Increasing the efficiency of water conversion into biomass (TE)
is in focus for improvement of crop productivity under water-
limited environments. The last ID conference highlighted
that stomatal regulation under high vapor pressure can increase
TE, which represented a new opportunity for crop improvement.
While increasing TE leads to enhanced crop production
under drought stress, managing water to assure its availability
for the grain filling period is necessary. Particularly, we will
focus on traits that alter the crop water-use profile during the
season (e.g. canopy size and development), increase TE (e.g.
canopy conductivity and structure), or achieve both. For these
water-use related traits, the range of genetic variability has been
explored and this allowed designing crops suitable for either
agro-systems intensification or resilience. Yet, the interactions
of physiological processes responsible for plant water use with
environments are not fully understood and this talk will provide
an update on these aspects. We will also show how the crop and
socio-economic models are used to quantify the benefits and
evaluate the trade-offs associated with different crop water-use
strategies in semi-arid tropics agro-ecologies. Results indicate
that variation in water-use related traits is frequently associated
with grain versusstover production trade-offs. Therefore, the
economic value of a particular technology intervention depends
on the nature and type of commodity demand within the specific
agro-system. We will discuss the possibilities of enhancing
the crop value in the systems with high demand for staple food
grains ormore complex dual purpose (food and fodder) crop production
systems
