Chapters authored
Rapeseed-Mustard Breeding in India: Scenario, Achievements and Research Needs
Brassica spp., commonly known as rapeseed-mustard, plays a significant role in the Indian economy by providing edible oils, vegetables, condiments and animal feed. Globally, India holds second and third position in rapeseed-mustard area under cultivation and production, respectively. However, anthropogenically accelerated climate change thwarts yield potential of rapeseed-mustard by employing abiotic (drought, flood, temperature variation and salinity) and biotic (disease and insects) stresses. Various approaches such as molecular breeding, pre-breeding, −omics and biotechnological interventions have been used to develop varieties for improved yield and oil quality, climate resilient and resistance or tolerance to abiotic and biotic stresses. In this context, this chapter highlighted the different cytoplasmic male sterility (CMS) sources and their potential use for hybrid development. At the end, this chapter also enlisted salient achievement by the government and non-government institutes and briefly described the future perspective for improvement of rapeseed-mustard in India.
Part of the book: Brassica Breeding and Biotechnology
Genetics of Multiple Alleles: Concept and Function
Mendelian genetics revealed only two alternative forms of a gene called alleles. The concept has evolved with the identification of more than two alternative forms of a gene, commonly referred to as multiple alleles. There are several traits that are governed by multiple alleles, such as ABO blood group system in humans, coat color in rabbits, and self-incompatibility in crop plants. The test of allelism is a very common practice to establish the relationship between alleles of the same or different genes. The inter-mating among different mutants helps to confirm whether mutations are allelic or non-allelic. The structural allelism determines whether two mutations are present at the same or different site in DNA and functional allelism determines whether two mutations are present in the same gene or in different genes. The concept of multiple alleles should not be confused with pseudoalleles and with pseudogenes. Pseudoalleles are two genetically linked genes with similar effects located close to each other on the chromosome, on the other hand, pseudogenes are nonfunctional copies of the functional genes. To understand the allelic relationships among and between genes is always a subject of interest. Therefore, in this chapter, the concept, function, and importance of multiple alleles are discussed.
Part of the book: Advances in Genetic Polymorphisms