PubAg

Main content area

You searched for: Author "Derera, John" Remove constraint Author: "Derera, John"
Start Over

Search

39  Search Results

1 - 39 of 39
Number of results to display per page

Search Results

1. Genetic variability of faba bean genotypes for chocolate spot (Botrytis fabae) resistance and yield

Author:
Derera, John,   et al.   ; Beyene, Asnakech T.; Sibiya, Julia;     Show all 3 Authors
Source:
Euphytica 2018 v.214 no.8 pp. 132
ISSN:
0014-2336
Subject:
Botrytis fabae; Vicia faba; agronomic traits; chocolate spot disease; cultivars; disease control; disease course; disease outbreaks; disease resistance; faba beans; fungi; genetic variation; genotype; landraces; leaves; pathogens; phenotypic selection; small-scale farming; soil fertility; Ethiopia
Abstract:
... Faba bean (Vicia faba L.) has high utility as a food and soil fertility improving crop. One of the major fungal pathogens of faba bean is Botrytis fabae, the causative agent of chocolate spot. The disease affects significantly the leaf, stem, pod and seed of faba bean compromise its productivity in the smallholder farming sector. Nonetheless, there are limited resistant/tolerant faba bean varietie ...
DOI:
10.1007/s10681-018-2210-7

2. Why SR52 is such a great maize hybrid? II. Heritability, correlation and path-coefficient analyses

Author:
Derera, John,   et al.   ; Musimwa, Tatenda R.;     Show all 2 Author
Source:
Euphytica 2017 v.213 no.3 pp. 62
ISSN:
0014-2336
Subject:
Zea mays; backcrossing; corn; gene pool; grain yield; heritability; heterosis; hybrids; inbred lines; models; path analysis; phenotypic variation; plant breeding; seeds
Abstract:
... Although exceptional heterosis for yield in the world’s first commercial single cross maize (Zea mays L.) hybrid SR52 has been confirmed, the role of secondary traits hasn’t been established. Objectives of this study were to establish relationship between grain yield and secondary traits, while assessing heritability and genotypic variation in SR52’s segregating populations. Knowledge on associati ...
DOI:
10.1007/s10681-017-1851-2

3. Molecular characterisation of maize introgressed inbred lines bred in different environments

Author:
Derera, John,   et al.   ; Musundire, Lennin; Dari, Shorai; Tongoona, Pangirayi; Cairns, Jill E.;     Show all 5 Authors
Source:
Euphytica 2019 v.215 no.3 pp. 46
ISSN:
0014-2336
Subject:
Zea mays; alleles; allelic variation; breeding programs; corn; genetic distance; genetic markers; genotype; germplasm; heterosis; hybrids; inbred lines; introgression; loci; microsatellite repeats; pedigree; plant breeding; South Africa; Zimbabwe
Abstract:
... Establishing detailed information on genetic diversity and relationships among maize (Zea mays L.) inbred lines in a breeding programme help ensure effective utilization of germplasm. Introgression of temperate maize germplasm into 12 tropical elite maize inbred lines using a common donor inbred line and different selection environments might disrupt the heterotic grouping system. Therefore, the o ...
DOI:
10.1007/s10681-019-2367-8

4. Development, evaluation and genetic analysis of sulfosulfuron herbicide resistance in sorghum

Author:
Derera, John,   et al.   ; Ndung’u, DavidK.; Tongoona, Pangirayi; Ransom, Joel;     Show all 4 Authors
Source:
Journal of crop science and biotechnology 2017 v.20 no.4 pp. 315-325
ISSN:
1975-9479
Subject:
Striga; coatings; crossing; ethyl methanesulfonate; genetic analysis; herbicide resistance; herbicides; inheritance (genetics); lethal dose 50; mutants; mutation; progeny; seed coat; seed treatment; spraying; Kenya
Abstract:
... Herbicide tolerant varieties in combination with herbicide seed treatments can be used to manage Striga. However, there are no herbicide resistant sorghum varieties in Kenya. The objectives of this study, therefore, were to develop sulfosulfuron resistance in sorghum, to determine the level of resistance in resultant herbicide tolerant mutants, and to determine the genetic inheritance of herbicide ...
DOI:
10.1007/s12892-017-0109-0

5. Genotype-by-environment interaction and yield stability of quality protein maize hybrids developed from tropical-highland adapted inbred lines

Author:
Derera, John,   et al.   ; Abakemal, Demissew; Shimelis, Hussein;     Show all 3 Authors
Source:
Euphytica 2016 v.209 no.3 pp. 757-769
ISSN:
0014-2336
Subject:
Zea mays; agroecology; corn; cultivars; genotype; genotype-environment interaction; grain yield; hybrids; inbred lines; plant breeding; Ethiopia
Abstract:
... Maize (Zea mays L.) yields are significantly lower in the tropical-highlands than other environments predominantly due to the lack of well-adapted and improved cultivars and due to genotype by environment (G × E) interaction. The objectives of this study were to determine G × E interaction and yield stability of quality protein maize (QPM) single-cross hybrids recently developed from tropical-high ...
DOI:
10.1007/s10681-016-1673-7

