See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/289198510 Heterotic relationship between INERA, CIMMYT and IITA maize inbred lines under drought and well-watered conditions Article  in  Maydica · January 2014 CITATIONS READS 0 75 4 authors: Abdalla Dao Jacob Sanou West Africa Centre for Crop Improvement Institut de l'environnement et de recherches agricoles, Burkina Faso, Farako-Bâ 5 PUBLICATIONS   24 CITATIONS    20 PUBLICATIONS   174 CITATIONS    SEE PROFILE SEE PROFILE Vernon Gracen Eric Y Danquah Cornell University University of Ghana 92 PUBLICATIONS   1,311 CITATIONS    134 PUBLICATIONS   483 CITATIONS    SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: NEXTGEN Cassava View project Generating and releasing best agricultural technics for fonio millet in savanah zone of Senegal (West Africa) View project All content following this page was uploaded by Vernon Gracen on 08 January 2016. The user has requested enhancement of the downloaded file. Original Paper Open Access Heterotic relationship between INERA, CIMMYT and IITA maize inbred lines under drought and well-watered conditions Abdalla Dao1*, Jacob Sanou1, Vernon Gracen2, Eric Y Danquah3 1Institute of Environment and Agricultural Research (INERA), BP 910, Bobo-Dioulasso, Burkina Faso. 2Department of Plant Breeding and Genetics, 520 Bradfield Hall, Cornell University, Ithaca, NY 14850, USA 3West Africa Centre for Crop Improvement (WACCI), University of Ghana, BMP 30, Legon, Accra, Ghana *Corresponding author: E-mail: adao@wacci.edu.gh Abstract The Institute of Environment and Agricultural Research of Burkina Faso has extracted a large number of inbred lines from Open Pollinated Varieties, which are environmentally adapted and adopted by farmers. However, there is a gap in knowledge on heterotic grouping of these lines and their heterotic relationship with exotic lines. Twenty- four CIMMYT and INERA white lines were crossed to two CIMMYT testers and; twenty six IITA and INERA yellow inbred lines were crossed to two IITA testers. Two trials composed of 48 white testcrosses and 52 yellow test- crosses plus three checks were evaluated in well-watered and drought stress conditions in the dry season over two years. Significant general combining ability (GCA) effects due to lines and, testers for many traits including grain yield were observed. However, specific combining ability (SCA) effects for most traits except for plant and ear heights were not significant. Of the 24 CIMMYT and INERA white lines, 15 lines could be classified into het- erotic groups based on the SCA effects and testcross mean grain yield in well-watered environment and, 10 lines were classified under drought stress condition. Eighty five percent of the IITA and INERA yellow lines were clas- sified into heterotic groups in both drought and non-drought conditions. Thirteen yellow lines and five white lines maintained their heterotic groups in both well-watered and water-stressed conditions. Keywords: maize, heterotic patterns, drought Introduction erated from different adapted and adopted open Maize is an important source of calories for a pollinated varieties (OPVs). Inbred lines have been significant portion of the population in sub-Saharan classified mainly based on their performance per se African. Maize provides 50% of the calories in diets and source population. Heterotic groups which have in southern Africa, 30% in eastern Africa and 15% important implications in a comprehensive hybrid in West and Central Africa; of the 23 countries in the breeding program have not been developed. Heter- world with the highest per capita consumption of otic groups enable the exploitation of heterosis in an maize as food, 16 are in sub-Saharan Africa (Bän- efficient and consistent manner through identifica- ziger and Diallo, 2001). Maize production in the Eco- tion of complementary lines. Creation of new heter- nomic Community of West African States (ECOWAS) otic groups for hybrid program development is de- has progressively increased in the last 5 years with sirable (Russell, 1991; Cheres et al, 2000). There is an important contribution from Nigeria of about 50%. little current knowledge of heterotic grouping of lines ECOWAS, representing 17% of the area of the con- developed at INERA maize breeding program. In de- tinent, is one of the most populous economic com- veloping countries, judicious application of available munities in Africa with a regional population of about crop improvement methods and use of both local and 300 million in 2008, of which 57% live in rural areas. exotic germplasm to improve yields and yield stability Burkina Faso is among the top 5 countries in maize are required to meet the increasing demand of im- production in this region. National statistics show proved maize hybrids (Dhliwayo et al, 2009). CIMMYT that maize production in Burkina Faso is increasingly and IITA are the source of maize breeding materials important and the local consumption guarantees a for a significant portion of Africa. CIMMYT and IITA domestic and export market. The successful adop- inbred lines and OPVs are bred to contain consider- tion of the commercial hybrid «Bondofa» in the coun- able diversity and are then taken by National Agricul- try emphasized the need for development of maize ture Research Programs and selected for further ad- cultivars with high yield potential. Cognizant of this aptation in their own particular environment(s). Maize fact, maize breeding program at the Institute of En- germplasm at INERA includes different materials vironment and Agricultural Research, Burkina Faso from CIMMYT and IITA but little is known about the developed and assembled germplasm from various heterotic relationships between CIMMYT and INERA sources. A large numbers of inbred lines were gen- and between IITA and INERA inbred lines. To make Maydica 59-2014 received 07/23/2014 Dao et al 202 effective use of local and exotic germplams, informa- were