Estimation of heterosis and combining ability in maize (Zea mays L.) for maize lethal necrosis (MLN) disease
September 2017
Nature of gene action and genetic parameters for disease resistance are important attributes in developing resistant cultivars. This provides the sustainable, economically justifiable and environmentally friendly means of controlling plant diseases. In this study 6 x 6 full diallel cross involving genetically divergent maize inbred lines was performed with the aim of developing resistant cultivars against Maize Lethal...
Agronomic performance evaluation of cowpea [Vigna unguiculata (L.) Walp] varieties in Abergelle District, Northern Ethiopia
August 2017
Cowpea (Vigna unguiculata L.) is one of the most important grain legumes in the semi-arid regions of many African countries including Ethiopia. However, it is less cultivated and scarcely distributed pulse crop in Abergelle due to a lack of improved varieties. A field experiment was conducted during the 2014 and 2015 main cropping seasons using a randomized complete block design with three replications to evaluate seven...
Introgresion of the SH3 gene resistant to rust (Hemileia vastatrix) in improved lines of CASTILLO® variety (Coffea arabica L.)
August 2017
The genetic improvement at Cenicafé has developed varieties with resistance to Coffee Leaf Rust (CLR) (Hemileia vastatrix) derived from the Timor Hybrid. These varieties have durable rust resistance, especially against race II, the predominant race. In Colombia, these varieties have been cultivated for three decades and still show resistance. Recently, new rust races have appeared attacking these varieties....
Morphological distinctiveness between Solanum aethiopicum Shum group and its progenitor
August 2017
Use of morphological markers offers an alternative in germplasm discrimination of research-neglected crop species. A collection of 25 accessions including five wild progenitors was evaluated in screen house to identify the morphological difference between Solanum aethiopicum Shum and Solanum anguivi. An Unweighted Pair Group Method with Arithmetic mean hierarchical clustering revealed presence of moderate structure with...
Cocoa floral phenology and pollin ation: Implications for productivity in Caribbean Islands
July 2017
Cocoa midges [Forcipomyia sp (Diptera: Cerato-pogonidae)] are major pollinators of cocoa and it is assumed that the number of fertilized pods and the increase in bean numbers may be the approach to enhancing cocoa yield. An insect survey using suction traps was employed to estimate the midge population dynamics in three Caribbean territories. Separate studies were conducted on the cocoa floral and reproductive phenology...
Reaction of introduced Korean rice genotypes for resistance to rice blast in Uganda
July 2017
Rice blast caused by Magnaporthe grisea is an economically important disease which distributed in most rice growing areas of the world. Yield losses up to 100% are attributed to the blast disease in different rice growing regions of Uganda. In order to combat this disease screening of forty-six introduced Korean rice accessions and two checks IR-64 (resistant) and NERICA-1 (susceptible) were done in a 6 by 8 alpha...
Diallel analysis of cowpea populations for resistance to Cowpea aphid-born mosaic virus disease (CABMV) in Burkina Faso
July 2017
Cowpea aphid-born mosaic virus disease (CABMV) is one of the reasons for rejection of cowpea seed by seed inspectors in Burkina Faso. With regard to this, this study was undertaken to analyze the genetic components underlying the resistance of cowpea lines to the cowpea aphid-borne mosaic virus (CABMV) and to determine the mechanism of transmission of the resistance from parents to offspring. Therefore, crosses were...
Variation in the susceptibility of okra (Abelmoschus esculentus L. Moench) genotypes to okra mosaic virus and Podagrica species under field conditions
June 2017
A total of 21 okra (Abelmoschus escuentus L. Moench) genotypes were screened for their reactions against okra mosaic disease (OMD) and flea beetles (Podagrica species) infestations in field trials which were conducted from May to October, 2015 (wet season) and November 2015 to March 2016 (dry season), in order to identify sources of resistance and or tolerance. The trials were laid out in a randomised complete block...