6. Why SR52 is such a great maize hybrid? I. Heterosis and generation mean analysis

Author:
Derera, John,   et al.   ; Musimwa, Tatenda R.;     Show all 2 Author
Source:
Euphytica 2015 v.205 no.1 pp. 121-135
ISSN:
0014-2336
Subject:
Zea mays; additive gene effects; backcrossing; corn; epistasis; genes; grain yield; heterosis; hybrids; models; parents; plant breeding; yield components; South Africa; Zimbabwe
Abstract:
... SR52 is the first single cross maize hybrid to be commercialised in the world and forms the basis of maize breeding in Zimbabwe and Eastern and Southern Africa region. Although SR52 is such an exceptional hybrid, the genetic basis of its outstanding yield and heterosis has never been explained. Therefore genetic components of yield and associated traits in SR52 were studied using a generation mean ...
DOI:
10.1007/s10681-015-1410-7

7. Response of maize population “Longe5” to two cycles of modified S1 recurrent selection for resistance to maize weevil

Author:
Derera, John,   et al.   ; Kasozi, Lwanga Charles; Tongoona, Pangirayi;     Show all 3 Authors
Source:
Euphytica 2015 v.204 no.3 pp. 587-598
ISSN:
0014-2336
Subject:
Sitophilus zeamais; corn; crops; foliar diseases; genotype; grain yield; grey leaf spot disease; leaf blight; plant breeding; recurrent selection; rust diseases; self-pollination; storage pests; subtropics; weight loss; Uganda
Abstract:
... The maize weevil (Sitophilus zeamais Mostch.) is one of the most damaging storage pests causing significant reductions in grain weight and quality in tropical and subtropical regions. The current study determined the effectiveness of two cycles of modified S₁ recurrent selection towards the improvement of weevil resistance in the maize variety “Longe5”. Grain yield and resistance to Turcicum leaf ...
DOI:
10.1007/s10681-014-1341-8

8. Genetic Components of Grain Yield Stability in Maize Diallel Crosses

Author:
Derera, John,   et al.   ; Gichuru, Lilian; Tongoona, Pangirayi; Njoroge, Kiarie; Murenga, Mwimali;     Show all 5 Authors
Source:
Journal of crop improvement 2016 v.30 no.2 pp. 217-243
ISSN:
1542-7536
Subject:
Zea mays; agronomic traits; corn; diallel analysis; general combining ability; genotype; genotype-environment interaction; grain yield; hybrids; parents; variance; Kenya
Abstract:
... In sub-Saharan Africa, maize (Zea mays L.) is produced in very diverse environments, which often results in complex genotype-by-environment (G × E) interactions. The aim of the study was to identify genotypes with broad and specific adaptation and high-performance environments that offer the best discrimination for selection and assess parents’ contribution to hybrid stability. Sixty-six F ₁ maize ...
DOI:
10.1080/15427528.2016.1141342

9. Combining ability for stem borer resistance and heterotic orientation of maize inbred lines using CIMMYT single cross testers under Busseola fusca infestation

Author:
Derera, John,   et al.   ; Mwimali, Murenga; Tongoona, Pangirayi; Mugo, Stephen; Gichuru, Lilian;     Show all 5 Authors
Source:
Euphytica 2016 v.208 no.2 pp. 323-335
ISSN:
0014-2336
Subject:
Busseola fusca; additive gene effects; corn; general combining ability; genotype; genotype-environment interaction; grain yield; heterosis; hybrids; inbred lines; insect pests; plant breeding; specific combining ability; testcrosses; Kenya
Abstract:
... The African stem borer, Busseola fusca Fuller, is one of the most devastating insect pests of maize in tropical environments. Understanding of combining ability and heterosis may be useful for designing insect resistant hybrids. However, among the adapted maize inbred lines used in this study, the combining ability and heterotic orientation for grain yield and borer resistance is not known. The ob ...
DOI:
10.1007/s10681-015-1602-1

10. Heterosis and combining ability of elite maize inbred lines under northern corn leaf blight disease prone environments of the mid-altitude tropics

Author:
Derera, John,   et al.   ; Abera, Wende; Hussein, Shimelis; Worku, Mosisa; Laing, Mark;     Show all 5 Authors
Source:
Euphytica 2016 v.208 no.2 pp. 391-400
ISSN:
0014-2336
Subject:
Zea mays; corn; cultivars; farmers; females; general combining ability; grain yield; heterosis; hybrids; inbred lines; leaf blight; males; parents; plant breeding; specific combining ability; tropics; Ethiopia
Abstract:
... Yields of maize (Zea mays L.) are remarkably low in sub-Saharan Africa and yet farmers have limited access to improved varieties. The objective of this study was to determine combining ability and heterosis of 18 elite maize inbred lines in environments prone to northern corn leaf blight (NCLB) disease in the mid-altitude tropics. Nine elite inbred lines were crossed as females with nine male line ...
DOI:
10.1007/s10681-015-1619-5