used as testers for white inbred lines. TZEI 17 tion about their heterotic relationships and combining and TZEI 10, representing heterotic group A and B, ability is desirable. Heterotic groups are not absolute respectively, were used as testers for yellow inbred (Hallauer and Miranda, 1988). Studies show that the lines. heterotic patterns of inbred lines and populations Generation and evaluation of testcross hybrids can change depending on the test environment un- The testcross hybrids were generated during der which evaluation is made (Gutiérrez-gaitan et al, rainy season in 2011 and 2012 at INERA experimen- 1986; Kim and Ajala, 1996; Vasal et al, 1993; Menkir tal station in Farako-Bâ. Thirteen CIMMYT and 11 et al, 2003). Understanding the change in heterotic INERA white inbreds were crossed to VL0511298 response of inbred lines under stress and non-stress and VL054881 to generate 48 white testcross hy- conditions would be useful for the development of an brids. Twelve IITA and 14 INERA yellow inbred lines efficient hybrid breeding strategy. Drought stress is were crossed to TZEI17 and TZEI10 to generate 52 among the major abiotic stresses causing yield re- testcross hybrids. The 48 white hybrids and 52 yel- duction in maize grown in the tropics (Edmeades et low hybrids were randomized separately and laid out al, 1995). However, there are few studies on effect of in different trials but planted at the same time, in the this stress on heterotic patterns of lowland and mid- same location and received the same treatments. The altitude maize inbred lines. white hybrids trial was composed of 48 testcrosses, The objectives of this study were to: i) character- hybrid between the two inbreds used as testers and ise the heterotic patterns of 24 CIMMYT and INERA two local commercial hybrids. The yellow hybrids white and 26 IITA and INERA yellow inbred lines trial was of 52 testcrosses, hybrid between the two for grain yield; ii) classify these lines into heterotic inbreds used as testers and the same local commer- groups; iii) evaluate the effect of sources population cial hybrids. The trials were conducted during the dry of the inbreds and drought stress on heterotic group- season in 2011 and 2012 at field experimental sta- ing of the inbred lines. tion of INERA in Valley du kou located at 11°22’N Latitude, 4°22’W Longitude; and at 300 m above sea Materials and Methods level, characterized by ferruginous and acid soils with Genetic materials silty texture. Thirteen elite CIMMYT mid-altitude white inbred The trials were established and managed accord- lines, twelve elite IITA lowland yellow inbred lines, ing to procedures developed by CIMMYT (Bänziger and 25 advanced INERA white and yellow inbred lines et al, 2000). Adequate irrigation was applied in both were used for this study (Table 1). CIMMYT inbred water regimes from planting and throughout the veg- lines were developed from diverse sources, four lines etative phase, using furrow irrigation system. Drought (VL057903, VL058025, VL057967, and VL058014) stress was achieved in water stressed regime by were developed from an extra-early population de- withholding water two weeks before the expected veloped through reciprocal recurrent selection from flowering time for 21 days. The white and yellow field a wide pool of Southern and Eastern Africa adapted trials were laid out in 17 x 3 and 11 x 5 randomized inbred lines of N3, Kitale, A and Tuxpeño popula- incomplete block design, respectively, with three rep- tion backgrounds. Inbred lines VL05615, VL081464, lications. The experimental unit was one single row of VL081466 were developed from an extra-early popu- 5 m spaced at 80 cm. Two seeds were planted per lation developed through reciprocal recurrent selec- hill spaced 25 cm between and thinned to one plant tion from a wide pool of Southern and Eastern Af- to give a final planting density of 50,000 plants ha-1. rica adapted inbred lines from SC, Ecuador, B, and ETO population backgrounds. Four lines including Data collection and statistical analysis VL054794, T02058, VL0511247, and VL05616 were In each plot, days to anthesis and days to silk- derived from biparental crosses. VL05616 trac- ing were recorded as the number of days from plant- es 50% of its pedigree to a temperate inbred line ing to when 50% of the plants had shed pollen and (FR812). The remaining two inbred lines (VL058589 emerged silks, respectively. Anthesis-silking interval and VL0512593) were developed each from different (ASI) was computed as the interval in days between sources. IITA inbred lines were developed from two dates of silking and anthesis. Plant and ear heights different sources: the broad-based Striga hermon- were measured in cm as the distance from the base thica resistant early yellow population, TZE COMP5- of the plant to the height of the first tassel branch Y and the broad-based Striga hermonthica resistant and the node bearing the upper ear, respectively. and drought tolerant early yellow population, TZE-Y Ear aspect was scored on a 1 to 5 scale, where 1 = Pop DT STR. The eleven white and thirteen yellow «clean, uniform, large and well-filled ears» and 5 = lines from INERA used in the present study were «rotten, variable, small and partially filled ears». The all extracted from the early yellow drought tolerant total number of plants and ears were counted in each Open-pollinated variety, FBC6, which has a mixed plot at the time of harvest. The number of ears per genetic background. VL0511298 and VL054881, plant was then calculated as the proportion of the representing heterotic group A and B, respectively, total number of ears at harvest divided by the total 59 ~ 201-210 Maydica electronic publication - 2014 local and exotic inbreds 203 Table 1 - Inbred lines evaluated in testcrosses with two inbreds testers in well-watered an water-stressed conditions. Inbred lines Origin Pedigree Grain color Maturity T02058 CIMMYT [CML389/CML176]-B-29-2-2-B*6-B white intermediate VL0511247 CIMMYT [INTA-2-1-3/INTA-60-1-2]-X-11-6-3-BBB white intermediate VL0512593 CIMMYT Syn01E2-64-2-B-2-BB white early VL054794 CIMMYT [[[K64R/G16SR]-39-1/[K64R/G16SR]-20-2]- 5-1-2-B*4/CML390]-B-38-1-B-2-#-1-B-2 white intermediate VL05615 CIMMYT ZEWBc1F2-216-2-2-B-2-B*4-4-2-8-B white intermediate VL057903 CIMMYT ZEWAc1F2-151-6-1-B-1-BBB-2-2-BB white early VL057967 CIMMYT ZEWAc1F2-219-4-3-B-1-B*4-1-3-BB white intermediate VL058025 CIMMYT ZEWAc1F2-164-3-2-B-1-BBB-2-2-BB white early VL058589 CIMMYT INTA-F2-192-2-1-1-1-B*7-2-B-3 white early VL081464 CIMMYT ZEWBc2F2-101-2-BB white intermediate VL081466 CIMMYT ZEWBc2F2-110-1-BBB white early VL05616 CIMMYT [SC/CML204//FR812]-X-30-2-3-2-1-B*6 white intermediate VL058014 CIMMYT ZEWAc1F2-254-2-1-B-1-BB-1-3 white early TZEI124 IITA TZE-Y Pop DT STR Co S6 Inbred 3-1-3 yellow early TZEI146 IITA TZE-Y Pop DT STR Co S7 Inbred 49-3-3 yellow early TZEI148 IITA TZE-Y Pop DT STR Co S6 Inbred 62-1-3 yellow early TZEI149 IITA TZE-Y Pop DT STR Co S6 Inbred 66-2-2 yellow early TZEI151 IITA yellow intermediate TZEI158 IITA TZE-Y Pop DT STR Co S6 Inbred 102-2-2 yellow intermediate TZEI16 IITA TZE Comp5-YS C6 S6 Inbred 31 yellow intermediate TZEI161 IITA TZE-Y Pop DT STR Co S6 Inbred 103-2-3 yellow intermediate TZEI177 IITA TZE Comp5-Y C6 S6 Inbred 62-1-2 yellow intermediate TZEI23 IITA TZE-Y Pop DT STR Co S6 Inbred 62-2-3 yellow early TZEI8 IITA TZE-Y Pop DT STR Co S6 Inbred 62-3-3 yellow early TZI18 IITA Sete Lag. 7728 x TZSR yellow intermediate ELN41112 INERA FBC6 x FBMS1 white intermediate ELN41114 INERA FBC6 x FBMS1 white intermediate ELN41115 INERA FBC6 x FBMS1 white intermediate ELN41271 INERA FBC6 x FBMS1 white intermediate ELN41272 INERA FBC6 x FBMS1 white intermediate ELN42441 INERA FBC6 x FBMS1 white intermediate ELN42442 INERA FBC6 x FBMS1 white intermediate ELN42444 INERA FBC6 x FBMS1 white intermediate ELN42445 INERA FBC6 x FBMS1 white intermediate ELN48392 INERA FBC6 x FBMS1 white intermediate FBML10 INERA Derived from Ku1414 yellow intermediate ELN39382 INERA FBC6 x FBMS1 yellow intermediate ELN39427 INERA FBC6 x FBMS1 yellow intermediate ELN402213 INERA FBC6 x FBMS1 yellow intermediate ELN40791 INERA FBC6 x FBMS1 yellow intermediate ELN40823 INERA FBC6 x FBMS1 yellow intermediate ELN40941 INERA FBC6 x FBMS1 yellow intermediate ELN431251 INERA FBC6 x FBMS1 yellow intermediate ELN43453 INERA FBC6 x FBMS1 yellow intermediate ELN43574 INERA FBC6 x FBMS1 yellow intermediate ELN45111 INERA FBC6 x FBMS1 yellow intermediate ELN462121 INERA FBC6 x FBMS1 yellow intermediate ELN464171 INERA FBC6 x FBMS1 yellow intermediate ELN47132 INERA FBC6 x FBMS1 yellow intermediate ELN41111 INERA FBC6 x FBMS1 white intermediate Testers VL0511298 CIMMYT MAS[MSR/312]-117-2-2-1-B*4-2-14-BB white intermediate VL054881 CIMMYT [Ent2:92SEW1-earlySel-22/[DMRESR-W] earlySel-#1-3-2-B/CML390]-B-26-1B-1-#-1-BB-3-1 white intermediate TZEI 17 IITA TZE Comp5-Y C6 S6 Inbred 35 yellow early TZEI 10 IITA TZE-Y Pop DT STR Co S6 Inbred 152 yellow early The maturity of CIMMYT and IITA lines indicated in the table was determined based on a screening in a local environment. 59 ~ 201-210 Maydica electronic publication - 2014 Dao et al 204 number of plants at harvest. Additional data obtained grain yield using the line x tester model. from drought stress plots were the leaf senescence Classification of inbred lines into heterotic groups recoded two times at weekly interval commencing The specific combining ability (SCA) effects and two weeks after stress application on a scale of 1 to mean grain yields of testcrosses of the lines with the 10, where 1 = «almost all leaves were green» and 10 = two testers were used to classify the inbred lines into «virtually all leaves were dead». Leaf rolling recorded heterotic groups for each of the two growing condi- on a scale of 1 to 5, where 1 = «all leaves are un- tions. Lines that showed positive SCA effects with rolled» and 5 = «all leaves are rolled». Leaf rolling was tester A with testcross mean yields equal to or greater recorded three time at weekly intervals, commencing than 10% of the mean yield of hybrid between the a week after stress application; Leaf erectness was two testers but had negative SCA effects with tes- recorded based on visual score of 1 (erect leaves) ter B were placed into anti-A or opposite heterotic to 5 (lax leaves) two times at a weekly interval com- group of tester A. The designation of «anti-A» (op- mencing a week after stress application. Tassel size posite group of tester A) was used instead of «same was recorded two times at weekly interval commenc- group of tester B» because lines belonging to the ing 21 days after stress application based on scale same heterotic group may not have absolutely identi- of 1 (small tassel size) to 5 (large tassel size); Plant cal heterotic patterns (Pswarayi and Vivek, 2008), ex- recovery was recorded at 7 and 14 days after stop- plained by small differences in the alleles they may be ping drought stress on a scale of 1 to 5, where 1 = «all carrying (Rawlings and Thompson, 1962). When lines plants recovered from drought stress» and 5 = «all exhibited positive SCA with tester B with testcross plants were dead». mean yield equal to or greater than 10% of the mean Grain yield was calculated according to the pro- yield of the cross between the two testers but had cedure described by (Menkir et al, 2003). In well- negative SCA with tester A were assigned into anti- watered evaluation, all ears harvested from each plot B or opposite heterotic group of tester B. Lines that were weighed and representative samples of ears showed positive SCA effects with both testers A and were shelled to determine per cent moisture. Grain B with testcross mean yields equal to or greater than yield adjusted to 15% moisture was, thus, computed 10% of the mean yield of hybrid between the two tes- from ear weight and grain moisture assuming