Question

Which of the following researcher has first described gametophytic system of self-incompatibility?

• A. East and Mangelsdorf (1925)
• B. Hughes and Babcock (1950)
• C. Lewis (1954)
• D. Gerstel (1950)

Hint:

Historical breakthroughs in genetics are important. East and Mangelsdorf's 1925 work on Nicotiana was foundational for understanding gametophytic self-incompatibility. They proposed that pollen carrying an S-allele identical to one in the pistil would fail to fertilize.

Answer 1

The Correct Option is A

Self-incompatibility (SI) is a genetic mechanism in plants that prevents self-fertilization and promotes outcrossing. There are different types of SI systems. The gametophytic system of self-incompatibility (GSI) is characterized by the SI phenotype of the pollen being determined by its own haploid S-allele. The pioneering work that first described and genetically characterized the gametophytic system of self-incompatibility was conducted by:
(1) East and Mangelsdorf (1925): Edward M. East and his student A. J. Mangelsdorf published seminal papers in 1925 based on their studies with Nicotiana (tobacco) species. They provided the first clear genetic explanation for gametophytic self-incompatibility, proposing the oppositional S-allele model.
(2) Hughes and Babcock (1950) worked on sporophytic self-incompatibility in Crepis foetida.
(3) D. Lewis (1954) made significant contributions to understanding the physiology and genetics of S-alleles, particularly in Oenothera organensis and other species, building upon earlier work.
(4) Gerstel (1950) also worked on self-incompatibility, including studies in Parthenium argentatum (guayule), contributing to understanding polyploidy and SI. However, the first description and genetic model for GSI are credited to East and Mangelsdorf. East and Mangelsdorf (1925)