An unstable gene controlling developmental variegation in okra (Abelmoschus esculentus (L.) Moench)

Abstract

Genetic studies on radiation-induced chlorina and variegated mutants of okra (Abelmoschus esculentus (L.) Moench) revealed the existence of an unstable gene. The normal green color of the leaves is controlled by duplicate genes C1 and C2, either of which produces the green colour. The chlorina plants are C 1 C 1 C 2 C 2. The allele c 1 (v) is dominant to both C 1 and C 2 but is unstable. The homozygote c 1 (v) c 1 (v) c 2 c 2 is a normal green while the heterozygote c i (v) c 1 c 2 c 2 has a variegated phenotype as a result of the mutation of c 1 (v) to c 1 during development. In green plants with a c 1 (v) c{sh1/v}c 2 c 2 genotype, the autonomous mutation of one of the c 1 (v) alleles to c 1 may take place at the pre-meiotic stage. In the variegated genotype (c 1 (v) c 1 c 2 c 2), the mutation of c 1 to c 1 (v) may take place in early ontogeny, thus producing green plants. The allele C 1, when associated with c 1 (v) in a heterozygous condition, mutates to c 1 at the pre-meiotic stage even in the presence of the allele C 2.

Screening of germplasm of Abelmoschus against biotic stresses

“…Rajmony et al (1995) extracted some BYVMV resistant accessions from A. ficulneus and A. angulosus, respectively, which indicated prevalence of accessional variation within the species. Many BYVMV resistant varieties have been developed using wild species A. manihot since 1970 (Thakur 1976) including Parbhani Kranti (Jambhale and Nerkar 1985). Later breakdown of resistance was observed due to pan India use of sole species as source of resistance.…”

Morphological, Molecular, and Biochemical Characterization of a Unique Lentil (Lens culinaris Medik.) Genotype Showing Seed-Coat Color Anomalies Due to Altered Anthocyanin Pathway

“…Such an anomalous seed-coat color in the cases of mottled beans and spotted peas was also observed and termed as a pseudo-mutation by Imai [ 40 ] (1935). Even for the chlorina and variegated mutants of okra ( Abelmoschus esculentus ), an unstable gene was reported [ 41 ]. Interestingly, in previous studies, researchers did not study the mottling pattern, especially in later generations using seed-coat color-based planting and a plant-by-plant study.…”