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Plant Breeding Approaches in Developing Stress Tolerance

in plants. In mungbean, many varieties against biotic (mostly powdery

mildew and mungbean yellow mosaic disease) and abiotic stresses have

been developed through intraspecific approaches in plant breeding (Pratap

et al., 2014a, 2015; Singh et al., 2017). Hybridization is a powerful tool in

varietal development against biotic and abiotic stresses. The development

of stress-tolerant verities leads to boost agricultural production in less and

reasonable amounts. For example, a cross between PS 16 X BM4 leads to

develop mungbean variety PKV AKM which is highly resistant to stresses.

Through IPM 99–125 and Pusa Bold 2, the most resistant variety of mung-

bean against diseases, especially mungbean yellow mosaic disease, has been

developed, showing about 82.52% of preharvest spouting value (Lamich­

hane et al., 2017). KM 2328 is developed by the cross between KM 2241

and HUM 16 in 2018, which is resistant to MYMD, WB, and anthracnose

(Coordinated Research Project on MULLaRP, Project Coordinators Report,

2018). IPM 205-7 is highly tolerant to high temperatures and matures earlier

than others (Pratap et al., 2013).

6.4.2 INTERSPECIFIC PLANT BREEDING APPROACHES

Inter-specific plant breeding approaches are of great importance to develop

resistance against biotic and abiotic stresses in plants. The exotic and wild

cultivars of mungbean can create resistance against various stresses and

improve yield quality and quantity (Pratap et al., 2015). Inter-specific

crosses are the complex and complicated process of gene transmission to

create resistant verities in the plant, such as mungbean (Pratap et al., 2018).

Improved F7 RILS and subsequent advanced generation of mungbean is

obtained by intercrossing between V2802 and NM94, which is resistant

against bruchid damage in Taiwan (Schafleitner et al., 2016). Intercrossing

between urdbean and mungbean results in variety resistant to MYMD (Gill

et al., 1983; Lekhi, 2017).

6.5 MOLECULAR PLANT BREEDING APPROACHES

6.5.1 QTL MAPPING

QTL mapping is another molecular approach used when more than one

gene is responsible for a trait in a specific chromosome location. The basic

principle of QTL mapping is the segregation of genes during meiosis. Using