Inheritance of resistance to common bacterial blight in four selected common bean (Phaseolus vulgaris L.) genotypes
June 2017
Common bacterial blight (CBB) is the most serious bacterial disease of common bean in Uganda. It causes severe yield losses of up to 62%. Genetic resistance is the most effective option for controlling CBB in smallholder common bean production systems. This study was carried out to determine the inheritance pattern of CBB resistance in leaf and pod of four new resistance sources. The four resistant and four susceptible...
Molecular diagnostics of groundnut rosette disease agents in Uganda: Implications on epidemiology and management of groundnut rosette disease
May 2017
The objective of this study was to use molecular diagnostic tools to detect the agents of groundnut rosette disease (GRD) to guide in varietal development and disease management. Samples were collected from both GRD infected and healthy plants and sites geo-referenced. RNA extraction, cDNA synthesis, polymerase chain reaction (PCR) amplification, electrophoresis, staining and visualization were performed according to...
Improvement of physic nut (Jatropha curcas L.) by intraspecific hybridization between ecotypes of Africa and Americana
May 2017
Jatropha curcas is a plant with several attributes, multiples uses and considerable potentials. To mitigate the effects of climatic change, it is necessary to alleviate fossil power energy and increase biofuel energy. Plant-based fuels are among the best renewable sources, and their use can lead to a better balance of CO2 and other greenhouse gases responsible for global warming. The aim of this work was to study the...
Genotype × environment interactions and oil content stability analysis of peanut (Arachis hypogaea L.) in Northern Cameroon
April 2017
High oil content of peanut is a crucial trait for the processing industry, especially in developing countries where most peanuts are for a major source of cooking oil. Twelve peanut (Arachis hypogaea L.) varieties were evaluated at three northern Cameroon locations for two consecutive seasons in order to estimate variability and stability of performance for seed oil content. A randomized complete block design replicated...
Inheritance of resistance to brown spot disease in upland rice in Uganda
April 2017
Brown spot disease caused by Bipolaris oryzae [Breda de Haan (Shoem.)] is one of the most important diseases affecting rice (Oryza sativa L.) worldwide. Host plant resistance is considered an effective, cheap and environment friendly means of managing this disease. Nine rice genotypes with varying resistance levels were crossed in a full diallel mating design including reciprocals and parents. Parents, reciprocals and...
Genotypic evaluation of sugarcane (Saccharum spp. Hybrids) clones for sucrose content in western Kenya
March 2017
Sugarcane variety development programmes primarily envisage breeding of varieties with high cane yields and high sugar content in specific environmental conditions. Key components associated with sugar yields are tonnes of cane per hectare and sucrose content. A study was undertaken to evaluate 22 introduced sugarcane genotypes with three checks (KEN 83-737, EAK73-335 and D8484) for sucrose content in western Kenya. The...
Estimates of combining ability and heritability in cowpea genotypes under drought stress and non-stress conditions in Uganda
February 2017
Cowpea is an important source of food and income for small scale farmers in Uganda. Production is, however, affected by both biotic and abiotic stresses. Drought stress has recently emerged as a serious concern due to the effects of climate change. This study was therefore undertaken to estimate the general and specific combining ability effects of parents and crosses as well as estimate the heritability of delayed leaf...
Induction of flowering in cassava through grafting
February 2017
Flowering in cassava is related to branching. Erect plant architecture is usually preferred by farmers but results in late and scarce flowering, which slows down breeding and genetic studies. The objective of this study was to induce earlier and more abundant flowering, which have become key research needs for cassava. Six non- or late-flowering genotypes were selected for grafting on a profuse, early flowering...
Agro-morphological variability of Zea mays (L.) accessions collected in Southern Benin
January 2017
A better approach to assess plant genetic diversity is the agro-morphological characterization. The main objective of this study was to investigate the morphological variability of 87 maize (Zea mays L.) accessions collected in different agro-ecological zones of southern Benin. Thus, 16 agro-morphological characters (seven quantitative and nine qualitative) were selected from the maize descriptors. The experimental...
