Biology Reference
In-Depth Information
Chapter 1
Translational Genomics in Crop Breeding for
Biotic Stress Resistance: An Introduction
RajeevK.Varshneyand RobertoTuberosa
Abstract
Biotic stresses pose a major threat to crop productivity. Crops are challenged by a plethora of biotic
stresses, but only a limited number of key pests and diseases cause the vast majority of economic
losses in a particular crop. Plant protection measures such as application of pesticides and deployment
of resistant gene(s)/quantitative trait loci (QTLs) into cultivars have so far been quite successful
in curtailing the losses; however, these measures have also led to the constant evolution of new
biotypes/pathotypes/strains/races of pest and disease organisms. Hence, there is a continuous need
to identify genomic regions that can impart resistance against these variants. The availability of
large-scale genomic resources in many crop species has enhanced our understanding on the path to
developing host-plant resistance. As a result, numerous race-specific gene(s) and QTLs have now
been identified and cloned with the help of molecular markers. It is quite exciting that these genomic
regions are being introgressed into breeding programs of many crops. The objective of this topic is to
critically review the current availability and utilization of genomic tools for major biotic stresses in
important cereals, legumes, vegetables, and tuber and oilseed crop. The topic also summarizes the
success stories achieved through application of genomics-assisted breeding (GAB), as well as the
scope for deployment of modern breeding methods such as marker-assisted backcrossing (MABC)
and genomic selection in the era of next-generation sequencing (NGS) technologies, which have the
potential to advance the genetic gains for enhancing resilience against biotic stress. This chapter
summarizes highlights of different chapters included in the topic that is expected to be a resource
for young researchers, GAB practitioners, and policy makers for employing better strategies toward
achieving food security.
lines based on their agronomic performance, but
the entire process is expensive and takes several
years. During the past two decades, remarkable
progress in the area of genomics and molec-
ular genetics has greatly improved our basic
Introduction
Several biotic and abiotic stresses challenge crop
productivity. Breeders try to develop superior
lines by making crosses and selecting the best