a shell- ters were located into anti-A and anti-B groups (or ing percentage of 80%, based on the following for- opposite heterotic groups of A and B) whereas lines mula: grain yield (kg ha-1) = ear weight (kg) x 0.8 x that exhibited negative SCA effects with both testers (100 - moisture) / 85) x (10 / area m2 ) x 1,000. A and B or lines that had testcross mean yields less In water-stressed evaluation, all ears harvested than 10% of the mean of the cross between the two from each plot were shelled to determine per cent testers were not assigned into either heterotic group. moisture. Grain yield adjusted to 15% moisture was computed from the shelled grain based on the follow- Results ing formula : grain yield (kg ha-1) = grain weight (kg) x Means of local and exotic inbred lines evaluated (100 - moisture) / 85) x (10 /area m2) x 1,000. in testcrosses with two inbreds testers in drought and Individual analysis of variance of each tested trait well-watered conditions are presented in Table 2. The in each year and water regime were conducted with differences between testcross means of CIMMYT the PROC MIXED procedure from SAS (SAS, 2002) and INERA inbreds in testcrosses were significant with genotypes being considered as fixed effects, and for grain yield in well-watered condition and not sig- replications and blocks within replication as random nificant under drought stress while the difference was effects. Because the alpha lattice did not provide sig- not significant between IITA and INERA inbreds in nificant efficiency over randomized complete block testcrosses for grain yield in well-watered condition design (RCBD), data were then analysis according but significant under drought stress. When means to RCBD. Combined analysis of variance was con- were averaged over all testcrosses within a water ducted by means of PROC GLM in SAS (SAS, 2002) regime, drought stress reduced plant height, ear using RANDOM statement with Test option. Means height, the number of ears per plant, and grain yield, generated from the analysis of variance for each test while it increased ear aspect, anthesis-silking interval environment were used for the computation of line x and extent flowering time. Grain yield reduction was tester analysis as described by Singh and Chaudhary 47% in yellow testcrosses which was higher com- (1985). For combined analysis in well-watered (WW) pared to 36% in white testcrosses. The increase of and water-stressed (WS) conditions, the significance ASI under drought stress was higher (37%) in yellow of line GCA , tester GCA and line x tester SCA mean testcrosses than white testcrosses (40%). The com- squares were determined using the corresponding in- mercial check, Sanem, was the best check in both teraction with years as error terms. The significance water regimes and in white and yellow testcrosses of GCA lines × year, GCA tester x year and SCA × trails. Twelve white hybrids and five yellow hybrids year interactions was determined using the pooled yielded about 10% more than mean grain yield of error. Effects of GCA and SCA were calculated for Sanem in well-watered condition and, means grain 59 ~ 201-210 Maydica electronic publication - 2014 local and exotic inbreds 205 Table 2 - Means (±SE) of traits averaged over two years for white and yellow testcrosses of inbred lines with two testers, evalu- ated under drought stress and well-watered conditions. Variable well-watered condition water-stressed condition white hybrids yellow hybrids white hybrids yellow hybrids CIMMYT INERA IITA INERA CIMMYT INERA IITA INERA AD 74±0.7 78±0.7 75±0.6 77±0.7 76±1 80±0.9 77±1.3 80±1.1 SD 78±0.7 81±0.8 78±0.6 80±0.7 82±1 85±0.7 82±1.3 85±1 ASI 3.5±0.5 3.3±0.6 2.9±0.5 3±0.5 5.9±0.7 5.3±0.6 4.5±0.8 4.8±0.7 PHT 171±5.2 180±5.5 169±5.3 176±5.4 135±5.4 135±5.4 131±7.9 135±6.5 EHT 63±4.1 72±4.2 76±4 82±4.5 57±3.5 62±4 65±4.7 67±4.9 EASP 2.6±0.3 2.9±0.3 2.4±0.2 2.5±0.2 3±0.2 3.1±0.2 2.8±0.2 2.9±0.2 EPP 0.9±0.1 0.9±0.1 0.9±0.1 0.9±0.04 0.8±0.1 0.8±0.1 0.8±0.1 0.9±0.1 GY 2,475±0.3 2,205±0.3 2,487±0.2 2,628±0.3 1,524±0.2 1,499±0.2 1,238±0.2 1,481±0.3 LR 2±0.2 2±0.2 2.5±0.3 2.5±0.3 SEN 4±0.4 4±0.4 4.9±0.5 4.8±0.5 LE 2.7±0.2 2.5±0.2 2.6±0.2 2.5±0.2 TS 2.7±0.2 2.8±0.2 2.8±0.2 2.9±0.2 PR 3±0.4 2.8±0.3 3.1±0.4 2.8±0.4 AD = anthesis-days (50%); SD = silking-days (50%); ASI = anthesis-silking interval; PHT = plant height; EHT = ear height; EASP = ear aspect; EPP = ear per plant; GY = grain yield (kg ha-1); LR = leaves rolling; SEN = leaves senescence; LE = leaves erectness; TS = tassel size; PR = plant recovery. yield of two white hybrids and three yellow hybrids, On average, white testcrosses with VL0511298 con- in drought stress condition, were higher than that of sistently out-yielded those with VL054881 by 13% Sanem by 10%. under well-watered and 26% under water-stressed Combined analysis of variance for grain yield and condition; but VL054881 x ELN42444 was one of the other agronomic traits of the white and yellow test- best hybrids under both water regimes. Hybrids with crosses are presented in Table 3 for well-watered VL0511298 did better under drought stress. Yellow condition and Table 4 for water-stressed condition. testcrosses of TZEI10 out-yielded those of TZEI17 by Significant differences were detected among CIM- 4% under well-watered condition but under drought MYT and INERA lines for anthesis-days (AD), anthe- stress yellow testcrosses of TZEI17 out-yielded by sis-silking interval (ASI) and ear height (EHT) under 11% those of TZEI10. both well-watered and water-stressed conditions, Mean grain yields of six white testcrosses with while the difference was significant among IITA and VL0511298 tester involving three lines (VL058025, INERA lines only for AD under both water regimes. VL057967, and VL058014) with Tuxpeño background, The variation among white lines (GCA) was signifi- two lines (VL054794 and T02058) developed from bi- cant for grain yield (GY) under drought stress