Review Paper : Breeding wheat for yield maximization under conservation agriculture

Abstract

Wheat based food security is being challenged due to
declining profit, deteriorating production environment and
changing climatic conditions. Conservation agriculture (CA)
imbibing some components of the natural ecosystem can
address some of these issues quite effectively. Wheat
breeding so far, has managed to increase grain yield mainly
by improving harvest index (HI) and adaptation through
phenological manipulation. With limited scope for further
increase in HI, an increase in biomass appears inevitable
for wheat yield consolidation. The conflict between
increased biomass and lodging that imposes a limitation
to higher grain yield may have an answer in CA. The
production environment under CA is much more congenial
than conventional and hence offers an opportunity for
identification of higher yielding genotypes. The article
discusses the breeding issues and key traits for selection
for yield maximization under CA. Integrating agronomic
perspectives including cropping system, countering the
tradeoff between stress adaptation and yield enhancement
through management has been proposed. Selection indices
build around increased coleoptile length, weed
competitiveness, mild vernalization, increased duration and
higher biomass could facilitate the development of CA
adapted genotypes. These traits can be further fine-tuned
according to different cropping and management practices.