzania as a wild plant renders it unappealing for consideration in crop development programs.There is limited scientific information on its diversity for use as a vegetable in crop improvement and is a potential area for research. Variations exist among different accessions based on leaf shapes and color. Diversity studies by using molecular markers, proteins and isozymes are reported by several authors. There is low variation within species and high among species. Most of released varieties have a narrow genetic base. Conservation of this species in Africa is scarcely reported.
In Vitro Callus Induction and Shoot Regeneration from Leaf Explants of Glinus lotoides (L.)—An Important Medicinal Plant
(Scientific Research Publishing Inc., 2015-06-05) Teshome, Shiferaw; Feyissa, Tileye
G. lotoides L. is a threatened plant that is frequently harvested for medicinal purpose. However, its distribution in the world is limited because of short period of seed viability and poor seed germination. The objective of this study was to develop in vitro propagation protocol for G. lotoides through callus induction. For callus induction, different concentrations of 2,4-D (2,4-dichlorophenoxyacetic acid), NAA (α-naphthalene acetic acid) and BAP (6-benzyl amino purine) were used. Seeds were sown on growth regulator-free MS medium and shoots from the in vitro germinated seedlings were excised and cultured on MS medium containing 0.5 mg/l BAP. Young leaves from these shoots were used as explant for callus induction and shoot regeneration. Maximum callus induction (100%) was observed on medium containing 2,4-D (0.5, 2.0, 3.5 mg/l) or NAA (2.0, 2.5 mg/l) in combination with 0.5 mg/l BAP. However, 2,4-D was the best in overall callus induction. The highest regeneration (20%) frequency was achieved on the medium containing 0.5 mg/l BAP. Highest number of shoot (2.83 ± 1.22) and shoot length (2.16 ± 0.87 cm) per explant were obtained in the presence of 0.25 mg/l BAP + 0.5 mg/l KIN (Kinetin). In shoot multiplication media, maximum mean (6.43 ± 0.87) of shoot was observed on MS medium containing 0.5 mg/l BAP. The best shoot length (1.70 ± 0.14 cm) was recorded on control medium. The highest (95%), maximum root number (14.10 ± 1.47) and root length (1.01 ± 0.10 cm) were obtained on a medium supplemented with 1.5 mg/l Indole-3-butyric acid (IBA). All the plants (100%) were survived after acclimatization in greenhouse. The present study can be useful for callus induction and indirect shoot regeneration form G. lotoides.
Leaf and seed yield of jute mallow (Corchorus olitorius L.) accessions under field conditions for two consecutive growing seasons
(Taylor & Francis Group, 2017-04-11) Ngomuo, Munguatosha; Stoilova, Tsvetelina; Feyissa, Tileye; Kassim, Neema; Ndakidemi, Patrick
Jute mallow is a nutritious leafy vegetable used by many people in Africa. The purpose of this study was to select accessions with high leaf yield and seed yield. We investigated seven agronomic traits that are related to leaf yield and seed yield and how they correlate with each other. The results indicated significant differences among the accessions in all traits. Leaf fresh weight ranged from 18.3 to 121.3 g/plant in accessions TOT 6747 and TOT 8532, respectively. The highest variability between the accessions was also observed in seed yield. It ranged from 1.0 g/plant in accession TOT 7980 to 35.5 g/plant in TOT 7866. Eight other accessions had a seed yield of 1.0 g/plant. Significant and positive correlations were observed between leaf fresh weight and leaf dry weight (r = 0.84), leaf area (r = 0.33), and number of leaves (r = 0.40). A significant correlation was observed in seed yield and weight of pods per plant (r = 0.83). The evaluation of these agronomic traits for leaf and seed yield in this germplasm has revealed useful information for breeders in their efforts to improve the yield as well as selection of accessions with good agronomic traits.
Molecular Genetic Diversity of Grapevines to Produce Powdery mildew Resistant Genotypes
(American Journal of Research Communication, 2015) Mwamahonje, Andekelile; Kilambo, Deusdedit; Feyissa, Tileye
Grapevine powdery mildew is a fungal disease caused by Erysiphe necator (formerly Uncinula necator) which is an obligate parasite. It is considered to be one of the most important fungal diseases in viticulture worldwide causing 20% loss of grapevine production. Conventional breeding has been used to obtain powdery mildew resistant varieties however; it takes long time to obtain new variety. The use of molecular markers has been proposed to be the best method for identifying genes for resistance to powdery mildew which provides basic information in breeding programs. Furthermore, molecular markers have been useful in identifying genetic diversity among grapevine varieties. Inter Simple Sequence Repeat (ISSR) and Simple Sequence Repeat (SSR) is among the most useful markers for genetic diversity studies. This will be among of the useful markers as the guidelines for breeding programs of grapevine in tropical and sub-tropical countries to improve agricultural production in addressing food security.