11. Gene action determining grain yield and chocolate spot (Botrytis fabae) resistance in faba bean

Author:
Derera, John,   et al.   ; Beyene, Asnakech Tekalign; Sibiya, Julia; Fikre, Asnake;     Show all 4 Authors
Source:
Euphytica 2016 v.207 no.2 pp. 293-304
ISSN:
0014-2336
Subject:
Botrytis fabae; Vicia faba; additive gene effects; chocolate spot disease; diallel analysis; disease resistance; faba beans; general combining ability; genes; genotype; grain yield; hybrids; maternal effect; pathogens; plant breeding; specific combining ability; Ethiopia
Abstract:
... Production of faba bean (Vicia faba L.) is hampered by chocolate spot disease caused by Botrytis fabae. Studies of the genetics of resistance is vital to devise a viable strategy for faba bean breeding. The present study was carried out with the objective to determine the mode of inheritance and maternal effect for chocolate spot resistance and yield. A 10 × 10 full diallel mating design was used ...
DOI:
10.1007/s10681-015-1536-7

12. Genetic analysis of mechanisms associated with inheritance of resistance to sheath rot of rice

Author:
Derera, John,   et al.   ; Mvuyekure, Simon Martin; Sibiya, Julia; Nzungize, John; Nkima, Germain;     Show all 5 Authors
Source:
Plant breeding 2017 v.136 no.4 pp. 509-515
ISSN:
0179-9541
Subject:
additive effect; additive gene effects; disease resistance; dominant genes; genetic analysis; genetic resistance; genotype; heritability; horizontal resistance; hybrids; inheritance (genetics); introgression; parents; phenotype; recessive genes; recurrent selection; rice; specific combining ability
Abstract:
... Understanding genetic mechanisms controlling inheritance of disease resistance traits is essential in breeding investigations targeting development of resistant genotypes. Using North Carolina design II, 32 F₁ hybrids were generated by crossing eight susceptible to four resistant parents and submitted for field evaluation. The analysis of general and specific combining ability (GCA and SCA) indica ...
DOI:
10.1111/pbr.12492

13. Response to S1 recurrent selection for resistance to two stem borers, Busseola fusca and Chilo partellus, in two tropical maize populations

Author:
Derera, John,   et al.   ; Mwimali, Murenga; Mugo, S.; Tongoona, P.;     Show all 4 Authors
Source:
Euphytica 2015 v.206 no.3 pp. 711-723
ISSN:
0014-2336
Subject:
Busseola fusca; Chilo partellus; adverse effects; alleles; boring insects; corn; genetic improvement; grain yield; heritability; leaves; pest resistance; progeny; recurrent selection; Kenya
Abstract:
... Stem borers, Busseola fusca and Chilo partellus, are among the key devastating lepidopteran insect pests of maize causing grain yield losses. Recurrent selection studies for stem borer resistance in maize are limited. However, maize populations carrying resistance genes to these stem borers have not been exploited fully in breeding programmes. The objective of the study was to separately improve r ...
DOI:
10.1007/s10681-015-1496-y

14. Genetic purity and patterns of relationships among tropical highland adapted quality protein and normal maize inbred lines using microsatellite markers

Author:
Derera, John,   et al.   ; Abakemal, Demissew; Hussein, Shimelis; Semagn, Kassa;     Show all 4 Authors
Source:
Euphytica 2015 v.204 no.1 pp. 49-61
ISSN:
0014-2336
Subject:
Zea mays; cluster analysis; corn; genes; genetic distance; genetic markers; genetic variation; heterozygosity; humans; inbred lines; microsatellite repeats; nutritive value; pedigree; plant breeding; population structure; selfing; variance
Abstract:
... Conversion of normal maize (Zea mays L.) into quality protein maize (QPM) significantly improves its nutritional value for humans and animals. Highland adapted normal maize inbred lines were backcrossed with selected QPM donor lines to incorporate the opaque-2 gene. The objectives of this study were to verify the genetic purity, determine the effect of conversion of normal maize lines to QPM and u ...
DOI:
10.1007/s10681-014-1332-9

15. Genotypic Response in Rice During the Vegetative Phase under Water Stress and Non-stress Conditions

Author:
Derera, John,   et al.   ; Efisue, Andrew A.;     Show all 2 Author
Source:
Journal of crop improvement 2012 v.26 no.6 pp. 816-834
ISSN:
1542-7536
Subject:
Oryza glaberrima; Oryza sativa; breeding; crop production; drought tolerance; environmental factors; genetic stability; genotype; genotype-environment interaction; irrigation rates; rice; sowing; sprinkler irrigation; stress tolerance; vegetative growth; water stress; Mali
Abstract:
... Drought stress during the vegetative stage can cause irreversible damage to rice (Oryza sativa L.) plants, resulting in inadequate grain production. Morpho-physiological traits have been used as indirect measures of drought-stress tolerance in rice, but these traits are genotype and environment dependent. This study was therefore conducted to determine which morpho-physiological traits were associ ...
DOI:
10.1080/15427528.2012.720359