and parental crosses, one line (VL05615) with ETO back- for ears aspect (EASP) and plant height (PHT) under ground and three INERA lines (ELN42441, ELN48392, well-watered condition; and the variation among yel- and ELN42445) were higher than that of the hybrid low lines was significant for GY, EPP and PHT under between testers (VL0511298 x VL054881) by at least well-watered condition. The two testers within each one standard error in the well-watered environment. testcross group differed significantly only for AD Tester VL0511298 produced, in the drought stress under drought stress. The line x tester interactions environment, five testcrosses with at least one stan- (SCA) were generally not significant for many traits dard error higher than that of VL0511298 x VL054881 in both white and yellow testcrosses and under both with four lines (VL054794, T02058, VL05616, and water regimes. However SCA effects were significant VL0511247) derived from biparental crosses and for plant and ear height in well-watered condition one line (VL057967) with Tuxpeño background. for yellow testcrosses. Among the drought adaptive Yield increases of these testcrosses over VL051198 traits including leaf rolling (LR), senescence (SEN) x VL054881 varied from 14% to 28% in the well- and erectness (LE), tassel size (TS) and plant recov- watered environments and from 20% to 38% in the ery (PR) measured only under drought stress condi- drought stress environments. tion, GCA mean square were significant only for TS Five hybrids with tester VL054881 crossed with and PR in white testcrosses and for LE in white and three CIMMYT lines, VL05616, VL0511247 (biparen- yellow testcrosses. Mean square of tester GCA was tal crosses), and VL058025 (Tuxpeno background) significant only for PR in yellow testcrosses. There and two INERA lines (ELN42442 and ELN42444) were no significant SCA effects for the four adaptive out-yielded the hybrid between testers (VL0511298 drought traits in either testcrosses group. x VL054881) by at least one standard error in the Testcross means and estimates of GCA and SCA well-watered condition with a yield increase over effects of the white and yellow lines for grain yield VL0511298 x VL054881 from 11% to 27%. But tes- are presented in Table 5 and Table 6 respectively. ter VL054881 produced, in drought stress condition, 59 ~ 201-210 Maydica electronic publication - 2014 Dao et al 206 Table 3 - Percent of corrected total sum of squares from the combined analysis of variance for the testcross hybrids of 26 IITA and INERA yellow and, 24 CIMMYT and INERA white inbred lines evaluated in well-watered condition at Valley du kou, in Burkina Faso, for two years. Source DF GY EPP EASP AD ASI PHT EHT White testcross hybrids Year 1 0.05 0.35*** 1.18 448.91*** 98.61*** 179,224.07*** 12,201.49*** GCALine 23 1.61 0.03 1.49** 84.61*** 11.82** 1,012.81*** 704.69*** GCATester 1 7.90 0.03 1.06 227.26* 9.72 418.68 1,434.6 SCALine x Tester 23 1.01 0.02 0.47 9.55 2.28 302.93 97.02 Year xGCALine 23 0.81 0.03 0.53 8.70*** 3.17 162.08* 92.81 Year x GCATester 1 0.53 0.04 0.73 0.46 5.88 25.76 259.24 Year x SCALine xTester 23 0.86* 0.01 0.68 5.48* 2.76 114.16 103.89 Yellow testcross hybrids Year 1 10.58*** 0.23*** 36.72*** 12.45 55.46*** 20,7001.54*** 25,219.08*** GCALine 25 1.24* 0.030* 0.91 31.97*** 3.47 501.66* 276.75 GCATester 1 0.28 0.03 1.66 55.13*** 7.66 476.80 9.29 SCALine x Tester 25 0.83 0.03 0.62 5.78 2.04 362.42** 236.77** Year x GCALine 25 0.52 0.01 0.85** 5.79* 2.73* 221.08 198.19 Year x GCATester 1 0.18 0.14** 0.21 0.00 0.48 1,423.81* 423.28 Year x SCALine xTester 25 0.66 0.01 0.37 5.12 1.80 120.61 71.99 AD = anthesis-days (50%); ASI = anthesis-silking interval; PHT = plant height; EHT = ear height; EASP = ear aspect; EPP = ear per plant; GY = grain yield (t ha-1). only one hybrid with INERA line (ELN42444) that TZEI151) under drought stress had significantly posi- was at least one standard error higher than that of tive GCA effects. VL0511298 x VL054881 with 15 % of yield increased. Heterotic grouping of CIMMYT and INERA white Mean grain yields of 11 yellow testcrosses with lines each tester, TZEI17 and TZEI10, involving seven Of the 24 lines, 15 were assigned into one het- INERA lines and 4four IITA lines were higher than that erotic group by either of the two testers under well- of the hybrid between testers (TZEI17 x TZEI10) by watered condition (Table 5). Of these, 10 were clas- at least one standard error in the well-watered en- sified into anti-VL0511298 heterotic group and five vironments. In addition four testcrosses with TZEI17 into anti-VL054881 heterotic group. About 42% (10 involving three IITA and one INERA lines, and seven out of 24) of lines were classified into heterotic group testcrosses with TZEI10 including four IITA and three under drought stress with nine lines assigned into INERA lines out-yielded the hybrid between testers anti-VL0511298 heterotic group and one line into an- (TZEI17 x TZEI10) by at least one standard error. Un- ti-VL054881 heterotic group. Four lines (ELN41272, der drought stress, each of the two yellow testers T02058, VL054794, and VL057967) in anti-VL0511298 (TZEI17 and TZEI10) produced nine testcrosses, six heterotic group and one line (ELN42444) in the anti- with INERA and three IITA lines, with at least one VL054881 group maintained their groups under both standard error higher than that of TZEI17 x TZEI10, water regimes. Anti-VL0511298 heterotic group in- and mean grain yields of seven hybrids with TZEI17 cludes more than 50% of CIMMYT as well as INERA involving four INERA and three IITA lines and three lines compared to anti-VL054881 group under both hybrids including two IITA and one INERA line were well-watered and water-stressed conditions. higher than that of TZEI17 x TZEI10 by at least one Heterotic grouping of IITA and INERA yellow lines standard error. Yield increases of these yellow test- Eighty five percent (22 out of 26) of lines