ABSTRACT The existence of genetic diversity in germplasm collections is crucial for cultivar development. The objectives of this study were to determine genetic diversity of bambara groundnut (Vigna subterranea (L) Verdc.) landraces from Kenya using genetic markers and characterize bambara groundnut landraces from Kenya using morphological markers. Genetic and morphological relationships among bambara groundnuts accessions, were evaluated using morphological and microsatellite markers. Twelv...
ABSTRACT Sweet sorghum [Sorghum bicolor (L). Moench] is important for production of fodder and ethanol worldwide. Objectives of this study were to determine: (i) the most suitable harvesting stage for sweet sorghum for which ethanol production is a maximum, (ii) the combining abilities for ethanol related traits and (iii) the best sweet sorghum hybrids for production of industrial alcohol. Experiments were conducted in Nakuru (0° 23′S, 35° 35′E), Homa Bay (0.35o 13′07′′S, 34o 07�...
ABSTRACT Morphological and genetic diversity are important components for cultivar development and are a pre-requisite to cultivar improvement. The probability of producing unique genotypes increases in proportion to the number of genes for which parents differ (genetic distance). The objectives of this study were to determine the morphological and genetic diversity among native blackberry (Rubus L. subgenus Rubus Watson) accessions in selected counties in Kenya and their relationship with P...
ABSTRACT Stem rust (Puccinia graminis f. sp. tritici) is one of the most important diseases of wheat (Triticum aestivum L.) and is known to cause major wheat yield losses in Kenya as well as other wheat growing countries of Africa and Asia. The present study aimed at; i) determining seedling, adult plant resistance and yield of 64 advanced wheat breeding lines, and ii) estimating the kind of gene action in inheritance of adult plant resistance to stem rust and yield components in a 6 6 diall...
ABSTRACT Leaf rust (Puccinia triticina) of wheat (Triticum aestivum L.) is one of the major foliar diseases contributing to yield losses in wheat worldwide. Objectives of this study were: (i) to determine genotypic variation among Kenyan wheat genotypes against leaf rust at adult plant stage (ii) to determine genotypic variation among Kenyan wheat genotypes against leaf rust at seedling stage (iii) to determine leaf rust virulence in Kenya using leaf rust differential sets. Three experiments...
ABSTRACT Stem rust of wheat (Triticum aestivum L.) caused by Puccinia graminis f.sp. tritici had been controlled globally through the use of resistant varieties. However, the emergence of a new and more virulent race Ug99 (designated TTKSK) and its variants reversed these gains. The objectives of this study therefore were: to assess the progress in using adult plant resistance (APR) in controlling stem rust in CIMMYT wheat lines and to evaluate CIMMYT wheat lines for seedling and adult plant ...
Thirty-one cowpea genotypes from 2000 planting season of derived savanna ecology to determine the genetic diversity, using multivariate analysis. In four location - season environments twenty cultivars were grown to measure genotype x environment interaction and stability. Data were collected on gronomic and yield characters. The first three axes of the Principal Component Analysis (PCA) captureJ 40. 7% or the total variation among the enteries. lleight at flowering and maturity, length ...
ABSTRACT Vegetable amaranths are highly valued for being rich in proteins and micronutrients such as iron, calcium, zinc, vitamin C and vitamin A. In spite of the crop’s exceptional nutritional qualities, very little effort has been put in to improve the foliage yield potential in Kenya. Reports on morphological phenotypic variation analysis in Amaranthus are rare and detailed agronomic recommendations for leaf and seed yields and quality enhancement are scanty. Research on the extent of th...
ABSTRACT Declining soil fertility in general and nitrogen (N) in particular limit crop production on many smallholder farms in western Kenya. Soil N deficiency is usually ameliorated with inorganic N fertilizers but their high costs preclude their use by resource poor smallholder farmers. In addition there are concerns that increased use of inorganic fertilizers could lead to environmental degradation. Organic inputs offer sustainable alternatives to expensive inorganic N fertilizers but the ...
ABSTRACT The obligate root hemi-parasite, Striga hermonthica (Del.) Benth., native to sub-Saharan Africa causes serious economic constraint to cereal production. There has been limited study to understand the genetics of Striga tolerance or resistance in maize in Kenya and the information on mechanisms of resistance to Striga in maize in very limited. T he use of maize ( Zea mays L.) genotypes that support reduced Striga hermonthica emergence can form an important basis for developing Striga ...
ABSTRACT End-of-season drought, characterized by low and erratic rainfall, is the most important factor limiting groundnut (Arachis hypogaea L.) production in Niger. Information about farmers' varietal preferences and production constraints are limited. Genotypes have not yet been screened for earliness and tolerance to end-of-season drought. Data on combining ability and heritability estimates are not available. Development of varieties that have better ability to use limited available water...
ABSTRACT Maize is increasingly consumed by Nigerien households. Limited studies have been conducted on the production and productivity of this crop in Niger and very few cultivars (mostly open pollinated varieties) are available to farmers. Knowledge and understanding of farmers’ preferences for new varieties would be invaluable in designing a successful maize breeding program. Maize cultivars grown in Niger are derived mainly from tropical yellow-grained extra-early and early-maturing lowl...
ABSTRACT Solanum aethiopicum is one of the most important Solanum species, with four morphological groups. Two of the groups, Gilo and Shum, are mainly cultivated because of their nutritional value and income generating potential for farmers in developing countries. Of focus for this study was the Shum, a leafy morphological group whose productivity and quality is directly affected by drought. Global limitations on water resource availability call for the need to develop productive varieties ...
ABSTRACT Sorghum panicle architecture is a complex trait involving growth, elongation and branching pattern. The main objective of this research was to determine the genetic control of sorghum panicle architecture and its involvement in grain yield. Molecular markers associated with statistical analyses were used to identify the genomic regions or QTLs controlling quantitative traits. A population composed of 401 F4 families was derived from a cross between two contrasted parents for panic...
ABSTRACT Chickpea is an important legume crop in the arid and semi-arid lands (ASALs). It is commonly grown during the post-rainy season under receding soil moisture conditions. This exposes the crop to drought especially terminal drought which occurs towards the end of the cropping period, causing high yield losses. Developing drought tolerant and high yielding chickpea genotypes, incorporating farmer prefer traits, is an important goal for plant breeders in the ASALs for increased productiv...