16. Effects of amaranth addition on the pro‐vitamin A content, and physical and antioxidant properties of extruded pro‐vitamin A‐biofortified maize snacks

Author:
Derera, John,   et al.   ; Beswa, Daniso; Dlamini, Nomusa R; Amonsou, Eric O; Siwela, Muthulisi;     Show all 5 Authors
Source:
Journal of the science of food and agriculture 2016 v.96 no.1 pp. 287-294
ISSN:
0022-5142
Subject:
antioxidant activity; corn; foods; hardness; health promotion; leaves; snacks; vegetables; vitamin A; vitamin A deficiency; Southern Africa
Abstract:
... BACKGROUND: Pro‐vitamin A‐biofortified maize snacks with added leafy vegetable may have a potential as nutritious and health‐promoting products, especially in addressing vitamin A deficiency, which is prevalent in developing regions. The objective of the study was to determine the effects of adding amaranth leaf powder on the physical, antioxidant properties and pro‐vitamin A content of extruded p ...
DOI:
10.1002/jsfa.7092

17. Combining ability and GGE biplot analyses for resistance to northern leaf blight in tropical and subtropical elite maize inbred lines

Author:
Derera, John,   et al.   ; Sibiya, Julia; Tongoona, Pangirayi;     Show all 3 Authors
Source:
Euphytica 2013 v.191 no.2 pp. 245-257
ISSN:
0014-2336
Subject:
additive effect; corn; diallel analysis; disease resistance; disease severity; genes; genotype; grain yield; hybrids; inbred lines; inheritance (genetics); leaf blight; linear models; screening; specific combining ability; South Africa; Zambia
Abstract:
... The incidence and severity of northern leaf blight (NLB) disease has increased in Southern Africa in the past years with previously resistant cultivars being affected; implying more resistant sources have to be identified and inheritance of NLB resistance investigated. Therefore, 45 F₁ hybrids generated in a half diallel mating of ten elite maize inbred lines were evaluated in six environments for ...
DOI:
10.1007/s10681-012-0806-x

18. Resistance of maize to the maize weevil: III. Grain weight loss assessment and implications for breeding

Author:
Derera, John,   et al.   ; Pixley, Kevin V.; Giga, Denash P.; Makanda, Itai;     Show all 4 Authors
Source:
Journal of stored products research 2014 v.59 pp. 24-35
ISSN:
0022-474X
Subject:
Sitophilus zeamais; Zea mays; ambient temperature; corn; data collection; farmers; females; food security; genes; genotype; grain yield; humidity; hybrids; males; pest resistance; pests; recurrent selection; stored grain; subtropics; weight loss; Zimbabwe
Abstract:
... The maize weevil (Sitophilus zeamais) is a significant pest of stored maize grain in tropical and subtropical regions worldwide. As a further step towards finding maize genotypes with acceptable levels of resistance to the maize weevil, 53 experimental maize hybrids that were generated in a North Carolina design II mating scheme, were evaluated for grain weight loss due to maize weevil damage unde ...
DOI:
10.1016/j.jspr.2014.04.004

19. Genetic inheritance of resistance to cowpea aphid-borne mosaic virus in cowpea

Author:
Derera, John,   et al.   ; Orawu, Martin; Melis, Rob; Laing, Mark;     Show all 4 Authors
Source:
Euphytica 2013 v.189 no.2 pp. 191-201
ISSN:
0014-2336
Subject:
Cowpea aphid-borne mosaic virus; cowpeas; cultivars; general combining ability; hybridization; inheritance (genetics); landraces; parents; progeny; recessive genes; recurrent selection; specific combining ability; viruses; Uganda
Abstract:
... Cowpea aphid-borne mosaic virus (CABMV) is a major virus disease in Uganda that causes substantial loss of the cowpea crop especially in growth and yield. The mode of gene action conferring resistance to the virus is not well understood. The objective of the study was to determine the genetic inheritance of resistance in cowpea crosses. Three susceptible (S) cowpea landraces that are commonly grow ...
DOI:
10.1007/s10681-012-0756-3

20. Combining ability analysis across environments for some traits in dry bean (Phaseolus vulgaris L.) under low and high soil phosphorus conditions

Author:
Derera, John,   et al.   ; Kimani, J. M.;     Show all 2 Author
Source:
Euphytica 2009 v.166 no.1 pp. 1-13
ISSN:
0014-2336
Subject:
Phaseolus vulgaris; dry beans; plant breeding; hybrids; agronomic traits; soil fertility; nutrient availability; nutrient deficiencies; general combining ability; specific combining ability; nutrition-genotype interaction; additive gene effects; early development; inheritance (genetics); Kenya
Abstract:
... Dry bean (Phaseolus vulgaris L.) is an important grain legume for small-scale farmers in eastern Africa who nonetheless, grow beans with limited phosphorus (P) fertilizer supply or none at all. Phosphorus rank second, after nitrogen (N), as the most limiting soil nutrient in bean production in East African soils. This study was conducted to determine combining ability for five polygenic traits in ...
DOI:
10.1007/s10681-008-9795-1

