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also general agreement that high latitude spring wheat production will benefit from
a warmer climate through an extension of the growing period (Sommer et al. 2013).
In this chapter, we assessed the effect of climate change on wheat cultivated area
and total production under five production alternatives, namely traditional cultivation, raised beds cultivation, application of deficit irrigation to wheat grown on
raised beds, implementing intercropping systems for wheat and use the saved irrigation water from other winter crops to cultivate new lands with wheat. Our aim was
to produce more wheat seeds to increase its national production and to reduce its
production-consumption gap.
8.2 Effect of Heat Stress on Wheat
Heat stress is expressed as the rise in air temperature beyond a threshold level for a
period sufficient to cause injury or irremediable damage in plants in general
(Teixeira et al. 2013). In wheat, heat stress affects various plant processes leading to
morphophysiological alterations in plants, hindering the development processes and
eventually resulting into great yield loss (Grant et al. 2011). The primary effect of
heat stress is the impediment of seed germination and poor stand establishment in
wheat (Hossain et al. 2013) and it negatively affects plant meristems (Kosova et al.
2011). Almeselmani et al. (2009) observed that high temperature (35/25 °C)
imposed after tillering showed a significant reduction in water potential in wheat
and reduces plant growth by promoting leaf senescence and abscission (Kosova
et al. 2011). Heat stress in wheat during anthesis causes reduction in pollen tube
development, and increases of pollen mortality (Oshino et al. 2011). Plants exposed
to temperatures above >24 °C during reproductive stage significantly reduced grain
yield and yield reduction continued with increasing duration of exposure to high
temperature (Prasad and Djanaguiraman 2014). It reduces the number of grains
leading to lower harvest index in wheat (Lukac et al. 2011). Increase in temperature
of 1–2 °C reduces seed mass by accelerating seed growth rate and by shortening
grain-filling periods in wheat (Nahar et al. 2010). Heat stress speeds up the rate of
seed filling by reducing the duration of this stage and therefore the yield potential
(Kaushal et al. 2016). Other damages were observed under heat stress, namely it
decreases metabolic activities (Farooq et al. 2011), and production of oxidative
reactive species (Wang et al. 2011).
8.3 Effect of Climate Change on Wheat
It was reported by Valizadeh et al. (2014) that a rise in temperature under climate
change condition has had negative impacts on the grain filling period causing reduction in the growing season, reduction in harvest index and yield losses in comparison to the current situation. Asseng et al. (2014) tested 30 wheat crop simulation
8 Climate Change and Wheat Self-Sufficiency
also general agreement that high latitude spring wheat production will benefit from
a warmer climate through an extension of the growing period (Sommer et al. 2013).
In this chapter, we assessed the effect of climate change on wheat cultivated area
and total production under five production alternatives, namely traditional cultivation, raised beds cultivation, application of deficit irrigation to wheat grown on
raised beds, implementing intercropping systems for wheat and use the saved irrigation water from other winter crops to cultivate new lands with wheat. Our aim was
to produce more wheat seeds to increase its national production and to reduce its
production-consumption gap.
8.2 Effect of Heat Stress on Wheat
Heat stress is expressed as the rise in air temperature beyond a threshold level for a
period sufficient to cause injury or irremediable damage in plants in general
(Teixeira et al. 2013). In wheat, heat stress affects various plant processes leading to
morphophysiological alterations in plants, hindering the development processes and
eventually resulting into great yield loss (Grant et al. 2011). The primary effect of
heat stress is the impediment of seed germination and poor stand establishment in
wheat (Hossain et al. 2013) and it negatively affects plant meristems (Kosova et al.
2011). Almeselmani et al. (2009) observed that high temperature (35/25 °C)
imposed after tillering showed a significant reduction in water potential in wheat
and reduces plant growth by promoting leaf senescence and abscission (Kosova
et al. 2011). Heat stress in wheat during anthesis causes reduction in pollen tube
development, and increases of pollen mortality (Oshino et al. 2011). Plants exposed
to temperatures above >24 °C during reproductive stage significantly reduced grain
yield and yield reduction continued with increasing duration of exposure to high
temperature (Prasad and Djanaguiraman 2014). It reduces the number of grains
leading to lower harvest index in wheat (Lukac et al. 2011). Increase in temperature
of 1–2 °C reduces seed mass by accelerating seed growth rate and by shortening
grain-filling periods in wheat (Nahar et al. 2010). Heat stress speeds up the rate of
seed filling by reducing the duration of this stage and therefore the yield potential
(Kaushal et al. 2016). Other damages were observed under heat stress, namely it
decreases metabolic activities (Farooq et al. 2011), and production of oxidative
reactive species (Wang et al. 2011).
8.3 Effect of Climate Change on Wheat
It was reported by Valizadeh et al. (2014) that a rise in temperature under climate
change condition has had negative impacts on the grain filling period causing reduction in the growing season, reduction in harvest index and yield losses in comparison to the current situation. Asseng et al. (2014) tested 30 wheat crop simulation
8 Climate Change and Wheat Self-Sufficiency