关键词: 爆裂玉米, 三倍体胚乳, 数量性状位点, QTL定位

Abstract: 【Objective】The objective of this study was to investigate the molecular genetic basis of popping characteristics in popcorn and provide useful message for their genetic improvement and MAS. 【Method】Two hundred and fifty-nine F2:3 families, derived from the cross between Dan232, a dent corn inbred and N04, a popcorn inbred, were evaluated for popping characteristics under two environments. One hundred and eighty three pairs of SSR markers were used to construct the genetic map. Quantative trait loci (QTL) were identified and their effects were evaluated for PR (popping rate), PV (popping volume) and PF (popping fold), using triploid endosperm genetic model and interval mapping method. 【Result】The genetic linkage map spanned 1762.2 cM (centimorgan) and was on an average interval of 9.63 cM. Popping characteristics in popcorn were quantitative in nature, which were controlled by multiple genes with different effects and influenced by environments simultaneously. A total of 56 QTL with significant effects were detected under two environments, the numbers of QTL were 18, 17 and 21 for PR, PV and PF, respectively. Contribution to phenotypic variation of a single QTL varied from 4.4% to 28.0%, and total contributions of all QTL were from 65.8% to 96.6%. The amount of QTL showing additive, partial dominant, dominant and over-dominant effects were 2, 1, 4, 20 and 1, 5, 1, 22, respectively. Over-dominance played the most important role in their genetics. 【Conclusion】This was not consistent with the result of previous researches, in which additive effect was always considered as the most important part. The main reasons might be the detailed division of dominant effect and its overestimation for QTL with small dominant effect by the triploid endosperm genetic model.

Key words: Popcorn (Zea mays L. everta Sturt), Triploid endosperm, Quantitative trait loci (QTL), QTL analysis