21. Heterotic orientation of tropical maize inbred lines towards populations ZM523 and Suwan-1 under downy mildew infestation

Author:
Derera, John,   et al.   ; Fato, Pedro; Tongoona, Pangirayi; Makanda, Itai; Sibiya, Julia;     Show all 5 Authors
Source:
Euphytica 2012 v.187 no.3 pp. 381-392
ISSN:
0014-2336
Subject:
additive gene effects; corn; downy mildew; general combining ability; genes; grain yield; heterosis; inbreeding; lowlands; specific combining ability; synthetic populations
Abstract:
... Development of top cross varieties with downy mildew (DM) resistance is one approach to enhance maize productivity in tropical lowland environments. The objective of this study was to determine heterotic orientation of 18 advanced maize inbred lines towards popular open pollinated synthetic populations ZM523 and Suwan-1 under the prevalence of DM. The 36 top crosses, four hybrid check varieties an ...
DOI:
10.1007/s10681-012-0716-y

22. Genetic analysis and genotype × environment (G × E) for grey leaf spot disease resistance in elite African maize (Zea mays L.) germplasm

Author:
Derera, John,   et al.   ; Sibiya, Julia; Tongoona, Pangirayi; van Rij, Neil;     Show all 4 Authors
Source:
Euphytica 2012 v.185 no.3 pp. 349-362
ISSN:
0014-2336
Subject:
Zea mays; additive gene effects; control methods; corn; disease resistance; disease severity; foliar diseases; general combining ability; genetic techniques and protocols; genotype; germplasm; grain yield; hybrids; inheritance (genetics); leaf spotting; regression analysis; specific combining ability; South Africa
Abstract:
... Maize grey leaf spot (GLS) disease remains an important foliar disease in sub-Saharan Africa accounting for more than 25% yield losses in maize. Information on inheritance of GLS resistance of germplasm adapted to African environments is required in new sources being identified. Therefore, hybrids generated from a 10 × 10 half-diallel mating of tropical advanced maize inbred lines were evaluated i ...
DOI:
10.1007/s10681-011-0466-2

23. Geostatistical Analysis of Quality Protein Maize Outcrossing with Pollen from Adjacent Normal Endosperm Maize Varieties

Author:
Derera, John,   et al.   ; Machida, Lewis; Tongoona, Pangirayi; Mutanga, Onisimo; MacRobert, John;     Show all 5 Authors
Source:
Crop science 2012 v.52 no.3 pp. 1235-1245
ISSN:
0011-183X
Subject:
kriging; Zea mays; alleles; outcrossing; geostatistics; models; corn; endosperm; grain quality; pollen; prediction; crops; Zimbabwe
Abstract:
... Nutritional advantages of quality protein maize (QPM) (Zea mays L.) over normal endosperm maize (NM) were previously demonstrated by several researchers. However, QPM grain quality loss occurs when a QPM crop receives pollen from NM. This is because the opaque-2 gene allele that confers the QPM trait is recessive. The objective was to estimate outcrossing levels and patterns in QPM growing adjacen ...
DOI:
10.2135/cropsci2011.08.0448

24. Gene action and reciprocal effects for ear rot resistance in crosses derived from five tropical maize populations

Author:
Derera, John,   et al.   ; Mukanga, Mweshi; Tongoona, Pangirayi;     Show all 3 Authors
Source:
Euphytica 2010 v.174 no.2 pp. 293-301
ISSN:
0014-2336
Subject:
Zea mays; corn; grain crops; Aspergillus flavus; Gibberella fujikuroi; Stenocarpella maydis; plant pathogenic fungi; ear rot; reciprocal crosses; grain yield; general combining ability; specific combining ability; environmental factors; genetic variation; genotype; genotype-environment interaction; additive gene effects; disease severity; plastid DNA; disease resistance; genetic resistance; Zambia
Abstract:
... Devastating maize grain yield and quality losses are caused by Aspergillus flavus, Fusarium verticillioides and Stenocarpella maydis ear rots especially in tropical countries. Therefore, combining ability of tropical maize populations for ear rot severity and ear rot-related traits was investigated. Ten full-sib progenies, comprising one resistant and one susceptible from each of the five populati ...
DOI:
10.1007/s10681-010-0178-z

25. Combining ability and heterosis of sorghum germplasm for stem sugar traits under off-season conditions in tropical lowland environments