Application of marker-assisted backcrossing to improve cowpea (Vignaunguiculata L. Walp) for drought tolerance
December 2016
Molecular-assisted backcrossing (MABC) was used to introgress drought tolerance, Striga and root-knot nematode resistance QTLs into a farmer-preferred widely grown cowpea landrace adapted for intercropping in Burkina Faso. Two backcross populations were developed using two drought tolerant donor lines IT93K-503-1 (nematode resistant) and IT97K-499-35 (Striga resistant) and the drought sensitive landrace Moussa Local as...
A method of estimating broad-sense heritability for quantitative traits in the type 2 modified augmented design
November 2016
Heritability is a basic genetic parameter for quantitative traits that may determine their selection generation and intensity as well as predict their selection response and efficiency in plant breeding. Estimation of heritability varies based on experimental design. The type 2 modified augmented design (MAD2) as an unbalanced experimental design, has been proposed for evaluating numerous unreplicated test genotypes...
Combining ability and gene action in sesame (Sesamum indicum L) elite genotypes by diallel mating design
November 2016
An 8 x 8 diallel cross mating design with the parents and F1s was used to estimate gene action and combining ability for yield and yield characters in sesame (Sesamum indicum L.). The experiment was conducted at the National Semi-Arid Resources Research Institute (NaSARRI), Serere, Uganda during the second season of 2013. The traits involved: days to 50% flowering, days to maturity, height to first branch, height to...
Analysis of genotype x environment interaction and seed yield stability of sesame in Northern Ethiopia
November 2016
The experiment was conducted in Northern Ethiopia from 2011-2013 under rain fed conditions in a total of seven environments vis. E1, E2, E3, E4, E5, E6 and E7. The objective of the study was to evaluate the adaptability and stability of sesame genotypes across environments. 13 sesame genotypes were evaluated and the experiment was laid out in a Randomized Complete Block Design with three replications. The average...
Radio-sensitivity of cowpea to ultra-violet radiation by pollen treatment
November 2016
The technique of pollen irradiation for mutation induction technique has been successfully demonstrated in many crop species. Therefore, the mutagenic effects of UV irradiated pollen on cowpea accessions were investigated. Pollen grains of eight cowpea accessions were irradiated with 30,000µWs/cm2 UV for 60, 120, 180, 240, 300 and 360 minutes. Emasculated flowers of each accession were self-pollinated with...
Effect of seed source and seed age on yield and yield related traits of malt barley (Hordium vulgare L.) varieties at Central Arsi Highlands Ethiopia
October 2016
The major constraints in fulfilling the growing demand of malt barley in Ethiopia are limited as a result of the selection of a favourable production environment and long-time seed storage for market advantages among others are few to mention. Besides, few research findings are available on evaluation of the potential differences across sites and crop management practices to meet malting and brewery industry quality...
Agro-morphological characterization of Fonio millet accessions (Digitaria exilis Stapf.) collected from Boukoumbé, Northwest of Benin
October 2016
Fonio is a cereal food of great socio-economic and cultural importance in south Sahara African Countries. Unfortunately, it is practically absent from National Agricultural Research Programs. To characterize the agro-morphological diversity of fonio ecotypes grown in Benin, twenty accessions collected from Boukoumbé were evaluated in a randomized complete block design (RCBD) with three replicates in Parakou....
Tomato (Lycopersicon esculentum Mill.) varieties evaluation in Borana zone, Yabello district, southern Ethiopia
October 2016
Tomato is one of the most important vegetable in Ethiopia as well as in the world in irrigated regions. It can be produced in a wide range of climatic conditions and many types of soils. Borana zone has potential to produce the crop, but not well done due to technical (production technology) and socio-economic problems. Among technical problem unavailability of seeds of adapted and improved tomato varieties is the most...
