Mapping of Quantitative Trait Loci for Resistance to Fall Armyworm and Southwestern Corn Borer Leaf‐Feeding Damage in Maize

Abstract

Fall armyworm [FAW, Spodoptera frugiperda (J. E. Smith)] and southwestern corn borer (SWCB, Diatraea grandiosella Dyar) are damaging insect pests of maize (Zea mays L.) that result in significant yield and economic losses. A previous study identified quantitative trait loci (QTL) that contribute to reduced leaf‐feeding damage by these insects in the maize mapping population created by crossing Mp704 (resistant) × Mo17 (susceptible). The current study reports a more complete map by adding 151 simple sequence repeat (SSR) and single‐nucleotide polymorphism markers to the original map of 73 SSRs for QTL analysis. Composite interval mapping (CIM) identified 24 QTL explaining up to 26.5% of the total phenotypic variation (chromosome bin 9.03), and multiple interval mapping (MIM) identified 36 QTL (including five new QTL found compared with the previous study) and 10 interactions for FAW leaf‐feeding damage. Twenty‐nine QTL explaining up to 29% of the total phenotypic variation (chromosome bin 7.02) were identified using CIM for SWCB leaf‐feeding damage, and 21 QTL (including five new QTL) and 11 interactions were identified using MIM for this trait. The addition of significantly more markers to the previously reported map allowed for the identification of new QTL and a better assessment of QTL positions and effects, which can improve breeding applications and the detection of candidate genes controlling FAW and SWCB resistance.

Evaluation of XL370A-Derived Maize Germplasm for Resistance to Leaf Feeding by Fall Armyworm1

“…Native sources of resistance to the pest could be used by maize breeders to enhance current control efforts. A series of 'Mp__' inbred lines were developed in Mississippi that use maize germplasm from Antigua (CIMMYT, El Batan, Mexico) as the resistant donor (Williams and Davis 1997, Mohan et al 2006, Womack et al 2018. Two inbred lines, 'FAW7061' and 'FAW7111' (Ni et al 2000), derived from population GT-FAWCC(C5) (Wiseman et al 1996), were developed for resistance to leaf feeding by fall armyworm, with 'FAW7061' as resistant as check 'Mp708' (Williams et al 1990).…”

Evaluation of Maize Germplasm from Saint Croix for Resistance to Leaf Feeding by Fall Armyworm1

“…2 (CIMMYT, El Batan, Mexico) as the resistant donor (Williams and Davis 1997). Biochemical and genetic mechanisms of resistance have been well characterized (Mohan et al 2006, Womack et al 2018. In addition, two inbred lines, 'FAW7061' and 'FAW7111' (Ni et al 2000), derived from population GT-FAWCC(C5) (Wiseman et al 1996), were developed for resistance to leaf feeding by fall armyworm with 'FAW7061' as resistant as check 'Mp708' (Williams et al 1990).…”

Fall‐armyworm invasion, control practices and resistance breeding in Sub‐Saharan Africa

“…Fall armyworm is also capable of partially or totally devouring maize grain, thereby reducing grain quality and ultimately grain yield (Harrison et al., 2019). In the Americas, FAW infestations have been reported to cause yield losses ranging from 25 to 100%, depending on the severity of infestations (Arias et al., 2011; De Oliveira et al., 2018; Womack et al., 2018).…”

“…Farmer experiences and research on FAW in maize during the past 100 yr in Mesoamerica have drawn some key lessons that can be used to effectively manage and control FAW in areas where it has recently invaded (Assefa & Ayalew, 2019; Tambo et al., 2019). Traditionally, the Americans have been controlling FAW using host‐plant resistance, insecticides (synthetics and botanicals), cultural practices (including early planting, crop rotations, and intercropping), and IPM approaches (Abrahams et al., 2017; Tambo et al., 2019; Womack et al., 2018). Farmers and researchers in SSA need to adopt and customize some of these strategies to suit the African farming practices according to farm size and various socio‐economic factors (Tambo et al., 2019; Wightman, 2018).…”

“…New cultivars can be developed through introgression of the FAW‐tolerance genes into locally adapted but FAW‐susceptible inbred lines, as Womack et al. (2018) suggested. Zimbabwe's national maize‐breeding program, collaborating with CIMMYT and the International Atomic Energy Agency, carried out mutation induction in locally adapted materials.…”