Author:
Derera, John,   et al.   ; Makanda, Itai; Tongoona, Pangirayi;     Show all 3 Authors
Source:
Field crops research 2009 v.114 no.2 pp. 272-279
ISSN:
0378-4290
Subject:
Sorghum bicolor; sweet sorghum; germplasm; plant genetic resources; heterosis; tropics; biofuels; stems; cultivars; plant breeding; specific combining ability; general combining ability; crop management; brix; additive gene effects; plant adaptation; South Africa; Mozambique
Abstract:
... Bioethanol production from sweet sorghum entails expansion and intensive production of the crop, which may include off-season production in the warm tropical lowlands. However, suitable cultivars are currently not available for this environment, especially in southern Africa. Hybrid cultivars were long ago demonstrated to be more productive than pure line varieties. Therefore a study was conducted ...
DOI:
10.1016/j.fcr.2009.08.009

26. Genetic interrelationships among medium to late maturing tropical maize inbred lines using selected SSR markers

Author:
Derera, John,   et al.   ; Wende, Abera; Shimelis, Hussein; Mosisa, Worku; Danson, Jedidah; Laing, Mark D.;     Show all 6 Authors
Source:
Euphytica 2013 v.191 no.2 pp. 269-277
ISSN:
0014-2336
Subject:
alleles; breeding lines; corn; genetic distance; genetic markers; hybrids; inbred lines; inbreeding; microsatellite repeats; pedigree
Abstract:
... Understanding the genetic relationships among breeding lines is fundamental in crop improvement programs. The objectives of this study were to apply selected polymorphic single sequence repeat (SSR) DNA markers and cluster medium to late maturing tropical elite maize inbred lines for effective hybrid breeding. Twenty elite inbred lines were genotyped with 20 SSR markers. The analysis detected a to ...
DOI:
10.1007/s10681-012-0826-6

27. Combining Ability and Reciprocal Cross Effects of Elite Quality Protein Maize Inbred Lines in Subtropical Environments

Author:
Derera, John,   et al.   ; Machida, Lewis; Tongoona, Pangirayi; MacRobert, John;     Show all 4 Authors
Source:
Crop science 2010 v.50 no.5 pp. 1708-1717
ISSN:
1435-0653
Subject:
heterosis; flowering; reciprocal crosses; hybrids; phenotype; phenology; genotype; grain yield; germplasm; Zea mays; corn; genotype-environment interaction; inbred lines; crop quality; general combining ability; tryptophan; environmental factors; agronomic traits; endosperm; protein content; specific combining ability; Zimbabwe
Abstract:
... General combining ability (GCA), specific combining ability (SCA), and reciprocal cross effects information facilitate efficient utilization of inbred lines in a breeding program. A diallel analysis of nine quality protein maize (Zea mays L.) inbred lines was evaluated over seven environments in Zimbabwe. Hybrid × environment interaction was significant for all the traits except for tryptophan con ...
DOI:
10.2135/cropsci2009.09.0538

28. A survey of pre-harvest ear rot diseases of maize and associated mycotoxins in south and central Zambia

Author:
Derera, John,   et al.   ; Mukanga, Mweshi; Tongoona, Pangirayi; Laing, Mark D.;     Show all 4 Authors
Source:
International journal of food microbiology 2010 v.141 no.3 pp. 213-221
ISSN:
0168-1605
Subject:
Zea mays; corn; ear rot; mycotoxins; prevalence; Gibberella fujikuroi; Stenocarpella maydis; Aspergillus flavus; etiology; fungal diseases of plants; enzyme-linked immunosorbent assay; on-farm food safety; Zambia
Abstract:
... Maize ear rots reduce grain yield and quality with implication on food security and health. Some of the pathogenic fungi produce mycotoxins in maize grain posing a health risk to humans and livestock. Unfortunately, the levels of ear rot and mycotoxin infection in grain produced by subsistence farmers in sub-Saharan countries are not known. A survey was thus conducted to determine the prevalence o ...
DOI:
10.1016/j.ijfoodmicro.2010.05.011

29. Awareness of plant-parasitic nematodes, and preferred maize varieties, among smallholder farmers in East and Southern Uganda: implications for assessing nematode resistance breeding needs in African maize

Author:
Derera, John,   et al.   ; Kagoda, Frank; Tongoona, Pangirayi; Coyne, Daniel L.;     Show all 4 Authors
Source:
International journal of pest management 2010 v.56 no.3 pp. 217-222
ISSN:
0967-0874
Subject:
Zea mays; corn; small-scale farming; cultivars; pest resistance; genetic resistance; plant breeding; Pratylenchus zeae; root lesion nematodes; Meloidogyne; root-knot nematodes; plant pests; farmers; farm surveys; knowledge; grain yield; germplasm; incidence; landraces; disease resistance; palatability; storage time; Uganda
DOI:
10.1080/09670870903464382

30. Combining ability and cultivar superiority of sorghum germplasm for grain yield across tropical low- and mid-altitude environments

