Fusarium stalk rot disease (FSR), incited by Fusarium
verticilloides, is becoming an important biotic production
constraint in many major maize growing areas causing
substantial yield losses. The present investigation was
conducted to understand the genetics of resistance to FSR
through six generation means and variances, as a first step
in addressing the problem. Five crosses were developed
by crossing four FSR susceptible inbreds (VL1043,
VL108867, VL121096 and VL1218) with two resistant inbreds
(CM202 and CM212). Six generations of the five crosses
(VL1043 × CM212, VL108867 × CM202, VL121096 × CM212,
VL1218 × CM202 and VL1218 × CM212) were evaluated
through artificial disease inoculation during post rainy
season of 2018 and summer, 2019. The scaling tests and
joint scaling tests indicated the inadequacy of additivedominance model and showed the presence of epistatic
gene effects in all the five crosses for FSR resistance. The
study further revealed the importance of additive,
dominance and additive × additive gene effects in the
expression of FSR. The magnitude and direction of the
additive genetic effects [a], dominance genetic effects [d],
magnitudes of additive genetic variance (σ2A) and
dominance genetic variance (σ2D) varied with the genetic
background of the crosses over seasons. Duplicate gene
interaction was evident in the inheritance of FSR resistance.
Both, additive and non-additive components were found
important thus reciprocal recurrent selection would be more
effective in obtaining FSR resistant maize inbred lines.
Keywords: Maize, Fusarium stalk rot, generation means, additive-dominance model, duplicate gene interaction
Year: 2020
Volume: 80
Issue: 4
Article DOI: 10.31742/IJGPB.80.4.5
Print ISSN: 0019-5200
Online ISSN: 0975-6906
B. M. Showkath Babu, H. C. Lohithaswa, A. Mohan Rao and N. Mallikarjuna info_circle