Genetic and molecular responses of legumes in a changing environment - Legumes Under Environmental Stress: Yield, Improvement and Adaptations - page 199

Chapter 12

Genetic and molecular responses of legumes
in a changing environment

Mustafeez Mujtaba Babar 1 , Najam-us-Sahar Sadaf Zaidi 1 , Mohamed Mahgoub Azooz 2 and
Alvina Gul Kazi 1
1 Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology (NUST), Islamabad, Pakistan
2 Department of Botany, Faculty of Science, South Valley University, Qena, Egypt

12.1 Introduction threats. Various stress factors that burden the growth of

these plants and the observed subcellular changes are
also reviewed.

A number of environmental and biological factors tend
to adversely affect the health of a plant. These stress
factors result in significant damage, especially to the
quality and yield of cultivated plants. Leguminous
plants are no exception in this regard. Legumes form an
important part of the botanical sphere and are valuable
sources of nutrients, drugs and biofuels. Moreover, they
contribute significantly to the environmental and agri-
cultural fields by establishing symbiotic relationships
with nitrogen-fixing bacteria. Keeping in mind the
importance of legumes, any threat to the health of these
plants can present a severe challenge to agriculturalists
and plant pathologists. The environmental stress factors
are mainly changes in the soil's nutrient content, water
levels, temperature changes and other variations in the
microenvironment (Liancourt et al., 2013; Lipiec et al.,
2013; Putten et al., 2013). Plants, like all organisms, tend
to respond to these stress factors by bringing about both
physiological and morphological changes. A complex
series of events, at the genetic and subcellular levels, is
triggered to protect the plant from these harms and to
induce tolerance against these stress conditions (Duque
et al., 2013; Reyer et al., 2013). A number of genes, bio-
molecules, solutes, solvents, ions and regulatory
elements are involved in developing resistance against
an environmental stress factor (Echevarría-Zomeño
et al., 2013; Jacques et al., 2013; Kwon et al., 2013;
Lindemose et al., 2013). The current review focuses on
the genetic, molecular and cellular changes adopted by
legumes to defend themselves against environmental

12.2 Legumes: a botanical treasure

Legumes belong to the family Leguminosae (Fabaceae),
commonly referred to as the bean or pea family. They
are among the most widely cultivated plant species.
Different varieties of these plants are found in diverse
temperature and geographical zones. The family com-
prises around 23,000 species, providing an important
source of nutrients, bioenergy, medicines and biomate-
rials (Tetsukazu et al., 2013). These properties make
them one of the most widely cultivated plant familes.
Legumes are grown over an area of approximately 250
million hectares around the globe (Abate et al., 2012).
Nutritionally, legumes are rich sources of proteins,
carbohydrates, amino acids, vitamins and minerals.
Many members of the family form part of staple diets in
middle to lower income countries. The high protein
content makes them an ideal nutritional choice.
Legumes also contain a variety of phytochemicals
including flavonoids, coumarins, anthraquinones, gly-
cosides and lectins (Kumar et al., 2012). These
plant-derived secondary metabolites are used in many
traditional medicinal systems to treat diseases of the car-
diovascular, respiratory, genitourinary and nervous
systems (Bouchenak & Lamri-Senhadji, 2013; Butt &
Sultan, 2013). Apart from their direct use in human
nutrition and medicinal systems, legumes play an