Pathogenic and genetic diversity in Puccinia hordei Otth in Australasia
October 2016
Two PCR-fingerprinting primers, (GACA)4 and M13, were tested across 22 pathotypes of Puccinia hordei Otth collected from Australasia over a 30 year period, to assess their usefulness in revealing genetic variability in this pathogen. Both primers revealed polymorphisms among the pathotypes, with (GACA)4 generating a higher level of polymorphism. Molecular analyses revealed evidence of clonality among the P. hordei...
Allelopathic activity of extracts of Citharexylum spinosum L. from Tunisia
October 2016
Allelopathic potential of Citharexylum spinosum L. (Verbenaceae) an exotic tree introduced in Tunisia many years ago was evaluated. Organic extracts using hexane, ethyl acetate and methanol solvents together with aqueous extracts at different concentrations were prepared from different parts of the plant (roots, stems, leaves and flowers). Yields in the 12 organic extracts together with their phenol contents were...
Evaluation of large seeded faba bean genotypes for agronomic performance in vertisol areas of Southern Tigray, Ethiopia
October 2016
Thirty-two faba bean genotypes were evaluated for their yield and yield components in verstisol areas of Hashenge and Aiba in 2015. Alpha lattice design with two replications was used for the experiment. The Analysis of Variance showed highly significant differences (P<0.01) for thousand seed weight over locations. Based on this, genotype EH 06007-2 scored highest 1000 seed weight (1111 g) followed by EH 06088-6...
Organic and mineral fertilizer effects on growth and yield of cocoyam in a tropical Ultisol in South Eastern Nigeria
October 2016
The performance of cocoyam (Colocasia esculenta L. Schott) to varying levels of cow dung and potassium fertilizer was investigated in 2012 and 2013 cropping seasons under field conditions at National Horticultural Research Institute (NIHORT), Imo State, Nigeria. The experiment was a 4 × 2 factorial arrangement in a randomized complete block design with three replications. The treatments were four levels of cow...
Heritability analysis to screen elite sugarcane (Saccharum spp.) soma clones under field condition
September 2016
Three elite sugarcane varieties were used in this experiment to check the heritability parameters which consist of range, environmental variance, genetic variance, genetic advance and broad sense heritability. Four hundred and five soma clones were observed for phenotypic characters including number of tillers (plant-1), cane height (cm), number of internode (plant-1) and width of internode (cm). Variability range for...
Stability, agronomic performance and genetic variability of 10 cassava genotypes in Ghana
September 2016
Genetic enhancement of cassava aimed at increasing productivity through the provision of broad-based which improved germplasm and is also a major goal for cassava breeders. 10 genotypes (4 landraces and 6 developed lines) were evaluated at Fumesua, Ejura and Pokuase in 2 growing seasons in a randomized complete block design in 3 replicates to determine variability among genotypes for fresh root yield (FRY), root number...
Genetic variation for corm yield and other traits in Ethiopian enset (Ensete ventricosum (Welw.) Cheesman)
September 2016
Enset (Ensete ventricosum (Welw.) Cheesman) is a multipurpose crop used for food, fuel, housing materials, fencing and livestock feed. The major food types obtained from enset are kocho, bulla and amicho. Kocho is fermented starch obtained from decorticated (scraped) leaf sheaths and grated corms. Bulla is obtained by squeezing out the liquid containing starch from scraped leaf sheathes and grated corm and...
Inbreeding enhances field resistance to cassava brown streak viruses
August 2016
Cassava brown streak disease (CBSD) is currently the major disease affecting cassava production in Eastern and Southern Africa. Breeding for resistance has been hampered by a lack of sources of resistance and the complexity of CBSD. This study was initiated to assess the possibility of exploiting inbreeding, as a strategy for generating new sources of resistance to CBSD. This was based on the premise that inbreeding...
