Assessment of 10 years of maize pedigree breeding for European corn borer tolerance and high-yielding combining ability

Selection efficiency of tunnel length and stalk breakage to obtain maize inbred lines resistant to stem borer attack

“…Pedigree selection has been and remains the backbone of hybrid maize breeding (Duvick 2005). It was performed not only for increasing yield but for broadening the genetic base of cultivated maize and improving other agronomical traits such as adaptation, and resistance to drought stress, diseases and pests (Mayfield et al 2012;Ordás et al 1994;Panouille et al 1998;Tarter et al 2003;Carena et al 2009;Reid et al 2009).…”

“…Efforts to develop selection inbred lines resistant to the first or second generation of corn borers by pedigree or backcross selection have been successful (Russell et al 1975;Abel et al 2000a;Abel et al 2000b;Willmot et al 2005;Butron et al 2006). However, transfer of second-generation corn borer resistance from an American inbred line to adapted early European inbred lines has failed probably due to linkage between resistance to stem tunneling by borers and unfavorable characters which have been systematically contra selected (Panouille et al 1998). Consequently, pedigree selection in Central Europe has been made for tolerance rather than for resistance using a discontinuous scale that takes into account stalk breakage (1 = little damage, 2 =broken tassel, 3 =broken tassel and upper leaves, 4.5 = broken upper stalk and 9 = broken stalk under the ear) (Panouille et al 1998).…”

“…However, transfer of second-generation corn borer resistance from an American inbred line to adapted early European inbred lines has failed probably due to linkage between resistance to stem tunneling by borers and unfavorable characters which have been systematically contra selected (Panouille et al 1998). Consequently, pedigree selection in Central Europe has been made for tolerance rather than for resistance using a discontinuous scale that takes into account stalk breakage (1 = little damage, 2 =broken tassel, 3 =broken tassel and upper leaves, 4.5 = broken upper stalk and 9 = broken stalk under the ear) (Panouille et al 1998). Therefore, there is not any conclusive result about the most suitable trait for performing pedigree selection for improving maize performance against corn borer attack: tunnel length or stalk breakage.…”

Recent trends in management strategies for two major maize borers: Ostrinia nubilalis and Sesamia nonagrioides

“…Nonetheless, selection for increased resistance appeared to be associated with lower yield, so new efforts were focused on selection for tolerance, defined as the plants' ability to reduce yield loss when attacked by insects. Recurrent selection for tolerance to O. nubilalis resulted in yield increases of 0.49 Mg ha −1 for uninfested plots and 0.74 Mg ha −1 for infested plots; meanwhile, 63 flint and dent inbred lines, adapted to European conditions, with high-yielding feature and appreciable levels of O. nubilalis tolerance were developed and released (Anglade 1972;Panouillé et al 1998).…”

Why do entomologists and plant pathologists approach trophic relationships so differently? Identifying biological distinctions to foster synthesis

“…First, insect pest management can afford to rely more heavily on biological, cultural and semiochemical controls, and on delaying pesticide applications until populations reach economic thresholds. Second, plant tolerance can provide a specific target for breeding, such as with injury and yield loss to European corn borer infestations (Panouill e et al, 1998). Tolerance has the added benefit of not imposing selective pressures on the herbivore while safeguarding yield, thus de-escalating the genetic arms race between insects and plants (P aez et al, 2017;Peterson et al, 2017).…”