138 S. Signorelli et al.
This suggests that the tolerance in reproductive stages should be accompanied
by physiological responses to deal with water restriction and high temperatures.
Another key physiological mechanism in the survival of legumes is their ability to
mobilize carbohydrates to storage tissues that can be located on the crown, root or
rhizome (Castillo et al. 2012 ). However, it is critical that the photosynthetic activ-
ity remains active during the stress period to achieve significant accumulation of
sugars allowing regrowth of the shoot after stress.
6.7 Breeding Approaches for Improving Tolerance
to Combined Abiotic Stresses
Selection for one abiotic stress tolerance in the field is very challenging due to in-
teractions among the different stresses. Thus, the only strategy to identify the traits
to be applied in field for breeding tolerant genotypes is by performing experiments
Fig. 6.4 Seasonal dry matter production of L. corniculatus under two-seed set management. With
seed set ( solid line) and without seed set ( dashed line). (Ayala and Carámbula 2009 )
Fig. 6.3 Seedlings
emergence of L. tenuis
during a typical of temperate
zones from south hemisphere
(Ayala and Carámbula 2009 )