Author:
Derera, John,   et al.   ; Makanda, Itai; Tongoona, Pangirayi; Sibiya, Julia; Fato, Pedro;     Show all 5 Authors
Source:
Field crops research 2010 v.116 no.1-2 pp. 75-85
ISSN:
0378-4290
Subject:
Sorghum bicolor; grain sorghum; cultivars; general combining ability; specific combining ability; germplasm; plant genetic resources; grain yield; altitude; tropics; hybrids; landraces; heterosis; germplasm screening; cytoplasmic male sterility; agronomic traits; leaves; inflorescences; additive gene effects; Mozambique; South Africa; Zimbabwe
Abstract:
... Sorghum grain production in sub-Saharan Africa is constrained by the fact that farmers' choice of improved varieties is limited. Hybrid cultivars have been shown to be more productive for grain than pure line and landrace varieties hence their development can enhance productivity and food security. This study was, therefore, conducted to determine combining ability of 18 sorghum lines, the level o ...
DOI:
10.1016/j.fcr.2009.11.015

31. A Comparative Analysis of Conventional and Marker-Assisted Selection Methods in Breeding Maize Streak Virus Resistance in Maize

Author:
Derera, John,   et al.   ; Abalo, Grace; Tongoona, Pangirayi; Edema, Richard;     Show all 4 Authors
Source:
Crop science 2009 v.49 no.2 pp. 509-520
ISSN:
1435-0653
Subject:
Zea mays; corn; plant breeding; artificial selection; marker-assisted selection; Maize streak virus; plant viruses; plant diseases and disorders; disease resistance; genetic resistance; selection criteria; inbred lines; backcrossing; selfing; grain yield; disease incidence; disease severity; Uganda
Abstract:
... Reliable information regarding comparative advantage of marker-assisted selection (MAS) over conventional selection (CS) in breeding for maize streak virus (MSV) resistance in maize (Zea mays L.) is scarcely available. A comparative study was, therefore, conducted to determine the efficiency of both methods in breeding for MSV resistance in Uganda. Backcross and selfed-progenies were derived from ...
DOI:
10.2135/cropsci2008.03.0162

32. Genetic analysis of resistance to nematodes in inbred maize (Zea mays L.) and maize hybrids

Author:
Derera, John,   et al.   ; Kagoda, Frank; Tongoona, Pangirayi; Coyne, Daniel L.; Lorenzen, J.;     Show all 5 Authors
Source:
Euphytica 2011 v.182 no.3 pp. 377-393
ISSN:
0014-2336
Subject:
Meloidogyne; Pratylenchus zeae; Zea mays; corn; crossing; cultivars; dominant genes; general combining ability; genetic techniques and protocols; grain yield; hybrids; maternal effect; overdominance; parents; pedigree; roots; specific combining ability; variance; Uganda
Abstract:
... Nematodes cause substantial grain yield loss in susceptible maize (Zea mays L.) cultivars. This study was conducted to estimate general combining ability (GCA), specific combining ability (SCA) and genetic effects associated with nematode resistance in maize. The 30 F 1 hybrids generated from a 6 × 6 diallel and two local checks were evaluated in 2009 at three sites in Uganda. A split plot design ...
DOI:
10.1007/s10681-011-0512-0

33. Genetic analysis of resistance to Fusarium root rot in common bean

Author:
Derera, John,   et al.   ; Mukankusi, Clare; Melis, Rob; Gibson, Paul T.; Buruchara, Robin;     Show all 5 Authors
Source:
Euphytica 2011 v.182 no.1 pp. 11-23
ISSN:
0014-2336
Subject:
Fusarium; additive gene effects; beans; cross resistance; diallel analysis; epistasis; females; general combining ability; genes; heritability; heterosis; loci; maternal effect; parents; polygenic inheritance; progeny; reciprocal crosses; root rot; specific combining ability; Uganda
Abstract:
... Fusarium root rot (FRR) is a major disease of common bean worldwide. Knowledge of the inheritance of resistance to FRR would be important in devising strategies to breed resistant varieties. Therefore, a 12 × 12 full diallel mating scheme with reciprocal crosses was performed to generate 132 F1 progenies, which were then advanced to the F3. The progenies were evaluated for resistance to FRR under ...
DOI:
10.1007/s10681-011-0413-2

34. A New Cheap and Efficient Single-Grain Shatter Tester for Use in Rice Breeding

Author:
Derera, John,   et al.   ; Lamo, Jimmy; Tongoona, Pangirayi; Okori, Patrick; Hendricks, Roelof; Laing, Mark;     Show all 6 Authors
Source:
Crop science 2011 v.51 no.2 pp. 651-655
ISSN:
1435-0653
Subject:
Oryza sativa; breeding; crops; equipment; inflorescences; pedicel; qualitative analysis; rice; Japan; South Africa; Uganda
Abstract:
... Grain shattering, also called grain shedding, is the relative ease with which rice (Oryza sativa L.) seed is dislodged from the pedicel at maturity. Several qualitative methods have been used to assess grain shattering and they tend to underestimate yield loss. Equipments available for quantitative assessment of grain shattering are mostly laboratory based. However, a recently developed prototype ...
DOI:
10.2135/cropsci2010.05.0267

35. Combining ability analysis for Phaeosphaeria leaf spot resistance and grain yield in tropical advanced maize inbred lines