Prospects of Biotechnological Approaches for Propagation and Improvement of Threatened African Sandalwood (Osyris lanceolata Hochst. & Steud.)
(Scientific Research Publishing Inc., 2015-07-26) Xavery, Dickson Kalabamu; Feyissa, Tileye
The African Sandalwood plant (Osyris lanceolata ) is a threatened shrub or a small hemi-parasitic tree endemic to East Africa and South African regions, which is being severely affected by uprooting for oil extraction, poor natural regeneration, phenological structures (dioecious), medicinal values, lack of sexual recruitment, habitat loss, anthropogenic and climate factors. It has been found that through application of in situ conservation of natural trees with respect to rapid human population growth, the available natural strands of valuable plants such as African sandalwood have not been able to meet the demands of the people in world specifically developing countries. However, advances in plant biotechnology provide new options for collection, multiplication and short- to long-term conservation of Osyris lanceolata species, using in vitro culture techniques. Different aspects of biotechnological applications can be extensively used to reduce the risk of extinction of this valuable plant species and to improve the quality and quantity of essential oils produced by it. Therefore, tissue culture appears to be a promising approach for the propagation and conservation of African sandalwood plant.
Prospects of Biotechnology in Grape Breeding
(Journal of Advances in Agriculture, 2015-10-19) Mwamahonje, Andekelile; Kilambo, Deusdedit; Mrosso, Leon; Feyissa, Tileye
Genetic improvement of grape cultivars to obtain high quality wine and table grape varieties by conventional breeding methods has been difficult and time consuming. The elite grape varieties developed by conventional breeding techniques have less resistance to fungal and bacterial diseases, drought, quality and yield per plant. Breeding programs of grapes are difficult due to lack of true bred from seed and few traits of importance. Though most grapes constitute large number of genes, they have less effect in tolerating biotic and abiotic stresses. Genetic improvement of grapevine (Vitis vinifera L.) through application of biotechnological techniques provide new strategies in grape breeding programs based on rapid selection or induction of desired traits by marker assisted breeding, genetic engineering and plant tissue culture. This review paper therefore, aims to discuss biotechnological techniques proposed for improvement of grape breeding.
Quantifying the Occurrence and Ameliorating the Properties of Non-responsive Soils by Inorganic and Organic Fertilizers
(International Journal of Plant & Soil Science, 2015-11-30) Assenga, Onesmo; Feyissa, Tileye; Ndakidemi, Patrick
Conventionally, crop production in sub-Saharan Africa (SSA) depends primarily on natural soil nutrients. Application of inorganic and organic fertilizers is an important way for maximizing agriculture in SSA that targets the full utilization of the agricultural lands for food to feed African population and to obtain surplus produces. However, it has been reported that several areas of agricultural soils fail to respond to application of fertilizers, but the specific reason remain unknown. This review paper aims at exploring techniques that can be used to amend non-responsive soils and evaluate methods of ameliorating such soils through the proper utilization of nutrients supplied from different organic and inorganic sources.
Screening for resistance of grape varieties to powdery mildew (Erysiphe necator) disease
(Journal of Advances in Agriculture, 2015-10-20) Mwamahonje, Andekelile; Kilambo, Deusdedit; Mrosso, Leon; Feyissa, Tileye
This study was conducted to evaluate the susceptibility of grapevine varieties to powdery mildew. Powdery mildew is a disease caused by a fungal, Erysiphe necator, and an obligate parasite of grapevine (Vitis vinifera L.). Powdery mildew causes drastic yield losses of 50 to 70%. Commercial grapevines grown in producing countries are susceptible to powdery mildew. Use of fungicides to control the disease is expensive and not environmentally friendly. Therefore, use of grapevine resistant varieties to powdery mildew is cost-effective control method. In this study, ten varieties (Black rose, Regina, Queen of Vineyards, Alphonce lavallee, Makutupora red, Chancellor, Halili belyji, Syrah, Ruby seedless and Makutupora white) were screened for resistance to powdery mildew, using artificial inoculation of spore suspension and dry inoculums. Infected grape leaves were sampled from the field and grounded to obtain powder which was used as dry inoculum. The spore suspension inoculum was made by mixing powder with sterilized distilled water. The inoculation was done in two blocks with concentration of 2x105 spore/ml. Disease severity was evaluated based on a scale of 0 – 5; 0, means immune and 5, high level of disease severity. Results showed significant difference (P<0.05) of disease among grapevine varieties evaluated. It was found that 11.1% were resistant, 33.4% tolerant and 55% susceptible to disease. Grapevine variety Chancellor showed the highest level of resistance, and Black rose the most susceptible. The study demonstrates the effectiveness of using inoculation methods in screening resistance to powdery mildew.