In maize, grain yield is the most important trait having a complex
inheritance pattern. Yield contributing traits are more stable and have
higher heritability than yield. Therefore, the present study was conducted
to identify quantitative trait loci (QTLs) associated with grain yield and
its components by using simple sequence repeat (SSR) markers. A population
of 169 BC1F5 lines was derived from the crossing between maize inbred line
DI-103 and teosinte-parviglumis was utilized for genotyping and phenotyping.
In diseased stressed condition (E1), ear length (EL), ear diameter (ED),
kernel rows per ear (KR/E), kernels per row (K/R), test weight (TW), and
grain yield per plant (GY/P) had 7, 6, 7, 4, 6 and 5 QTLs whereas, in
controlled condition (E2) 5, 2, 5, 4, 5 and 3 QTLs were detected for
enlisted characters, respectively. Consistent QTLs across the environments
were detected for 5 of the 6 investigated traits and number of QTLs were EL
(2), ED (1), KR/E (3), TW (1), and GY/P (1) whereas, for K/R none of the
QTLs were common between E1 and E2. By mapping analysis, we have identified
genomic regions associated with two traits in a manner that was consistent
with phenotypic correlations among traits, supporting either pleiotropy or
tight linkage among QTLs. Three co-localized QTLs were identified between
grain yield and contributing traits. Notably umc1720-linked QTL at bin 4.10
was simultaneously responsible for GY and EL, ED, KR/E, K/R; umc1215-linked
QTL at bin 6.03 was simultaneously responsible for GY and ED, KR/E, K/R, TW;
umc1279-linked QTL was responsible for GY and ED, TW. The findings suggest
that the chromosomal region containing co-localized QTLs governing multiple
yields associated traits are potential targets for selection. In addition
for 6 studied traits, 44 superior lines were identified, and along with both
the parents i.e. maize (DI-103) and teosinte they were clustered in 11
groups. Therefore, lines clustered independently can be utilized in a
hybridization programme for the accumulation of yield contributing traits
for yield maximization.