Author:
Derera, John,   et al.   ; Sibiya, Julia; Tongoona, Pangirayi; van Rij, Neil; Makanda, Itai;     Show all 5 Authors
Source:
Field crops research 2011 v.120 no.1 pp. 86-93
ISSN:
0378-4290
Subject:
Phaeosphaeria; corn; cultivars; diallel analysis; disease control; disease resistance; disease severity; flowering; general combining ability; genes; germplasm; grain yield; hybrids; inbred lines; inbreeding; leaf spotting; linear models; parents; regression analysis
Abstract:
... Phaeosphaeria leaf spot (PLS) disease (causal agent Phaeosphaeria maydis (Henn.) Rane, Payak & Renfro) of maize is increasing in importance in sub-Saharan Africa (SSA). However, there is still limited information on the combining ability for disease resistance of the germplasm that are adapted to African environments. Evaluating combining ability effects and their interactions with the environment ...
DOI:
10.1016/j.fcr.2010.09.001

36. Gene action controlling grain yield and secondary traits in southern African maize hybrids under drought and non-drought environments

Author:
Derera, John,   et al.   ; Tongoona, Pangirayi; Vivek, Bindiganavile Sampath; Laing, Mark D.;     Show all 4 Authors
Source:
Euphytica 2008 v.162 no.3 pp. 411-422
ISSN:
0014-2336
Subject:
Zea mays; corn; hybrids; grain yield; drought; water stress; genetic variance; general combining ability; males; females; additive gene effects; specific combining ability; genotype-environment interaction; variety trials; yield components; phenology; Zimbabwe
Abstract:
... Breeding maize hybrids for drought tolerance would significantly reduce yield loss due to drought in southern Africa. Mode of gene action controlling yield and secondary traits was investigated by mating 27 inbred lines, in sets according to a North Carolina design II scheme. The resultant 72 experimental and eight commercial hybrids were evaluated in 8 x 10 α-lattice design with two replications, ...
DOI:
10.1007/s10681-007-9582-4

37. Genetics of morpho-physiological traits in segregating populations of interspecific hybrid rice under stress and non-stress conditions

Author:
Derera, John,   et al.   ; Efisue, Andrew A.; Tongoona, Pangirayi; Ubi, Benjamin E.; Oselebe, Happiness O.;     Show all 5 Authors
Source:
Journal of crop improvement 2009 v.23 no.4 pp. 383-401
ISSN:
1542-7528
Subject:
rice; Oryza sativa; drought tolerance; height; Oryza glaberrima; progeny testing; heritability; hybrids; dry matter accumulation; water stress; gene segregation; interspecific hybridization; leaves; cultivars; chlorophyll; quantitative analysis; irrigated conditions; dominance (genetics); physiological response; inbred lines; general combining ability; agronomic traits; genetic variation; plant morphology; Mali; North Carolina
DOI:
10.1080/15427520902976471

38. Genetic analysis of anthracnose resistance in common bean breeding source germplasm

Author:
Derera, John,   et al.   ; Nkalubo, Stanley T.; Melis, Rob; Laing, Mark D.; Opio, Fina;     Show all 5 Authors
Source:
Euphytica 2009 v.167 no.3 pp. 303-312
ISSN:
0014-2336
Subject:
Phaseolus vulgaris; dry beans; disease resistance; anthracnose; Colletotrichum lindemuthianum; inheritance (genetics); general combining ability; specific combining ability; additive gene effects; heritability; major genes; incomplete dominance
Abstract:
... Anthracnose is a serious disease affecting dry bean production especially in the cool highland areas worldwide. The objective of this research was to study the inheritance of anthracnose resistance in market-class dry beans. A complete diallel set of crosses was generated from nine diverse parents comprising six resistant and three susceptible to anthracnose. The F₁ and F₂ crosses and parents were ...
DOI:
10.1007/s10681-008-9873-4

39. Gene Action Controlling Gray Leaf Spot Resistance in Southern African Maize Germplasm

Author:
Derera, John,   et al.   ; Tongoona, Pangirayi; Pixley, Kevin V.; Vivek, Bindiganavile; Laing, Mark D.; van Rij, Neil C.;     Show all 6 Authors
Source:
Crop science 2008 v.48 no.1 pp. 93-98
ISSN:
1435-0653
Subject:
Zea mays; corn; Cercospora zeae-maydis; plant pathogenic fungi; fungal diseases of plants; disease resistance; genetic resistance; genes; germplasm; plant genetic resources; hybrids; inheritance (genetics); grain yield; heterosis; general combining ability; specific combining ability; gene interaction; genotype-environment interaction; inbred lines; Africa
Abstract:
... Gray leaf spot disease (GLS; caused by Cercospora zeae-maydis Tehon and Daniels) is among the major maize (Zea mays L.) production constraints in southern Africa. Maize is predominantly grown by small-scale farmers without fungicides; hence, there is need to develop GLS resistant hybrids. There is limited information about the mode of inheritance for GLS resistance in regionally adapted germplasm. ...
DOI:
10.2135/cropsci2007.04.0185