Relative importance of general combining ability and specific combining ability among tropical maize (Zea mays L.) inbreds under contrasting nitrogen environments

dc.creatorWorku, M.
dc.creatorBänziger, M.
dc.creatorFriesen, D.K.
dc.creatorSchulte auf'm Erley
dc.creatorHorst, W.J.
dc.creatorVivek, B.
dc.date2013-06-30T05:24:35Z
dc.date2013-06-30T05:24:35Z
dc.date2008
dc.date.accessioned2023-07-17T19:57:09Z
dc.date.available2023-07-17T19:57:09Z
dc.identifierhttp://hdl.handle.net/10883/3086
dc.identifier.urihttps://repositorioslatinoamericanos.uchile.cl/handle/2250/7509034
dc.descriptionLow-N stress is among the major abiotic stresses causing yield reductions in maize grown in the mid-altitude tropical environments of Africa. This study estimates the relative importance of general combining ability (GCA) and specific combining ability (SCA) in CIMMYT's tropical mid-altitude inbred lines under contrasting N environments. Six hundred and thirty five lines (S2-S7) were evaluated in different crossing designs (Diallels, North Carolina Design II and Line x Tester crosses). Results of experiments conducted under low and high N at the same site in adjacent fields with the same soil type within the same year and season from 1999-2003 were compared. The contribution of GCA to total genetic variation was higher than SCA for anthesis date, ear height and plant height under both high and low N levels. However, contribution of GCA was higher for grain yield only under high-N conditions. The average relative contribution of SCA, indicative of non-additive gene effects, to total genetic variation for grain yield under low-N accounted for 51% (average across all trials) but only for 36% under high-N. Pair-wise t-test for diallels and Design IIs showed significant difference (P<0.05) between the proportion of SCA sum of squares for grain yield under high and low N conditions. This implies that breeding strategies that increase grain yield under optimal (high N) conditions will not address the needs of a resource poor farmer producing maize under low N conditions, especially in sub-Saharan Africa. Targeted strategies that increase yield under low N conditions are thus required.
dc.description279-288
dc.formatPDF
dc.languageEnglish
dc.publisherConsiglio per la Ricerca e la sperimentazione in Agricoltura, Unità di Ricerca per la Maiscoltura
dc.rightsCIMMYT manages Intellectual Assets as International Public Goods. The user is free to download, print, store and share this work. In case you want to translate or create any other derivative work and share or distribute such translation/derivative work, please contact CIMMYT-Knowledge-Center@cgiar.org indicating the work you want to use and the kind of use you intend; CIMMYT will contact you with the suitable license for that purpose.
dc.rightsOpen Access
dc.source03-abr
dc.source53
dc.sourceMaydica
dc.subjectAGRICULTURAL SCIENCES AND BIOTECHNOLOGY
dc.subjectDiallel Cross
dc.subjectGCA
dc.subjectGeneral Combining Ability
dc.subjectNitrogen Environments
dc.subjectNstress
dc.subjectSCA
dc.subjectSpecific Combining Ability
dc.subjectDIALLEL ANALYSIS
dc.subjectCROSS-BREEDING
dc.subjectCOMBINING ABILITY
dc.subjectINBRED LINES
dc.subjectMAIZE
dc.subjectNITROGEN
dc.subjectNUTRIENT DEFICIENCIES
dc.subjectABIOTIC STRESS
dc.subjectZEA MAYS
dc.titleRelative importance of general combining ability and specific combining ability among tropical maize (Zea mays L.) inbreds under contrasting nitrogen environments
dc.typeArticle
dc.coverageAFRICA


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