Comparing pollination control bag types for sorghum seed harvest
August 2016
Efficacy of pollination bags made of new nonwoven fabrics was compared with the traditional paper bags in sorghum during 2015 using three cultivars comprising BR007B (red seeded), SC283 (white seeded) and 1167048 hybrid with tannin (brown seeded). The five pollination bag treatments were: no bagging, traditional paper bag, paper bag plus plastic screen bag for extra bird protection, duraweb® SG2 polypropylene bag...
Characterization of leaf rust resistance in international barley nurseries
August 2016
Barley nurseries comprising 820 lines with 479 unique pedigrees sourced from the International Centre for Agricultural Research in the Dry Areas (ICARDA) were screened for seedling and adult plant resistance (APR) against Australian isolates of barley leaf rust pathogen Puccinia hordei Otth. Ninety three percent of the lines were postulated to carry the seedling leaf rust resistance gene Rph3 based on their...
Correlation and path co-efficient analysis for grain quality traits in F1 generation of rice (Oryza sativa L.)
July 2016
A study on correlation and path co-efficient analysis was conducted on eleven F1 generation derived from crosses between aromatic and non-aromatic parental landraces genotypes. The results showed that high standard deviation was observed on head rice recovery (16.12) followed by gel consistence (13.81) and milling recovery (10.74). The results also showed that correlation between brown rice length and paddy grain width...
Assessment of advanced Kenyan selected wheat lines for resistance to the prevailing stem rust races (Puccinia graminis f.sp.tritici) in Kenya
July 2016
Stem rust (Puccinia graminis f.sp.tritici) of wheat (Triticum aestivum) has caused wheat yield losses in Kenya for years and the trend shows the situation has worsened. The objective of the research was to identify elite genotypes for adult plant and seedling stage resistance. Adult plant resistance study was done under natural conditions in three locations. Scoring was done following the modified Cobbs scale. Seedling...
Genetic control of resistance to rosette virus disease in groundnut (Arachis hypogaea L.)
June 2016
Groundnut rosette disease is one of the most damaging diseases militating against groundnut production in sub-Saharan Africa. The disease cause up to 100% yield loss whenever epidemic occurs. The most effective, economic and environmental friendly method to control the disease is through genetic resistance. Knowledge on inheritance of resistance to the rosette disease is required to accelerate breeding of resistant...
Selection of cooking banana genotypes for yield and black Sigatoka resistance in different locations in Uganda
May 2016
It is imperative to systematically evaluate new banana genotypes in different locations before national release. This enables selection and recommendation of superior genotypes as new varieties for a wider range of environments. The objective of the present study was to select banana genotypes with stable and high performance for bunch yield and leaf black Sigatoka resistance. Eleven cooking banana genotypes developed...
Efficiency of selection indices in screening bread wheat lines combining drought tolerance and high yield potential
May 2016
Drought is the most severe production constraint for wheat worldwide. Evaluating performance of bread wheat lines and predicting drought tolerance is an essential part of the breeding process. The objective of this study is to investigate the efficiency of several indices in identifying wheat genotypes combining drought tolerance and high yield potential. Twenty-four indices, which were most frequently used in plant...
Revisiting the ignored Ethiopian durum wheat (Triticum turgidum var. durum) landraces for genetic diversity exploitation in future wheat breeding programs
April 2016
The majority of Ethiopian durum wheat are farmers’ varieties. Durum wheat varieties under production in Ethiopia are less productive due to the effect of climate change and marginalism of agricultural inputs. Recognizant to these, revisiting farmers varieties, ex-situ conserved, could be among the best options to adapt these changes. This study has thoroughly characterized a set of 49 durum wheat varieties to...
Enhancement of lodging resistance and productivity of rice using growth regulators at different nitrogen levels
March 2016
Lodging of rice in Egypt reduces production and may be related to the agronomic practices. A 2-years field experiment was conducted at the Experimental Farm of Rice Research and Training Center, Kafr El-Sheikh, Egypt, during two growing summer seasons of 2013 and 2014 to study the effect of growth regulators application at different nitrogen levels on lodging resistance and productivity of Sakha102 rice cultivar....