were as- crosses over TZEI17 x TZEI10 varied from 11% to signed into one heterotic group by either of the two 41% in the well-watered environment and from 19% testers in each of the two water regimes (Table 6). to 56% in the drought stress environment Eleven lines were classified into each group under The number of white lines with positive GCA ef- well-watered condition. Twelve lines were assigned fects for grain yield was 14 under well-watered condi- into anti-TZEI17 heterotic group and ten into anti- tion and 11 under drought stress. Of these, only two TZEI10 group under drought stress condition. lines (ELN42442 and VL058025) under well-watered Seven lines (ELN39382, ELN40791, ELN43574, condition and three lines (T02058, VL054794, and ELN45111, TZEI146, TZEI151, and TZEI8) in the an- VL057967) under drought stress had significantly ti-TZEI17 heterotic group and six lines (ELN39427, positive GCA effects. Eleven and thirteen yellow TZEI124, TZEI149, TZEI16, TZEI177, and TZEI23) lines had positive estimates of GCA effects for grain in the TZEI10 group maintained their groups under yield under well-watered and water-stressed condi- both water regimes. The distribution of the number of tions, respectively. Of these, four lines (ELN431251, IITA and INERA lines in each of the two groups was ELN43574, ELN45111, and TZI18) under well-watered fairly equal in well-watered environment. Anti-TZEI17 condition and three lines (ELN39427, ELN43574, and 59 ~ 201-210 Maydica electronic publication - 2014 local and exotic inbreds 207 Table 4 - Percent of corrected total sum of squares from the combined analysis of variance for the testcross hybrids of 26 IITA and INERA yellow and, 24 CIMMYT and INERA white inbred lines evaluated in drought stress condition at Valley du kou, in Burkina Faso, for two years. Source DF GY EPP EASP AD ASI PHT EHT LR SEN LE TS PR White testcross hybrids Year 37.05* 1.62*** 1.68* 0.88 104.56*** 14,501.76*** 5,261.49*** 29.82*** 162*** 27.40*** 2.26** 341.26*** GCALine 23 1.12* 0.06 0.20 16.67*** 16.672* 333.64 330.04*** 0.21 2.44 1.58** 1.07*** 2.40*** GCATester 1 14.83 0.29 2.92 16.64 16.64 869.47 1,833.47 1.13 0.17 3.52 2.20 5.15 SCALine x Tester 23 0.40 0.05 0.26 7.79 7.79 322.42 86.81 0.38 1.53 0.48 0.31 1.18 Year xGCALine 23 0.48 0.05 0.33 11.87** 7.039*** 304.54 79.37 0.34 1.70 0.43 0.22 0.61 Year x GCATester 1 1.97* 0.17* 0.35 26.75* 7.88 33.17 14.67 1.04 1.25 0.98 1.28 0.73 Year x SCALine xTester 23 0.38 0.03 0.19 9.43 4.19 306.24 89.15 0.30 1.14 0.41 0.24 0.72 Yellow testcross hybrids Year 6.43** 0.84*** 1.91* 1,711.68*** 7.81 7,548.12*** 1,093.67* 56.27*** 305.81*** 8.48*** 3.81*** 84.27*** GCALine 25 0.93 0.04 0.42 35.35** 10.31 540.88 269.98 0.45 2.52 1.45** 0.43 1.72 GCATester 1 1.95 0.01 0.01 148.87 9.18 909.96 1,424.87 0.01 0.00 12.69 6.04 5.56* SCALine x Tester 25 0.57 0.06 0.33 8.09 6.15 308.90 140.53 0.46 1.78 0.26 0.23 1.56 Year x GCALine 25 0.76* 0.05 0.77** 12.17 8.29** 520.15 203.10 0.52 2.99 0.46 0.37 1.38 Year x GCATester 1 0.37 0.11 0.04 5.15 0.07 308.16 805.95* 2.72 2.10 1.86 1.98 0.01 Year x SCALine xTester 25 0.50 0.04 0.35 6.71 3.23 317.68 121.15 0.52 1.80 0.29 0.24 0.93 AD = anthesis-days (50%); ASI = anthesis-silking interval; PHT = plant height; EHT = ear height; EASP = ear aspect; EPP = ear per plant; GY = grain yield (t ha-1); LR = leaves rolling; SEN = leaves senescence; LE = leaves erectness; TS = tassel size; PR = plant recovery. heterotic group, under drought stress, predominantly 24 CIMMYT and INERA white lines into complemen- contained INERA lines (67%) and anti-TZEI10 group tary heterotic groups based on SCA effects and grain included 60% of IITA lines. yield of the testcrosses in well-watered condition and 42% under drought stress. Of these, means grain Discussion yield of 12 hybrids, under well-watered environment, The average yield of all the hybrids was 2.4 t ha -1 and two hybrids, under drought stress, were higher under well-watered condition and 1.4 t ha -1 under than that of the best commercial check (Sanem) by drought condition. This yield performance was with- 10%. On the other hand, the two IITA testers were in the range of the yield potential of extra-early and able to separate 85% of the IITA and INERA yel- early maturing hybrids reported, under similar condi- low lines into two contrasting heterotic groups in tion. Akaogu et al (2012) obtained a mean of 2.8 and both water regimes based on SCA effects and grain 1.7 t ha -1 for hybrids created with extra-early inbred yield of the testcrosses. But only five hybrids, under lines in Striga free and Striga infested environments, well-watered condition, and three hybrids, in water- respectively. CIMMYT mid-altitude early maturing hy- stressed condition, yielded about 10% more than brids were evaluated under drought, low nitrogen and the best commercial check. The outstanding hybrids optimum conditions and the mean yield of the trials over the best commercial check could be released was 2.1, 3.2, and 8.3 t ha -1 respectively (Pswarayi for commercial use and or include into three way and and Vivek, 2008). Grain yield of some hybrids evalu- double cross hybrids breeding program. The testers ated in this study across trials were superior com- were not previously evaluated for local adaptation, pared to the best local commercial check (Sanem). however they classified both local and exotic lines. However the actual yield of Sanem in these trials was The proportion of local and exotic lines in the two op- very low compared to its yield potential estimated at posite heterotic groups tended to be similar indicat- 10.5 t ha -1. This difference could be explained by the ing that the grouping of the lines was not based on dry and cold weather which affected the yield per- the origin (breeding program) of the lines but on the formance of all the hybrids evaluated and also the heterotic reaction between the testers and lines. This low plant density. The use of elite