172

Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

6.3.2 DISEASE RESISTANCE

In strawberry, resistance against crown gall disease is developed by intro­

ducing the β-1,3-glucanase gene, which made plant resistant to fungal

disease (Mercado et al., 2015). The resistance against conidial growth in

guava plants is developed by the Endochitinase gene taken from Tricho­

derma (Mishra et al., 2016).

In tobacco, Tomato yellow leaf curl China virus resistance is induced by

Zinc finger nuclease (Chen et al., 2014) and resistance against Tobacco curly

shoot virus is introduced by Transcription activator-like effector nuclease

(Cheng et al., 2015). In tobacco, plant tolerance against Tomato leaf curl

Yunnan virus is developed via Transcription activator-like effector nuclease

(Ali et al., 2015). In Arabidopsis thaliana and Nicotiana benthamiana the

gene virus dsDNA (A7, B7, and C3 regions) resistant to beet severe curly top

virus (Ji et al., 2015) and gene eIF(iso)4E is responsible for resistance against

Turnip mosaic virus in Arabidopsis thaliana (Pyott et al., 2016). In rice resis­

tance against Blast is developed by gene OsERF922 (Wang et al., 2016a, b).

In wheat resistance against Powdery mildew is developed by TaMLO-A1,

TaMLO-B1, and TaMLOD1 (Wang et al., 2014). In the cucumber plant,

eIF4E is responsible for creating resistance against Zucchini yellow mosaic

virus, Cucumber vein yellowing virus, and Papaya ringspot mosaic virus

type-W (Chandrasekaran et al., 2016). In cotton plants, CLCuD IR and Rep

regions are resistant to cotton leaf curl disease (Iqbal et al., 2016).

6.4 CONVENTIONAL PLANT BREEDING APPROACHES

Plant breeding approaches play an essential role in developing biotic and

abiotic stress tolerance in plants, making them tackle various stress in plants’

lives at different growth and developmental stages. Many methods are appli­

cable to develop resistance in plants against many diseases, low, and high

temperature, and salt in plants. For instance, mungbean resistance against

biotic stresses has been developed by breeding approaches like introduction,

hybridization, and selection (Pratap et al., 2012).

6.4.1 INTRASPECIFIC PLANT BREEDING APPROACHES

Many studies showed that plants’ resistance against various stresses like

biotic and abiotic stresses could be developed by intraspecific hybridization