Search

Maize kernel row number ( KRN) is an important agronomic trait. In this study, 13 quantitative trait loci ( QTL) for maize KRN were identified in different environments using F2:3 and F2:4 populations developed from two inbred lines. These QTL are distributed on chromosomes 2,3,5,8 and 10, and the genic effects are additive or partially dominant. Using the BC3 F2:3 populations developed from the same parental lines, QTL of KRN located on chromosomes 5 and 10 were also identified in two environments. Three BC5 F2:3 populations were used to confirm the major QTL for KRN between ssr1430 and umc1077 on chromosome 10(q KRN10). This result will facilitate the fine mapping and map-based cloning of this major QTL in the future. [ABSTRACT FROM AUTHOR]

Deep-seeding tolerant seeds can emerge from deep soil where the moisture is suitable for seed germination. Breeding deep-seeding tolerant cultivars is becoming increasingly important in arid and semi-arid regions. To dissect the quantitative trait loci (QTL) controlling deep-seeding tolerance traits, we selected a tolerant maize inbred line 3681-4 and crossed it with the elite inbred line-X178 to generate an F population and the derivative F families. A molecular linkage map composed of 179 molecular markers was constructed, and 25 QTL were detected including 10 QTL for sowing at 10 cm depth and 15 QTL for sowing at 20 cm depth. The QTL analysis results confirmed that deep-seeding tolerance was mainly caused by mesocotyl elongation and also revealed considerable overlap among QTL for different traits. To confirm a major QTL on chromosome 10 for mesocotyl length measured at 20 cm depth, we selected and self-pollinated a BCF plant that was heterozygous at the markers around the target QTL and homozygous at other QTL to generate a BCF population. We found that this QTL explained more phenotypic variance in the BCF population than that in the F population, which laid the foundation for fine mapping and NIL (near-isogenic line) construction. [ABSTRACT FROM AUTHOR]