inbred lines with suggests that the testers used in the present study known heterotic patterns as testers to classify inbred could be used in INERA maize breeding program to lines into opposite heterotic groups was suggested evaluate local as well as CIMMYT and IITA lines for (Melchinger and Gumber, 1998; Melchinger, 1999) combining ability estimates and heterotic patterns. and used routinely, especially in private sector breed- Although the number of local and exotic inbred lines ing programs. The four testers, two each from CIM- used in this study was rather low, the results show MYT (VL051128 and VL054881) and IITA (TZEI17 and that the CIMMYT lines derived from source popula- TZEI10) used in this study, correspond to two oppo- tion with Tuxpeño background and from biparental site heterotic groups which have been identified and crosses tend to be in the opposite heterotic group of used in CIMMYT and IITA maize breeding programs. the tester, VL0511298 (group A). Two line (VL057967 The two white and two yellow testers exhibited con- and VL058025) with Tuxpeño background and two trasting GCA effects in both well-watered and water- lines (T02058 and VL054794) derived from bipa- stressed environments. rental crosses had consistently positive SCA effect The two CIMMYT testers classified 63% of the in crosses with tester, VL0511298 (group A) in both well-watered and water-stressed environments and 59 ~ 201-210 Maydica electronic publication - 2014 Dao et al 208 Table 5 - Mean grain yields, general combining ability (GCA) and specific combining ability (SCA) effects for 13 CIMMYT and 11 INERA white lines in testcrosses with two testers under well-watered and drought stress conditions at Valley du kou, for two years. Well-watered condition Water-stressed condition Grain Yield (t ha-1) Grain Yield (t ha-1) Lines VL0511298 (A) VL054881 (B) GCA effects SCA effects Heterotic VL0511298 (A) VL054881 (B) GCA effects SCA effects Heterotic (t ha-1) with VL0511298 group (t ha-1) with VL0511298 group ELN41111 2.03 2.13 -0.27 -0.22 NA 1.48 1.4 -0.07 -0.19 NA ELN41112 2.20 1.73 -0.39 0.06 NA 1.35 1.19 -0.24 -0.15 NA ELN41114 1.54 1.30 -0.92 -0.06 NA 0.74 1.17 -0.56 -0.44 NA ELN41115 2.03 1.43 -0.62 0.13 NA 1.92 0.89 -0.11 0.28 antiA ELN41271 2.42 2.2 -0.04 -0.06 NA 2.28 1.44 0.35 0.19 antiA ELN41272 2.59 2.15 0.02 0.06 antiA 2.07 1.46 0.25 0.07 antiA ELN42441 2.93 2.36 0.29 0.12 antiA 1.72 1.3 0 -0.02 NA ELN42442 2.51 3.22 0.52 -0.52 antiB 2.08 1.46 0.26 0.08 antiA ELN42444 2.16 2.91 0.18 -0.54 antiB 1.63 1.83 0.22 -0.33 antiB ELN42445 2.74 1.98 0.01 0.21 antiA 1.83 1.45 0.13 -0.04 NA ELN48392 2.82 0.99 -0.45 0.75 antiA 1.57 0.72 -0.36 0.20 NA T02058 2.73 2.05 0.04 0.17 antiA 2.27 1.6 0.42 0.10 antiA VL0511247 2.24 2.91 0.25 -0.53 antiB 1.94 1.47 0.14 0.05 antiA VL0512593 2.11 1.80 -0.4 -0.01 NA 1.41 1.11 -0.25 -0.08 NA VL054794 3.00 1.93 0.11 0.37 antiA 2.48 1.58 0.52 0.22 antiA VL05615 2.92 2.24 0.23 0.18 antiA 1.5 1.09 -0.22 -0.03 NA VL05616 2.47 2.67 0.22 -0.27 antiB 2.23 1.25 0.23 0.26 antiA VL057903 2.55 2.62 0.24 -0.2 antiB 1.37 1.11 -0.27 -0.10 NA VL057967 3.17 2.48 0.47 0.18 antiA 2.49 1.59 0.53 0.22 antiA VL058014 3.06 2.41 0.38 0.16 antiA 1.48 1.12 -0.21 -0.05 NA VL058025 3.24 2.64 0.59 0.14 antiA 1.59 0.96 -0.24 0.09 NA VL058589 2.51 2.00 -0.09 0.09 NA 1.43 0.97 -0.31 0.00 NA VL081464 2.46 2.07 -0.09 0.02 NA 1.75 1.58 0.15 -0.14 NA VL081466 1.97 2.05 -0.34 -0.21 NA 1.29 1.13 -0.31 -0.15 NA VLAxVLB 2.34 2.34 1.55 1.55 Bondofa 1.39 1.39 1.16 1.16 Sanem 2.45 2.45 2.17 2.17 Mean 2.47 2.16 0 0 1.73 1.32 0 0 SE 0.29 0.29 0.26 0.26 0.22 0.22 0.19 0.17 SE = standard error; VLA x VLB = VL0511298 x VL054881; antiA = anti-VL0511298 (or opposite group of VL0511298); antiB = anti-VL054881 (or opposite group of VL054881); NA = not assigned. the hybrids out-yielded hybrid between testers by FBC6 (source population) was developed from the 10%. This finding is not in agreement with earlier ob- mixture of eight different varieties with different ge- servations indicating that CIMMYT group A exhibits netic composition and geographical origin. Out of heterosis similar to N3, Tuxpeño, Kitale and Reid; and the lines that were separated into heterotic groups, group B exhibits heterosis similar to SC, ETO Blanco, 48% of exotic lines (CIMMYT, IITA) and 65% of local Ecuador and Lancaster (Mickelson et al 2001; Pswa- lines (INERA) did not show consistent heterotic clas- rayi and Vivek, 2008). Tester, TZEI17 derived from sification between well-watered and water-stressed TZE COMP5-Y population, showed consistent posi- environments. Knowing that the exotic lines were se- tive SCA effects with three IITA lines (TZEI 151, TZEI lected for drought resistance contrary to local lines, 146, and TZEI 8) derived from the same population this result could suggest that the heterotic patterns of as tester TZEI10, TZE-Y Pop DT STR, in both water the lines are less affected by the effect of the environ- regimes. It produced hybrids that yielded between ment when they carry favourable alleles for a stress or 255 and 1350 kg ha-1 better than TZEI17 x TZEI10. In have broad adaptation. parallel, three lines (TZEI124, TZEI149, and TZEI23) More than 50% of the inbred lines had consis- derived from the same population as tester TZEI10 tent positive or negative GCA effects for grain yield and 2 lines (TZEI16 and TZEI177) derived from the in the two evaluation environments. However, only 2 source population as tester TZEI17, exhibited a con- white lines (VL058025 and ELN42442) and four yellow sistent positive SCA effects in crosses with TZEI10 in lines (ELN431251, ELN43574, ELN45111, and TZI18) both well-watered and water stressed environments had significant positive GCA effects for grain yield in and the hybrids out-yielded hybrid between testers the well-watared environment. Inbred line, ELN43574 by 10%. These results suggest that the two source had significant positive GCA effects for grain yield in populations