Evaluation of tropical maize inbred lines for resistance to two stem borer species, Busseola fusca and Chilo partellus
February 2016
Stem borers, Busseola fusca (Fuller) Noctuidae, Lepidoptera and Chilo partellus (Swinhoe) Pyralidae, Lepidoptera, are serious insect pests of maize. However, genotypes showing exclusive resistance to each of these borers and with resistance to both species have not been identified in Kenya. The objective of this study was to evaluate tropical maize inbred lines for resistance to the two species. 112 maize inbred lines...
Genotype × environment interaction on sugar and biomass production in sweet sorghum (Sorghum bicolor (L). Moench) in western Kenya
February 2016
Genotype x environment interaction was determined from field experiments conducted to evaluate sweet sorghum genotypes in Western Kenya during the 2011, 2012 and 2013 rainy season from April to July at Alupe, Kibos, Homa Bay and Spectre International farm. The materials used in the study consisted of sixteen sweet sorghum genotypes and two sorghum genotypes sourced from ICRISAT and KARI. The treatments were laid out in...
Population genetic structure and diversity analysis of South Indian banana cultivars
January 2016
Banana and plantain (Genus: Musa; Family: Musaceae) are giant perennial rhizomatous herbs native to South East Asia and Western Pacific. Present study analyzed the genetic population structure and diversity of South Indian Musa cultivars belonging to different genome groups using random amplified polymorphic (RAPD) markers. The total genetic diversity for all groups (Ht) was 0.22 and within groups (Hs) was 0.07...
Genetic diversity of Dacryodes edulis provenances used in controlled breeding trials
December 2015
Genetic diversity characterization among Dacryodes edulis accessions is important in developing genetically diverse and superior cultivars. This study assessed the genetic diversity of three D. edulis provenances used in controlled breeding trials at ICRAF-Cameroon based on SSR marker technique. Genomic DNA isolated from individual D. edulis samples were primed with six SSR primers (CB09, LD06, CG11, LB12 CE09 and...
Combining ability for stem borer resistance and heterotic orientation of maize inbred lines using CIMMYT single cross testers under Chilo partellus infestation
November 2015
The spotted stem borer, Chilo partellus, Swinhoe (Lepidoptera, Crambidae) is one of the most destructive insect pests of maize in tropical environments. However, the combining ability and heterotic orientation of the germplasm for grain yield and borer resistance is limited. The objective of this study was to determine combining ability and heterotic orientation of new maize inbred lines under C. partellus infestation....
A study on banana miRNA and its application in resistance to Fusarium wilt
October 2015
MicroRNAs refer to a class of short noncoding RNAs (containing about 22 to 24 nucleotides) widely found in eukaryotes, which function in post-transcriptional regulation of target gene expression via base pairing with specified sequences within target mRNAs to cleave target mRNAs or to repress their translation. This paper mainly introduces the research progress of banana miRNA in biological study of resistance to...
Appraisal of soybean RIL population derived from a cross between ‘Spencer’ by ‘LS97-1610’
September 2015
The selection of genotypes based on phenotypic data requires evaluation through different environments in order to accurately measure the genotype x environment (GxE) interaction effect. The purpose of this study was to assess 94 F5:8 recombinant inbred lines (RIL) in terms of their yield performance and other agronomic traits (that is, height, maturity, and lodging); and compare the results to the parental lines (that...
Heterosis and combining ability effect of protein content on rice (Oryza sativa L.) genotypes
August 2015
The study comprised of a set of 56 F1s and F2s which were developed at the Teaching and Research farm of the Federal University of Technology, Owerri, Nigeria, during the early season of 2007. The parental lines consisting of eight genotypes of rice were grouped into low, medium and high protein parents and crosses were made in all possible combinations. The laboratory analysis for the protein content determination was...
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