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Plant Breeding Approaches in Developing Stress Tolerance

barley without this gene (Hasanuzzaman et al., 2013). Arabidopsis HSFA1a

and HSFA1b genes are tolerant to heat stress. In tomato HSFA1 gene is able

to tolerate high temperature stress (Hasanuzzaman et al., 2013).

6.2.4 LOW TEMPERATURE

A lot of genes in the plant are responsible for inducing cold stress toler­

ance in plants. Fatty acids desaturation is essential for the performance of

membrane in low-temperature stress. LOS4 and AtNUP160 genes of Arabi­

dopsis that send RNA to cytoplasm from nucleus are very important to tackle

low-temperature stress in plants (Sanghera et al., 2011).

6.3 GENETIC MECHANISM AGAINST BIOTIC STRESSES

Various genes in plants are tolerant to biotic stress, especially by pathogens

(Mamgain et al., 2013). ABA-independent dehydration-responsive DREB2A

is directly involved in developing disease resistance in plants (Agarwal et

al., 2006). OsDREB1B gene in Transgenic tobacco plants is responsible for

tackling plants’ disease (Gutha & Reddy, 2008). OsEREBP1 gene is respon­

sible for the fungus Magnaporthe grisea. However, transcriptome analysis

showed that it belongs to WRKY and NAC groups (Jisha et al., 2015).

The SlAREB1 gene has increased the expression of PR proteins in plant

(Orellana et al., 2010). ATAF1 gene increases tolerance against Blumeria

graminis f. sp. Graminis but decreased tolerance against Botrytis cinerea,

Pseudomonas syringae and Alternaria brassicicola (Puranik et al., 2012).

OsNAC6 gene in rice plant is responsible for developing resistance against

rice blast (Nakashima et al., 2007).

6.3.1 INSECT PEST RESISTANCE

In the okra plant, the target gene Cry1AC causes resistance against fruit borer

and stem borer (Narendran et al., 2013). A sbtCry1AC gene in Planch is

responsible for developing Oraesia excavate resistance (Zhang et al., 2015a,

b, c). In Daisy, resistance against aphids is induced via CmWRKY48 gene

introduction, which plays many functions in favor of plants to control aphids

(Li et al., 2015).