could be regarded as two broad oppo- well-watered as well as water-stressed conditions. site heterotic groups. The white and yellow INERA The adapted inbred lines having significant positive lines extracted from the same source, FBC6, showed GCA effects for grain yield, may be used as a testers diverse heterotic response with both CIMMYT tes- in establishing heterotic patterns for the grain yield of ters as well as both IITA testers. These inbred lines local inbred lines. were classified into different heterotic groups, con- The results of these experiments indicate that firming the mixed genetic background of the source exotic testers with contrasting heterotic response population. This was expected since the composite could be used to separate adapted and exotic inbred 59 ~ 201-210 Maydica electronic publication - 2014 Dao et al 209 Table 6 - Mean grain yields, general combining ability (GCA) and specific combining ability (SCA) effects for 14 IITA and 12 INERA yellow lines in testcrosses with two testers under well-watered and drought stress conditions at Valley du kou, for two years. Well-watered condition Water-stressed condition Grain Yield (t ha-1) Grain Yield (t ha-1) Lines TZEI17 (A) TZEI10 (B) GCA effects SCA effects Heterotic TZEI17 (A) TZEI10 (B) GCA effects SCA effects Heterotic (t ha-1) with TZEI17 group (t ha-1) with TZEI17 group ELN39382 2.8 1.80 -0.26 0.53 antiA 1.48 0.87 -0.19 0.23 antiA ELN39427 1.84 2.84 -0.18 -0.51 antiB 1.68 2.12 0.55 -0.32 antiB ELN402213 1.78 2.98 -0.13 -0.62 antiB 1.66 1.34 0.12 0.10 antiA ELN40791 2.73 2.79 0.20 0.00 antiA 1.90 1.59 0.38 0.08 antiA ELN40823 1.93 2.12 -0.55 -0.05 NA 1.20 1.84 0.12 -0.37 antiB ELN40941 3.07 2.68 0.31 0.23 antiA 1.65 1.58 0.25 -0.04 antiB ELN431251 3.36 2.72 0.48 0.36 antiA 1.37 1.28 -0.04 -0.03 antiB ELN43453 2.04 2.16 -0.47 -0.03 NA 0.86 1.09 -0.38 -0.20 NA ELN43574 3.2 2.75 0.41 0.25 antiA 2.37 1.80 0.72 0.21 antiA ELN45111 3.41 2.9 0.60 0.29 antiA 1.84 1.37 0.24 0.16 antiA ELN462121 2.19 2.34 -0.29 -0.04 NA 0.94 0.95 -0.42 -0.08 NA ELN464171 2.74 3.00 0.31 -0.10 antiB 1.79 0.95 0.00 0.34 antiA ELN47132 1.96 2.8 -0.18 -0.38 antiB 1.18 1.03 -0.26 0.0003 antiA FBML10 2.58 3.60 0.36 -0.31 antiB 1.51 1.16 0.03 0.04 antiA TZEI124 2.51 3.36 0.38 -0.39 antiB 1.15 1.59 0.02 -0.31 antiB TZEI146 2.87 2.46 0.10 0.24 antiA 1.83 0.9 0.00 0.39 antiA TZEI148 2.64 2.07 -0.21 0.31 antiA 1.35 1.39 0.00 -0.09 antiB TZEI149 2.22 2.56 -0.17 -0.13 antiB 1.25 1.54 0.03 -0.22 antiB TZEI151 2.79 2.31 -0.06 0.32 antiA 2.41 1.74 0.70 0.26 antiA TZEI158 2.21 2.21 -0.35 0.04 NA 1.73 0.62 -0.19 0.48 antiA TZEI16 1.97 2.37 -0.39 -0.17 antiB 0.60 1.27 -0.43 -0.41 antiB TZEI161 2.79 2.28 -0.03 0.29 antiA 0.93 1.03 -0.39 -0.12 NA TZEI177 1.97 2.45 -0.35 -0.21 antiB 1.25 1.22 -0.14 -0.06 antiB TZEI23 2.22 2.66 -0.12 -0.19 antiB 1.35 1.35 -0.02 -0.08 antiB TZEI8 2.67 2.55 0.05 0.09 antiA 1.31 0.93 -0.25 0.12 antiA TZI18 3.00 3.31 0.59 -0.13 antiB 0.84 0.85 -0.52 -0.08 NA TZEI17xTZEI10 2.12 2.12 1.06 1.06 Bondofa 1.51 1.51 1.08 1.08 Sanem 2.93 2.93 2.08 2.08 Mean 2.48 2.57 0 0 1.44 1.3 0 0 SE 0.25 0.25 0.2 0.23 0.25 0.25 0.25 0.20 SE = standard error; antiA = anti-TZEI17 (or opposite group of TZEI17); antiB = anti-TZEI10 (or opposite group of TZEI10). lines into complementary heterotic groups. The het- under drought stress and well-watered conditions erotic patterns observed in this study suggests that underscore the need to develop beforehand toler- the adapted inbred lines would produce high yielding ant lines which would will be more likely to express hybrids under drought and non-drought conditions consistent heterotic response under unpredictable when crossed with CIMMYT or IITA inbred lines of rainfall conditions. the opposite heterotic group. The exotic lines would contribute favourable alleles for yield potential and Acknowledgements stress tolerance. The two groups of adapted and ex- This research was conducted at Institute of Envi- otic inbred lines with opposite heterotic response can ronment and Agricultural Research (INERA), Farako- be inter-crossed separately to provide two comple- Bâ, Burkina Faso, in collaboration with West Africa mentary populations (Vasal et al, 1992). The use of Centre for Crop Improvement (WACCI) and funded by such complementary populations would facilitate the Alliance for Green Revolution in Africa (AGRA). The development of superior hybrids, as lines extracted authors express their appreciation to Dr C Magoro- from one population would be expected to combine kosho (CIMMYT/Zimbabwe) and Dr B Badu-Apraku well with the lines from the opposite complementary (IITA) for genetic materials offered. population (Menkir et al, 2003). Another option would be to select within each heterotic group lines having specific traits of interest that the tester and other lines References lack. Each of these lines could, then, be crossed in Akaogu C, Badu-Apraku B, Adetimirin OV, Vroh-Bi I, pair wise combinations to produce source popula- Oyekunle M, and Akinwal RO, 2012. Genetic di- tions and new lines selected for combinations of de- versity assessment of extra-early maturing yellow sirable traits. maize inbreds and hybrid performance in Striga- Elite inbred lines identified among INERA, CIM- infested and Striga-free environment. Journal of MYT and IITA lines, with consistently positive GCA Agricultural Science, 151: 519–537 and SCA effects across stress-free and drought con- Bänziger M, Diallo AO, 2001. Stress-tolerant Maize ditions could have broad utility in local maize breed- for Farmers in Sub-Saharan Africa, pp. 1-8. In: ing program. The extreme changes in heterotic re- Maize research highlights 1999-2000. CIMMYT, sponse of some INERA lines (non drought tolerant) Mexico 59 ~ 201-210 Maydica electronic publication - 2014 local and exotic inbreds 210 Cheres MT, Miller JF, Crane JM, Knapp, SJ, 2000. Menkir A, Badu-Apraku B, The C, Adepoju A, 2003. 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