Induction and comparison of different in vitro morphogenesis pathways using embryo of cumin (Cuminum cyminum L.) as a model material

Abstract

In this study, using cumin embryo as explant and manipulating plant growth regulators (PGRs) in regeneration medium, the main in vitro morphogenesis pathways including direct shoot organogenesis, direct somatic embryogenesis, indirect somatic embryogenesis, and indirect shoot organogenesis were obtained. The effects of PGRs, subculture, and light on the induction and progression of different pathways were studied in detail. Direct shoot organogenesis occurred on the meristematic zone, while direct somatic embryogenesis was observed on hypocotyl part of cumin embryo (more differentiated part). Application of BAP (0.1 mgl À1 ) was the sole triggering factor for induction of callus and indirect regeneration pathways. Exogenous IAA played the central role in the direct somatic embryogenesis pathway; however, the combined effects of IAA and NAA along with the high endogenous cytokinin level resulted in direct shoot organogenesis. Subculturing revealed accelerating effects on direct somatic embryogenesis pathway and callus formation. Conversely, subculturing had negative effect on direct shoot organogenesis pathway. In certain combinations of PGRs, like 0.4 mgl À1 IAA + 0.4 mgl À1 NAA, co-induction and co-regeneration of different pathways were observed. Investigation of genotype dependencies of different pathways showed that direct pathways are more genotype-dependent, stable, and faster than indirect pathways. This research presents the embryo of cumin as a convenient model material for induction and comparison of different morphogenesis pathways.

Effect of Growth Regulators on In Vitro Morphogenic Response of Boscia senegalensis (Pers.) Lam. Poir. Using Mature Zygotic Embryos Explants

“…Rapid regeneration is a procedure with low incidence of undesirable somaclonal variation. A lot of minor genes and environmental factors affect regeneration through callus [ 24 ]. In contrast, direct regenerations are more stable, simple and needs less time to regenerate a large number of plants with low incidence of somaclonal variation and chromosomal abnormalities [ 25 ].…”

“…Presence of many types of responses were observed on explant, especially embryo, and have been reported. Ebrahimie et al [ 24 ] reported both direct shoot organogenesis and somatic embryogenesis on the embryo explants of Cuminum cyminum . Direct shoot organogenesis occurred on the meristematic zone, while direct somatic embryogenesis was observed on the hypocotyl part of the embryo.…”

Microprojectile bombardment mediated genetic transformation of embryo axes and plant regeneration in cumin (Cuminum cyminum L.)

“…Sharifi (1995) used hypocotyl and cotyledon as an explant in cumin tissue culture and Tawfik andNoga (2001, 2002) used hypocotyls, internodal stem and leaflet for regeneration. Ebrahimie et al (2003Ebrahimie et al ( , 2006Ebrahimie et al ( , 2007 used embryos as explant and obtained large number of shoots without any intermediated callus formation and sub culturing. Our objective is to establish a convenient method of genetic transformation in cumin, therefore we have selected cumin embryos as explant for genetic transformation using biological constraint independent biolistic gene gun method.…”

Secondary somatic embryogenesis versus caulogenesis from somatic embryos of Aesculus carnea Hayne.: developmental stage impact

“…The authors reported both somatic and zygotic embryos of 8-10 mm long to be optimal for SSE induction, whereas those reaching 12-14 mm were incapable for SSE formation. Somatic embryogenesis and caulogenesis can occur simultaneously within the same explant (Budimir 2003;Ebrahimie et al 2007), or can be completely separated (Ebrahimie et al 2007). Morphogenic responses can also be modified by managing culture conditions, such as sucrose and PGR content in the culture media (Charrière and Hahne 1998).…”